On-Demand System Information

Abstract

To provide a wireless network that may provide system information by either a fixed periodic broadcast or broad-beam transmission or in response to a request by user equipment (UE).SOLUTION: The wireless network may broadcast (or broad-beam transmit) a signal that indicates to one or more UEs within a cell or zone coverage area that system information is to be transmitted on a fixed periodic schedule or in response to a request sent by the UEs.SELECTED DRAWING: Figure 3A

Description

[Technical Field]

[0001] cross reference This patent application claims priority to U.S. Patent Application No. 14 / 803,793 by Kubota et al., entitled "On-Demand System Information," filed July 20, 2015; U.S. Provisional Patent Application No. 62 / 121,326 by Horn et al., entitled "Service Based System Information Acquisition," filed February 26, 2015; and U.S. Provisional Patent Application No. 62 / 114,157 by Kubota et al., entitled "On-Demand System Information," filed February 10, 2015, each of which is assigned to the assignee of the present application.

[0002] The present disclosure relates, for example, to wireless communication systems, and more particularly, to transmission of on-demand system information in wireless communication systems, such as wireless communication systems having user equipment (UE)-centric networks. [Background technology]

[0003] Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcasts, etc. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, and Orthogonal Frequency Division Multiple Access (OFDMA) systems.

[0004] By way of example, a wireless multiple-access communication system may include several base stations, each simultaneously supporting communication for multiple communication devices, also known as user equipment (UE). The base stations may communicate with the UEs over downlink channels (e.g., for transmissions from the base stations to the UEs) and uplink channels (e.g., for transmissions from the UEs to the base stations).

[0005] In a wireless multiple-access communication system, each cell of the network may broadcast synchronization signals and system information for UEs to discover. Upon discovering the synchronization signals and system information broadcast by a particular cell, the UE may perform an initial access procedure to access the network through the cell. The cell through which the UE accesses the network may be the UE's serving cell. As the UE moves within the network, the UE may discover other cells (e.g., neighboring cells) and determine whether UE handover or cell reselection to a neighboring cell is warranted. Summary of the Invention [Means for solving the problem]

[0006] The present disclosure relates generally to wireless communication systems, and more particularly to transmission of on-demand system information in wireless communication systems, such as wireless communication systems having user equipment (UE)-centric networks. Wireless communication systems, such as Long Term Evolution (LTE) communication systems or LTE-Advanced (LTE-A) communication systems, have network-centric networks. In wireless communication systems having network-centric networks, the network constantly broadcasts synchronization signals and system information for UEs to discover. Upon discovering the synchronization signals and system information broadcast by a particular cell, the UE may perform an initial access procedure to access the network through the cell. Once connected to the network, the UE may discover other cells as it moves within the network. The other cells may broadcast different synchronization signals or system information. Thus, wireless communication systems having network-centric networks involve the broadcasting of various signals, which consume power and may or may not be received or used by some or all of the UEs in the cell.

[0007] A wireless communication system with a network-centric network also imposes relatively more network processing on the UE (e.g., the UE identifies a first serving cell when it first accesses the network, and then identifies and monitors handover targets (other serving cells) as part of mobility management). Accordingly, this disclosure describes a wireless communication system in which system information may be transmitted after being requested by one or more UEs. In some cases, the system information may be transmitted to the UE in unicast or narrow beam operation. In some cases, the wireless communication system in which the system information is transmitted may have a UE-centric network.

[0008] In a first set of illustrative examples, a method for wireless communication in a user equipment (UE) is described. In one configuration, the method may include receiving a first signal, the first signal including an indication of whether system information is to be requested by the UE, and obtaining the system information according to the indication.

[0009] In some embodiments of the method, obtaining the system information may include transmitting a request for the system information in accordance with the indication and receiving the system information in response to the request. In some embodiments of the method, obtaining the system information may include receiving the system information via a second signal in accordance with the indication. The second signal may be transmitted via broadcast or broad beam operation. In some embodiments of the method, receiving the first signal may include receiving information indicating where the request for the system information is to be transmitted by the UE. In some embodiments of the method, receiving the first signal may include receiving information indicating a predetermined channel over which the system information is to be transmitted via a second broadcast signal via broadcast or broad beam operation. In some embodiments of the method, the first signal may be a synchronization signal.

[0010] In some embodiments of the method, receiving the first signal may include receiving the first signal as part of broad beam operation in a massive multiple-input / multiple-output (MIMO) network. In these embodiments, obtaining the system information may include receiving the system information as part of broad beam or narrow beam operation.

[0011] In some embodiments of the method, receiving the first signal may include receiving the first signal as part of a broadcast operation in a non-massive MIMO network. In some embodiments, obtaining the system information may include receiving the system information as part of a broadcast or unicast operation.

[0012] In some embodiments, the method may further include identifying one or more services for which system information is to be obtained, and obtaining the system information may include obtaining the system information for the identified one or more services according to the instructions above. In these examples, obtaining the system information may include sending a request for system information for the one or more services and receiving the system information for the one or more services in response to the request. In some examples, obtaining the system information may include sending a separate request for system information for each of the one or more services, each request being for system information for a different service, and individually receiving the system information for the one or more services in response to each request.

[0013] In some embodiments of the method, the indication may be a first indication, and receiving the first signal may include receiving a second indication that system information for one or more services should be broadcast at one or more predetermined times and on one or more predetermined channels.

[0014] In some embodiments of the method, the indication may be a first indication, and receiving the first signal may include receiving a second indication that system information for one or more services is available. In these examples, obtaining the system information may include transmitting one or more requests for system information for the one or more services in accordance with the first and second indications, and receiving the system information for the one or more services in response to the one or more requests. In some of these examples, receiving the first signal may include receiving information identifying a target device to which the one or more requests for system information for the one or more services should be transmitted. In some examples, receiving the first signal may include receiving information identifying one or more time periods corresponding to when the one or more requests for system information for the one or more services should be transmitted, each time period corresponding to a separate service of the one or more services. In some embodiments of the method, obtaining the system information may include receiving system information for the one or more services via one or more second signals, the one or more second signals being transmitted via broadcast or broad beam operation.

[0015] In some embodiments of the method, obtaining the system information may include receiving system information for one or more services, the system information including information identifying one or more services for which the system information is valid. Additionally or alternatively, obtaining the system information may include receiving system information for one of the one or more services, determining whether additional system information for one of the one or more services is needed, and requesting the additional system information for one of the one or more services based at least in part on the determination.

[0016] In some embodiments of the method, the one or more services may include one or more of an energy efficient service, a reliable service, a low latency service, a broadcast service, or a small data service.

[0017] In some embodiments of the method, obtaining the system information may include receiving system information for one or more services, the system information including information identifying a validity period, and re-obtaining the system information for the one or more services upon expiration of the validity period. The validity period may be based on a power saving mode (PSM) period or a length of time to cycle through all value tags of the system information.

[0018] In a second set of illustrative examples, an apparatus for wireless communication in a UE is described. In one configuration, the apparatus may include means for receiving a first signal, the first signal including an indication of whether system information should be requested by the UE, and means for acquiring the system information in accordance with the indication. The means for acquiring the system information may include means for transmitting a request for the system information in accordance with the indication and means for receiving the system information in response to the request. In some embodiments of the method, the apparatus may further include means for identifying one or more services for which system information should be acquired. In these cases, the means for acquiring the system information may include means for acquiring system information for the identified one or more services in accordance with the indication. In some examples, the apparatus may further include means for performing one or more aspects of the method for wireless communication described above with respect to the first set of illustrative examples.

[0019] In a third set of illustrative examples, another apparatus for wireless communication in a UE is described. In one configuration, the apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to receive a first signal, the first signal including an indication of whether system information should be requested by the UE, and to obtain the system information according to the indication. In some examples, the instructions may also be executable by the processor to implement one or more aspects of the method for wireless communication described above with respect to the first set of illustrative examples.

[0020] In a fourth set of illustrative examples, a non-transitory computer-readable medium storing computer-executable code for wireless communication in a UE is described. In one configuration, the code may be executable by a processor to receive a first signal, the first signal including an indication of whether system information should be requested by the UE, and to obtain the system information according to the indication. In some examples, the code may also be used to implement one or more aspects of the method for wireless communication described above with respect to the first set of illustrative examples.

[0021] In a fifth set of illustrative examples, another method for wireless communication is described. In one configuration, the method may include transmitting a first signal, the first signal including an indication of whether system information is to be requested by the UE, and transmitting the system information according to the indication.

[0022] In some embodiments, the method may include receiving a request for system information in accordance with the instructions and transmitting the system information in response to the request. In some embodiments of the method, transmitting the system information may include transmitting the system information via a second signal in accordance with the instructions, the second signal being transmitted via broadcast or broad beam operation. In some embodiments, the method may include including in the first signal information indicating where the request for system information should be transmitted. In some embodiments, the method may include including in the first signal information indicating a predetermined channel over which the system information should be transmitted via broadcast or broad beam operation.

[0023] In some embodiments of the method, transmitting the system information may include transmitting the system information according to the instructions and transmission mode. In some embodiments, the method may include changing the transmission mode to be a broadcast or broad beam mode targeted to the cell edge and with fixed periodic scheduling. In some embodiments, the method may include changing the transmission mode to be a broadcast or broad beam mode targeted to the cell edge and with on-demand periodic scheduling triggered by a request for system information according to the instructions. In some embodiments, the method may include changing the transmission mode to be a broadcast or broad beam mode with on-demand, irregular scheduling triggered by a request for system information according to the instructions. In some embodiments, the method may include changing the transmission mode to be a unicast or narrow beam mode with on-demand, irregular scheduling triggered by a request for system information according to the instructions. In some embodiments, the method may include changing the transmission mode based on a network load or congestion condition. In some embodiments of the method, the first signal may be a synchronization signal.

[0024] In some embodiments, the method may include transmitting a first signal in a massive MIMO network using broad beam operation. In some of these examples, the method may include transmitting system information using broad beam or narrow beam operation according to the instructions and transmission modes described above.

[0025] In some embodiments, the method may include transmitting the first signal in the non-massive MIMO network using broadcast operation. In some of these examples, the method may include transmitting the system information using broadcast or unicast operation according to the instructions and transmission mode described above.

[0026] In some embodiments of the method, transmitting system information may include transmitting system information associated with available services to the UE in accordance with the instructions, wherein separate transmissions are used to transmit system information for different services and different configurations of the services. In some embodiments, the method may include receiving a request for system information for one or more services in accordance with the instructions, and transmitting system information for the one or more services in response to the request. In some embodiments, the method may include receiving multiple requests for system information for one or more services in accordance with the instructions, each request being from the UE and being for system information for a different service, and transmitting system information for the one or more services in response to the requests. In these examples, transmitting system information in response to the request may include transmitting system information for each of the one or more services in a joint transmission. Alternatively, transmitting system information in response to the request may include transmitting system information for each of the one or more services in a separate transmission.

[0027] In some embodiments, the indication may be a first indication, and the method may further include including in the first signal a second indication that system information for one or more services should be broadcast at one or more predetermined times and on one or more predetermined channels. In some embodiments, the indication may be a first indication, and the method may further include including in the first signal a second indication that system information for one or more services is available to be requested. In some of these examples, the method may include receiving one or more requests for system information for the one or more services in accordance with the first indication and the second indication. In some examples, the method may further include including with the first signal information indicating when and where the one or more requests for system information for the one or more services should be transmitted.

[0028] In some embodiments, the method may further include including in the system information information indicating one or more services for which the system information is valid. In some embodiments, the method may further include including in the system information information indicating a length of time for which the system information is valid, the system information for different services and different configurations of the services including different lengths of time. In some embodiments, the method may further include receiving one or more requests for system information for one or more services in accordance with the above instructions without including in the first signal a second indication of which services system information is available. In some embodiments, the method may further include receiving one or more requests for system information in accordance with the above instructions and identifying system information to be transmitted for different services based at least in part on transmission resources used by the one or more requests. In some embodiments, the method may further include modifying the above indication to indicate that the system information should be transmitted via either broadcast or broad beam operation or unicast or narrow beam operation.

[0029] In a sixth set of illustrative examples, another apparatus for wireless communication is described. In one configuration, the apparatus may include means for transmitting a first signal, the first signal including an indication of whether system information should be requested by the UE, and means for transmitting the system information in accordance with the indication. In some embodiments, the apparatus may further include means for receiving a request for system information in accordance with the indication, and means for transmitting the system information in response to the request. In some embodiments, the means for transmitting system information may include means for transmitting system information associated with available services to the UE in accordance with the indication, wherein separate transmissions are used to transmit system information for different services and different configurations of the services. In some examples, the apparatus may further include means for implementing one or more aspects of the method for wireless communication described above with respect to the fifth set of illustrative examples.

[0030] In a seventh set of illustrative examples, another apparatus for wireless communication is described. In one configuration, the apparatus may include a processor, a memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to transmit a first signal, the first signal including an indication of whether system information should be requested by a user equipment (UE), and to transmit the system information according to the indication. In some examples, the instructions may also be executable by the processor to implement one or more aspects of the method for wireless communication described above with respect to the fifth set of illustrative examples.

[0031] In an eighth set of illustrative examples, another non-transitory computer-readable medium storing computer-executable code for wireless communication is described. In one configuration, the code may be executable by a processor to transmit a first signal, the first signal including an indication of whether system information should be requested by the UE, and to transmit the system information according to the indication. In some examples, the code may also be used to implement one or more aspects of the method for wireless communication described above with respect to the fifth set of illustrative examples.

[0032] The foregoing has outlined rather broadly the features and technical advantages of examples according to the present disclosure in order that the following detailed description may be better understood. Additional features and advantages will be described below. The concepts and examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent structures do not depart from the scope of the appended claims. The nature of the concepts disclosed herein, both their organization and methods of operation, together with associated advantages, will be better understood from the following description when considered in conjunction with the accompanying figures. Each of the figures is provided for the purpose of illustration and description, and not as a definition of the limits of the claims.

[0033] A further understanding of the nature and advantages of the present disclosure may be realized by reference to the following drawings. In the accompanying drawings, similar components or features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a dash and a second label that distinguishes between the similar components. When only a first reference label is used herein, the description is applicable to any one of the similar components having the same first reference label, regardless of the second reference label. [Brief explanation of the drawings]

[0034] [Figure 1] FIG. 1 illustrates an example of a wireless communication system in accordance with various aspects of the present disclosure. [Figure 2] FIG. 1 illustrates an example of user equipment (UE) mobility within a wireless communication system, in accordance with various aspects of the present disclosure. [Figure 3A] FIG. 10 illustrates an exemplary transmission / reception timeline for a first base station, a second base station, a third base station, a fourth base station, a fifth base station, and a sixth base station, respectively, in accordance with various aspects of the present disclosure. [Figure 3B] FIG. 10 illustrates an exemplary transmission / reception timeline for a first base station, a second base station, a third base station, a fourth base station, a fifth base station, and a sixth base station, respectively, in accordance with various aspects of the present disclosure. [Figure 4] 1 is a swim lane diagram illustrating transmission by a base station of a synchronization signal, a master system information block (MSIB), and an alternative system information block (OSIB) in accordance with various aspects of the present disclosure. [Figure 5] FIG. 1 illustrates a Venn diagram of respective coverage areas of a 5G wireless communication network, a first neighboring radio access technology (RAT, e.g., neighboring RAT1), a second neighboring RAT (e.g., neighboring RAT2), and a third neighboring RAT (e.g., neighboring RAT3), according to various aspects of the present disclosure. [Figure 6] FIG. 10 is a swimlane diagram illustrating transmission of a synchronization signal, an MSIB, and an OSIB by a base station in accordance with various aspects of the present disclosure. [Figure 7] FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 8] FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 9] FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 10] FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 11] FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 12]FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 13] FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 14] FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 15] FIG. 1 is a block diagram of a UE for use in wireless communication, in accordance with various aspects of the present disclosure. [Figure 16] FIG. 1 is a block diagram of a base station for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 17] FIG. 1 is a block diagram of a base station for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 18] FIG. 1 is a block diagram of a base station for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 19] FIG. 1 is a block diagram of a base station for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 20] FIG. 1 is a block diagram of a base station for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 21] FIG. 1 is a block diagram of a base station for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 22] FIG. 1 is a block diagram of a base station for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 23] FIG. 1 is a block diagram of a base station for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 24A] 1 is a block diagram of a base station (e.g., a base station that forms part or all of an eNB) for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 24B]1 is a block diagram of a base station (e.g., a base station that forms part or all of an eNB) for use in wireless communications, in accordance with various aspects of the present disclosure. [Figure 25] FIG. 1 is a block diagram of a multiple-input multiple-output (MIMO) communication system including a base station and a UE, in accordance with various aspects of the present disclosure. [Figure 26] 1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 27] 1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 28] 1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 29] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 30] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 31] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 32] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 33] 1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 34] 1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 35] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 36] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 37]1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 38] 1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 39] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 40] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 41] 1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 42] 1 is a flowchart illustrating an example method for wireless communication in a UE, in accordance with various aspects of the present disclosure. [Figure 43] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 44] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 45] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. [Figure 46] 1 is a flowchart illustrating an example method for wireless communication in a base station, in accordance with various aspects of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0035] The described features may generally be implemented in a wireless communication system having a user equipment (UE)-centric network. The UE-centric network may, in some cases, be deployed as multiple base stations, with each of one or more base stations associated with several transceivers collocated with a base station server; as multiple base stations, with each of one or more base stations associated with several remote transceivers (e.g., several remote radio heads (RRHs)) located remotely from a base station server; as several zones, with each zone defined by the coverage area of ​​one or more cells or base stations; or a combination thereof. A wireless communication system having a UE-centric network may be advantageous in some respects in a time division duplex (TDD) system with a large antenna array, which may have limited coverage for broadcast channels (e.g., channels that broadcast synchronization signals and system information in a wireless communication system having a network-centric network). As described in this disclosure, a wireless communication system having a UE-centric network may dispense with broadcasting system information. A wireless communication system having a UE-centric network can also be advantageous in several ways, as the broadcasting of system information by base stations can contribute significantly to the power consumption of the base stations.

[0036] In one aspect of the present disclosure, for example, a wireless network may provide system information by fixed, periodic broadcast or broad-beam transmissions or in response to requests by UEs. The wireless network may broadcast (or broad-beam transmit) a synchronization signal that indicates to UEs within a cell or zone's coverage area that system information should be transmitted, for example, on a fixed, periodic schedule or in response to requests transmitted by one or more UEs. In an "on-demand" system in which UEs request system information transmission, the system information may be transmitted as periodic broadcast or broad-beam transmissions, as occasional broadcast or broad-beam transmissions, or as occasional unicast or narrow-beam transmissions.

[0037] In another aspect of the present disclosure, a wireless network may provide service-specific system information. The service-specific system information may be provided as a broadcast or upon receiving a request from a UE. In an on-demand system, the wireless network may, for example, broadcast (or broad-beam transmit) a synchronization signal that indicates to UEs within a coverage area of ​​a cell or zone that service-specific system information is available for the UE to request. The UE may then transmit one or more requests for service-specific system information and receive system information for the identified service. Alternatively, in a broadcast system, the wireless network may broadcast (or broad-beam transmit) a synchronization signal that, for example, indicates to UEs within a coverage area of ​​a cell or zone that the service-specific system information should be transmitted on a fixed, periodic schedule based on the corresponding service. Thus, a UE requesting system information for a given service can know from the synchronization signal one or more times during which the UE can listen to receive the service-specific system information. The service-specific system information may be transmitted jointly or in separate transmissions corresponding to the service.

[0038] In another aspect of the present disclosure, the wireless network may additionally provide system information to the UE. For example, the wireless network may transmit master system information, followed by one or more transmissions of other system information (e.g., non-master system information). The master system information may include, for example, system information that enables the UE to perform initial access of the network. The master system information or other system information may be broadcast, broad-beam transmitted, unicast, or narrow-beam transmitted to several UEs. In some cases, the master system information or other system information may be transmitted on a fixed, periodic schedule or in response to a request transmitted by one or more UEs. In various embodiments, the master system information and other system information may be transmitted in the same, similar, or different manners.

[0039] In yet another aspect of the present disclosure, for example, the wireless network may indicate when system information has changed or should be updated. In this manner, the UE need not update its stored system information every time system information is transmitted, but instead can update the stored system information "as needed." The UE may also initiate an update of its stored system information upon the occurrence of one or more events, such as a determination that the UE has moved a distance since the last time it updated its stored system information, or a determination that the UE has moved into a new zone.

[0040] The techniques described herein may be used for various wireless communication systems, such as Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single-Carrier Frequency Division Multiple Access (SC-FDMA) systems, and other systems. The terms "system" and "network" are often used interchangeably. A CDMA system may implement radio technologies such as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 encompasses IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and A are commonly referred to as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to as CDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. A TDMA system may implement a radio technology such as Global System for Mobile Communications (GSM). An OFDMA system may implement a radio technology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc. UTRA and E-UTRA are parts of the Universal Mobile Telecommunications System (UMTS). Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are newer releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization named "3rd Generation Partnership Project" (3GPP).CDMA2000 and UMB are described in documents from an organization named "3rd Generation Partnership Project 2 (3GPP2)." The techniques described herein may be used for the systems and radio technologies mentioned above, as well as other systems and radio technologies, including cellular (e.g., LTE) communications over shared radio frequency spectrum bands. However, while the following description describes LTE / LTE-A systems for illustrative purposes, and LTE terminology is used in much of the following description, the technology is applicable outside of LTE / LTE-A applications (e.g., to 5G networks or other next-generation communication systems).

[0041] The following description provides examples and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made in the function and arrangement of the described elements without departing from the scope of the present disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For example, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Also, features described with respect to some examples may be combined in other examples.

[0042] FIG. 1 illustrates an example of a wireless communication system 100 in accordance with various aspects of the present disclosure. The wireless communication system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130. The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The base stations 105 may interface with the core network 130 through backhaul links 132 (e.g., S1, etc.). The base stations 105 may perform radio configuration and scheduling for communications with the UEs 115 or may operate under the control of a base station controller (not shown). In various examples, the base stations 105 may communicate with each other either directly or indirectly (e.g., through the core network 130) through backhaul links 134 (e.g., X1, etc.), which may be wired or wireless communication links.

[0043] The base stations 105 can communicate wirelessly with the UEs 115 via one or more antennas. In some examples, the one or more antennas may include one or more base station antennas (and transceivers) collocated with the base station server and / or one or more RRH antennas (and transceivers) located remotely from the base station server. Each of the base stations 105 can provide communication coverage to a respective geographic coverage area 110. In some examples, the base stations 105 may be referred to as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB), a Home NodeB (HNB), a Home eNodeB, or some other suitable terminology. The geographic coverage area 110 of a base station 105 may be divided into sectors (not shown) that make up only a portion of the coverage area. The geographic coverage areas 110 of one or more base stations 105 may define zones of the wireless communication system 100. The wireless communication system 100 may include different types of base stations 105 (e.g., macrocell base stations or small cell base stations). There may be overlapping geographic coverage areas 110 for different technologies.

[0044] In some examples, the wireless communication system 100 may be or include an LTE or LTE-A network. The wireless communication system 100 may also be or include a next-generation network, such as a 5G wireless communication network. In LTE / LTE-A and 5G networks, the term evolved node B (eNB) may be used generally to refer to a base station 105, while the term UE may be used generally to refer to a UE 115. The wireless communication system 100 may be a heterogeneous LTE / LTE-A or 5G network in which different types of eNBs provide coverage to various geographic regions. For example, each eNB or base station 105 may provide communication coverage for a macro cell, a small cell, or other type of cell. The term “cell” is a 3GPP term that may be used to refer to a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc.) of a carrier or base station, depending on the context.

[0045] A macrocell may generally cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs 115 that have a service agreement with a network provider. Compared to a macrocell, a small cell may include a low-power base station that may operate in the same or a different frequency band (e.g., licensed, unlicensed, etc.) as the macrocell. Small cells may include picocells, femtocells, and microcells, according to various examples. A picocell, for example, may cover a small geographic area and allow unrestricted access by UEs 115 that have a service subscription with the network provider. A femtocell may also cover a small geographic area (e.g., a home) and may provide restricted access by UEs 115 that have an association with the femtocell (e.g., UEs 115 in a Closed Subscriber Group (CSG), UEs 115 for users in the home, etc.). An eNB for a macrocell may be referred to as a macro eNB. An eNB for a small cell may be referred to as a small cell eNB, pico eNB, femto eNB, or home eNB. An eNB may support one or multiple (e.g., two, three, four, etc.) cells.

[0046] A communication network that may accommodate some of the various disclosed examples may be a packet-based network operating according to a layered protocol stack, and data in the user plane may be IP-based. The radio link control (RLC) layer may perform packet segmentation and reassembly for communication over logical channels. The MAC layer may perform priority handling and multiplexing of logical channels onto transport channels. The MAC layer may also use HARQ to perform retransmissions at the MAC layer to improve link efficiency. In the control plane, a radio resource control (RRC) protocol layer may establish, configure, and maintain an RRC connection between the UE 115 and the base station 105. The RRC protocol layer may also be used for core network 130 support of radio bearers for user plane data. In the physical (PHY) layer, transport channels may be mapped to physical channels.

[0047] The UEs 115 may be dispersed throughout the wireless communication system 100, and each UE 115 may be fixed or mobile. The UEs 115 may also include or be referred to by those skilled in the art as mobile stations, subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobile terminals, wireless terminals, remote terminals, handsets, user agents, mobile clients, clients, or some other suitable terminology. The UEs 115 may be mobile phones, smartphones, personal digital assistants (PDAs), wireless modems, wireless communication devices, handheld devices, tablet computers, laptop computers, cordless phones, wireless local loop (WLL) stations, data cards, universal serial bus (USB) dongles, wireless routers, etc. The UEs 115 may be capable of communicating with various types of base stations and network equipment, including macro eNBs, small cell eNBs, relay base stations, etc. As the UE 115 moves within the wireless communication system 100, the UE 115 may move from cell to cell or from zone to zone (a zone comprising one or more cells). When the wireless communication system 100 is deployed as a UE-centric network, the UE 115 may move from cell to cell within a zone without physical channel reconfiguration, and the network provides data transfer services over the same radio resources despite the change in the UE's serving cell.

[0048] The wireless communication links 125 shown in the wireless communication system 100 may carry uplink (UL) transmissions from the UE 115 to the base station 105 or downlink (DL) transmissions from the base station 105 to the UE 115. Downlink transmissions may also be referred to as forward link transmissions, while uplink transmissions may also be referred to as reverse link transmissions. Each of the wireless communication links 125 may include one or more carriers, and each carrier may be a signal composed of multiple subcarriers (e.g., waveform signals of different frequencies) modulated in accordance with the various radio technologies described above. Each modulated signal may be transmitted on a different subcarrier and may carry control information (e.g., reference signals, control channels, etc.), overhead information, user data, etc. The wireless communication links 125 may transmit bidirectional communications using frequency division duplex (FDD) operation (e.g., using paired spectrum resources) or TDD operation (e.g., using unpaired spectrum resources). Frame structures for FDD (e.g., frame structure type 1) and TDD (e.g., frame structure type 2) may be defined.

[0049] In some embodiments of the wireless communication system 100, the base station 105 or the UE 115 may include multiple antennas to utilize antenna diversity schemes to improve communication quality and reliability between the base station 105 and the UE 115. Additionally or alternatively, the base station 105 or the UE 115 may utilize multiple-input multiple-output (MIMO) techniques (e.g., any MIMO that is not massive MIMO (e.g., multi-antenna MIMO and multi-user MIMO) techniques, or massive MIMO techniques) that may take advantage of a multipath environment to transmit multiple spatial layers carrying the same or different coded data.

[0050] The wireless communication system 100 may support operation on multiple cells or carriers, a feature that may be referred to as carrier aggregation (CA) or multi-carrier operation. A carrier may also be referred to as a component carrier (CC), layer, channel, etc. The terms “carrier,” “component carrier,” “cell,” and “channel” may be used interchangeably herein. A UE 115 may be configured with multiple downlink CCs and one or more uplink CCs for carrier aggregation. Carrier aggregation may be used with both FDD and TDD component carriers.

[0051] In some embodiments of the wireless communication system 100, the wireless communication system 100 may have a UE-centric network. On the network side, the base station 105 may broadcast a periodic synchronization (sync) signal. The UE 115 may receive the synchronization signal, acquire network timing from the synchronization signal, and transmit a pilot signal in response to acquiring the network timing. The pilot signal transmitted by the UE 115 may be simultaneously receivable by multiple cells (e.g., base stations 105) in the network. Each of the multiple cells may measure the strength of the pilot signal, and the network (e.g., one or more of the base stations 105, each communicating with the UE 115 via one or more centrally located transceivers and / or RRHs, and / or a central node in the core network 130) may determine a serving cell for the UE 115. As the UE 115 continues to transmit the pilot signal, the network may handover the UE 115 from one serving cell to another, with or without informing the UE 115. System information (SI) may be transmitted to the UEs 115 in a broadcast mode (e.g., where the base station 105 transmits SI regardless of whether the SI is requested or needed by any UEs 115 within the coverage area 110 of the base station 105) or in an on-demand mode (e.g., where the base station 105 transmits SI in response to receiving a request for SI from one or more UEs 115, which may be included in or be a pilot signal of the UEs 115). When transmitting SI in an on-demand mode, the base station 105 may avoid broadcasting the SI, which may save power.

[0052] 2 illustrates an example of UE mobility within a wireless communication system 200 in accordance with various aspects of the present disclosure. More specifically, FIG. 2 illustrates the UE 115-a as it moves to various points (e.g., points A, B, and C) within the coverage areas 110-a and 110-b of the respective first and second base stations 105-a and 105-b. In some examples, the UE 115-a may be an example of one or more aspects of the UE 115 described with reference to FIG. 1, and the first and second base stations 105-a and 105-b may be an example of one or more aspects of the base stations 105 described with reference to FIG. 1.

[0053] As an example, the UE 115-a may be powered on within the coverage area 110-a of the first base station 105-a and may perform initial acquisition of the SI within the coverage area 110-a of the first base station 105-a. In some examples, the UE 115-a may receive instances of a periodic synchronization signal from the first base station 105-a, determine from the synchronization signal when and where to listen for broadcasts of the SI by the first base station 105-a, and perform initial acquisition of the SI by listening to and receiving the SI broadcast by the first base station 105-a. In another example, the UE 115-a may receive an instance of a periodic synchronization signal from the first base station 105-a, determine from the synchronization signal when and where to listen for SI broadcast by the first base station 105-a and, in some cases, when and where to send a request for SI, send the request for SI, and perform initial acquisition of SI by listening to and receiving the broadcast of SI by the first base station 105-a. In yet another example, the UE 115-a may determine from the periodic synchronization signal received from the first base station 105-a that service-specific SI is available for reception either via broadcast or via request, and perform initial acquisition of the service-specific SI by either listening for the service-specific SI or requesting the service-specific SI.

[0054] While still at point A, UE 115-a may decide to reacquire the SI based on the expiration of the dynamic SI or based on the time elapsed since the SI was last acquired. UE 115-a may also reacquire the SI after receiving an instance of a synchronization signal at point A indicating that the SI has changed. In other embodiments, UE 115-a may not reacquire the SI at point A.

[0055] Upon moving from point A to point B, UE 115-a may decide to reacquire SI. UE 115-a may decide to reacquire SI based on, for example, its movement, the distance between point A and point B, the expiration of a dynamic SI, or the time elapsed since the SI was last acquired. UE 115-a may also reacquire SI after receiving an instance of a synchronization signal at point B indicating that the SI has changed. In other embodiments, UE 115-a may not reacquire SI at point B.

[0056] Upon moving from point B to point C and into the coverage area 110-b of the second base station 105-b, the UE 115-a may perform an initial acquisition of SI from the second base station 105-b. In other embodiments, the UE 115-a does not need to acquire SI from the second base station 105-b unless one of the reasons for re-acquiring SI occurs at point B. In some cases, SI may not be acquired in the coverage area 110-b because the first coverage area 110-a and the second coverage area 110-b are configured to operate as members of a common zone, such that data transfer services for the UE 115-a are provided by the network.

[0057] 2 illustrates that SI may be acquired during various UE mobility states and for various reasons. For example, SI may be acquired when the UE is not connected to a network (e.g., as part of the initial acquisition of SI). SI may also be acquired after the UE connects to a network and while the UE is stationary (e.g., because a timer or SI has expired, or because the network has indicated (e.g., at the instance of a synchronization signal or in a paging message) that the SI has changed). SI may also be acquired after the UE connects to a network and while the UE is moving (e.g., because the UE has moved to a new location, the UE has moved a distance from the previous location where the SI was acquired, or the UE has moved into the coverage area of ​​a new base station or cell, any of the reasons for which SI was reacquired while the UE was stationary).

[0058] 3A and 3B show example transmission / reception timelines 305, 320, 335, 350, 365, and 380 of a first base station, a second base station, a third base station, a fourth base station, a fifth base station, and a sixth base station, respectively, in accordance with various aspects of the present disclosure. The base station transmissions may be received and used by one or more UEs during initial SI acquisition (e.g., SI acquisition during system selection or movement to a new cell or zone) or during SI change acquisition (e.g., upon SI change or dynamic SI expiration). In some examples, the base stations may belong to different cells or zones of a wireless communication system, such as different cells or zones of the wireless communication system 100 or 200 described with reference to FIG. 1 or FIG. 2. In some examples, the first base station, the second base station, the third base station, the fourth base station, the fifth base station, and the sixth base station may be examples of one or more aspects of the base station 105 described with reference to FIG. 1.

[0059] As shown in Figures 3A and 3B, each of the base stations may transmit a periodic synchronization signal (Sync) 310, 325, 340, 355, 370, or 385. In the example of Figure 3A, each of the base stations also transmits a periodic, on-demand Master System Information Block (MSIB) 315, 330, 342, or 358. In some cases, instances of the synchronization signal and instances of the MSIB together may provide information equivalent to the information contained in the LTE / LTE-A Master Information Block (MIB), System Information Block 1 (SIB1), and SIB2. In the example of Figure 3B, each of the base stations transmits service-specific SIBs 375, 390.

[0060] In some embodiments, the synchronization signal transmitted by the base station may be common (e.g., not cell-specific) to multiple cells in an access network (e.g., multiple cells in a zone) and may be broadcast from each of the cells in the multiple cells (e.g., from each of multiple base stations in a cell) in the manner of a single frequency network (SFN). The synchronization signal need not include a cell identifier. In some embodiments, the synchronization signal may have a relatively short duration or may be transmitted relatively infrequently. For example, the synchronization signal may have a duration of one symbol and be transmitted once every 10 seconds. In other examples, the synchronization signal may be transmitted more frequently, such as once per radio frame. In some embodiments, an instance of the synchronization signal may carry several bits of information. More specifically, in some embodiments, an instance of the synchronization signal may include information such as information the UE may use to determine whether to request a later-transmitted MSIB, information the UE may use to determine when and where to request a later-transmitted MSIB (e.g., frequency and timing information for transmitting an MSIB transmission request), information the UE may use to determine when and where a later-transmitted MSIB may be received (e.g., channel, frequency, and / or timing information), information indicating when an MSIB changed, or information the UE may use to distinguish the cell or zone transmitting the synchronization signal from one or more other cells or zones (e.g., neighboring cells or zones). In some embodiments, an instance of the synchronization signal may include information the UE may use to determine whether to request a later-transmitted service-specific SIB, information the UE may use to determine when and where to request a later-transmitted service-specific SIB (e.g., frequency and timing information for transmitting a service-specific SIB transmission request), or information the UE may use to determine when and where a later-transmitted service-specific SIB may be received (e.g., channel, frequency, and / or timing information).

[0061] In some embodiments, the synchronization signal may indicate a PHY layer channel on which an MSIB or service-specific SIB transmission request should be transmitted, or may indicate a special PHY layer channel for transmission of an MSIB or service-specific SIB transmission request under some conditions. In some cases, the synchronization signal may also indicate how to transmit an MSIB or service-specific SIB transmission request (e.g., a format to be used when transmitting an MSIB or service-specific SIB transmission request), or how to transmit an MSIB or service-specific SIB transmission request under some conditions. In other embodiments, the synchronization signal may specify fewer parameters for transmission of an MSIB or service-specific SIB transmission request. However, this may require the base station to listen for an MSIB or service-specific SIB transmission request under more conditions (or always), which may affect the energy efficiency of the UE relay.

[0062] The UE may receive an instance of the synchronization signal and acquire access network timing based on the synchronization signal. In response to acquiring access network timing, the UE may transmit a pilot signal. The pilot signal may be simultaneously receivable by multiple cells in the access network (e.g., by multiple cells in a zone of the access network). In some embodiments, the pilot signal may include a spatial signature (e.g., a sounding reference signal (SRS)). In some embodiments, the pilot signal may be transmitted at an MSIB transmission request opportunity indicated by the instance of the synchronization signal. In some embodiments, the pilot signal may be transmitted using a predetermined random sequence or a random sequence generated by the UE, which may be used by the access network (e.g., a base station of the network) to temporarily identify the UE during an initial acquisition procedure. In some embodiments, the pilot signal may be or include an MSIB transmission request.

[0063] The MSIB 315, 330, 342, or 358 may indicate when and where the UE can establish a connection with the access network. The MSIB may include information such as information identifying the access network, cell, or zone, information indicating whether the UE is authorized (or should) use the access network, or information indicating how the UE can use the access network (e.g., information indicating how the UE can use the access network when the UE powers up or when the UE moves to a new cell or zone after detecting an out-of-service (OoS) or radio link failure (RLF) event). Information identifying the access network, cell, or zone may include a public switched telephone network (PLMN) identifier (ID), a tracking area code (TAC), a cell identifier (cell ID), or a zone identifier (zone ID). Information indicating whether the UE is authorized (or should) use the access network may include system selection information or access restriction information (e.g., radio quality information, congestion avoidance information, or closed subscriber group (CSG) information) for the cell or zone. The information indicating how the UE can use the access network may include access configuration information (e.g., random access channel (RACH) information, or UE timer and constant information). The MSIB may also include PHY layer configuration information such as physical random access channel (PRACH) information, physical downlink shared channel (PDSCH) information, physical downlink control channel (PDCCH) information, physical uplink shared channel (PUSCH) information, physical uplink control channel (PUCCH) information, and SRS information, or other information usable to access the PHY layer of a wireless communication system.

[0064] The service-specific SIBs 375, 390 may indicate when and where a UE can establish a connection with the access network for a particular service. A particular service may include, for example, an energy-efficient service, a reliable service, a low-latency service, a broadcast service, or a small data service. These services may require additional SI (e.g., SI not included in the MSIB) to enable the UE to access the network. For example, the Multimedia Broadcast Multicast Service (MBMS) in LTE may have additional configuration information related to accessing the MBMS in SIB 13. Additionally, as radio access technologies evolve, it may be desirable to not only enable the transmission of additional SI for specific services, but also to enable the transmission of different configurations of the same service-specific SI to improve the performance of different services. The additional service-specific SI may include, for example, information identifying the access network and cell (e.g., PLMN ID, TAC, or cell ID). The additional service-specific SI may also include information for the cell and access constraints (including radio quality, congestion avoidance, and CSG). The additional service-specific SI may further include information about access configurations (RACH, UE timers and constraints, and other 5G network equivalents).

[0065] For example, a service-specific SIB may contain information to enable more efficient access configuration and longer validity timers for SI in a wide area network (WAN) internet of everything (IOE), where low-power operation may be desirable since the IOE device may not connect to the network until after a long sleep period. Additionally, services such as WAN IOEs may include different information in their MSIBs to eliminate the need for the IOE device to read additional SI.

[0066] Turning now to the transmission / reception timeline 305 of the first base station (of FIG. 3A ), the first base station may transmit a periodic synchronization signal 310 as previously described. Upon receiving an instance of the synchronization signal, a UE that needs to perform initial acquisition may identify the access network associated with the first base station (and in some cases, information for distinguishing the first base station, its cell, or its zone from other base stations, cells, or zones), determine whether the UE can (or should) acquire the SI of the access network, and determine how the UE can acquire the SI of the access network. When determining how the UE can acquire the SI of the access network, the UE may determine, via signaling associated with the synchronization signal, that the first base station transmits an MSIB 315 in a broadcast (or broad-beam) transmission mode using fixed, periodic signaling. The UE may also identify from the synchronization signal a time for receiving the MSIB transmission. A UE that does not need to perform initial acquisition may determine from the synchronization signal whether the UE has moved to a new cell or a new zone. When the UE determines that it has moved to a new cell or new zone, the UE may use the information contained in the synchronization signal to obtain new or updated SI from the new cell or new zone.

[0067] Referring to the second base station transmission / reception timeline 320 (of FIG. 3A ), the second base station may transmit a periodic synchronization signal 325 as previously described. Upon receiving an instance of the synchronization signal, a UE needing to perform initial acquisition may identify the access network associated with the second base station (and in some cases, information for distinguishing the second base station, its cell, or its zone from other base stations, cells, or zones), determine whether the UE can (or should) acquire the SI of the access network, and determine how the UE can acquire the SI of the access network. When determining how the UE can acquire the SI of the access network, the UE may determine, via signaling associated with the synchronization signal, that the second base station transmits the MSIB 330 in an on-demand broadcast (or broad beam) transmission mode with periodic signaling (i.e., the second base station begins broadcast (or broad beam) transmission of the MSIB with periodic scheduling upon receiving an MSIB transmission request signal 332 from the UE). The UE may also determine from the synchronization signal when and where to transmit an MSIB transmission request and a time to receive the MSIB transmission. A UE that does not need to perform initial acquisition may determine from the synchronization signal whether the UE has moved to a new cell or a new zone. When the UE determines that the UE has moved to a new cell or a new zone, the UE may use the information contained in the synchronization signal to acquire new or updated SI from the new cell or new zone.

[0068] Referring to third base station transmission / reception timeline 335 (of FIG. 3A ), the third base station may transmit periodic synchronization signals 340 as previously described. Upon receiving an instance of the synchronization signal, a UE needing to perform initial acquisition may identify the access network associated with the third base station (and in some cases, information to distinguish the third base station, its cell, or its zone from other base stations, cells, or zones), determine whether the UE can (or should) acquire the SI of the access network, and determine how the UE can acquire the SI of the access network. When determining how the UE can acquire the SI of the access network, the UE may determine, via signaling associated with the synchronization signal, that the third base station transmits the MSIB 342 in an on-demand broadcast (or broad-beam) transmission mode with indefinite signaling (i.e., the third base station schedules the broadcast (or broad-beam) transmission of the MSIB upon receiving an MSIB transmission request signal 345 from the UE, and the UE may monitor a scheduling channel (e.g., PDCCH) for scheduling information (Sched.) 348 to determine when the MSIB will be transmitted). The UE may also identify from the synchronization signal when and where to transmit the MSIB transmission request. A UE that does not need to perform initial acquisition may determine from the synchronization signal whether the UE has moved to a new cell or a new zone. When the UE determines that the UE has moved to a new cell or a new zone, the UE may use information included in the synchronization signal to acquire new or updated SI from the new cell or new zone.

[0069] Referring to fourth base station transmission / reception timeline 350 (of FIG. 3A ), the fourth base station may transmit periodic synchronization signals 355 as previously described. Upon receiving an instance of the synchronization signal, a UE needing to perform initial acquisition may identify the access network associated with the fourth base station (and in some cases, information to distinguish the fourth base station, its cell, or its zone from other base stations, cells, or zones), determine whether the UE can (or should) acquire the SI of the access network, and determine how the UE can acquire the SI of the access network. When determining how the UE can acquire the SI of the access network, the UE may determine, via signaling associated with the synchronization signal, that the fourth base station transmits the MSIB 358 in a unicast (or narrow beam) transmission mode (i.e., that the fourth base station schedules the unicast (or narrow beam) transmission of the MSIB upon receiving an MSIB transmission request signal 360 from the UE, and that the UE may monitor a scheduling channel (e.g., PDCCH) for scheduling information (Sched.) 362 to determine when the MSIB will be transmitted). The UE may also identify from the synchronization signal when and where to transmit the MSIB transmission request. A UE that does not need to perform initial acquisition may determine from the synchronization signal whether the UE has moved to a new cell or a new zone. When the UE determines that the UE has moved to a new cell or a new zone, the UE may use information included in the synchronization signal to acquire new or updated SI from the new cell or new zone.

[0070] 3A , the base station transmits an MSIB 315, 330, 342, or 358. In some examples, the UE may receive the MSIB by monitoring a System Information Radio Network Temporary Identifier (SI-RNTI) on a common physical control channel (e.g., PDCCH), decoding a downlink assignment message associated with the SI-RNTI, and receiving the MSIB on a shared channel (e.g., PDSCH) according to information included in the downlink assignment message. Alternatively, when a Radio Network Temporary Identifier (RNTI; e.g., a Cell RNTI (C-RNTI) or a Zone RNTI (Z-RNTI)) is assigned for the UE, the UE may monitor the RNTI on a common physical control channel (e.g., PDCCH), decoding a downlink assignment message associated with the RNTI, and receiving the MSIB on a shared channel (e.g., PDSCH) according to information included in the downlink assignment message. In another alternative, the UE may monitor the SI-RNTI to receive broadcast SI, but the UE may also use an RNTI (e.g., a C-RNTI or a zone RNTI) dedicated to the UE to receive unicast SI.

[0071] When camped on a cell, the UE may decode at least a portion of each instance of the periodic synchronization signal transmitted by the cell to determine whether the information included in the MSIB has changed. Alternatively, the UE may decode at least a portion of every Nth instance of the periodic synchronization signal, or may decode at least a portion of an instance of the periodic synchronization signal upon the occurrence of one or more events. The decoded portion of a subsequent instance of the synchronization signal may include information (e.g., a modification flag or value tag) that may be set to indicate whether the SI of the cell has changed. Upon determining that the SI of the cell has changed (e.g., after receiving instance 310-a of synchronization signal 310 in transmit / receive timeline 305), the UE may request and / or receive an MSIB (e.g., MSIB 315-a) with the changed SI.

[0072] As a UE moves within the coverage area of ​​a wireless communications system, the UE may detect synchronization signals for different cells (or zones), such as synchronization signals for different cells (or coverage areas 110, 110-a, 110-b, or zones) described with respect to FIG. 1 or FIG. 2, or synchronization signals for different cells (or base stations or zones) described with respect to FIG. 3A. Upon detecting a synchronization signal for a cell or zone, the UE may compare a cell global identity (CGI) (or base station identity code (BSIC) or zone identity) corresponding to the cell (or base station or zone) from which the UE last obtained SI with the CGI (or BSIC or zone identity) associated with the synchronization signal to determine whether the UE has detected a new synchronization signal (e.g., a synchronization signal for a different cell, base station, or zone).

[0073] On-demand transmission of the MSIB may be initiated by the UE (e.g., during initial access) or by the access network (e.g., when information included in the MSIB changes or when a dedicated SIB is transmitted). In some cases, a base station transmitting and receiving signals according to one of the transmit / receive timelines 305, 320, 335, or 350 may switch transmit / receive modes, thereby switching from one of the transmit / receive timelines to the other of the transmit / receive timelines. This switching may occur based on, for example, network load or congestion conditions. In some embodiments, the base station may additionally or alternatively switch between an “on-demand unicast (or narrow beam)” mode and an “always-on broadcast (or broad beam)” mode for MSIB transmission. In some examples, the base station may signal the mode or modes in which it is operating in a periodic synchronization signal.

[0074] Turning now to the transmission / reception timeline 365 of the fifth base station (of FIG. 3B ), the fifth base station may transmit a service-specific periodic synchronization signal 370. The service-specific periodic synchronization signal 370 may be an example of the synchronization signals 310, 325, 340, 355, except that it may include an indication that service-specific SI is available. The service-specific periodic synchronization signal 370 may also include information about which services' service-specific SI is available. In addition, the service-specific periodic synchronization signal 370 may include information about a schedule of when service-specific SI for different services may be requested or transmitted. As an example, a service-specific SI may not be transmitted in every synchronization signal period. A synchronized MBMS service may only require service-specific SIBs to be transmitted, for example, on the order of a few seconds, and therefore may not be available during every synchronization signal period. Upon receiving an instance of the synchronization signal, the UE may determine that it needs one or more of the available service-specific SI. In accordance with the service-specific periodic synchronization signal 370, the UE may transmit a SIB transmission (Tx) request 372. The UE may transmit a SIB Tx request 372-a for transmission of SI for a particular service (e.g., service 1), followed by a SIB Tx request 372-b for transmission of SI for a different particular service (e.g., service 2). In response to receiving the SIB Tx requests 372, one or more base stations may transmit service-specific SIBs 375 to the UE. The fifth base station may transmit the service-specific SIB 375-a in response to the SIB Tx request 372-a and may also transmit the service-specific SIB 375-b in response to the SIB Tx request 372-b. Alternatively, the fifth base station may broadcast the service-specific SIB 375 without waiting for the SIB Tx request 372. In this alternative, the service-specific periodic synchronization signal 370 may indicate when and which resources the UE may listen to receive the service-specific SIB 375.

[0075] Referring to the sixth base station transmission / reception timeline 380 (of FIG. 3B ), the sixth base station may transmit a service-specific periodic synchronization signal 385. The service-specific periodic synchronization signal 385 may be one example of the synchronization signals 310, 325, 340, 355, except that it may include an indication that service-specific SI is available. However, the service-specific periodic synchronization signal 385 may not indicate the actual service for which SI is available. Instead, in the transmission / reception timeline 380, the UE is required to explicitly identify the service for which SI is desired in the SIB Tx request 388. The service-specific synchronization signal 385 may include information regarding when and on which resources the UE may transmit the SIB Tx request 388. Thus, upon receiving an instance of the synchronization signal, the UE may determine that it requires one or more of the available service-specific SI. In accordance with the service-specific periodic synchronization signal 385, the UE may transmit a SIB Tx request 388 specifying the requested SI. In response to receiving the SIB Tx request 388, the sixth base station may transmit service-specific SIBs 390 to the UE. The service-specific SIBs 390 may be transmitted together or jointly in a single transmission or may be transmitted separately.

[0076] Based on the service indicated in either the service-specific periodic synchronization signal 370, 385 or the SIB Tx request 372, 388, the base station may transmit a service-specific SIB 375, 390 to the UE. The service-specific SIB 375, 390 may include service-specific configurations, such as SI parameters that are specifically configured to improve the service or meet service requirements. For example, the service-specific configurations may include a validity timer or SI read requirements that require the IOE device to reacquire SI after the IOE device wakes up from power saving mode (PSM) or deep sleep. For example, the IOE device may acquire an SI with a particular value tag and then transition to PSM for an extended period of time (e.g., as a result of the device being an IOE device). By the time the IOE device wakes up, the SI may have changed more than once. In practice, the SI may even change a number of times equal to the number of available values ​​for the SI value tag, meaning that the SI acquired by the IOE device may happen to have the same value tag as the SI detected by the IOE device when the IOE device powers up. If the IOE device relies on the SI value tag to determine whether to acquire an updated SI, the IOE device may determine that a new SI should not be acquired. However, a validity timer or SI read requirement may be used to ensure that the IOE device acquires an updated SI, even if the SI value tag indicates otherwise. For example, the validity timer or SI read requirement may require the IOE device to reacquire the SI after the expiration of a specified time, which, in one example, may be equal to the IOE device's PSM time. Alternatively, the validity timer may be received as part of the service-specific configuration of the service-specific SIB 375, 390. In this case, the validity timer may be set to a length of time that requires the IOE device to reacquire the SI at least once during the wraparound of each SI value tag. Thus, if an operator changes the SI every 10 minutes and the SI value tag ranges from 0 to 31, the validity timer may be set to 320 minutes.The validity timer may also be based on other factors. The validity timer or SI reading requirements may be conveyed to the IOE device as part of the service-specific configuration in the service-specific SIB 375, 390.

[0077] As an example, in some LTE standards, a UE may consider a stored SI to be invalid three hours after the moment the SI is confirmed to be valid. While some exceptions may apply in LTE (e.g., csg-PhysCellIdRange, but this exception is due to the fact that updated SI may not be available if the UE is not camped on a CSG cell), the three-hour requirement may not be appropriate for many devices, including IOE devices that may enter PSM or whose SI value tags cycle on different frequencies. Therefore, for WAN IOE devices, the validity timer may be extended or shortened for SI related to the WAN IOE network.

[0078] The service-specific SIBs 375, 390 may also include service-specific information, such as service-specific parameters, such as parameters defined for MBMS. In a WAN IOE device, the service-specific configuration may be contained in a single SIB so that the IOE device does not need to send multiple requests to additionally receive any required SI.

[0079] Additionally, when multiple service-specific SIs corresponding to multiple services are supported, the network may use different transmission modes to support the transmission of the SI for each service. Thus, for example, the WAN IOE SI may be broadcast periodically, while the nominal SI may be transmitted on demand.

[0080] In an on-demand scenario, when a UE requests SI for more than one service in a SIB Tx request 372, 388, the corresponding base station may either provide a separate SI for each service or provide a common SI for all desired services; for example, when providing a common SI, the base station may apply the most restrictive configured value for the parameter based on the service requirements for each requested service.

[0081] In addition to the periodic or on-demand MSIBs, the base station may transmit one or more periodic or on-demand Other SIBs (OSIBs). The OSIBs may contain information equivalent to that contained in one or more LTE / LTE-A SIBs other than SIB1 or SIB2 (e.g., information to enable an operator to manage intra- or inter-Radio Access Technology (RAT) system selection, information for a UE to discover the availability and configuration of one or more services). One exemplary transmission of an OSIB is shown in FIG. 4.

[0082] 4 is a swimlane diagram 400 illustrating transmission of a synchronization signal, an MSIB, and an OSIB by a base station 105-c in accordance with various aspects of the present disclosure. FIG. 4 also illustrates requesting and receiving the MSIB and OSIB by a UE 115-b performing initial acquisition of an SI for an access network. In some examples, the base station may incorporate one or more aspects of the base station described with respect to FIG. 1 or FIG. 2. Similarly, the UE 115-b may incorporate one or more aspects of the UE 115 described with respect to FIG. 1 or FIG. 2.

[0083] At 405, the base station 105-c may transmit a periodic synchronization signal instance, as described with respect to FIG. 3A. The UE 115-b may receive the synchronization signal instance, process the synchronization signal instance at block 410, determine that the UE 115-b needs to transmit an MSIB transmission request, and obtain the MSIB from the base station 105-c at 415. The UE 115-b may also determine from the synchronization signal instance when and where to transmit the MSIB transmission request and when and where to expect transmission of the MSIB by the base station 105-c.

[0084] At 420, the base station 105-c may transmit an MSIB. The UE 115-b may receive the MSIB and process the information included in the MSIB at block 425. The UE 115-b may also optionally prepare an OSIB transmission request. In some examples, an OSIB transmission request may be prepared (e.g., at block 425) and transmitted (e.g., at 430) when the UE 115-b has not previously acquired SI from the cell or zone in which the base station 105-c is operating, or when cached SI for the cell or zone has expired, or when the UE determines that the SI for the cell or zone has changed (e.g., from a synchronization signal, from information in an MSIB signaling a change in SI, or from a paging message), or when the UE determines (e.g., during RRC_IDLE) that it is in a location where new SI can be provided (e.g., a location where new neighbor cell list equivalent information can be provided, or a location where new Global Positioning System (GPS) assistance information can be provided). In some cases, the OSIB transmission request may indicate which OSIB information is requested. For example, the UE 115-b may indicate in the OSIB transmission request which SI (e.g., which type of SI or which SIB) the UE wants to receive. In some examples, a single OSIB transmission request 430 may be transmitted, and the single OSIB transmission request 430 may indicate one or more elements of the other SI that the UE wants to receive (e.g., a binary value may be set to true for each element of the other SI that the UE wants to receive). In other examples, the UE 115-b may request several types of other SI in different OSIB transmission requests, and the UE may transmit multiple OSIB transmission requests to the base station.

[0085] The base station 105-c may receive the OSIB transmission request (or multiple OSIB transmission requests) and prepare one or more OSIBs in block 435 for transmission to the UE in 440 or 445. In some embodiments, the base station may prepare one or more OSIBs including the SI requested by the UE in the OSIB transmission request. Additionally or alternatively, the base station 105-c (and / or another network node with which the base station communicates) may determine which SI to transmit to the UE 115-b in the OSIB. The base station 105-c and / or other network node may determine which SI to transmit to the UE 115-b based on, for example, UE identification information, UE type, capability information the base station has obtained for the UE, or other information known about the UE (and that may be obtained from the UE). In this manner, the amount of SI transmitted to the UE 115-b can be optimized, which may be useful for saving power, freeing up resources, etc.

[0086] As previously indicated, an OSIB may contain information equivalent to information contained in one or more LTE / LTE-A SIBs other than SIB1 or SIB2 (e.g., information to enable an operator to manage intra- or inter-RAT system selection, information for a UE to discover the availability and configuration of one or more services). The information contained in an OSIB may be numbered and organized based on SI to enable a base station to deliver information to a UE based on a subset of UE capabilities, based on UE capabilities, or based on UE service requirements (e.g., a base station may not deliver MBMS information to a UE when the UE is not enabled to use the MBMS service). In some cases, the information contained in an OSIB may be numbered and organized the same as or similar to information contained in an LTE / LTE-A SIB.

[0087] The information included in the OSIB may be organized so that it can be efficiently received or processed by the UE. For example, the information may be organized so that the UE reads the information as infrequently as possible. In some embodiments, the information may be organized based on the scope of the information, whether the information applies system-wide, within a constellation, per cell, or per zone, the length of time the information remains valid (e.g., validity time), or whether the information is semi-static or dynamic. When the information is highly dynamic, the information may be organized so that it can be transmitted with low latency.

[0088] On-demand transmission of an OSIB may be initiated by the UE (e.g., during initial access) or by the access network (e.g., when information contained in the OSIB changes or when a dedicated SIB is transmitted).

[0089] As previously described, a base station can, in some cases, switch between "on-demand unicast (or narrow beam)" mode, "always-on broadcast (or broad beam)" mode, and "on-demand broadcast (or broad beam)" mode for MSIB transmission. A base station can also switch between "on-demand unicast (or narrow beam)" mode, "always-on broadcast (or broad beam)" mode, and "on-demand broadcast (or broad beam)" mode for OSIB transmission. In "always-on broadcast (or broad beam)" OSIB transmission, the OSIB transmission schedule can be signaled in the MSIB transmission.

[0090] In some cases, the UE may receive and process the MSIB or OSIB based on a change in the UE's location. In some cases, the MSIB or OSIB may be received and processed after transmitting a respective MSIB transmission request or OSIB transmission request. In this regard, FIG. 5 illustrates a Venn diagram 500 of the coverage areas of each of a first zone 505, a second zone 510, a third zone 515, and a fourth zone 520. In some embodiments, according to various aspects of the present disclosure, the first zone 505 may include a 5G wireless communication network, the second zone 510 may include a first neighboring RAT (e.g., neighboring RAT1), the third zone 515 may include a second neighboring RAT (e.g., neighboring RAT2), and the fourth zone 520 may include a third neighboring RAT (e.g., neighboring RAT3). By way of example, the 5G wireless communication network may incorporate aspects of the wireless communication system 100 or 200 described with respect to FIG. 1 or FIG. 2. Each of the first neighboring RAT, the second neighboring RAT, and the third neighboring RAT may also incorporate aspects of wireless communication system 100 or 200. The 5G wireless communication network, the first neighboring RAT, the second neighboring RAT, and the third neighboring RAT may also take different forms.

[0091] When the UE initially gains access to the 5G wireless communication network in the first zone 505, or as the UE moves within the 5G wireless communication network, the UE may acquire SI for a first neighboring RAT, a second neighboring RAT, or a third neighboring RAT. In some cases, the UE may use distance-based SI acquisition to acquire SI for the neighboring RATs. The UE may utilize distance-based SI acquisition by determining (e.g., calculating) the distance between the UE's current location and the UE's location the last time the UE acquired neighboring RAT SI. When the determined distance exceeds a threshold distance, the UE may initiate an SI acquisition procedure (e.g., the UE may receive an OSIB including the neighboring RAT SI, or the UE may transmit an OSIB transmission request in which the UE requests the neighboring RAT SI). The threshold distance may be configured by the network and may be indicated in the MSIB (e.g., as part of the measurement configuration indicated in the MSIB).

[0092] In some embodiments, distance-based SI acquisition may be utilized per neighboring RAT. In other embodiments, distance-based SI acquisition may be utilized per collective neighboring RAT.

[0093] In some cases, the UE may receive and process the MSIB or OSIB based on a change in SI signaled in a periodic synchronization signal. In some cases, the MSIB or OSIB may be received and processed after transmitting the respective MSIB transmission request or OSIB transmission request.

[0094] FIG. 6 is a swimlane diagram 600 illustrating transmission of a synchronization signal, an MSIB, and an OSIB by a base station 105-d in accordance with various aspects of the present disclosure. FIG. 6 also illustrates requesting and receiving the MSIB and OSIB by a UE 115-c performing a system information update. In some examples, the base station 105-d may incorporate one or more aspects of the base station 105 described with respect to FIG. 1, FIG. 2, or FIG. 4. Similarly, the UE 115-c may incorporate one or more aspects of the UE 115 described with respect to FIG. 1, FIG. 2, or FIG. 4.

[0095] At 605, the base station 105-d may transmit an instance of a periodic synchronization signal or a paging message as described with respect to Figure 3A. The instance of the synchronization signal or paging message may include information (e.g., a modification flag or value tag) indicating that the SI for the cell that includes the base station has changed.

[0096] In some embodiments, the synchronization signal or paging message instance may include a general indicator (e.g., a modification flag) that the SI has changed. The general indicator or modification flag may include, for example, a counter value that is incremented when the SI changes, or a Boolean variable (e.g., a binary value) that is set to true (e.g., logic “1”) when the SI contained in the MSIB changes (or when the network expects the UE to reacquire the MSIB) or set to false (e.g., logic “0”) when the SI contained in the MSIB has not changed (or when the network does not expect the UE to reacquire the MSIB). The synchronization signal or paging message instance may additionally or alternatively indicate whether some element of the SI has changed. For example, the synchronization signal or paging message instance may indicate whether the SI for a service such as a Public Warning System (PWS; e.g., Earthquake and Tsunami Warning System (ETWS) or Commercial Mobile Alert System (CMAS)) has changed, which may simplify decoding and improve battery life when such information changes more frequently.

[0097] The UE 115-c may receive the instance of the synchronization signal or paging message and process the instance of the synchronization signal or paging message in block 610 (e.g., compare a counter value associated with the synchronization signal or paging message with a previously received counter value, or determine whether a modification flag is set to true or false), determine that the SI for the cell or zone that includes the base station has changed, and (in some cases) determine that the changed SI is associated with the UE. The UE may also determine that the UE needs to transmit an MSIB transmission request and obtain an MSIB that includes the changed SI from the base station in 615. The UE may also determine from the instance of the synchronization signal or paging message when and where to transmit the MSIB transmission request and when and where to expect transmission of the MSIB by the base station.

[0098] At 620, the base station 105-d may transmit an MSIB. In some cases, the MSIB may include information indicating whether other SIs have changed. For example, the MSIB may include a general indicator (e.g., a modification flag) that other SIs have changed. The general indicator or modification flag may include, for example, a counter value that is incremented when an SI included in the OSIB changes, or a Boolean variable (e.g., a binary value) that is set to true (e.g., a logical "1") when an SI included in the OSIB changes (or when the network expects the UE to reacquire the OSIB) or set to false (e.g., a logical "0") when an SI included in the OSIB has not changed (or when the network does not expect the UE to reacquire the OSIB). The MSIB may also, or alternatively, indicate whether some element of the other SI has changed. For example, the MSIB may include a value tag for each type of SI, or for each equivalent LTE / LTE-A SIB (e.g., a first Boolean variable that is set to true or false to indicate whether the SI for an MBMS service has changed, a second Boolean variable that is set to true or false based on whether the SI for a PWS service (e.g., a CMAS service or an ETWS service) has changed, etc.).

[0099] The UE 115-c may receive the MSIB and process the information included in the MSIB at block 625. The UE may use the information indicating which other SIs useful to the UE (e.g., SIs monitored by the UE) have changed to determine whether an OSIB needs to be requested because it has changed. For example, the UE may compare an OSIB counter value included in the MSIB with a previously received OSIB counter value, or determine whether an OSIB modification flag is set to true or false, or compare a value tag for one or more monitored elements of the other SI with a previously received value tag for one or more monitored elements of the other SI to determine whether an OSIB needs to be requested. When the other SIs useful to the UE have not changed, the UE does not need to send an OSIB transmission request. However, when the other SIs useful to the UE have not changed, the UE may prepare (e.g., at block 625) and transmit (e.g., at 630) an OSIB transmission request. In some cases, the OSIB transmission request may be a generic request (e.g., a request to have the base station return all other SIs or a request that allows the base station to return any SIs that the base station deems useful to the UE). In other cases, the OSIB transmission request may indicate which OSIB information is requested. For example, the UE may indicate in the OSIB transmission request which SI (e.g., which type of SI or which SIB) the UE wants to receive.

[0100] The base station 105-d may receive the OSIB transmission request and prepare one or more OSIBs in block 635 for transmission to the UE in 640 or 645. In some embodiments, the base station may prepare an OSIB including the SI requested by the UE in the OSIB transmission request. Additionally or alternatively, the base station (and / or another network node with which the base station communicates) may determine which SI to transmit to the UE in the OSIB. The base station and / or other network node may determine which SI to transmit to the UE based on, for example, UE identity information, UE type, capability information the base station has obtained for the UE, or other information known about the UE (and that may be obtained from the UE). In this manner, the amount of SI transmitted to the UE can be optimized, which may be useful for saving power, freeing up resources, etc.

[0101] The table below provides an example allocation of SI to MSIBs and OSIBs in a 5G wireless communication system.

[0102] [Table 1]

[0103] Although each of Figures 4-6, and to some extent the remainder of this disclosure, primarily focuses on the transmission of an MSIB or OSIB, any number of MSIBs or OSIBs may be transmitted individually or collectively in response to a single MSIB transmission request and / or OSIB transmission request, or in response to multiple MSIB transmission requests and / or OSIB transmission requests. In some cases, master system information may be distributed among one or more of the MSIBs, MTC_SIBs, or other SIBs carrying master information. In some cases, other system information may be distributed among one or more of OSIB1 carrying neighbor cell / zone information, OSIB2 carrying MBMS-related information, OSIB3 carrying PWS-related information, or other SIBs carrying other information. An MSIB or OSIB may also include one or more elements. When an SI changes, a modification flag or value tag may be transmitted or received, for example, for each MSIB, for each element within an MSIB, for each OSIB, or for each element within an OSIB.

[0104] 7 shows a block diagram 700 of a UE 115-d for use in wireless communication in accordance with various aspects of the present disclosure. The UE 115-d may be an example of one or more aspects of the UE 115 described with respect to FIGS. 1-6. The UE 115-d may also be or include a processor. The UE 115-d may include a UE receiver module 710, an SI acquisition module 720, or a UE transmitter module 730. The SI acquisition module 720 may include an SI acquisition mode module 735, a UE SI request module 740, or an SI receive module 745. Each of these modules may be in communication with each other.

[0105] The modules of the UE 115-d, individually or collectively, may be implemented using one or more application-specific integrated circuits (ASICs) adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, field programmable gate arrays (FPGAs), systems-on-chips (SoCs), or other semi-custom ICs) that can be programmed in any manner known in the art may be used. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0106] In some examples, the UE receiver module 710 may include at least one radio frequency (RF) receiver. The UE receiver module 710 or RF receiver may be used to receive various types of data or control signals (i.e., transmissions) over one or more communication links of a wireless communication system, such as one or more communication links of the wireless communication system 100 described with reference to FIG. 1. As an example, the UE receiver module 710 may be used to receive periodic synchronization signals, as described with reference to FIGS. 3A, 3B, and 4. The UE receiver module 710 may also be used to receive various signals, including one or more forms of SI, as also described with reference to FIGS. 3A, 3B, and 4. As described in more detail below, reception and processing of synchronization and SI signals (e.g., the periodic synchronization signals 310, 325, 340, or 355 of FIG. 3A and the broadcast MSIBs 315, 330, 342, or unicast MSIBs 358 of FIG. 3A) may additionally be assisted through the SI acquisition module 720.

[0107] In some examples, the UE transmitter module 730 may include at least one RF transmitter. The UE transmitter module 730 or RF transmitter may be used to transmit various types of data or control signals (i.e., transmissions) over one or more communication links of a wireless communication system, such as one or more communication links of the wireless communication system 100 described with respect to FIG. 1. By way of example, as described with respect to FIG. 3A , the UE transmitter module 730 may be used to transmit MSIB transmission request signals 332, 345, 360. Transmission of the MSIB transmission request signals 332, 345, 360 may additionally be assisted through, for example, the SI acquisition module 720, as described in more detail below.

[0108] The SI acquisition module 720 may be used to manage one or more aspects of wireless communications for the UE 115-d. Specifically, in the UE 115-d, the SI acquisition module 720 may be used to assist in acquiring SI from the base station 105 in accordance with certain aspects of the embodiments described above. The SI acquisition module 720 may include an SI acquisition mode module 735, a UE SI request module 740, or an SI reception module 745.

[0109] The SI acquisition mode module 735 may be used by the UE 115-d to assist the UE 115-d in receiving periodic synchronization signals 310, 325, 340, 355, for example, as shown in Figures 3A, 3B, and 4. The received periodic synchronization signals 310, 325, 340, 355 may indicate to the UE 115-d whether the UE 115-d should transmit a request signal, such as an MSIB transmission request signal 332, 345, 360, for example, to receive transmissions of SI. For example, the UE 115-d may receive the periodic synchronization signal 310 that indicates to the UE 115-d that SI may be broadcast by the base station 105, independent of any request transmitted by the UE 115-d. In this case, the SI acquisition mode module 735 may determine that no request is necessary for the UE 115-d to receive SI. However, in another example, the UE 115-d may receive periodic synchronization signals 325, 340, 355, each of which may indicate that the UE 115-d should transmit a request for SI (e.g., in the form of MSIB transmission request signals 332, 345, 360) in order to receive the SI. In this case, the SI acquisition mode module 735 may determine that a request is necessary for the UE 115-d to receive the SI. Thus, the SI acquisition mode module 735 may be configured to determine whether the UE 115-d is operating in a network having a broadcast SI mode or a network having an on-demand SI mode.

[0110] If the UE 115-d is operating in a network using an on-demand SI mode, which means the UE 115-d should transmit a request to receive SI, the UE SI request module 740 may be used to assist in creating such a request. As an example, the UE SI request module 740 may be used to assemble any one of the MSIB transmission request signals 332, 345, 360 of FIG. 3A. The UE SI request module 740 may use information included with the periodic synchronization signals 325, 340, 355 to determine how to assemble the MSIB transmission request signals 332, 345, 360. For example, the periodic synchronization signals 325, 340, 355 may include information indicating where the MSIB transmission request signals 332, 345, 360 should be transmitted, as well as the timing of such signals.

[0111] The SI receiving module 745 may be used to assist in receiving SI transmitted to the UE 115-d. The SI may be transmitted as a broadcast without requiring a request transmitted by the UE 115-d. In this example, the SI acquisition mode module 735 may indicate to the SI receiving module 745 that the SI should be received via broadcast. The SI receiving module 745 may then use information included with the periodic synchronization signal 310, such as a predetermined channel or timing of the broadcast of the SI, to assist in receiving the SI. In another example, the SI may be transmitted as either a broadcast or a unicast in response to a request transmitted by the UE 115-d. In these examples, the SI acquisition mode module 735 may indicate to the SI receiving module 745 that the SI should be received as either a broadcast or a unicast in response to the request. The SI receiving module 745 may then use information included with the periodic synchronization signal 325, 340, 355, such as a predetermined channel or timing of the broadcast or unicast of the SI, to assist in receiving the SI.

[0112] FIG. 8 shows a block diagram 800 of a UE 115-e for use in wireless communications, according to various examples. The UE 115-e may be an example of one or more aspects of the UE 115 described with respect to FIGS. 1-7. The UE 115-e may include a UE receiver module 710-a, an SI acquisition module 720-a, and / or a UE transmitter module 730-a, which may be examples of corresponding modules of the UE 115-d (of FIG. 7). The UE 115-e may also include a processor (not shown). Each of these components may be in communication with one another. The SI acquisition module 720-a may include an SI acquisition mode module 735-a, a UE SI request module 740-a, and / or an SI reception module 745-a. The SI acquisition mode module 735-a may further include a synchronization signal reception module 805 and / or an SI acquisition mode determination module 810. UE receiver module 710-a and UE transmitter module 730-a may perform the functions of UE receiver module 710 and UE transmitter module 730, respectively, of FIG.

[0113] The modules of the UE 115-e may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0114] The SI acquisition mode module 735-a may include a synchronization signal reception module 805 and / or an SI acquisition mode determination module 810. The synchronization signal reception module 805 may be used by the UE 115-e to assist the UE 115-e in receiving periodic synchronization signals 310, 325, 340, 355, for example, as shown in Figures 3A, 3B, and 4. The received periodic synchronization signals 310, 325, 340, 355 may indicate to the UE 115-e whether the UE 115-e should transmit a request signal, such as an MSIB transmission request signal 332, 345, 360, for example, to receive transmissions of SI. Thus, the SI acquisition mode determination module 810 may be used to determine whether the SI acquisition mode is fixed or on-demand from the received periodic synchronization signals 310, 325, 340, 355. For example, the UE 115-e may receive, via the synchronization signal receiving module 805, a periodic synchronization signal 310 indicating to the UE 115-e that SI may be broadcast by the base station 105, regardless of any request transmitted by the UE 115-e. In this case, the SI acquisition mode determination module 810 may determine that a request is not required for the UE 115-e to receive SI. However, in another example, the UE 115-e may receive, via the synchronization signal receiving module 805, periodic synchronization signals 325, 340, 355, each of which may indicate that the UE 115-e should transmit a request for SI (e.g., in the form of MSIB transmission request signals 332, 345, 360) in order to receive the SI. In this case, the SI acquisition mode determination module 810 may determine that a request is required for the UE 115-e to receive SI. Thus, the SI acquisition mode determination module 810 may be configured to determine whether the UE 115-e is operating in a network having a fixed broadcast SI mode or an on-demand SI mode.

[0115] When the UE 115-e is operating in a network using an on-demand SI mode, which means the UE 115-e should transmit a request to receive SI, the UE SI request module 740-a may be used to assist in creating such a request. As an example, the UE SI request module 740-a may be used to assemble any one of the MSIB transmission request signals 332, 345, 360 of FIG. 3A. The UE SI request module 740-a may use information included with the periodic synchronization signals 325, 340, 355 to determine how to assemble the MSIB transmission request signals 332, 345, 360. For example, the periodic synchronization signals 325, 340, 355 may include information indicating where the MSIB transmission request signals 332, 345, 360 should be transmitted, as well as the timing of such signals.

[0116] The SI reception module 745-a may be used to assist in receiving SI transmitted to the UE 115-e. The SI may be transmitted as a broadcast without requiring a request sent by the UE 115-e. In this example, the SI acquisition mode module 735-a may indicate to the SI reception module 745-a that the SI should be received via broadcast. The SI reception module 745-a may then assist in receiving the SI using information included with the periodic synchronization signal 310, such as a predetermined channel or timing of the broadcast of the SI. The UE 115-e may receive the SI, in some examples, by monitoring the SI-RNTI on a common physical control channel (e.g., PDCCH), decoding a downlink assignment message associated with the SI-RNTI, and receiving the SI on a shared channel (e.g., PDSCH).

[0117] In another example, the SI may be transmitted as either a broadcast or a unicast in response to a request sent by the UE 115-e. In these examples, the SI acquisition mode module 735-a may indicate to the SI reception module 745-a that the SI should be received as either a broadcast or a unicast in response to the request. The SI reception module 745-a may then use information included with the periodic synchronization signal 325, 340, 355, such as a predetermined channel or timing of the broadcast or unicast of the SI, to assist in receiving the SI. The UE 115-e, in some examples, may receive the SI by monitoring the SI-RNTI on a common physical control channel (e.g., PDCCH), decoding a downlink assignment message associated with the SI-RNTI, and receiving the MSIB on a shared channel (e.g., PDSCH). Alternatively, when an RNTI (e.g., a C-RNTI or a Z-RNTI) is assigned for UE 115-e, UE 115-e may monitor the RNTI on a common physical control channel (e.g., a PDCCH), decode a downlink assignment message associated with the RNTI, and receive SI on a shared channel (e.g., a PDSCH) according to information included in the downlink assignment message. In another alternative, UE 115-e may monitor the SI-RNTI to receive broadcast SI, but the UE may also use an RNTI (e.g., a C-RNTI or a zonal RNTI) dedicated to the UE to receive unicast SI.

[0118] In each of the examples described above with respect to UE 115-d, UE 115-e in Figures 7 and 8, the terms broadcast operation and broad beam operation may be used interchangeably at the level at which the operation of UE 115-d, 115-e is described. Similarly, the terms unicast operation and narrow beam operation may be used interchangeably at the level at which the operation of UE 115-d, 115-e is described. In general, when UE 115-d, 115-e is operating in a massive MIMO network, UE 115-d, 115-e may receive periodic synchronization signals 310, 325, 340, 355 as part of broad beam operation and may receive SI as part of either broad beam operation or narrow beam operation. On the other hand, if the UE 115-d, 115-e is operating in a non-massive MIMO network, the UE 115-d, 115-e may receive periodic synchronization signals 310, 325, 340, 355 as part of broadcast operation and may receive SI as part of either broadcast or unicast operation.

[0119] FIG. 9 shows a block diagram 900 of a UE 115-f for use in wireless communication in accordance with various aspects of the present disclosure. The UE 115-f may be an example of one or more aspects of the UE 115 described with respect to FIGS. 1-8. The UE 115-f may be or include a processor. The UE 115-f may include a UE receiver module 710-b, an SI acquisition module 720-b, or a UE transmitter module 730-b, which may be examples of corresponding modules of the UE 115-d (of FIG. 7). The SI acquisition module 720-b may include a service-specific SI acquisition mode module 905, a UE service-specific SI request module 910, or an SI receive module 745-b. The SI receive module 745-b may be an example of the SI receive module 745 of FIG. 7 or FIG. 8. Each of these modules may be in communication with each other.

[0120] The modules of the UE 115-f may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) that can be programmed in any manner known in the art may be used. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0121] In some examples, the UE receiver module 710-b may include at least one RF receiver. The UE receiver module 710-b or RF receiver may be used to receive various types of data or control signals (i.e., transmissions) over one or more communication links of a wireless communication system, such as one or more communication links of the wireless communication system 100 described with reference to FIG. 1. As an example, the UE receiver module 710-b may be used to receive service-specific periodic synchronization signals, as described with reference to FIG. 3B. The UE receiver module 710-b may also be used to receive various signals including one or more forms of SI, as also described with reference to FIG. 3B. As described in more detail below, reception and processing of service-specific synchronization signals and SI signals (e.g., the service-specific periodic synchronization signals 370, 385 of FIG. 3B and the service-specific SIBs 375, 390 (of FIG. 3B)) may additionally be supported through the SI acquisition module 720-b.

[0122] In some examples, the UE transmitter module 730-b may include at least one RF transmitter. The UE transmitter module 730-b or RF transmitter may be used to transmit various types of data or control signals (i.e., transmissions) over one or more communication links of a wireless communication system, such as one or more communication links of the wireless communication system 100 described with respect to FIG. 1. By way of example, as described with respect to FIG. 3B, the UE transmitter module 730-b may be used to transmit SIB Tx requests 372, 388. Transmission of the SIB Tx requests 372, 388 may additionally be assisted, for example, through the SI acquisition module 720-b, as described in more detail below.

[0123] The SI acquisition module 720-b may be used to manage one or more aspects of wireless communications for the UE 115-f. Specifically, in the UE 115-f, the SI acquisition module 720-b may be used to assist in acquiring service-specific SI from the base station 105 in accordance with certain aspects of the embodiments described above. The SI acquisition module 720-b may include a service-specific SI acquisition mode module 905, a UE service-specific SI request module 910, or an SI receiving module 745-b.

[0124] The service-specific SI acquisition mode module 905 may be used by the UE 115-f to assist the UE 115-f in receiving service-specific periodic synchronization signals 370, 385, for example, as shown in FIG. 3B . The received service-specific periodic synchronization signals 370, 385 may indicate to the UE 115-f that service-specific SI is available for the UE 115-f. The service-specific periodic synchronization signals 370, 385 may also indicate whether the UE 115-f should transmit one or more request signals, such as SIB Tx requests 372, 388, for example, to receive service-specific SIBs 375, 390. For example, the UE 115-f may receive a service-specific periodic synchronization signal 370 that indicates to the UE 115-f that service-specific SI is available. The service-specific periodic synchronization signal 370 may indicate that the service-specific SI should be broadcast using specific resources at a specific time. In that case, the service-specific SI acquisition mode module 905 may determine that the UE 115-f must listen to the service-specific SI at a specified time to acquire the service-specific SI. Alternatively, the service-specific periodic synchronization signal 370 may indicate that the service-specific SI should be requested according to a schedule. In this case, the service-specific SI acquisition mode module 905 may determine that the UE 115-f must send one or more requests for the service-specific SI according to the schedule specified by the service-specific periodic synchronization signal 370 to acquire the service-specific SI. In yet another embodiment, the service-specific periodic synchronization signal 385 may indicate that the service-specific SI is available upon request, but that the UE 115-f must explicitly request the service-specific SI. In this case, the service-specific SI acquisition mode module 905 may determine that the UE 115-f must identify which service's SI the UE 115-f needs and then include that identification information in the request.

[0125] When the UE 115-f is operating in a network using an on-demand service-specific SI mode, which means the UE 115-f should send a request to receive service-specific SI, the UE service-specific SI request module 910 may be used to assist in creating such a request. As an example, the UE service-specific SI request module 910 may be used to assemble any one of the SIB Tx requests 372, 388 of FIG. 3B. The UE service-specific SI request module 910 may use information included with the service-specific periodic synchronization signals 370, 385 to determine how to assemble the SIB Tx requests 372, 388. For example, the service-specific periodic synchronization signals 370, 385 may include information indicating where the SIB Tx requests 372, 388 should be transmitted, as well as the timing of such signals.

[0126] The SI receiving module 745-b may be used to assist in receiving service-specific SI transmitted to the UE 115-f. The service-specific SI may be transmitted as a broadcast without requiring a request transmitted by the UE 115-f. In this example, the service-specific SI acquisition mode module 905 may indicate to the SI receiving module 745-b that the service-specific SI should be received via broadcast. The SI receiving module 745-b may then use information included with the service-specific periodic synchronization signal 370, such as a predetermined channel or timing of the broadcast of the service-specific SI, to assist in receiving the service-specific SI. In another example, the service-specific SI may be transmitted as either a broadcast or a unicast in response to a request transmitted by the UE 115-f. In these examples, the service-specific SI acquisition mode module 905 may indicate to the SI receiving module 745-b that the service-specific SI should be received as either a broadcast or a unicast in response to the request. The SI receiving module 745-b may then use information contained with the service-specific periodic synchronization signals 370, 385, such as the predetermined channel or timing of the broadcast or unicast of the SI, to assist in receiving the service-specific SI.

[0127] FIG. 10 shows a block diagram 1000 of a UE 115-g for use in wireless communications, in accordance with various examples. The UE 115-g may be an example of one or more aspects of the UE 115 described with respect to FIGS. 1-9. The UE 115-g may include a UE receiver module 710-c, an SI acquisition module 720-c, and / or a UE transmitter module 730-c, which may be examples of corresponding modules of the UE 115-f (of FIG. 9). The UE 115-g may also include a processor (not shown). Each of these components may be in communication with one another. The SI acquisition module 720-c may include a service-specific SI acquisition mode module 905-a, a UE service-specific SI request module 910-a, and / or an SI receiving module 745-c. The service-specific SI acquisition mode module 905-a may further include a synchronization signal receiving module 1005 and / or a service-specific SI acquisition mode determination module 1010. UE receiver module 710-c and UE transmitter module 730-c may perform the functions of UE receiver module 710 and UE transmitter module 730, respectively, of FIG.

[0128] The modules of the UE 115-g may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) that can be programmed in any manner known in the art may be used. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0129] The service-specific SI acquisition mode module 905-a may include a synchronization signal reception module 1005 and / or a service-specific SI acquisition mode determination module 1010. The synchronization signal reception module 1005 may be used by the UE 115-g to assist the UE 115-g in receiving service-specific periodic synchronization signals 370, 385, for example, as shown in FIG. 3B . The received service-specific periodic synchronization signals 370, 385 may indicate to the UE 115-g whether service-specific SI is available to the UE 115-g and whether the UE 115-g should transmit a request signal, such as a SIB Tx request 372, 388, to receive transmissions of the service-specific SI. Thus, the service-specific SI acquisition mode determination module 1010 may be used to determine from the received service-specific periodic synchronization signals 370, 385 whether the service-specific SI may be received as one or more broadcasts, explicitly requested, or requested according to a schedule. For example, the UE 115-g may receive a service-specific periodic synchronization signal 370 indicating to the UE 115-g that service-specific SI should be broadcast using specific resources at a specific time. In that case, the service-specific SI acquisition mode determination module 1010 may determine that the UE 115-g must listen to the service-specific SI at a specified time to acquire the service-specific SI. Alternatively, the service-specific periodic synchronization signal 370 may indicate that the service-specific SI should be requested according to a schedule. In this case, the service-specific SI acquisition determination mode module 1010 may determine that, to acquire the service-specific SI, the UE 115-g must send one or more requests for the service-specific SI according to the schedule specified by the service-specific periodic synchronization signal 370. In yet another embodiment, the service-specific periodic synchronization signal 385 may indicate that the service-specific SI is available by request, but that the UE 115-g must explicitly request the service-specific SI.In this case, the service-specific SI acquisition mode determination module 1010 may determine that the UE 115-g must identify which service's SI the UE 115-g requires and then include that identification information in the request.

[0130] When the UE 115-g is operating in a network using an on-demand service-specific SI mode, the UE service-specific SI request module 910-a may be used to assist in creating such requests. By way of example, the UE service-specific SI request module 910-a may be used to assemble any one of the SIB Tx requests 372, 388 of FIG. 3B . The UE service-specific SI request module 910-a may use information included with the service-specific periodic synchronization signals 370, 385 to determine how to assemble the SIB Tx requests 372, 388. For example, the service-specific periodic synchronization signals 370, 385 may include information indicating where the SIB Tx requests 372, 388 should be transmitted, as well as the timing of such signals.

[0131] The SI receiving module 745-c may be used to assist in receiving service-specific SI transmitted to the UE 115-g. The service-specific SI may be transmitted as a broadcast without requiring a request transmitted by the UE 115-g. In this example, the service-specific SI acquisition mode determination module 1010 may indicate to the SI receiving module 745-c that the service-specific SI should be received via broadcast. The SI receiving module 745-c may then use information included with the service-specific periodic synchronization signal 370, such as a predetermined channel or timing of the broadcast of the service-specific SI, to assist in receiving the service-specific SI. In another example, the service-specific SI may be transmitted as either a broadcast or a unicast in response to a request transmitted by the UE 115-g. In these examples, the service-specific SI acquisition mode determination module 1010 may indicate to the SI receiving module 745-c that the service-specific SI should be received as either a broadcast or a unicast in response to the request. The SI receiving module 745-c may then use information included with the service-specific periodic synchronization signals 370, 385, such as the predetermined channel or timing of the broadcast or unicast of the SI, to assist in receiving the service-specific SI.

[0132] FIG. 11 shows a block diagram 1100 of a UE 115-h for use in wireless communication in accordance with various aspects of the present disclosure. The UE 115-h may be an example of one or more aspects of the UE 115 described with respect to FIGS. 1-10. The UE 115-h may include a UE receiver module 710-d, an SI acquisition module 720-d, and / or a UE transmitter module 730-d, which may be examples of corresponding modules of the UE 115-d (of FIG. 7). The UE 115-h may also include a processor (not shown). Each of these components may be in communication with one another. The SI acquisition module 720-d may include a master SI acquisition module 1105, an SI processing module 1110, a UE SI request module 1115, and / or other SI acquisition modules 1120. The UE receiver module 710-d and the UE transmitter module 730-d may perform the functions of the UE receiver module 710 and the UE transmitter module 730 of FIG. 7, respectively. In addition, the UE receiver module 710-d may be used to receive SI signals such as OSIB 440, 445, 640, or 645 in FIGS. 4 and 6, and the UE transmitter module 730-d may be used to transmit SI signals such as MSIB transmission request signals 332, 345, 360, 415, or 615 in FIGS. 3A, 4, and 6, or OSIB transmission request 430 or 630 in FIGS. 4 and 6.

[0133] The modules of the UE 115-e may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0134] The master SI acquisition module 1105 may be used to receive a first set of system information (eg, master system information such as the master system information included in the MSIB received at 420 in FIG. 4).

[0135] The SI processing module 1110 may be used to determine, based at least in part on the first set of system information, that additional system information (e.g., non-master system information such as other system information described in relation to FIG. 4) is available.

[0136] The UE SI request module 1115 may be used to send a request for additional system information (e.g., the OSIB transmission request sent at 430 in FIG. 4). In some examples, the UE SI request module 1115 may send multiple requests for additional system information. In some examples, a single OSIB transmission request may indicate one or more elements of additional system information that the UE 115-h wants to receive (e.g., a binary value in the OSIB transmission request may be set to true for each element of additional system information that the UE 115-h wants to receive). In other examples, the UE 115-h may request some type of additional system information in different OSIB transmission requests, and the UE SI request module 1115 may be used to send multiple OSIB transmission requests.

[0137] The other SI acquisition module 1120 may be used to receive additional system information (eg, to receive other system information included in the OSIB received at 440 or 445 in FIG. 4).

[0138] In some embodiments, receiving the first set of system information using the master SI acquisition module 1105 may include receiving an indication of one or more sets of additional system information that are available. In some embodiments, sending the request for the additional system information using the SI request module 1115 may include specifying the one or more sets of additional system information in the request for the additional system information. In some embodiments, the one or more sets of additional system information specified in the request for the additional system information may include the one or more sets of additional system information indicated in the first set of system information.

[0139] In some embodiments, receiving additional system information using the other SI acquisition module 1120 may include at least one of receiving system information indicating which RATs are available in a certain area and how the UE 115-h should select an available RAT (e.g., UE mobility rules and policies), receiving system information indicating which services are available in a certain area and how the UE 115-h should acquire the available services, receiving system information regarding MBMS or PWS services, receiving system information regarding location, positioning, or navigation services, or receiving system information based at least in part on the determined location of the UE 115-h.

[0140] In some embodiments, transmitting the request for the additional system information using the UE SI request module 1115 may include including one or more capabilities of the UE in the request. In these embodiments, receiving the additional system information using the other SI acquisition module 1120 may include receiving the system information based at least in part on the one or more capabilities of the UE 115-h included in the request.

[0141] In some embodiments, sending the request for the additional system information using the UE SI request module 1115 may include including the location of the UE 115-h in the request. In these embodiments, receiving the additional system information using the other SI acquisition module 1120 may include receiving the system information based at least in part on the location of the UE 115-h included in the request.

[0142] In some embodiments, sending the request for the additional system information using the UE SI request module 1115 may include including an identification of the UE 115-h in the request. In these embodiments, receiving the additional system information using the other SI acquisition module 1120 may include receiving the system information based at least in part on the identification of the UE 115-h included in the request.

[0143] FIG. 12 shows a block diagram 1200 of a UE 115-i for use in wireless communication in accordance with various aspects of the present disclosure. The UE 115-i may be an example of one or more aspects of the UE 115 described with respect to FIGS. 1-11. The UE 115-i may include a UE receiver module 710-e, an SI acquisition module 720-e, and / or a UE transmitter module 730-e, which may be examples of corresponding modules of the UE 115-d, 115-f, or 115-h (of FIGS. 7, 9, or 11). The UE 115-i may also include a processor (not shown). Each of these components may be in communication with one another. The SI acquisition module 720-e may include a synchronization signal processing module 1205, a master SI acquisition module 1105-a, an SI processing module 1110-a, a UE SI request module 1115-a, or another SI acquisition module 1120-a. UE receiver module 710-e and UE transmitter module 730-e may perform the functions of UE receiver module 710 and UE transmitter module 730 of FIG. 7, FIG. 9, or FIG.

[0144] The modules of the UE 115-i may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) that can be programmed in any manner known in the art may be used. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0145] The synchronization signal processing module 1205 may be used to decode information received from a downlink channel. The decoded information may indicate that master system information (e.g., an MSIB) is received in response to a master system information request (e.g., an MSIB transmission request, such as the MSIB transmission request transmitted at 415 in FIG. 4). In some examples, the downlink channel may include a synchronization signal (e.g., an instance of the periodic synchronization signal received at 405 in FIG. 4). The decoded information may include information decoded from the synchronization signal.

[0146] The UE SI request module 1115-a may be used to send a master system information request according to information decoded from the downlink channel by the synchronization signal processing module 1205.

[0147] The master SI acquisition module 1105-a may be used to receive master system information (e.g., the master system information included in the MSIB received at 420 in FIG. 4). The master system information may include system information that enables the UE 115-i to perform initial access of the network using one or more of an identification of the network, an identification of a base station in the network, a cell selection configuration and access constraints, or a network access configuration.

[0148] The SI processing module 1110-a may be used to determine, based at least in part on the master system information, that additional system information (e.g., non-master system information such as other system information described with respect to FIG. 4) is available.

[0149] The UE SI request module 1115-a may also be used to send requests for additional system information (e.g., the OSIB transmission request sent at 430 in FIG. 4). In some examples, the UE SI request module 1115-a may send multiple requests for additional system information. In some examples, a single OSIB transmission request may indicate one or more elements of additional system information that the UE 115-i would like to receive (e.g., a binary value in the OSIB transmission request may be set to true for each element of additional system information that the UE 115-i would like to receive). In other examples, the UE 115-i may request some type of additional system information in different OSIB transmission requests, and the UE SI request module 1115-a may be used to send multiple OSIB transmission requests.

[0150] Other SI acquisition modules 1120-a may be used to receive additional system information (eg, to receive other system information included in the OSIB received at 440 or 445 in FIG. 4).

[0151] In some embodiments, receiving the master system information using the master SI acquisition module 1105-a may include receiving an indication of one or more sets of additional system information that are available. In some embodiments, sending a request for the additional system information using the UE SI request module 1115-a may include specifying the one or more sets of additional system information in the request for the additional system information. In some embodiments, the one or more sets of additional system information specified in the request for the additional system information may include the one or more sets of additional system information indicated in the master system information.

[0152] FIG. 13 shows a block diagram 1300 of a UE 115-j for use in wireless communication in accordance with various aspects of the present disclosure. The UE 115-j may be an example of one or more aspects of the UE 115 described with respect to FIGS. 1-12. The UE 115-j may include a UE receiver module 710-f, an SI acquisition module 720-f, or a UE transmitter module 730-f, which may be examples of corresponding modules of the UE 115-d (of FIG. 7). The UE 115-j may also include a processor (not shown). Each of these components may be in communication with one another. The SI acquisition module 720-f may include a signal processing module 1305 or a UE SI request module 1310. The UE receiver module 710-f and the UE transmitter module 730-f may perform the functions of the UE receiver module 710 and the UE transmitter module 730, respectively, of FIG. 7. In addition, the UE receiver module 710-f may be used to receive SI signals, value tags associated with SI, or zone identifiers, such as OSIBs 440, 445, 640, or 645 in FIGS. 4 and 6, and the UE transmitter module 730-f may be used to transmit SI signals, such as MSIB transmission request signals 332, 345, 360, 415, or 615 in FIGS. 3A, 4, and 6, or OSIB transmission requests 430 or 630 in FIGS. 4 and 6.

[0153] The modules of the UE 115-j may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) that can be programmed in any manner known in the art may be used. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0154] The signal processing module 1305 may be used to receive a first signal (e.g., a synchronization signal or paging message, such as an instance of the periodic synchronization signal or paging message received at 605 of FIG. 6, or the MSIB received at 620 of FIG. 6). In some cases, the signal processing module 1305 may receive the first signal while the UE 115-j is communicating with the network using the first system information. The signal processing module 1305 may also be used to determine to request updated system information based at least in part on the first signal.

[0155] The UE SI request module 1310 may be used to request updated system information (e.g., to send the MSIB transmission request sent at 615 of FIG. 6 or the OSIB transmission request sent at 630 of FIG. 6) based at least in part on a determination made by the signal processing module 1305.

[0156] In some embodiments, determining to request updated system information using the signal processing module 1305 may include at least one of determining that the UE 115-j has moved to a zone using second system information that is different from the first system information, determining that the network has changed at least a portion of the first system information, or determining that the UE 115-j has moved more than a predetermined distance from a location where it previously obtained the first system information (e.g., from a location where the UE last obtained the first system information).

[0157] In some embodiments, receiving the first signal using the signal processing module 1305 may include receiving a zone identifier (e.g., an area code, BSIC, or another cell identifier). In some cases, the zone identifier may be received as part of a synchronization signal. In some cases, the zone identifier may be transmitted as part of the synchronization signal. In some cases, the zone identifier may identify one of the neighboring RATs of zones 510, 515, or 520 described with respect to FIG. 5. In these embodiments, the signal processing module 1305 may use the zone identifier to identify that the UE 115-j has moved from the first zone to the second zone. In some embodiments, determining to request updated system information using the signal processing module 1305 may include determining a distance between the current location of the UE 115-j and a location from which the UE 115-j previously (e.g., last time) obtained the first system information, and determining that the determined distance exceeds a predetermined threshold. In some cases, the predetermined threshold may be received from the network. In some cases, a location signal identifying the location of the UE 115-j may also be received. The location signal may be received, for example, as part of receiving the first signal. The location signal may also be received in other manners, such as via a Global Navigation Satellite System (GNSS, e.g., GPS, Galileo, GLONASS, or Beidou).

[0158] FIG. 14 shows a block diagram 1400 of a UE 115-k for use in wireless communication in accordance with various aspects of the present disclosure. The UE 115-k may be an example of one or more aspects of the UE 115 described with respect to FIGS. 1-13. The UE 115-k may include a UE receiver module 710-g, an SI acquisition module 720-g, or a UE transmitter module 730-g, which may be examples of corresponding modules of the UE 115-d or 115-j (of FIGS. 7, 9, or 11). The UE 115-k may also be or include a processor (not shown). Each of these components may be in communication with each other. The SI acquisition module 720-g may include a signal processing module 1305-a or a UE SI request module 1310-a. UE receiver module 710-g and UE transmitter module 730-g may perform the functions of UE receiver module 710 and UE transmitter module 730 of FIG. 7, FIG. 9, or FIG.

[0159] The modules of the UE 115-k may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) that can be programmed in any manner known in the art may be used. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0160] The signal processing module 1305-a may be used to receive a first signal (e.g., a synchronization signal or a paging message, such as an instance of the periodic synchronization signal or paging message received at 605 of FIG. 6, or an MSIB received at 620 of FIG. 6). In some cases, the signal processing module 1305-a may receive the first signal while the UE 115-k is communicating with the network using the first system information, and the first signal may include an indication that at least a portion of the first system information has changed.

[0161] The signal processing module 1305-a may include a modification flag or value tag processing module 1405. The modification flag or value tag processing module 1405 may, in some examples, be used to receive one or more modification flags, each indicating via a counter value or a Boolean variable (e.g., a binary value) that the corresponding portion of the first system information has changed. In some examples, the corresponding portion of the first system information may include a portion of master system information, such as an MSIB or an element of the MSIB. In other examples, the corresponding portion of the first system information may include additional non-master system information, such as an OSIB or an element of the OSIB. The master system information may include one or more of identification information of the network, identification information of base stations in the network, cell selection configuration and access restrictions, or network access configuration information. The master system information may additionally or alternatively include one or more other elements of the master system information described with respect to FIG. 3A, for example. The additional non-master system information may include one or more elements of other system information described with respect to FIG. 4 or FIG. 6. In some embodiments, the modification flag may be received along with (or as part of) the first signal.

[0162] The modification flag or value tag processing module 1405 may also, in some examples, be used to receive one or more value tags corresponding to at least a portion (or various portions) of the changed first system information. In some examples, the one or more value tags may correspond to one or more portions of the master system information (e.g., one or more MSIBs, or one or more elements of one or more MSIBs), one or more portions of additional non-master system information (e.g., one or more OSIBs, or one or more elements of one or more OSIBs), or a combination thereof. The master system information may include one or more of: identification information of the network, identification information of base stations in the network, cell selection configuration and access restrictions, or network access configuration information. The master system information may additionally or alternatively include one or more other elements of the master system information described, for example, with respect to FIG. 3A. The additional non-master system information may include one or more elements of other system information described with respect to FIG. 4 or FIG. 6. In some embodiments, the one or more value tags may be received along with (or as part of) the first signal.

[0163] The signal processing module 1305-a or the modification flag or value tag processing module 1405 may also be used to determine to request updated system information based at least in part on the first signal, a modification flag included in the first signal, or one or more value tags included in the first signal. In some cases, determining to request updated system information may include determining that a received modification flag is set to true. In some cases, determining to request updated system information may include comparing a received value tag with a previously received value tag and determining to request updated system information based at least in part on the comparison (e.g., determining to request updated system information when the value tags do not match).

[0164] The UE SI request module 1310-a may be used to request updated system information based at least in part on a decision made by the signal processing module 1305-a (e.g., to send an MSIB transmission request at 615 of FIG. 6 or to send an OSIB transmission request at 630 of FIG. 6).

[0165] FIG. 15 shows a block diagram 1500 of a UE 115-l for use in wireless communications in accordance with various aspects of the present disclosure. The UE 115-l may have various configurations and may be included in or be part of a personal computer (e.g., a laptop computer, a netbook computer, a tablet computer, etc.), a mobile phone, a smartphone, a PDA, a wireless modem, a USB dongle, a wireless router, a digital video recorder (DVR), an Internet appliance, a game console, an e-reader, etc. The UE 115-l, in some examples, may have an internal power source (not shown), such as a small battery, to facilitate mobile operation. In some examples, the UE 115-l may be an example of one or more aspects of the UE 115 described with reference to FIGS. 1-14. The UE 115-l may be configured to implement at least some of the features and functionality of the UE described with reference to FIGS. 1-14.

[0166] The UE 115-l may include a UE processor module 1510, a UE memory module 1520, at least one UE transceiver module (represented by a UE transceiver module 1530), at least one UE antenna (represented by a UE antenna 1540), or an SI acquisition module 720-h. Each of these components may be in communication with each other directly or indirectly through one or more buses 1535.

[0167] The UE memory module 1520 may include random access memory (RAM) or read-only memory (ROM). The UE memory module 1520 may store computer-readable computer-executable code 1525 including instructions that, when executed, are configured to cause the UE processor module 1510 to perform various functions described herein with respect to wireless communications, including, for example, transmitting pilot signals. Alternatively, the code 1525 may not be directly executable by the UE processor module 1510, but may be configured (e.g., when compiled and executed) to cause the UE 115-l to perform various functions described herein.

[0168] The UE processor module 1510 may include an intelligent hardware device such as a central processing unit (CPU), a microcontroller, an ASIC, etc. The UE processor module 1510 may process information received through the UE transceiver module 1530 or information to be sent to the UE transceiver module 1530 for transmission through the UE antenna 1540. The UE processor module 1510 may handle various aspects of communicating over (or managing communications over) the wireless medium.

[0169] The UE transceiver module 1530 may include a modem configured to modulate packets, provide the modulated packets to the UE antenna 1540 for transmission, and demodulate packets received from the UE antenna 1540. The UE transceiver module 1530, in some examples, may be implemented as one or more UE transmitter modules and one or more separate UE receiver modules. The UE transceiver module 1530 may support communication over one or more wireless channels. The UE transceiver module 1530 may be configured to communicate bidirectionally with one or more base stations via the UE antenna 1540, such as one or more of the base stations 105 described with respect to FIG. 1, FIG. 2, FIG. 4, or FIG. 6. Although the UE 115-l may include a single UE antenna, there may be instances where the UE 115-l may include multiple UE antennas 1540.

[0170] The UE state module 1550 may be used, for example, to manage the transition of the UE 115-l between multiple RRC connection states and may be in direct or indirect communication with other components of the UE 115-l through one or more buses 1535. The UE state module 1550, or portions thereof, may include a processor, and / or some or all of the functionality of the UE state module 1550 may be performed by or in association with the UE processor module 1510.

[0171] The SI acquisition module 720-h may be configured to perform or control some or all of the system information acquisition features or functions described with respect to Figures 1-14. The SI acquisition module 720-h, or portions thereof, may include a processor, or some or all of the functions of the SI acquisition module 720-h may be performed by or in association with the UE processor module 1510. In some examples, the SI acquisition module 720-h may be an example of the SI acquisition module 720 described with respect to Figures 7-14.

[0172] FIG. 16 shows a block diagram 1600 of a base station 105-e for wireless communication in accordance with various aspects of the present disclosure. The base station 105-e may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6. The base station 105-e may also be or include a processor. The base station 105-e may include a base station (or RRH) receiver module 1610, an SI transmission module 1620, or a base station (or RRH) transmitter module 1630. The SI transmission module 1620 may include an SI transmission mode module 1635, a base station SI request module 1640, or an SI transmission module 1645. Each of these modules may be in communication with one another. In a configuration of the base station 105-e that includes one or more RRHs, one or more aspects of the modules 1610, 1620, or 1630 may be transferred to each of the one or more RRHs.

[0173] The base station 105-e may be configured to perform aspects of the functionality described herein through the base station receiver module 1610, the SI transmission module 1620, and / or the base station transmitter module 1630. For example, as described in more detail herein, the base station 105-e may be configured to determine an SI transmission mode, receive a request for SI (e.g., from a UE 115), and transmit SI according to one or more of the received request and the determined transmission mode.

[0174] The components of the base station 105-e may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functionality of each component may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0175] In some examples, the base station receiver module 1610 may include at least one RF receiver. The base station receiver module 1610 or RF receiver may be used to receive various types of data or control signals (i.e., transmissions) over one or more communication links of a wireless communication system, such as one or more communication links of the wireless communication system 100 described with respect to FIG. 1. By way of example, as described with respect to FIGs. 3A, 3B, and 4, the base station receiver module 1610 may be used to receive MSIB transmission request signals 332, 345, 360. As described in more detail below, reception and processing of SI request signals (e.g., MSIB transmission request signals 332, 345, 360 of FIG. 3A) may additionally be assisted through the SI transmission module 1620.

[0176] In some examples, the base station transmitter module 1630 may include at least one RF transmitter. The base station transmitter module 1630 or RF transmitter may be used to transmit various types of data or control signals (i.e., transmissions) over one or more communication links of a wireless communication system, such as one or more communication links of the wireless communication system 100 described with reference to FIG. 1. By way of example, the base station transmitter module 1630 may be used to transmit periodic synchronization signals 310, 325, 340, or 355, as described with reference to FIGS. 3A, 3B, and 4. The base station transmitter module 1630 may also be used to transmit various signals including one or more forms of SI, such as broadcast MSIBs 315, 330, 342, or unicast MSIBs 358, as also described with reference to FIGS. 3A, 3B, and 4. Transmission of synchronization and SI signals may additionally be supported through the SI transmission module 1620, as described in more detail below.

[0177] The SI transmission module 1620 may be used to manage one or more aspects of wireless communications for the base station 105-e. Specifically, the SI transmission module 1620 may be used to facilitate transmission of SI from the base station 105-e in accordance with certain aspects of the embodiments described above. The SI transmission module 1620 may include an SI transmission mode module 1635, a base station SI request module 1640, or an SI transmission module 1645.

[0178] The SI transmission mode module 1635 may be used by the base station 105-e to assist the base station 105-e in determining the SI transmission mode and in transmitting periodic synchronization signals 310, 325, 340, and 355, for example, as shown in FIGS. 3A and 4. Examples of different transmission modes may be shown and described above with respect to FIG. 3A. For example, one transmission mode may include SI broadcasting with fixed periodic scheduling and targeted to the cell edge, as shown in the transmission / reception timeline 305 of FIG. 3A. In this example, the base station 105-e may transmit a periodic synchronization signal 310 that may indicate to the UE 115 that SI information should be broadcast periodically, without the UE 115 having to send a specific request for SI. This SI transmission mode may be advantageously used when a large number of UEs 115 are requesting SI. Because the SI transmission is broadcast, the number of UEs 115 needing SI does not affect the transmission of the SI. However, this SI transmission mode may also have some drawbacks. That is, broadcasting targeted to the cell edge may require a large amount of transmit power, which may result in wasted radio resources when the number of UEs 115 camped on the cell or zone is small. Additionally, in this transmission mode, the base station 105-e may broadcast SI regardless of the number of UEs 115 camped on the cell or zone. Even when no UEs 115 are camped on the cell or zone, the base station 105-e may continue to broadcast SI, resulting in wasted resources and potential interference.

[0179] Another transmission mode may include SI broadcasting targeted to the cell edge with on-demand periodic scheduling, as shown in the transmission / reception timeline 320 of FIG. 3A. In this example, the base station 105-e may transmit a periodic synchronization signal 325 that may indicate to the UE 115 that SI information should be periodically broadcast in response to the MSIB transmission request signal 332. This SI transmission mode may be advantageously used so that the base station 105-e is not required to perform resource allocation and data scheduling for each UE and only needs to continue the periodic broadcast. Additionally, if the UE 115 has not requested SI, the base station 105-e may suspend its broadcast to save energy and reduce interference. Conversely, targeting the broadcast to the cell edge may still require the use of a large amount of power, which may still result in wasted power and potential interference.

[0180] Yet another transmission mode may include SI broadcasting targeted to a group of UEs 115 with on-demand, aperiodic scheduling, as shown in the transmission / reception timeline 335 of FIG. 3A. In this example, the base station 105-e may transmit a periodic synchronization signal 340 that may indicate to the UEs 115 that SI information should be broadcast aperiodic in response to an MSIB transmission request signal 345. This SI transmission mode may be advantageously used to allow the base station 105-e to stop SI broadcasting when no UEs are requesting SI, thereby saving energy and reducing potential interference. Additionally, because the base station 105-e targets only a group of UEs 115 (instead of the cell edge), less transmit power is required. However, this transmission mode may impose a higher processing load on the base station 105-e, as it may be required to optimize SI transmission for the group of UEs. Additionally, this mode is still not as efficient as unicast transmission, although efficiency may depend on the number of UEs 115 requesting SI.

[0181] A fourth transmission mode may include SI unicast with on-demand, aperiodic scheduling targeted to a single UE 115, as shown in transmission / reception timeline 350 of FIG. 3A. In this example, base station 105-e may transmit a periodic synchronization signal 355 that may indicate to UE 115 that SI information should be unicast aperiodically in response to MSIB transmission request signal 360. This SI transmission mode has the advantage of allowing base station 105-e to stop SI transmission when no UE 115 has requested SI, and may provide greater efficiency in providing SI to UEs 115. However, this mode comes with an increased processing load at base station 105-e.

[0182] The transmission modes described above are generally described using the terms broadcast and unicast, and may be most appropriately used when the network in which the base station 105-e participates is a non-massive MIMO network. On the other hand, when a massive MIMO environment is configured, broad beam and narrow beam transmission may be used instead of broadcast or unicast transmission. Broad beam transmission may provide wide coverage capable of serving more than one UE 115, but broad beam transmission may require additional radio resources compared to narrow beam transmission serving only a single UE 115.

[0183] In general, broad beam or broadcast operation provides higher efficiency in situations where there are a large number of UEs 115 attempting to acquire SI, while narrow beam or unicast operation provides higher efficiency in situations where there are fewer UEs 115 attempting to acquire SI.

[0184] The SI transmission mode module 1635 may assist in transitioning between transmission modes, for example. One implementation may include changing the transmission mode based on the number of UEs 115 requesting SI acquisition, network load, congestion, or available radio resources.

[0185] For example, in a non-massive MIMO situation, if the number of UEs 115 requesting SI acquisition is greater than a predetermined threshold number N, the SI transmission mode module 1635 may determine to include an indicator indicating that the SI is broadcast periodically (e.g., this indicator may indicate that the SI transmission is fixed) in the periodic synchronization signal 310. In this situation, the base station 105-e may periodically broadcast the SI without requiring a specific SI request from the UE 115, and the UE 115 may acquire the SI, for example, by monitoring the SI-RNTI and / or RNTI (e.g., C-RNTI / Z-RNTI) assigned to the UE in question, if any, and as described above.

[0186] However, in a non-massive MIMO situation, if the number of UEs 115 requesting SI acquisition is equal to or less than a predetermined threshold number N or less than a predetermined threshold number N2, the SI transmission mode module 1635 may determine to include an indicator indicating that SI is transmitted in response to a request (e.g., this indicator may indicate that SI transmission is on-demand) in the periodic synchronization signal 325, 340, 355. In this situation, the base station 105-e may transmit SI in response to a specific SI request from the UE 115, and the UE 115 may acquire the SI, for example, by monitoring the SI-RNTI and / or RNTI (e.g., C-RNTI / Z-RNTI) assigned to the UE in question, if any, and as described above. In this situation, the base station 105-e may transmit SI either by broadcasting the SI according to on-demand periodic scheduling targeted to a cell edge, by broadcasting the SI according to on-demand aperiodic scheduling targeted to a group of UEs 115, or by unicasting the SI according to on-demand aperiodic scheduling targeted to a single UE 115.

[0187] In a massive MIMO situation, if the number of UEs 115 requesting SI acquisition is greater than a predetermined threshold number N, the SI transmission mode module 1635 may determine to include an indicator indicating that SI is periodically transmitted via broad beam operation (e.g., this indicator may indicate that SI transmission is fixed) in the periodic synchronization signal 310. In this situation, the base station 105-e may periodically transmit SI via broad beam without requiring a specific SI request from the UE 115, and the UE 115 may acquire the SI, for example, by monitoring the SI-RNTI and / or RNTI (e.g., C-RNTI / Z-RNTI) assigned to the UE in question, if any, and as described above.

[0188] However, in a massive MIMO situation, if the number of UEs 115 requesting SI acquisition is equal to or less than a predetermined threshold number N or less than a predetermined threshold number N2, the SI transmission mode module 1635 may determine to include an indicator in the periodic synchronization signal 325, 340, 355 indicating that SI is transmitted in response to a request (e.g., this indicator may indicate that SI transmission is on-demand). The SI transmission may be either broad beam or narrow beam. In this situation, the base station 105-e may transmit SI in response to a specific SI request from the UE 115, and the UE 115 may acquire the SI, for example, by monitoring the SI-RNTI and / or RNTI (e.g., C-RNTI / Z-RNTI), if any, assigned to the UE in question and as described above. In this situation, the base station 105-e may transmit the SI either by using broad beam transmission of the SI according to on-demand periodic scheduling targeting the cell edge, by using broad beam transmission of the SI according to on-demand irregular scheduling targeting a group of UEs 115, or by using narrow beam transmission of the SI according to on-demand irregular scheduling targeting a single UE 115.

[0189] If the base station 105-e is operating in a network using an on-demand SI mode, which means that the base station 105-e should receive a request from the UE 115 before transmitting SI, the base station SI request module 1640 may be used to assist in receiving such a request. As an example, the base station SI request module 1640 may be used to receive any one of the MSIB transmission request signals 332, 345, 360 of FIG. 3A. The MSIB transmission request signals 332, 345, 360 may be transmitted according to information included with the periodic synchronization signals 325, 340, 355, such as the destination and / or timing to be used for the MSIB transmission request signals 332, 345, 360.

[0190] The SI transmission module 1645 may be used to assist in the transmission of SI to the UE 115. The SI may be transmitted as broadcast or broad beam operation without any need for a request transmitted by the UE 115. In this example, the SI transmission mode module 1635 may indicate to the SI transmission module 1645 that the SI should be transmitted via broadcast or broad beam operation. The SI transmission module 1645 may then assist in the transmission of the SI according to information included with the periodic synchronization signal 310, such as a predetermined channel or timing of the broadcast of the SI. In another example, the SI may be transmitted as either broadcast or unicast (or either broad beam or narrow beam operation) in response to a request transmitted by the UE 115. In these examples, the SI transmission mode module 1635 may indicate to the SI transmission module 1645 that the SI should be transmitted as either broadcast or unicast (or either broad beam or narrow beam operation) in response to the request. The SI transmission module 1645 may then assist in transmitting the SI according to information included with the periodic synchronization signals 325, 340, 355, such as using a predetermined channel or timing for broadcasting or unicasting (or broad beam or narrow beam operation) the SI.

[0191] FIG. 17 shows a block diagram 1700 of a base station 105-f for use in wireless communications, according to various examples. The base station 105-f may be an example of one or more aspects of the base station 105 described with reference to FIGS. 1-6 and 14. The base station 105-f may include a base station (or RRH) receiver module 1610-a, an SI transmission module 1620-a, or a base station (or RRH) transmitter module 1630-a, which may be examples of corresponding modules of the base station 105-e (of FIG. 16). The base station 105-f may also include a processor (not shown). Each of these components may be in communication with one another. The SI transmission module 1620-a may include an SI transmission mode module 1635-a, a base station SI request module 1640-a, or an SI transmission module 1645-a. The SI transmission mode module 1635-a may further include a synchronization signal transmission module 1705 or an SI transmission mode determination module 1710. The base station receiver module 1610-a and the base station transmitter module 1630-a may perform the functions of the base station receiver module 1610 and the base station transmitter module 1630, respectively, of Figure 16. In a configuration of a base station 105-f that includes one or more RRHs, one or more aspects of modules 1610-a, 1620-a, or 1630-a may be transferred to each of the one or more RRHs.

[0192] The modules of the base station 105-f may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0193] The synchronization signal transmission module 1705 of the SI transmission mode module 1635-a may be used by the base station 105-f to transmit a periodic synchronization signal to indicate to the UE 115 whether SI acquisition should be performed via a fixed periodic mode or an on-demand mode. The synchronization signal transmission module 1705 may transmit, for example, the periodic synchronization signals 310, 325, 340, 355 as shown in FIG. 3A.

[0194] The base station 105-f may further operate in a particular SI transmission mode, which may be determined through use of the SI transmission mode determination module 1710. Examples of different transmission modes may be shown and described above with respect to FIG. 3A. For example, one transmission mode may include SI broadcasting with fixed periodic scheduling and targeted to the cell edge, as shown in the transmit / receive timeline 305 of FIG. 3A. In this example, the base station 105-f may transmit a periodic synchronization signal 310, which may indicate to the UE 115 that SI information should be broadcast periodically, without the UE 115 having to send a specific request for SI.

[0195] Another transmission mode may include SI broadcasts that have on-demand periodic scheduling and target the cell edge, as shown in the transmit / receive timeline 320 of FIG. 3A. In this example, base station 105-f may transmit a periodic synchronization signal 325 that may indicate to UE 115 that SI information should be broadcast periodically in response to the MSIB transmission request signal 332.

[0196] Yet another transmission mode may include SI broadcasts that have on-demand aperiodic scheduling and target a group of UEs 115, as shown in the transmit / receive timeline 335 of FIG. 3A. In this example, base station 105-f may transmit a periodic synchronization signal 340 that may indicate to UE 115 that SI information should be broadcast aperiodically in response to the MSIB transmission request signal 345.

[0197] A fourth transmission mode may include SI unicasts that have on-demand aperiodic scheduling and target a single UE 115, as shown in the transmit / receive timeline 350 of FIG. 3A. In this example, base station 105-f may transmit a periodic synchronization signal 355 that may indicate to UE 115 that SI information should be unicast aperiodically in response to the MSIB transmission request signal 360.

[0198] The transmission modes described above are generally described using the terms broadcast and unicast, which may be most appropriately used when the network in which base station 105-f participates is a non-massive MIMO network. On the other hand, when a massive MIMO environment is configured, broadbeam and narrowbeam transmissions may be used instead of broadcast or unicast transmissions. Broadbeam transmissions may provide wide coverage that can serve two or more UEs 115, but broadbeam transmissions may require additional radio resources compared to narrowbeam transmissions that serve only a single UE 115.

[0199] In general, broad beam or broadcast operation provides higher efficiency in situations where there are a large number of UEs 115 attempting to acquire SI, while narrow beam or unicast operation provides higher efficiency in situations where there are fewer UEs 115 attempting to acquire SI.

[0200] The SI transmission mode determination module 1710 may assist in transitioning between transmission modes, for example. One implementation may include changing the transmission mode based on the number of UEs 115 requesting SI acquisition, network load, congestion, or available radio resources.

[0201] For example, in a non-massive MIMO situation, if the number of UEs 115 requesting SI acquisition is greater than a predetermined threshold number N, the SI transmission mode determination module 1710 may determine to include an indicator indicating that the SI is broadcast periodically (e.g., this indicator may indicate that the SI transmission is fixed) in the periodic synchronization signal 310. In this situation, the base station 105-f may periodically broadcast the SI without requiring a specific SI request from the UE 115, and the UE 115 may acquire the SI, for example, by monitoring the SI-RNTI and / or RNTI (e.g., C-RNTI / Z-RNTI) assigned to the UE in question, if any, and as described above.

[0202] However, in a non-massive MIMO situation, if the number of UEs 115 requesting SI acquisition is equal to or less than a predetermined threshold number N or is less than a predetermined threshold number N2, the SI transmission mode determination module 1710 may determine to include an indicator indicating that SI is transmitted in response to a request (e.g., this indicator may indicate that SI transmission is on-demand) in the periodic synchronization signal 325, 340, 355. In this situation, the base station 105-f may transmit SI in response to a specific SI request from the UE 115, and the UE 115 may acquire the SI, for example, by monitoring the SI-RNTI and / or RNTI (e.g., C-RNTI / Z-RNTI) assigned to the UE in question, if any, and as described above. In this situation, the base station 105-f may transmit the SI by either broadcasting the SI according to on-demand periodic scheduling targeted at the cell edge, broadcasting the SI according to on-demand irregular scheduling targeted at a group of UEs 115, or unicasting the SI according to on-demand irregular scheduling targeted at a single UE 115.

[0203] In a massive MIMO situation, if the number of UEs 115 requesting SI acquisition is greater than a predetermined threshold number N, the SI transmission mode determination module 1710 may determine to include an indicator indicating that SI is periodically transmitted via broad beam operation (e.g., this indicator may indicate that SI transmission is fixed) in the periodic synchronization signal 310. In this situation, the base station 105-f may periodically transmit SI via broad beam without requiring a specific SI request from the UE 115, and the UE 115 may acquire the SI, for example, by monitoring the SI-RNTI and / or RNTI (e.g., C-RNTI / Z-RNTI) assigned to the UE in question, if any, and as described above.

[0204] However, in a massive MIMO situation, if the number of UEs 115 requesting SI acquisition is equal to or less than a predetermined threshold number N or less than a predetermined threshold number N2, the SI transmission mode determination module 1710 may determine to include an indicator in the periodic synchronization signal 325, 340, 355 indicating that SI is transmitted in response to a request (e.g., this indicator may indicate that SI transmission is on-demand). The SI transmission may be either broad beam or narrow beam. In this situation, the base station 105-f may transmit SI in response to a specific SI request from the UE 115, and the UE 115 may acquire the SI, for example, by monitoring the SI-RNTI and / or RNTI (e.g., C-RNTI / Z-RNTI), if any, assigned to the UE in question and as described above. In this situation, the base station 105-f may transmit the SI either by using broad beam transmission of the SI according to on-demand periodic scheduling targeting the cell edge, by using broad beam transmission of the SI according to on-demand irregular scheduling targeting a group of UEs 115, or by using narrow beam transmission of the SI according to on-demand irregular scheduling targeting a single UE 115.

[0205] If the base station 105-f is operating in a network using an on-demand SI mode, which means that the base station 105-f should receive a request from the UE 115 before transmitting SI, the base station SI request module 1640-a may be used to assist in receiving such a request. As an example, the base station SI request module 1640-a may be used to receive any one of the MSIB transmission request signals 332, 345, 360 of FIG. 3A. The MSIB transmission request signals 332, 345, 360 may be transmitted according to information included with the periodic synchronization signals 325, 340, 355, such as the destination and / or timing to be used for the MSIB transmission request signals 332, 345, 360.

[0206] The SI transmission module 1645-a may be used to assist in the transmission of SI to the UE 115. The SI may be transmitted as broadcast or broad beam operation without any need for a request transmitted by the UE 115. In this example, the SI transmission mode module 1635-a may indicate to the SI transmission module 1645-a that the SI should be transmitted via broadcast or broad beam operation. The SI transmission module 1645-a may then assist in the transmission of the SI according to information included with the periodic synchronization signal 310, such as a predetermined channel or timing of the broadcast of the SI. In another example, the SI may be transmitted as either broadcast or unicast (or either broad beam operation or narrow beam operation) in response to a request transmitted by the UE 115. In these examples, the SI transmission mode module 1635-a may indicate to the SI transmission module 1645-a that the SI should be transmitted as either broadcast or unicast (or either broad beam operation or narrow beam operation) in response to the request. The SI transmission module 1645-a may then assist in transmitting the SI according to information included with the periodic synchronization signals 325, 340, 355, such as using a predetermined channel or timing for broadcasting or unicasting (or broad beam or narrow beam operation) the SI.

[0207] FIG. 18 shows a block diagram 1800 of a base station 105-g for use in wireless communications in accordance with various aspects of the present disclosure. The base station 105-g may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6, 16, and 17. The base station 105-g may include a base station (or RRH) receiver module 1610-b, an SI transmission module 1620-b, or a base station (or RRH) transmitter module 1630-b, which may be examples of corresponding modules of the base station 105-e (of FIG. 16). The base station 105-g may also include a processor (not shown). Each of these components may be in communication with one another. The SI transmission module 1620-b may include a service-specific SI transmission mode module 1805, a base station service-specific SI request module 1810, or an SI transmission module 1645-b. The base station receiver module 1610-b and the base station transmitter module 1630-b may perform the functions of the base station receiver module 1610 and the base station transmitter module 1630, respectively, of Figure 16. Additionally, the base station receiver module 1610-b may be used to receive SI signals, such as the SIB Tx requests 372, 388 of Figure 3B, and the base station transmitter module 1630-b may be used to transmit the service-specific SIBs 375, 390 of Figure 3B. In a configuration of the base station 105-g that includes one or more RRHs, one or more aspects of the modules 1610-b, 1620-b, or 1630-b may be transferred to each of the one or more RRHs.

[0208] The modules of the base station 105-g may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0209] In some examples, the base station receiver module 1610-b may include at least one RF receiver. The base station receiver module 1610-b or RF receiver may be used to receive various types of data or control signals (i.e., transmissions) over one or more communication links of a wireless communication system, such as one or more communication links of the wireless communication system 100 described with respect to FIG. 1. As an example, the base station receiver module 1610-b may be used to receive requests for service-specific SI, as described with respect to FIG. 3B. As described in more detail below, reception and processing of service-specific SI requests (e.g., SIB Tx requests 372, 388 of FIG. 3B) may additionally be assisted through the SI transmit module 1620-b.

[0210] In some examples, the base station transmitter module 1630-b may include at least one RF transmitter. The base station transmitter module 1630-b or RF transmitter may be used to transmit various types of data or control signals (i.e., transmissions) over one or more communication links of a wireless communication system, such as one or more communication links of the wireless communication system 100 described with reference to FIG. 1. By way of example, as described with reference to FIG. 3B, the base station transmitter module 1630-b may be used to transmit service-specific periodic synchronization signals 370, 385 and service-specific SIBs 375, 390. Transmission of the service-specific periodic synchronization signals 370, 385 and service-specific SIBs 375, 390 may additionally be supported through the SI transmission module 1620-b, for example, as described in more detail below.

[0211] The SI transmission module 1620-b may be used to manage one or more aspects of wireless communications for the base station 105-g. Specifically, in the base station 105-g, the SI transmission module 1620-b may be used to assist in transmitting service-specific SI to the UE 115 in accordance with certain aspects of the embodiments described above. The SI transmission module 1620-b may include a service-specific SI transmission mode module 1805, a base station service-specific SI request module 1810, or an SI transmission module 1645-b.

[0212] The service-specific SI transmission mode module 1805 may be used by the base station 105-g to assist the base station 105-g in transmitting service-specific periodic synchronization signals 370, 385, for example, as shown in FIG. 3B . The transmitted service-specific periodic synchronization signals 370, 385 may indicate to the UE 115 that service-specific SI is available for the UE 115. The service-specific periodic synchronization signals 370, 385 may also indicate whether the UE 115 should transmit one or more request signals, such as SIB Tx requests 372, 388, to receive service-specific SIBs 375, 390. The service-specific periodic synchronization signal 370 may indicate that the service-specific SI should be broadcast using specific resources at specific times. Alternatively, the service-specific periodic synchronization signal 370 may indicate that the service-specific SI should be requested according to a schedule. In yet another embodiment, the service-specific periodic synchronization signal 385 may indicate that the service-specific SI is available by request, but that the UE 115 must explicitly request the service-specific SI.

[0213] If the service-specific SI transmission mode module 1805 indicates in the service-specific periodic synchronization signal 370, 385 that the UE 115 should transmit a request for service-specific SI, the base station service-specific SI request module 1810 may be used by the base station 105-g to receive any such requests. As described in FIG. 3B , the request for service-specific SI may be in the form of a SIB Tx request 372, 388. The SIB Tx request 372 may be received by the base station service-specific SI request module 1810 at a time indicated in a schedule included with the service-specific periodic synchronization signal 370 and may therefore indicate to the base station 105-g that corresponding service-specific SI should be transmitted to the requesting UE 115. Alternatively, the base station 105-g may receive a SIB Tx request 388 that explicitly requests service-specific SI.

[0214] The SI transmission module 1645-b may be used to assist in transmitting service-specific SI to the UE 115. The service-specific SI may be transmitted as a broadcast without any request being transmitted by the UE 115. In this example, the service-specific SI transmission mode module 1805 may indicate to the SI transmission module 1645-b that the service-specific SI should be transmitted via broadcast. The SI transmission module 1645-b may then assist in transmitting the service-specific SI in accordance with the service-specific periodic synchronization signal 370, for example, using a predetermined channel or timing of the broadcast of the service-specific SI. In another example, the service-specific SI may be transmitted as either a broadcast or a unicast in response to a request transmitted by the UE 115. In these examples, the service-specific SI transmission mode module 1805 may indicate to the SI transmission module 1645-b that the service-specific SI should be transmitted as either a broadcast or a unicast in response to the request. The SI transmission module 1645-b may then facilitate transmission of service-specific SI according to information included with the service-specific periodic synchronization signals 370, 385 and according to the received SIB Tx requests 372, 388.

[0215] FIG. 19 shows a block diagram 1900 of a base station 105-h for use in wireless communications in accordance with various aspects of the present disclosure. The base station 105-h may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6 and 16-18. The base station 105-h may include a base station (or RRH) receiver module 1610-c, an SI transmission module 1620-c, or a base station (or RRH) transmitter module 1630-c, which may be examples of corresponding modules of the base station 105-e (of FIG. 16). The base station 105-h may also include a processor (not shown). Each of these components may be in communication with one another. The SI transmission module 1620-c may include a service-specific SI transmission mode module 1805-a, a base station service-specific SI request module 1810-a, or an SI transmission module 1645-c. The service-specific SI transmission mode module 1805-a may further include a synchronization signal transmission module 1905 and / or a service-specific SI transmission mode determination module 1910. The base station receiver module 1610-c and the base station transmitter module 1630-c may perform the functions of the base station receiver module 1610 and the base station transmitter module 1630 of FIG. 16, respectively. In addition, the base station receiver module 1610-c may be used to receive SI signals such as the SIB Tx requests 372, 388 of FIG. 3B, and the base station transmitter module 1630-c may be used to transmit the service-specific SIBs 375, 390 of FIG. 3B. In a configuration of a base station 105-h that includes one or more RRHs, one or more aspects of the modules 1610-c, 1620-c, or 1630-c may be transferred to each of the one or more RRHs.

[0216] The modules of the base station 105-h may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0217] The SI transmission module 1620-c may be used to manage one or more aspects of wireless communications for the base station 105-h. Specifically, at the base station 105-h, the SI transmission module 1620-c may be used to assist in transmitting service-specific SI to the UE 115 in accordance with certain aspects of the embodiments described above.

[0218] The service-specific SI transmission mode module 1805-a may include a synchronization signal transmission module 1905 and / or a service-specific SI transmission mode determination module 1910. The synchronization signal transmission module 1905 may be used by the base station 105-h to assist the base station 105-h in transmitting service-specific periodic synchronization signals 370, 385, for example, as shown in FIG. 3B . The transmitted service-specific periodic synchronization signals 370, 385 may indicate to the UE 115 whether service-specific SI is available to the UE 115 and whether the UE 115 may acquire the service-specific SI through broadcast or through a request. Thus, the service-specific SI transmission mode determination module 1910 may be used to determine how the UE 115 should acquire the service-specific SI, and the service-specific SI transmission mode determination module 1910 may include an indication thereof in the service-specific periodic synchronization signals 370, 385. Thus, the service-specific periodic synchronization signal 370, 385 may indicate whether the UE 115 should transmit one or more request signals, such as SIB Tx requests 372, 388, to receive service-specific SIBs 375, 390. The service-specific periodic synchronization signal 370 may indicate that the service-specific SI should be broadcast using specific resources at specific times. Alternatively, the service-specific periodic synchronization signal 370 may indicate that the service-specific SI should be requested according to a schedule. In yet another embodiment, the service-specific periodic synchronization signal 385 may indicate that the service-specific SI is available by request, but that the UE 115 must explicitly request the service-specific SI.

[0219] If the service-specific SI transmission mode determination module 1910 indicates in the service-specific periodic synchronization signal 370, 385 that the UE 115 should transmit a request for service-specific SI, the base station service-specific SI request module 1810-a may be used by the base station 105-h to receive any such requests. As described in FIG. 3B , the request for service-specific SI may be in the form of a SIB Tx request 372, 388. The SIB Tx request 372 may be received by the base station service-specific SI request module 1810-a at a time indicated in a schedule included with the service-specific periodic synchronization signal 370, and may therefore indicate to the base station 105-h that corresponding service-specific SI should be transmitted to the requesting UE 115. Alternatively, the base station 105-h may receive a SIB Tx request 388 that explicitly requests service-specific SI.

[0220] The SI transmission module 1645-c may be used to assist in transmitting service-specific SI to the UE 115. The service-specific SI may be transmitted as a broadcast without any request being transmitted by the UE 115. In this example, the service-specific SI transmission mode determination module 1910 may indicate to the SI transmission module 1645-c that the service-specific SI should be transmitted via broadcast. The SI transmission module 1645-c may then assist in transmitting the service-specific SI in accordance with the service-specific periodic synchronization signal 370, for example, using a predetermined channel or timing of the broadcast of the service-specific SI. In another example, the service-specific SI may be transmitted as either a broadcast or a unicast in response to a request transmitted by the UE 115. In these examples, the service-specific SI transmission mode determination module 1910 may indicate to the SI transmission module 1645-c that the service-specific SI should be transmitted as either a broadcast or a unicast in response to the request. The SI transmission module 1645-c may then facilitate transmission of service-specific SI according to information included with the service-specific periodic synchronization signals 370, 385 and according to the received SIB Tx requests 372, 388.

[0221] FIG. 20 shows a block diagram 2000 of a base station 105-i for use in wireless communications in accordance with various aspects of the present disclosure. The base station 105-i may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6 and 16-19. The base station 105-i may include a base station (or RRH) receiver module 1610-d, an SI transmission module 1620-d, or a base station (or RRH) transmitter module 1630-d, which may be examples of corresponding modules of the base station 105-e (of FIG. 16). The base station 105-i may also include a processor (not shown). Each of these components may be in communication with one another. The SI transmission module 1620-d may include a master SI transmission management module 2005, an SI request processing module 2010, or another SI transmission management module 2015. The base station receiver module 1610-d and the base station transmitter module 1630-d may perform the functions of the base station receiver module 1610 and the base station transmitter module 1630, respectively, of Figure 16. Additionally, the base station receiver module 1610-d may be used to receive SI signals such as the MSIB request to send signals 332, 345, 360, 415, or 615 of Figures 3A, 4, and 6, or the OSIB request to send signals 430 or 630 of Figures 4 and 6, and the base station transmitter module 1630-d may be used to transmit SI signals such as the OSIB signals 440, 445, 640, or 645 of Figures 4 and 6. In a configuration of the base station 105-i that includes one or more RRHs, one or more aspects of modules 1610-d, 1620-d, or 1630-d may be transferred to each of the one or more RRHs.

[0222] The modules of base station 105-i may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0223] The master SI transmission management module 2005 may be used to transmit a first set of system information (eg, master system information such as the master system information included in the MSIB transmitted at 420 in FIG. 4).

[0224] The SI request processing module 2010 may be used to receive a request (e.g., the OSIB transmission request received at 430 in FIG. 4) for additional system information (e.g., non-master system information such as other information described with respect to FIG. 4).

[0225] The other SI transmission management module 2015 may be used to transmit additional system information based at least in part on the request (e.g., to transmit other system information included in the OSIB transmitted at 440 or 445 of FIG. 4).

[0226] In some embodiments, transmitting the first set of system information using the master SI transmission management module 2005 may include transmitting an indication of one or more sets of additional system information that are available. In some embodiments, receiving a request for additional system information using the SI request processing module 2010 may include receiving one or more requests for additional system information corresponding to multiple sets of additional system information to be transmitted. For example, the SI request processing module 2010 may receive a single OSIB transmission request indicating one or more elements of additional system information that the UE wants to receive (e.g., a binary value in the OSIB transmission request may be set to true for each element of additional system information that the UE wants to receive). In other examples, the UE may request some type of additional system information in different OSIB transmission requests, and the SI request processing module 2010 may receive multiple OSIB transmission requests.

[0227] In some embodiments, transmitting additional system information using the other SI transmission management module 2015 may include at least one of transmitting system information indicating which RATs are available in an area and how a UE should select an available RAT, transmitting system information indicating which services are available in an area and how a UE should acquire the available services, transmitting system information regarding MBMS or PWS services, transmitting system information regarding location, positioning, or navigation services, or transmitting system information based at least in part on the determined location of the UE.

[0228] In some embodiments, receiving a request for additional system information using the SI request processing module 2010 may include receiving in the request one or more capabilities of the UE sending the request. In these embodiments, transmitting the additional system information using the other SI transmission management module 2015 may include transmitting the system information based at least in part on the one or more capabilities of the base station 105-i included in the request.

[0229] In some embodiments, receiving a request for additional system information using the SI request processing module 2010 may include receiving in the request a location of the UE sending the request. In these embodiments, the other SI transmission management module 2015 may identify the additional system information to transmit based at least in part on the location of the UE included in the request. Alternatively, the other SI transmission management module 2015 may determine the location of the UE sending the request and identify the additional system information to transmit based at least in part on the location of the UE.

[0230] In some embodiments, receiving the request for additional system information using the SI request processing module 2010 may include receiving in the request an identity of the UE sending the request. In these embodiments, the other SI transmission management module 2015 may identify the additional system information to transmit based at least in part on the identity of the UE included in the request. In some cases, the additional system information may be identified by accessing a database that includes the identity of the UE sending the request and one or more capabilities of the UE.

[0231] FIG. 21 shows a block diagram 2100 of a base station 105-j for use in wireless communications in accordance with various aspects of the present disclosure. The base station 105-j may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6 and 16-20. The base station 105-j may include a base station (or RRH) receiver module 1610-e, an SI transmission module 1620-e, or a base station (or RRH) transmitter module 1630-e, which may be examples of corresponding modules of the base station 105-e, 105-g, or 105-i (of FIG. 16, 18, or 20). The base station 105-j may also include a processor (not shown). Each of these components may be in communication with each other. The SI transmission module 1620-e may include a synchronization signal transmission management module 2105, a master SI transmission management module 2005-a, an SI request processing module 2010-a, or other SI transmission management modules 2015-a. The base station receiver module 1610-e and the base station transmitter module 1630-e may perform the functions of the base station receiver module 1610 and the base station transmitter module 1630 of FIG. 16, FIG. 18, or FIG. 20. In a configuration of the base station 105-j that includes one or more RRHs, one or more aspects of the modules 1610-e, 1620-e, or 1630-e may be transferred to each of the one or more RRHs.

[0232] The modules of base station 105-j may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0233] The synchronization signal transmission management module 2105 may be used to broadcast information on a downlink channel. This information may indicate that master system information (e.g., an MSIB) is to be transmitted in response to a master system information request received from a UE (e.g., an MSIB transmission request, such as the MSIB transmission request received at 415 in FIG. 4). In some examples, the downlink channel may include a synchronization signal (e.g., an instance of the periodic synchronization signal transmitted at 405 in FIG. 4). This information may be included in (or associated with) the synchronization signal.

[0234] The SI request processing module 2010-a may be used to receive a master system information request (e.g., according to information broadcast on a downlink channel). In some cases, receiving a master system information request may include receiving in the request an identification of one or more capabilities of the UE sending the request.

[0235] The master SI transmission management module 2005-a may be used to transmit master system information (e.g., master system information included in the MSIB received at 420 in FIG. 4) in response to receiving a master system information request. In some cases, the master system information may include system information that enables the UE to perform initial access of the network using one or more of network identification information, base station identification information, cell selection configuration and access constraints, or network access configuration.

[0236] The SI request processing module 2010-a may also be used to receive requests for additional system information (eg, the OSIB send request received at 430 in FIG. 4).

[0237] In some examples, the other SI transmission management module 2015-a may be used to transmit additional system information (e.g., non-master system information, such as other system information described with respect to FIG. 4) based at least in part on the request. In some cases, the additional system information may be identified based at least in part on one or more capabilities of the UE identified in the master system information request. The additional system information may also be identified based at least in part on the information received in the request.

[0238] In some embodiments, transmitting the first set of system information using the master SI transmission management module 2005-a may include transmitting an indication of one or more sets of additional system information that are available. In some embodiments, receiving the request for additional system information by the SI request processing module 2010-a may include receiving multiple requests for additional system information corresponding to multiple sets of additional system information to be transmitted. For example, the SI request processing module 2010-a may receive a single OSIB transmission request indicating one or more elements of additional system information that the UE wants to receive (e.g., a binary value in the OSIB transmission request may be set to true for each element of additional system information that the UE wants to receive). In other examples, the UE may request some type of additional system information in different OSIB transmission requests, and the SI request processing module 2010-a may receive multiple OSIB transmission requests.

[0239] FIG. 22 shows a block diagram 2200 of a base station 105-k for use in wireless communications in accordance with various aspects of the present disclosure. The base station 105-k may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6 and 16-21. The base station 105-k may include a base station (or RRH) receiver module 1610-f, an SI transmission module 1620-f, or a base station (or RRH) transmitter module 1630-f, which may be examples of corresponding modules of the base station 105-e (of FIG. 16). The base station 105-k may also include a processor (not shown). Each of these components may be in communication with one another. The SI transmission module 1620-f may include an SI transmission management module 2205 or an SI request processing module 2210. The base station receiver module 1610-f and the base station transmitter module 1630-f may perform the functions of the base station receiver module 1610 and the base station transmitter module 1630, respectively, of FIG. 16. Additionally, the base station receiver module 1610-f may be used to receive SI signals, such as the MSIB request to send signals 332, 345, 360, 415, or 615 of Figures 3A, 3B, 4, and 6, or the OSIB request to send 430 or 630 of Figures 4 and 6, and the base station transmitter module 1630-f may be used to transmit SI signals, value tags associated with the SI, or zone identifiers, such as the OSIBs 440, 445, 640, or 645 of Figures 4 and 6. In a configuration of the base station 105-k that includes one or more RRHs, one or more aspects of the modules 1610-f, 1620-f, or 1630-f may be transferred to each of the one or more RRHs.

[0240] The modules of base station 105-k may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0241] The SI transmission management module 2205 may be used to transmit a first signal (e.g., a synchronization signal or a paging message, such as an instance of the periodic synchronization signal or paging message transmitted at 605 of FIG. 6, or an MSIB transmitted at 620 of FIG. 6) from the base station to the UE. At the time of transmission of the first signal, the UE may communicate with the network using first system information. The first signal may include information to enable the UE to determine to request updated system information.

[0242] The SI request processing module 2210 may be used to receive a request from a UE for updated system information (e.g., an MSIB transmission request received at 615 in FIG. 6 or an OSIB transmission request received at 630 in FIG. 6).

[0243] The SI transmission management module 2205 may also be used to transmit updated system information (e.g., the MSIB transmitted at 620 of FIG. 6 or the OSIB transmitted at 640 or 645 of FIG. 6) based at least in part on the request.

[0244] In some embodiments, transmitting the first signal using the SI transmission management module 2205 may include transmitting a zone identifier (e.g., an area code, BSIC, or another cell identifier). In some cases, the zone identifier may be transmitted as part of the synchronization signal. In some cases, the zone identifier may identify one of the neighboring RATs of zones 510, 515, or 520 described with respect to FIG. 5.

[0245] FIG. 23 shows a block diagram 2300 of a base station 105-l for use in wireless communications in accordance with various aspects of the present disclosure. The base station 105-l may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6 and 16-22. The base station 105-l may include a base station (or RRH) receiver module 1610-g, an SI transmission module 1620-g, or a base station (or RRH) transmitter module 1630-g, which may be examples of corresponding modules of the base station 105-e, 105-g, or 105-k (of FIG. 16, 18, or 20). The base station 105-l may also include a processor (not shown). Each of these components may be in communication with each other. The SI transmission module 1620-g may include an SI transmission management module 2205-a or an SI request processing module 2210-a. The base station receiver module 1610-g and the base station transmitter module 1630-g may perform the functions of the base station receiver module 1610 and the base station transmitter module 1630 of Figure 16, Figure 18, Figure 20, or Figure 22. In a configuration of the base station 105-l that includes one or more RRHs, one or more aspects of the modules 1610-g, 1620-g, or 1630-g may be transferred to each of the one or more RRHs.

[0246] The modules of base station 105-1 may be implemented, individually or collectively, using one or more ASICs adapted to perform some or all of their functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) on one or more integrated circuits. In other examples, other types of integrated circuits (e.g., structured / platform ASICs, FPGAs, SoCs, or other semi-custom ICs) may be used that can be programmed in any manner known in the art. The functions of each module may also be implemented, in whole or in part, using instructions embodied in memory formatted for execution by one or more general-purpose or application-specific processors.

[0247] The SI transmission management module 2205-a may be used to transmit a first signal (e.g., a synchronization signal or paging message, such as an instance of the periodic synchronization signal or paging message transmitted at 605 of FIG. 6, or an MSIB transmitted at 620 of FIG. 6) from the base station to the UE. At the time of transmission of the first signal, the UE may communicate with the network using first system information. The first signal may include information to enable the UE to determine to request updated system information. The first signal may also include an indication that at least a portion of the first system information has changed.

[0248] The SI transmission management module 2205-a may include a modification flag or value tag transmission management module 2305. The modification flag or value tag transmission management module 2305 may, in some examples, be used to transmit one or more modification flags, each indicating via a counter value or Boolean variable (e.g., a binary value) that the corresponding portion of the first system information has changed. In some examples, the corresponding portion of the first system information may include a portion of the master system information, such as an MSIB or an element of the MSIB. In other examples, the corresponding portion of the first system information may include additional non-master system information, such as an OSIB or an element of the OSIB. The master system information may include one or more of identification information of the network, identification information of base stations in the network, cell selection configuration and access restrictions, or network access configuration information. The master system information may additionally or alternatively include one or more other elements of the master system information described, for example, with respect to FIG. 3A. The additional non-master system information may include one or more elements of the other system information described with respect to FIG. 4 or FIG. 6. In some embodiments, the modification flag may be transmitted along with (or as part of) the first signal.

[0249] The modification flag or value tag transmission management module 2305 may also, in some examples, be used to transmit one or more value tags corresponding to at least a portion (or various portions) of the changed first system information. In some examples, the one or more value tags may correspond to one or more portions of the master system information (e.g., one or more MSIBs, or one or more elements of one or more MSIBs), one or more portions of additional non-master system information (e.g., one or more OSIBs, or one or more elements of one or more OSIBs), or a combination thereof. The master system information may include one or more of: identification information of the network, identification information of base stations in the network, cell selection configuration and access restrictions, or network access configuration information. The master system information may additionally or alternatively include one or more other elements of the master system information described, for example, with respect to FIG. 3A. The additional non-master system information may include one or more elements of other system information described with respect to FIG. 4 or FIG. 6. In some embodiments, the one or more value tags may be transmitted along with (or as part of) the first signal.

[0250] The SI request processing module 2210-a may be used to receive requests from the UE for updated system information (e.g., to receive an MSIB transmission request at 615 of FIG. 6, to receive an OSIB transmission request at 630 of FIG. 6).

[0251] The SI transmission management module 2205-a may also be used to transmit updated system information (e.g., the MSIB transmitted at 620 in FIG. 6 or the OSIB transmitted at 640 or 645 in FIG. 6) based at least in part on the request.

[0252] 24A shows a block diagram 2400 of a base station 105-m (e.g., a base station forming part or all of an eNB) for use in wireless communications in accordance with various aspects of the present disclosure. In some examples, the base station 105-m may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6 and 16-23. The base station 105-m may be configured to implement or support at least some of the features and functionality of the base stations described with respect to FIGS. 1-6 and 14-19.

[0253] The base station 105-m may include a base station processor module 2410, a base station memory module 2420, at least one base station transceiver module (represented by a base station transceiver module 2450), at least one base station antenna (represented by a base station antenna 2455), or a base station SI transmit module 1620-h. The base station 105-m may also include one or more of a base station communication module 2430 or a network communication module 2440. Each of these components may be in communication with each other, directly or indirectly, through one or more buses 2435.

[0254] The base station memory module 2420 may include RAM or ROM. The base station memory module 2420 may store computer-readable computer-executable code 2425 including instructions that, when executed, are configured to cause the base station processor module 2410 to perform various functions described herein with respect to wireless communications, including, for example, transmitting synchronization signals. Alternatively, the code 2425 may not be directly executable by the base station processor module 2410, but may be configured (e.g., when compiled and executed) to cause the base station 105-m to perform various functions described herein.

[0255] The base station processor module 2410 may include an intelligent hardware device, e.g., a CPU, a microcontroller, an ASIC, etc. The base station processor module 2410 may process information received through the base station transceiver module 2450, the base station communication module 2430, or the network communication module 2440. The base station processor module 2410 may also process information to be transmitted to the transceiver module 2450 for transmission through a base station antenna 2455, to the base station communication module 2430 for transmission to one or more other base stations 105-n and 105-o, or to the network communication module 2440 for transmission to the core network 130-a, which may be an example of one or more aspects of the core network 130 described with respect to FIG. 1. The base station processor module 2410, alone or in conjunction with the base station SI transmission module 1620-h, may handle various aspects of communicating over (or managing communications over) the wireless medium.

[0256] The base station transceiver module 2450 may include a modem configured to modulate packets, provide the modulated packets to the base station antenna 2455 for transmission, and demodulate packets received from the base station antenna 2455. The base station transceiver module 2450, in some examples, may be implemented as one or more base station transmitter modules and one or more separate base station receiver modules. The base station transceiver module 2450 may support communication over one or more wireless channels. The base station transceiver module 2450 may be configured to communicate bidirectionally via the base station antenna 2455 with one or more UEs, such as one or more of the UEs 115 described with respect to FIG. 1, 2, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. For example, the base station 105-m may include multiple base station antennas 2455 (e.g., antenna arrays). The base station 105-m may communicate with the core network 130-a through the network communication module 2440. The base station 105-m may also communicate with other base stations, such as base stations 105-n and 105-o, using the base station communication module 2430.

[0257] The base station SI transmission module 1620-h may be configured to perform or control some or all of the base station features or functionality described with respect to FIGS. 1-6 and 14-19 related to transmitting system information. The base station SI transmission module 1620-h, or portions thereof, may include a processor, or some or all of the functionality of the base station SI transmission module 1620-h may be performed by or in association with the base station processor module 2410. In some examples, the base station SI transmission module 1620-h may be an example of the SI transmission module 1620 described with respect to FIGS. 16-19.

[0258] 24B shows a block diagram 2405 of a base station 105-p (e.g., a base station forming part or all of an eNB) for use in wireless communications in accordance with various aspects of the present disclosure. In some examples, the base station 105-p may be an example of one or more aspects of the base station 105 described with respect to FIGS. 1-6 and 16-23. The base station 105-p may be configured to implement or support at least some of the features and functionality of the base stations described with respect to FIGS. 1-6 and 16-23.

[0259] The base station 105-p may include a central node (or base station server) 2415 and one or more RRHs 2445. The central node 2415 may include a central node processor module 2410-a, a central node memory module 2420-a, a central node SI transmission module 1620-i, or an RRH interface module 2495. In some cases, the central node memory module 2420-a may include code 2425-a. The central node 2415 may also include one or more of a central node communication module 2430-a, which may communicate with one or more other central nodes, or which may communicate with a base station, such as base station 105-q or 105-r, or a network communication module 2440-a, which may communicate with the core network 130-b. Each of these components may be in communication with each other, directly or indirectly, through one or more buses 2435-a. The central node processor module 2410-a, central node memory module 2420-a, central node SI transmission module 1620-i, central node communication module 2430-a, network communication module 2440-a, and one or more buses 2435-a may perform the functions of the base station processor module 2410, base station memory module 2420, base station SI transmission module 1620, base station communication module 2430, network communication module 2440, and bus 2435, respectively, of FIG. 24A.

[0260] Each of the one or more RRHs 2445 may include a central node interface module 2490, at least one RRH transceiver module (represented by RRH transceiver module 2480), and at least one RRH antenna (represented by RRH antenna 2485). Each of these components may be in communication with one another directly or indirectly through one or more RRH buses 2475. The RRH transceiver module 2480 and the RRH antenna 2485 may perform the functions of the base station transceiver module 2450 and the base station antenna 2455, respectively, of FIG. 24A.

[0261] The RRH 2445 may also include one or more of an RRH processor module 2460, an RRH memory module 2465 (possibly storing code 2470), or an RRH SI transmit module 1620-j. Each of the RRH processor module 2460, the RRH memory module 2465, and the RRH SI transmit module 1620-j may communicate with other modules of the RRH 2445 via one or more buses 2475. In some examples, some of the functionality of the central node processor module 2410-a, the central node memory module 2420-a, or the central node SI transmit module 1620-i may be offloaded to (or replicated within) the RRH processor module 2460, the RRH memory module 2465, or the RRH SI transmit module 1620-j, respectively.

[0262] The RRH interface module 2495 and the central node interface module 2490 provide a communication interface between the central node 2415 and the RRH 2445 and may establish a bidirectional communication link 2498 between the central node 2415 and the RRH 2445. The communication link 2498 may be an optical communication link in some cases, but may take other forms.

[0263] The deployment of one or more RRHs 2445 in communication with the central node 2415 may be used, for example, to increase the coverage area of the base station 105-p or to place the central node 2415 and RRHs 2445 in a more useful location. For example, the RRHs 2445 may be placed in a location free of RF obstructions or on a smaller cell tower.

[0264] FIG. 25 is a block diagram of a MIMO communication system 2500 including a base station 105-s and a UE 115-m in accordance with various aspects of the present disclosure. The MIMO communication system 2500 may illustrate aspects of the wireless communication system 100 described with respect to FIG. 1. The base station 105-s may be an example of an aspect of the base station 105 described with respect to FIG. 1, 2, 4, 6, 16, 17, 18, 19, 20, 21, 22, 23, or 24. The base station 105-s may be equipped with antennas 2534-2535, and the UE 115-m may be equipped with antennas 2552-2553. In the MIMO communication system 2500, the base station 105-s may be capable of simultaneously transmitting data over multiple communication links. Each communication link may be referred to as a “layer,” and the “rank” of a communication link may indicate the number of layers used for communication. For example, in a 2×2 MIMO communication system in which the base station 105-s transmits two “layers,” the rank of the communication link between the base station 105-s and the UE 115-m is 2. In some examples, the MIMO communication system 2500 may be configured for communication using non-massive MIMO techniques. In other examples, the MIMO communication system 2500 may be configured for communication using massive MIMO techniques.

[0265] At the base station 105-s, the Tx processor 2520 may receive data from a data source. The transmit processor 2520 may process the data. The transmit processor 2520 may also generate control symbols or reference symbols. The transmit MIMO processor 2530 may perform spatial processing (e.g., precoding) on the data symbols, control symbols, or reference symbols, if applicable, and may provide output symbol streams to the transmit modulators 2532-2533. Each modulator 2532-2533 may process a respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 2532-2533 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink (DL) signal. In one example, the DL signals from the modulators 2532-2533 may be transmitted via the antennas 2534-2535, respectively.

[0266] UE 115-m may be an example of an aspect of UE 115 described with respect to FIG. 1, 2, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. At UE 115-m, UE antennas 2552-2553 may receive DL signals from base station 105-s and may provide received signals to modulators / demodulators 2554-2555, respectively. Each modulator / demodulator 2554-2555 may condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each modulator / demodulator 2554-2555 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 2556 may obtain received symbols from all modulators / demodulators 2554-2555, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive (Rx) processor 2558 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 115-m at a data output, and provide decoded control information to a processor 2580 or a memory 2582.

[0267] The processor 2580 may optionally execute stored instructions to instantiate an SI acquisition module 720-i, which may be an example of an aspect of the SI acquisition module 720 described with respect to FIGS.

[0268] On the uplink (UL), at the UE 115-m, a transmit processor 2564 may receive and process data from a data source. The transmit processor 2564 may also generate reference symbols for a reference signal. The symbols from the transmit processor 2564 may be precoded by a transmit MIMO processor 2566, further processed by demodulators / modulators 2554-2555 (e.g., for SC-FDMA, etc.), and transmitted to the base station 105-s in accordance with communication parameters received from the base station 105-s. At the base station 105-s, UL signals from the UE 115-m may be received by antennas 2534-2535, processed by demodulators 2532-2533, detected by a MIMO detector 2536, and further processed by a receive processor 2538. The receive processor 2538 may provide decoded data to a data output and to a processor 2540 or a memory 2542.

[0269] The processor 2540 may, in some cases, execute the stored instructions to instantiate the SI transmission module 1620-k, which may be an example of an aspect of the SI transmission module 1620 described with respect to FIGS.

[0270] The components of the UE 115-m, individually or collectively, may be implemented using one or more ASICs adapted to perform some or all of the applicable functions in hardware. Each of the mentioned modules may be a means for performing one or more functions related to the operation of the MIMO communications system 2500. Similarly, the components of the base station 105-s, individually or collectively, may be implemented using one or more ASICs adapted to perform some or all of the applicable functions in hardware. Each of the mentioned components may be a means for performing one or more functions related to the operation of the MIMO communications system 2500.

[0271] 26 is a flowchart illustrating an example of a method 2600 for wireless communication in a UE, in accordance with various aspects of the present disclosure. For clarity, the method 2600 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-8, 15, or 25. In some examples, the UE may execute one or more sets of code for controlling functional elements of the UE to perform functions described below. In some examples, the method 2600 may be performed by the UE during an initial access procedure.

[0272] In block 2605, the UE may receive a first signal, the first signal including an indication of whether SI should be requested by the UE. The first signal, in some examples, may be a periodic synchronization signal and may indicate to the UE that SI should be acquired through fixed, periodic broadcast or broad-beam transmission, or through on-demand broadcast, unicast, broad-beam, or narrow-beam transmission. The operations in block 2605 may be performed using the SI acquisition module 720 described with reference to FIG. 7, FIG. 8, FIG. 15, or FIG. 25, the SI acquisition mode module 735 described with reference to FIG. 7 or FIG. 8, or the synchronization signal reception module 805 described with reference to FIG. 8.

[0273] In block 2610, the UE may acquire SI according to the above instructions. Thus, if the above instructions indicate that SI should be broadcast without the UE requesting it, the UE may receive the SI in a periodic broadcast or broad-beam transmission. If the above instructions indicate that SI should be transmitted in response to a UE request, the UE may receive the SI after the UE issues a request for it. The operation in block 2610 may be performed using the SI acquisition module 720 described with reference to FIG. 7, FIG. 8, FIG. 15, or FIG. 25, or the SI reception module 745 described with reference to FIG. 7 or FIG. 8.

[0274] Thus, method 2600 may provide wireless communication, and in particular SI acquisition. Note that method 2600 is just one implementation, and that the operations of method 2600 may be rearranged or otherwise modified such that other implementations are possible.

[0275] 27 is a flowchart illustrating an example of a method 2700 for wireless communication in a UE, in accordance with various aspects of the present disclosure. For clarity, the method 2700 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-8, 15, or 25. In some examples, the UE may execute one or more sets of code for controlling functional elements of the UE to perform functions described below. In some examples, the method 2700 may be performed by the UE during an initial access procedure.

[0276] In block 2705, the UE may receive a first signal, the first signal including an indication of whether SI should be requested by the UE. The first signal, in some examples, may be a periodic synchronization signal and may indicate to the UE that SI should be acquired through on-demand broadcast, unicast, broad-beam transmission, or narrow-beam transmission. The operations in block 2705 may be performed using the SI acquisition module 720 described with reference to FIG. 7, FIG. 8, FIG. 15, or FIG. 25, the SI acquisition mode module 735 described with reference to FIG. 7 or FIG. 8, or the synchronization signal reception module 805 described with reference to FIG. 8.

[0277] In block 2710, the UE may transmit a request for SI according to the above instructions. The request may be transmitted according to information included in the first signal, such as destination and / or timing information. The operations in block 2710 may be performed using the SI acquisition module 720 described with reference to FIG. 7, FIG. 8, FIG. 15, or FIG. 25, or the UE SI request module 740 described with reference to FIG. 7 or FIG. 8.

[0278] In block 2715, the UE may receive SI in response to the request. The SI may be received as an on-demand periodic broadcast or broad-beam transmission, an on-demand irregular broadcast or broad-beam transmission, or an on-demand irregular unicast or narrow-beam transmission. The operations in block 2715 may be performed using the SI acquisition module 720 described with reference to FIG. 7, FIG. 8, FIG. 15, or FIG. 25, or the SI reception module 745 described with reference to FIG. 7 or FIG. 8.

[0279] Thus, method 2700 may provide wireless communication, and in particular SI acquisition. Note that method 2700 is just one implementation, and that the operations of method 2700 may be rearranged or otherwise modified such that other implementations are possible.

[0280] 28 is a flowchart illustrating an example of a method 2800 for wireless communication in a UE, in accordance with various aspects of the present disclosure. For clarity, the method 2800 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-8, 15, or 25. In some examples, the UE may execute one or more sets of code for controlling functional elements of the UE to perform functions described below. In some examples, the method 2800 may be performed by the UE during an initial access procedure.

[0281] In block 2805, the UE may receive a first signal, the first signal including an indication of whether SI should be requested by the UE. The first signal, in some examples, may be a periodic synchronization signal and may indicate to the UE that SI should be transmitted without the UE having to request SI. The operations in block 2805 may be performed using the SI acquisition module 720 described with reference to FIG. 7, FIG. 8, FIG. 15, or FIG. 25, the SI acquisition mode module 735 described with reference to FIG. 7 or FIG. 8, or the synchronization signal reception module 805 described with reference to FIG. 8.

[0282] In block 2810, the UE may receive SI via a second signal according to the instructions above, where the second signal is transmitted via broadcast or broad-beam operation. The SI may be received as a fixed, periodic broadcast or broad-beam transmission. The operations in block 2810 may be performed using the SI acquisition module 720 described with reference to FIG. 7, FIG. 8, FIG. 15, or FIG. 25, or the SI reception module 745 described with reference to FIG. 7 or FIG. 8.

[0283] Thus, method 2800 may provide wireless communication, and in particular SI acquisition. Note that method 2800 is just one implementation, and that the operations of method 2800 may be rearranged or otherwise modified such that other implementations are possible.

[0284] 29 is a flowchart illustrating an example of a method 2900 for wireless communication in a base station in accordance with various aspects of the present disclosure. For clarity, the method 2900 is described below with reference to one or more aspects of the base station 105 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25. In some examples, the base station may execute one or more sets of code for controlling functional elements of the base station to perform functions described below. In some examples, the method 2900 may be performed by the base station during an initial access procedure of a UE.

[0285] In block 2905, the base station may transmit a first signal, the first signal including an indication of whether SI should be requested by the UE. The first signal, in some examples, may be a periodic synchronization signal indicating to the UE that SI should be acquired through fixed, periodic broadcast or broad-beam transmission, or through on-demand broadcast, unicast, broad-beam, or narrow-beam transmission. The operations in block 2905 may be performed using the SI transmission module 1620 described with reference to FIG. 16, 17, 24A, 24B, or 25, the SI transmission mode module 1635 described with reference to FIG. 16 or 17, or the synchronization signal transmission module 1705 described with reference to FIG. 17.

[0286] In block 2910, the base station may transmit the SI according to the above instruction. Thus, if the above instruction indicates that the SI should be broadcast without the UE requesting the SI, the base station may transmit the SI in a regular broadcast or broad-beam transmission. If the above instruction indicates that the SI should be transmitted in response to a UE request, the base station may transmit the SI after the UE issues a request for the SI. The operation in block 2910 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, or the SI transmission module 1645 described with reference to FIG. 16 or FIG. 17.

[0287] Thus, method 2900 may provide wireless communication, and in particular SI transmission. Note that method 2900 is just one implementation, and that the operations of method 2900 may be rearranged or otherwise modified such that other implementations are possible.

[0288] 30 is a flowchart illustrating an example of a method 3000 for wireless communication in a base station in accordance with various aspects of the present disclosure. For clarity, the method 3000 is described below with reference to one or more aspects of the base station 105 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25. In some examples, the base station may execute one or more sets of code for controlling functional elements of the base station to perform functions described below. In some examples, the method 3000 may be performed by the base station during an initial access procedure of a UE.

[0289] In block 3005, the base station may transmit a first signal, the first signal including an indication of whether SI should be requested by the UE. The first signal, in some examples, may be a periodic synchronization signal and may indicate to the UE that SI should be acquired through on-demand broadcast, unicast, broad-beam transmission, or narrow-beam transmission. The operations in block 3005 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, the SI transmission mode module 1635 described with reference to FIG. 16 or FIG. 17, or the synchronization signal transmission module 1705 described with reference to FIG. 17.

[0290] In block 3010, the base station may receive a request for SI according to the above instructions. The request may be received according to information included in the first signal, such as destination and / or timing information. The operations in block 3010 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, or the base station SI request module 1640 described with reference to FIG. 16 or FIG. 17.

[0291] In block 3015, the base station may transmit SI in response to the request. The SI may be transmitted as an on-demand periodic broadcast or broad-beam transmission, an on-demand irregular broadcast or broad-beam transmission, or an on-demand irregular unicast or narrow-beam transmission. The operations in block 3015 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, or the SI transmission module 1645 described with reference to FIG. 16 or FIG. 17.

[0292] Thus, method 3000 may provide wireless communication, and in particular SI transmission. Note that method 3000 is just one implementation, and that operations of method 3000 may be rearranged or otherwise modified such that other implementations are possible.

[0293] 31 is a flowchart illustrating an example of a method 3100 for wireless communication in a base station in accordance with various aspects of the present disclosure. For clarity, the method 3100 is described below with reference to one or more aspects of the base station 105 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25. In some examples, the base station may execute one or more sets of code for controlling functional elements of the base station to perform functions described below. In some examples, the method 3100 may be performed by the base station during an initial access procedure of a UE.

[0294] In block 3105, the base station may transmit a first signal, the first signal including an indication of whether SI should be requested by the UE. The first signal, in some examples, may be a periodic synchronization signal and may indicate to the UE that SI should be transmitted without the UE having to request SI. The operations in block 3105 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, the SI transmission mode module 1635 described with reference to FIG. 16 or FIG. 17, or the synchronization signal transmission module 1705 described with reference to FIG. 17.

[0295] In block 3110, the base station can transmit the SI via a second signal according to the above instructions, where the second signal is transmitted via broadcast or broad beam operation. The SI can be transmitted as a fixed, periodic broadcast or broad beam transmission. The operations in block 3110 can be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, or the SI transmission module 1645 described with reference to FIG. 16 or FIG. 17.

[0296] Thus, method 3100 may provide wireless communication, and in particular SI transmission. Note that method 3100 is just one implementation, and that operations of method 3100 may be rearranged or otherwise modified such that other implementations are possible.

[0297] 32 is a flowchart illustrating an example of a method 3200 for wireless communication in a base station in accordance with various aspects of the present disclosure. For clarity, the method 3200 is described below with reference to one or more aspects of the base station 105 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25. In some examples, the base station may execute one or more sets of code for controlling functional elements of the base station to perform functions described below. In some examples, the method 3200 may be performed by the base station during an initial access procedure of a UE.

[0298] In block 3205, the base station may transmit a first signal, the first signal including an indication of whether SI should be requested by the UE. The first signal, in some examples, may be a periodic synchronization signal and may indicate to the UE that SI should be acquired through fixed, periodic broadcast or broad-beam transmission, or through on-demand broadcast, unicast, broad-beam, or narrow-beam transmission. The operations in block 3205 may be performed using the SI transmission module 1620 described with reference to FIG. 16, 17, 24A, 24B, or 25, or the SI transmission mode module 1635 described with reference to FIG. 16 or 17.

[0299] In block 3210, the base station may transmit the SI according to the above instruction and transmission mode. Thus, if the instruction and transmission mode indicate that the SI should be broadcast without the UE requesting it, the base station may transmit the SI in a periodic broadcast or broad beam transmission. If the instruction and transmission mode indicate that the SI should be transmitted in response to a UE request, the base station may transmit the SI after the UE issues a request for the SI. Depending on the transmission mode, the base station may transmit the SI as either a fixed periodic broadcast or broad beam transmission, an on-demand periodic broadcast or broad beam transmission, an on-demand irregular broadcast or broad beam transmission, or an on-demand irregular unicast or narrow beam transmission. The operation in block 3210 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, or the SI transmission module 1645 described with reference to FIG. 16 or FIG. 17.

[0300] The base station may change the transmission mode in block 3215, 3220, 3225, or 3230. Thus, the base station may perform any one or more of blocks 3215, 3220, 3225, or 3230. The change in transmission mode may be made in response to, for example, a change in the number of UEs requesting SI from the base station, network load, congestion conditions, or available radio resources.

[0301] In block 3215, the base station may change the transmission mode to a broadcast or broad-beam mode that targets the cell edge and has fixed periodic scheduling. The change in transmission mode may be based on one or more of the number of UEs requesting SI acquisition, network load, congestion, or available radio resources. The operation in block 3215 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, the SI transmission mode module 1635 described with reference to FIG. 16 or FIG. 17, or the SI transmission mode determination module 1710 described with reference to FIG. 17.

[0302] In block 3220, the base station may change the transmission mode to a broadcast or broad-beam mode targeted at the cell edge and with on-demand periodic scheduling triggered by requests for system information according to the instructions above. The change in transmission mode may be based on one or more of the number of UEs requesting SI acquisition, network load, congestion, or available radio resources. The operation in block 3220 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, the SI transmission mode module 1635 described with reference to FIG. 16 or FIG. 17, or the SI transmission mode determination module 1710 described with reference to FIG. 17.

[0303] In block 3225, the base station may change the transmission mode to a broadcast or broad-beam mode with on-demand, irregular scheduling triggered by a request for system information according to the instructions above. The change in transmission mode may be based on one or more of the number of UEs requesting SI acquisition, network load, congestion, or available radio resources. The operation in block 3225 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, the SI transmission mode module 1635 described with reference to FIG. 16 or FIG. 17, or the SI transmission mode determination module 1710.

[0304] In block 3230, the base station may change the transmission mode to be unicast or narrow beam mode with on-demand, non-periodic scheduling triggered by a request for system information according to the above instructions. The change in transmission mode may be based on one or more of the number of UEs requesting SI acquisition, network load, congestion, or available radio resources. The operation in block 3230 may be performed using the SI transmission module 1620 described with reference to FIG. 16, FIG. 17, FIG. 24A, FIG. 24B, or FIG. 25, the SI transmission mode module 1635 described with reference to FIG. 16 or FIG. 17, or the SI transmission mode determination module 1710 described with reference to FIG. 17.

[0305] The operations in blocks 3215, 3220, 3225, 3230 may all be performed by a base station. Alternatively, a base station may perform any one or more of the operations described in blocks 3215, 3220, 3225, 3230.

[0306] Thus, method 3200 may provide wireless communication, and in particular SI transmission. Note that method 3200 is just one implementation, and that the operations of method 3200 may be rearranged or otherwise modified such that other implementations are possible.

[0307] 33 is a flowchart illustrating an example of a method 3300 for wireless communication in a UE according to various aspects of the present disclosure. For clarity, the method 3300 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-15 and 25. In some examples, the UE may execute one or more sets of codes for controlling functional elements of the UE to perform functions described below. In some examples, the method 3300 may be performed by the UE receiving system information in a unicast, narrow beam, broadcast, or broad beam manner.

[0308] In block 3305, the UE may receive a first signal comprising a first instruction, the first instruction being associated with acquiring system information. The first instruction may indicate, for example, that the system information should be acquired via a request or a broadcast. The operations in block 3305 may be performed using the SI acquisition module 720 described with reference to FIG. 9, 10, 15, or 25, the service-specific SI acquisition mode module 905 described with reference to FIG. 9 or 10, or the synchronization signal reception module 1005 described with reference to FIG. 10.

[0309] In block 3310, the UE may identify one or more services for which system information is to be acquired. Available service-specific system information may be identified in the first signal. The UE may still determine which of the identified service-specific system information is needed. Alternatively, the UE may determine which system information is needed when there is nothing identifying available service-specific system information. The operation in block 3310 may be performed using the SI acquisition module 720 described with reference to FIG. 9, FIG. 10, FIG. 15, or FIG. 25, the service-specific SI acquisition mode module 905 described with reference to FIG. 9 or FIG. 10, or the service-specific SI acquisition mode determination module 1010 described with reference to FIG. 10.

[0310] In block 3315, the UE may acquire system information for the identified one or more services according to the first instruction. The system information may be acquired either by listening to a broadcast or by requesting service-specific system information. The operations in block 3315 may be performed using the SI acquisition module 720 described with reference to FIG. 9, FIG. 10, FIG. 15, or FIG. 25, or the UE service-specific SI request module 910 and SI reception module 745 described with reference to FIG. 9 or FIG. 10.

[0311] In some embodiments of method 3300, obtaining the system information may include sending a request for system information for one or more services and receiving the system information for the one or more services in response to the request. In other embodiments, obtaining the system information may include sending a separate request for system information for each of the one or more services, each request being for system information for a different service, and individually receiving the system information for the one or more services in response to each of the requests.

[0312] In some embodiments, receiving the first signal may include receiving a second indication that system information for one or more services is to be broadcast at one or more predetermined times and on one or more predetermined channels. Receiving the first signal may also include receiving a second indication that system information for one or more services is available.

[0313] Thus, the method 3300 may provide wireless communication. Note that the method 3300 is just one implementation and that the operations of the method 3300 may be rearranged or otherwise modified such that other implementations are possible.

[0314] 34 is a flowchart illustrating an example of a method 3400 for wireless communication in a UE according to various aspects of the present disclosure. For clarity, the method 3400 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-15 and 25. In some examples, the UE may execute one or more sets of codes for controlling functional elements of the UE to perform the functions described below. In some examples, the method 3400 may be performed by the UE receiving system information in a unicast, narrow beam, broadcast, or broad beam manner.

[0315] In block 3405, the UE may receive a first signal comprising a first instruction, the first instruction being associated with acquiring system information. The first instruction may indicate, for example, that the system information should be acquired via a request or a broadcast. The operations in block 3405 may be performed using the SI acquisition module 720 described with reference to FIG. 9, 10, 15, or 25, the service-specific SI acquisition mode module 905 described with reference to FIG. 9 or 10, or the synchronization signal reception module 1005 described with reference to FIG. 10.

[0316] In block 3410, the UE may identify one or more services for which system information is to be acquired. Available service-specific system information may be identified in the first signal. The UE may still determine which of the identified service-specific system information is needed. Alternatively, the UE may determine which system information is needed when there is nothing identifying available service-specific system information. The operation in block 3410 may be performed using the SI acquisition module 720 described with reference to FIG. 9, FIG. 10, FIG. 15, or FIG. 25, the service-specific SI acquisition mode module 905 described with reference to FIG. 9 or FIG. 10, or the service-specific SI acquisition mode determination module 1010 described with reference to FIG. 10.

[0317] Depending on the first instruction included in the first signal, any one of blocks 3415, 3420, or 3425 may follow block 3410. In block 3415, the UE may acquire system information for the identified one or more services by sending a request that explicitly identifies one or more services for which system information is to be acquired. The operations in block 3415 may be performed using the SI acquisition module 720 described in connection with FIG. 9, FIG. 10, FIG. 15, or FIG. 25, or the UE service-specific SI request module 910 and SI receiving module 745 described in connection with FIG. 9 or FIG. 10.

[0318] In block 3420, the UE may obtain system information for the identified one or more services by sending a separate request for system information for each of the one or more services for which system information is to be obtained. The operations in block 3420 may be performed using the SI acquisition module 720 described in connection with FIG. 9, FIG. 10, FIG. 15, or FIG. 25, or the UE service-specific SI request module 910 and SI receiving module 745 described in connection with FIG. 9 or FIG. 10.

[0319] In block 3425, the UE may acquire system information for the identified one or more services by listening to one or more broadcasts including system information for the one or more services for which system information is to be acquired. The operations in block 3425 may be performed using the SI acquisition module 720 described with respect to FIG. 9, FIG. 10, FIG. 15, or FIG. 25, or the SI receiving module 745 described with respect to FIG. 9 or FIG. 10.

[0320] Thus, method 3400 may provide wireless communication. Note that method 3400 is just one implementation and that the operations of method 3400 may be rearranged or otherwise modified such that other implementations are possible.

[0321] 35 is a flowchart illustrating an example of a method 3500 for wireless communication in a base station, in accordance with various aspects of the present disclosure. For clarity, the method 3500 is described below with reference to one or more aspects of the base station 105 described with reference to FIGS. 1-6 and 16-25. In some examples, the base station may execute one or more sets of code for controlling functional elements of the base station to perform functions described below. In some examples, the method 3500 may be performed by the base station during an initial access procedure of a UE.

[0322] In block 3505, the base station may transmit a first signal comprising a first instruction associated with acquiring system information by the UE for one or more services. The first signal, in some examples, may be a service-specific periodic synchronization signal and may indicate to the UE that service-specific SI should be acquired through a fixed periodic broadcast, through a broad beam transmission, or by request. The operations in block 3505 may be performed using the SI transmission module 1620 described with reference to FIG. 18, 19, 24A, 24B, or 25, or the service-specific SI transmission mode module 1805 described with reference to FIG. 18 or 19.

[0323] In block 3510, the base station may transmit system information associated with the available services to the UE according to the first instruction, with separate transmissions being used to transmit system information for different services and different configurations of the services. These service-specific SI transmissions may be broadcast periodically or may be transmitted in response to receiving a request from the UE. The operations in block 3510 may be performed using the SI transmission module 1620 described with reference to FIG. 18, 19, 24A, 24B, or 25, or the base station service-specific SI request module 1810 and SI transmission module 1645 described with reference to FIG. 18 or 19.

[0324] In some embodiments, the base station may further receive a request for system information for one or more services according to the first indication, and then transmit the system information for the one or more services in response to the request. In other embodiments, the base station may receive multiple requests for system information for one or more services according to the first indication, each request from the UE and for system information of a different service, and then transmit the system information for the one or more services in response to the request. The service-specific system information may be transmitted as a joint transmission or separately.

[0325] In some embodiments, the base station can include in the first signal a second indication that system information for one or more services is to be broadcast at one or more predetermined times and on one or more predetermined channels. Additionally, the base station can include in the first signal a second indication that system information for one or more services is available to be requested.

[0326] Thus, method 3500 may provide wireless communication, and in particular service-specific SI transmission. Note that method 3500 is just one implementation, and that the operations of method 3500 may be rearranged or otherwise modified such that other implementations are possible.

[0327] 36 is a flowchart illustrating an example of a method 3600 for wireless communication in a base station, in accordance with various aspects of the present disclosure. For clarity, the method 3600 is described below with reference to one or more aspects of the base station 105 described with reference to FIGS. 1-6 and 16-25. In some examples, the base station may execute one or more sets of code for controlling functional elements of the base station to perform functions described below. In some examples, the method 3600 may be performed by the base station during an initial access procedure of a UE.

[0328] In block 3605, the base station may transmit a first signal comprising a first instruction associated with acquiring system information by the UE for one or more services. The first signal, in some examples, may be a service-specific periodic synchronization signal and may indicate to the UE that service-specific SI should be acquired through a fixed periodic broadcast, through a broad beam transmission, or by request. The operations in block 3605 may be performed using the SI transmission module 1620 described with reference to FIG. 18, 19, 24A, 24B, or 25, or the service-specific SI transmission mode module 1805 described with reference to FIG. 18 or 19.

[0329] Depending on the first instruction included in the first signal, block 3605 may be followed by any one of blocks 3610, 3615, or 3620. In block 3610, the base station may receive a request that explicitly identifies one or more services for which system information is to be obtained. The base station may then transmit the requested system information. The operations in block 3610 may be performed using the SI transmission module 1620 described in connection with FIG. 18, FIG. 19, FIG. 24A, FIG. 24B, or FIG. 25, or the base station service-specific SI request module 1810 and SI transmission module 1645 described in connection with FIG. 18 or FIG. 19.

[0330] In block 3615, the base station may receive a separate request for system information for each of one or more services for which system information is to be obtained. The base station may then transmit the requested system information. The operations in block 3615 may be performed using the SI transmission module 1620 described with reference to FIG. 18, 19, 24A, 24B, or 25, or the base station service-specific SI request module 1810 and SI transmission module 1645 described with reference to FIG. 18 or 19.

[0331] In block 3620, the base station may periodically broadcast service-specific system information. The periodic broadcast may be in accordance with information included in the first signal. The operations in block 3620 may be performed using the SI transmission module 1620 described with respect to FIG. 18, FIG. 19, FIG. 24A, FIG. 24B, or FIG. 25, or the SI transmission module 1645 described with respect to FIG. 18 or FIG. 19.

[0332] Thus, method 3600 may provide wireless communication, and in particular service-specific SI transmission. Note that method 3600 is just one implementation, and that operations of method 3600 may be rearranged or otherwise modified such that other implementations are possible.

[0333] 37 is a flowchart illustrating an example of a method 3700 for wireless communication in a UE according to various aspects of the present disclosure. For clarity, the method 3700 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-15 and 25. In some examples, the UE may execute one or more sets of codes for controlling functional elements of the UE to perform functions described below. In some examples, the method 3700 may be performed by the UE receiving system information in a unicast, narrow beam, broadcast, or broad beam manner.

[0334] In block 3705, the UE may receive a first set of system information (e.g., master system information such as master system information included in an MSIB). The operations in block 3705 may be performed using the SI acquisition module 720 described with respect to FIG. 11, 12, 15, or 25, or the master SI acquisition module 1105 described with respect to FIG. 11 or 12.

[0335] In block 3710, the UE may determine, based at least in part on the first set of system information, that additional system information (e.g., non-master system information such as information included in the OSIB) is available. The operations in block 3710 may be performed using the SI acquisition module 720 described with respect to FIG. 11, 12, 15, or 25, or the SI processing module 1110 described with respect to FIG. 11 or 12.

[0336] At block 3715, the UE may transmit a request for additional system information (e.g., an OSIB transmission request). In some examples, the UE may transmit multiple requests for additional system information. In some examples, a single OSIB transmission request may indicate one or more elements of additional system information that the UE wants to receive (e.g., a binary value in the OSIB transmission request may be set to true for each element of additional system information that the UE wants to receive). In other examples, the UE may request several types of additional system information in different OSIB transmission requests, and multiple OSIB transmission requests may be transmitted. The operations at block 3715 may be performed using the SI acquisition module 720 described in connection with FIG. 11, 12, 15, or 25, or the UE SI request module 1115 described in connection with FIG. 11 or 12.

[0337] The UE may receive additional system information at block 3720. The operations at block 3720 may be performed using the SI acquisition module 720 described with respect to Figure 11, 12, 15, or 25, or another SI acquisition module 1120 described with respect to Figure 11 or 12.

[0338] In some embodiments of method 3700, receiving the first set of system information may include receiving an indication of one or more sets of additional system information that are available. In some embodiments of method 3700, transmitting the request for the additional system information may include specifying the one or more sets of additional system information in the request for the additional system information. In some embodiments, the one or more sets of additional system information specified in the request for the additional system information may include the one or more sets of additional system information indicated in the first set of system information.

[0339] In some embodiments of method 3700, receiving additional system information at block 3720 may include at least one of receiving system information indicating which RATs are available in an area and how a UE should select an available RAT, receiving system information indicating which services are available in an area and how a UE should acquire the available services, receiving system information regarding MBMS or PWS services, receiving system information regarding location, positioning, or navigation services, or receiving system information based at least in part on a determined location of the UE.

[0340] In some embodiments of method 3700, transmitting the request for the additional system information may include including one or more capabilities of the UE in the request. In these embodiments, receiving the additional system information may include receiving the system information based at least in part on the one or more capabilities of the UE included in the request.

[0341] In some embodiments of method 3700, transmitting the request for the additional system information may include including the location of the UE in the request. In these embodiments, receiving the additional system information may include receiving the system information based at least in part on the location of the UE included in the request.

[0342] In some embodiments of method 3700, transmitting the request for the additional system information may include including an identification of the UE in the request. In these embodiments, receiving the additional system information may include receiving the additional system information based at least in part on the identification of the UE included in the request.

[0343] Thus, the method 3700 may provide wireless communication. Note that the method 3700 is just one implementation and that the operations of the method 3700 may be rearranged or otherwise modified such that other implementations are possible.

[0344] 38 is a flowchart illustrating an example of a method 3800 for wireless communication in a UE in accordance with various aspects of the present disclosure. For clarity, the method 3800 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-15 and 25. In some examples, the UE may execute one or more sets of code for controlling functional elements of the UE to perform functions described below. In some examples, the method 3800 may be performed by the UE receiving system information in a unicast, narrow beam, broadcast, or broad beam manner.

[0345] In block 3805, the UE may decode information received from the downlink channel. The decoded information may indicate that master system information (e.g., an MSIB) is received in response to a master system information request (e.g., an MSIB transmission request). In some examples, the downlink channel may include a synchronization signal. The decoded information may include information decoded from the synchronization signal. The operations in block 3805 may be performed using the SI acquisition module 720 described with reference to FIG. 11, 12, 15, or 25, or the synchronization signal processing module 1205 described with reference to FIG. 12.

[0346] In block 3810, the UE may transmit a master system information request according to information decoded from the downlink channel. The operations in block 3810 may be performed using the SI acquisition module 720 described with reference to FIG. 11, 12, 15, or 25, or the UE SI request module 1115 described with reference to FIG. 11 or 12.

[0347] In block 3815, the UE may receive master system information. The master system information may include system information that enables the UE to perform initial access of the network using one or more of an identification of the network, an identification of a base station in the network, a cell selection configuration and access restrictions, or a network access configuration. The operations in block 3815 may be performed using the SI acquisition module 720 described with reference to FIG. 11, 12, 15, or 25, or the master SI acquisition module 1105 described with reference to FIG. 11 or 12.

[0348] The UE may determine, based at least in part on the master system information, that additional system information is available at block 3820. The operations at block 3820 may be performed using the SI acquisition module 720 described with respect to Figure 11, 12, 15, or 25, or the SI processing module 1110 described with respect to Figure 11 or 12.

[0349] At block 3825, the UE may transmit a request for additional system information (e.g., an OSIB transmission request). In some examples, the UE may transmit multiple requests for additional system information. In some examples, a single OSIB transmission request may indicate one or more elements of additional system information that the UE wants to receive (e.g., a binary value in the OSIB transmission request may be set to true for each element of additional system information that the UE wants to receive). In other examples, the UE may request several types of additional system information in different OSIB transmission requests, and multiple OSIB transmission requests may be transmitted. The operations at block 3825 may be performed using the SI acquisition module 720 described in connection with FIG. 11, 12, 15, or 25, or the UE SI request module 1115 described in connection with FIG. 11 or 12.

[0350] The UE may receive additional system information at block 3830. The operations at block 3830 may be performed using the SI acquisition module 720 described with respect to FIG. 11, 12, 15, or 25, or another SI acquisition module 1120 described with respect to FIG. 11 or 12.

[0351] In some embodiments of method 3800, receiving the master system information may include receiving an indication of one or more sets of additional system information that are available. In some embodiments of method 3800, sending the request for the additional system information may include specifying the one or more sets of additional system information in the request for the additional system information. In some embodiments, the one or more sets of additional system information specified in the request for the additional system information may include the one or more sets of additional system information indicated in the master system information.

[0352] Thus, the method 3800 may provide wireless communication. Note that the method 3800 is just one implementation and that the operations of the method 3800 may be rearranged or otherwise modified such that other implementations are possible.

[0353] 39 is a flowchart illustrating an example of a method 3900 for wireless communication in a base station in accordance with various aspects of the present disclosure. For clarity, the method 3900 is described below with reference to one or more aspects of the base station 105 described with reference to FIGS. 1-6 and 16-25. In some examples, the base station may execute one or more sets of code for controlling functional elements of the base station to perform functions described below. In some examples, the method 3900 may be performed by the base station transmitting system information in a unicast, narrow beam, broadcast, or broad beam manner.

[0354] The base station may transmit a first set of system information (e.g., master system information such as master system information included in an MSIB) in block 3905. The operations in block 3905 may be performed using the SI transmission module 1620 described with reference to FIG. 20, 21, 24A, 24B, or 25, or the master SI transmission management module 2005 described with reference to FIG. 20 or 21.

[0355] The base station may receive a request for additional system information (e.g., non-master system information, such as information contained in an OSIB) in block 3910. The operations in block 3910 may be performed using the SI transmission module 1620 described with respect to Figure 20, Figure 21, Figure 24A, Figure 24B, or Figure 25, or the SI request processing module 2010 described with respect to Figure 20 or Figure 21.

[0356] The base station may transmit additional system information based at least in part on the request in block 3915. The operations in block 3915 may be performed using the SI transmission module 1620 described with respect to FIG. 20, FIG. 21, FIG. 24A, FIG. 24B, or FIG. 25, or other SI transmission management module 2015 described with respect to FIG. 20 or FIG. 21.

[0357] In some embodiments of method 3900, transmitting the first set of system information may include transmitting an indication of one or more sets of additional system information that are available. In some embodiments of method 3900, receiving the request for the additional system information may include receiving multiple requests for the additional system information corresponding to multiple sets of additional system information to be transmitted. For example, method 3900 may include receiving a single OSIB transmission request indicating one or more elements of the additional system information that the UE wants to receive (e.g., a binary value in the OSIB transmission request may be set to true for each element of the additional system information that the UE wants to receive). In other examples, method 3900 may include receiving requests for several types of additional system information in different OSIB transmission requests.

[0358] In some embodiments of method 3900, transmitting additional system information in block 3915 may include at least one of transmitting system information indicating which RATs are available in an area and how a UE should select an available RAT, transmitting system information indicating which services are available in an area and how a UE should acquire the available services, transmitting system information regarding MBMS or PWS services, transmitting system information regarding location, positioning, or navigation services, or transmitting system information based at least in part on a determined location of the UE.

[0359] In some embodiments of the method 3900, receiving the request for the additional system information may include receiving in the request one or more capabilities of the UE sending the request. In these embodiments, transmitting the additional system information may include transmitting the system information based at least in part on the one or more capabilities of the UE included in the request.

[0360] In some embodiments of the method 3900, receiving the request for the additional system information may include receiving in the request a location of the UE sending the request. In these embodiments, the method 3900 may include identifying the additional system information to transmit based at least in part on the location of the UE included in the request. Alternatively, the method 3900 may include determining a location of the UE sending the request and identifying the additional system information to transmit based at least in part on the location of the UE.

[0361] In some embodiments of the method 3900, receiving the request for the additional system information may include receiving in the request an identity of the UE sending the request. In these embodiments, the method 3900 may include identifying the additional system information to send based at least in part on the identity of the UE included in the request. In some cases, the additional system information may be identified by accessing a database that includes an identity of the UE sending the request and one or more capabilities of the UE.

[0362] Thus, method 3900 may provide wireless communication. Note that method 3900 is just one implementation and that the operations of method 3900 may be rearranged or otherwise modified such that other implementations are possible.

[0363] 40 is a flowchart illustrating an example of a method 4000 for wireless communication in a base station in accordance with various aspects of the present disclosure. For clarity, the method 4000 is described below with reference to one or more aspects of the base station 105 described with reference to FIGS. 1-6 and 16-25. In some examples, the base station may execute one or more sets of code for controlling functional elements of the base station to perform functions described below. In some examples, the method 4000 may be performed by the base station transmitting system information in a unicast, narrow beam, broadcast, or broad beam manner.

[0364] In block 4005, the base station may broadcast information on a downlink channel. This information may indicate that master system information (e.g., MSIB) is to be transmitted in response to a master system information request (e.g., MSIB transmission request) received from a UE. In some examples, the downlink channel may include a synchronization signal. This information may be included in (or associated with) the synchronization signal. The operations in block 4005 may be performed using the SI transmission module 1620 described with reference to FIG. 20, 21, 24A, 24B, or 25, or the synchronization signal transmission management module 2105 described with reference to FIG. 21.

[0365] In block 4010, the base station may receive a master system information request (e.g., according to information broadcast on a downlink channel). In some cases, receiving the master system information request may include receiving in the request identification information of one or more capabilities of the UE transmitting the request. The operations in block 4010 may be performed using the SI transmission module 1620 described with reference to FIG. 20, FIG. 21, FIG. 24A, FIG. 24B, or FIG. 25, or the SI request processing module 2010 described with reference to FIG. 20 or FIG. 21.

[0366] In block 4015, the base station may transmit master system information in response to receiving the master system information request. In some cases, the master system information may include system information that enables the UE to perform initial access of the network using one or more of network identification information, base station identification information, cell selection configurations and access restrictions, or network access configurations. The operations in block 4015 may be performed using the SI transmission module 1620 described with reference to FIG. 20, FIG. 21, FIG. 24A, FIG. 24B, or FIG. 25, or the master SI transmission management module 2005 described with reference to FIG. 20 or FIG. 21.

[0367] The base station may receive a request for additional system information at block 4020. The operations at block 4020 may be performed using the SI transmission module 1620 described with respect to Figure 20, Figure 21, Figure 24A, Figure 24B, or Figure 25, or the SI request processing module 2010 described with respect to Figure 20 or Figure 21.

[0368] In block 4025, the base station may transmit the additional system information based at least in part on the request for the additional system information. In some cases, the additional system information may be specified based at least in part on one or more capabilities of the UE specified in the master system information request. The additional system information may also be specified based at least in part on information received in the request for the additional system information or in other manners (e.g., as described with respect to FIG. 38). The operations in block 4025 may be performed using the SI transmission module 1620 described with respect to FIG. 20, 21, 24A, 24B, or 25, or other SI transmission management module 2015 described with respect to FIG. 20 or 21.

[0369] In some embodiments of method 4000, transmitting the master system information may include transmitting an indication of one or more sets of additional system information that are available. In some embodiments of method 4000, receiving a request for the additional system information may include receiving multiple requests for the additional system information corresponding to multiple sets of additional system information to be transmitted. For example, method 4000 may include receiving a single OSIB transmission request indicating one or more elements of the additional system information that the UE desires to receive (e.g., a binary value in the OSIB transmission request may be set to true for each element of the additional system information that the UE desires to receive). In other examples, method 4000 may include receiving requests for several types of additional system information in different OSIB transmission requests.

[0370] Thus, method 4000 may provide wireless communication. Note that method 4000 is just one implementation and that the operations of method 4000 may be rearranged or otherwise modified such that other implementations are possible.

[0371] 41 is a flowchart illustrating an example of a method 4100 for wireless communication in a UE in accordance with various aspects of the present disclosure. For clarity, the method 4100 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-15 and 25. In some examples, the UE may execute one or more sets of code for controlling functional elements of the UE to perform functions described below.

[0372] In block 4105, the UE may receive a first signal (e.g., a synchronization signal, a paging message, or another type of transmission (e.g., an MSIB)). Upon receiving the first signal, the UE may communicate with the network using the first system information. The operations in block 4105 may be performed using the SI acquisition module 720 described with respect to FIG. 13, 14, 15, or 25, or the signal processing module 1305 described with respect to FIG. 13 or 14.

[0373] In block 4110, the UE may determine to request updated system information based at least in part on the first signal. The operations in block 4110 may be performed using the SI acquisition module 720 described with respect to Figure 13, 14, 15, or 25, or the signal processing module 1305 described with respect to Figure 13 or 14.

[0374] The UE may request updated system information based at least in part on the determination at block 4115. The operations at block 4115 may be performed using the SI acquisition module 720 described with respect to Figure 13, 14, 15, or 25, or the UE SI request module 1310 described with respect to Figure 13 or 14.

[0375] In some embodiments of method 4100, receiving the first signal may include receiving an indication that at least a portion of the first system information has changed. In some examples, the indication may include a modification flag. The modification flag may indicate, via a counter value or a Boolean variable (e.g., a binary value), that the corresponding portion of the system information has changed. In some examples, the indication may include one or more value tags, as described in more detail with respect to FIG. 6 or FIG. 43.

[0376] In some embodiments of method 4100, determining to request updated system information at block 4110 may include at least one of determining that the UE has moved to a zone using second system information that is different from the first system information, determining that the network has changed at least a portion of the first system information, or determining that the UE has moved more than a predetermined distance from a location where it previously obtained the first system information (e.g., from a location where the UE last obtained the first system information).

[0377] In some embodiments of method 4100, receiving the first signal at block 4105 may include receiving a zone identifier (e.g., an area code, BSIC, or another cell identifier). In some cases, the zone identifier may be received as part of the synchronization signal. In these embodiments, method 4100 may include using the zone identifier to determine that the UE has moved from the first zone to the second zone.

[0378] In some embodiments of method 4100, determining to request updated system information at block 4110 may include determining a distance between the current location of the UE and a location from which the UE previously (e.g., last) obtained the first system information, and determining that the determined distance exceeds a predetermined threshold. In some cases, the predetermined threshold may be received from a network. In some cases, a location signal identifying the location of the UE may also be received. The location signal may be received, for example, as part of receiving the first signal. The location signal may also be received in other manners, such as via GNSS (e.g., GPS, Galileo, GLONASS, or Beidou).

[0379] Thus, method 4100 may provide wireless communication. Note that method 4100 is just one implementation and that the operations of method 4100 may be rearranged or otherwise modified such that other implementations are possible.

[0380] 42 is a flowchart illustrating an example of a method 4200 for wireless communication in a UE, in accordance with various aspects of the present disclosure. For clarity, the method 4200 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-15 and 25. In some examples, the UE may execute one or more sets of code for controlling functional elements of the UE to perform functions described below.

[0381] In block 4205, the UE may receive a first signal (e.g., a synchronization signal, a paging message, or another type of transmission (e.g., an MSIB)). Upon receiving the first signal, the UE may communicate with the network using the first system information. The first signal may include an indication that at least a portion of the first system information has changed. The operations in block 4205 may be performed using the SI acquisition module 720 described with respect to FIG. 13, 14, 15, or 25, or the signal processing module 1305 described with respect to FIG. 13 or 14.

[0382] In block 4210, the UE may receive one or more modification flags, each indicating by a counter value or a Boolean variable (e.g., a binary value) that the corresponding portion of the first system information has changed. In some examples, the corresponding portion of the first system information may include a portion of master system information, such as an MSIB or an element of the MSIB. In other examples, the corresponding portion of the first system information may include additional non-master system information, such as an OSIB or an element of the OSIB. The master system information may include one or more of: identification information of the network, identification information of base stations in the network, cell selection configuration and access restrictions, or network access configuration information. The master system information may additionally or alternatively include, for example, one or more other elements of the master system information described with respect to FIG. 3A. The additional non-master system information may include one or more elements of other system information described with respect to FIG. 4 or FIG. 6. In some embodiments, the modification flag received in block 4210 may be received along with (or as part of) the first signal received in block 4205. The operations in block 4210 may be performed using the SI acquisition module 720 described with respect to FIG. 13, FIG. 14, FIG. 15, or FIG. 25, the signal processing module 1305 described with respect to FIG. 13 or FIG. 14, or the modified flag or value tag processing module 1405 described with respect to FIG. 14.

[0383] In block 4215, the UE may determine to request updated system information based at least in part on the first signal or the modification flag (e.g., when the modification flag is set to true). The operations in block 4215 may be performed using the SI acquisition module 720 described with reference to FIG. 13, 14, 15, or 25, the signal processing module 1305 described with reference to FIG. 13 or 14, or the modification flag or value tag processing module 1405 described with reference to FIG. 14.

[0384] The UE may request updated system information (e.g., an updated MSIB or OSIB) based at least in part on the determination at block 4220. The operations at block 4220 may be performed using the SI acquisition module 720 described with respect to FIG. 13, FIG. 14, FIG. 15, or FIG. 25, or the UE SI request module 1310 described with respect to FIG. 13 or FIG. 14.

[0385] Thus, method 4200 may provide wireless communication. Note that method 4200 is just one implementation and that the operations of method 4200 may be rearranged or otherwise modified such that other implementations are possible.

[0386] 43 is a flowchart illustrating an example of a method 4300 for wireless communication in a UE, in accordance with various aspects of the present disclosure. For clarity, the method 4300 is described below with reference to one or more aspects of the UE 115 described with reference to FIGS. 1-15 and 25. In some examples, the UE may execute one or more sets of code for controlling functional elements of the UE to perform functions described below.

[0387] In block 4305, the UE may receive a first signal (e.g., a synchronization signal, a paging message, or another type of transmission (e.g., an MSIB)). Upon receiving the first signal, the UE may communicate with the network using the first system information. The first signal may include an indication that at least a portion of the first system information has changed. The operations in block 4305 may be performed using the SI acquisition module 720 described with respect to FIG. 13, 14, 15, or 25, or the signal processing module 1305 described with respect to FIG. 13 or 14.

[0388] At block 4310, the UE may receive one or more value tags corresponding to at least a portion (or various portions) of the changed first system information. In some examples, the one or more value tags may correspond to one or more portions of the master system information, one or more portions of additional non-master system information, or a combination thereof. The master system information may include one or more of: identification information of the network, identification information of base stations in the network, cell selection configurations and access restrictions, or network access configuration information. The master system information may additionally or alternatively include one or more other elements of the master system information described with respect to, for example, FIG. 3A. The additional non-master system information may include one or more elements of other system information described with respect to FIG. 4 or FIG. 6. In some embodiments, the one or more value tags received at block 4310 may be received along with (or as part of) the first signal received at block 4305. The operations in block 4310 may be performed using the SI acquisition module 720 described with respect to FIG. 13, FIG. 14, FIG. 15, or FIG. 25, the signal processing module 1305 described with respect to FIG. 13 or FIG. 14, or the modified flag or value tag processing module 1405 described with respect to FIG. 14.

[0389] In block 4315, the UE may determine to request updated system information based at least in part on the first signal or one or more value tags. In some cases, determining to request updated system information may include comparing a received value tag (e.g., a received value tag associated with an element of non-master system information included in the OSIB) with a previously received value tag (e.g., a previously received value tag for the element of non-master system information) and determining to request updated system information based at least in part on the comparison (e.g., determining to request updated system information when the value tags do not match). When a received value tag corresponds to an element of system information that the UE is not monitoring, the UE may not compare the value tag with previously received value tags or may not request the element of system information. The operations in block 4315 may be performed using the SI acquisition module 720 described with respect to FIG. 13, FIG. 14, FIG. 15, or FIG. 25, the signal processing module 1305 described with respect to F...

Claims

1. 1. A method for wireless communication in a user equipment (UE), comprising: receiving a first signal, the first signal comprising a system information block including a first indication of whether system information should be requested by the UE and a second indication of at least one of channel information, frequency information, or timing information for transmitting the request for the system information by the UE, the first indication being based at least in part on whether the system information should be transmitted in a broadcast mode or an on-demand mode; identifying one or more functions for which system information should be obtained; transmitting the request for system information in accordance with the first instruction; receiving the system information in accordance with the first instruction and the request; The method, wherein the received system information includes system information for the identified one or more features.

2. The method of claim 1 , wherein the on-demand mode comprises an on-demand mode in which the system information is not broadcast.

3. The method of claim 1 , further comprising: establishing a connection between the UE and a base station according to the received system information.

4. The method of claim 1 , wherein the one or more functions are associated with a service, the service comprising a Public Warning System (PWS) service.

5. receiving the first signal The method of claim 1 , further comprising receiving information indicating a predetermined channel on which system information is to be transmitted via a second broadcast signal via broadcast or broad beam operation.

6. receiving the system information, receiving the system information via a second signal in accordance with the first instruction, the second signal being transmitted via broadcast or broad beam operation; receiving said system information as part of broad beam or narrow beam operation; or The method of claim 1 , further comprising one or more of receiving the system information as part of a broadcast or unicast operation.

7. receiving the first signal 10. The method of claim 1, further comprising receiving the first signal as part of broad beam or broadcast operation in a massive multiple input / multiple output (MIMO) network.

8. 2. The method of claim 1, further comprising identifying one or more services for which system information is to be obtained, wherein receiving the system information further comprises receiving system information for the identified one or more services in accordance with the first instruction.

9. receiving the system information, transmitting a request for the system information for the one or more services; and receiving the system information for the one or more services in response to the request.

10. receiving the system information, sending a separate request for system information for each of the one or more services, each request being for system information of a different service; and receiving system information for the one or more services in response to each request.

11. receiving the first signal 10. The method of claim 8, further comprising receiving a third indication that system information for the one or more services is available or should be broadcast at one or more predetermined times and on one or more predetermined channels.

12. receiving the system information, 9. The method of claim 8, further comprising receiving the system information for the one or more services, the system information including information identifying the one or more services for which the system information is valid.

13. receiving the system information, receiving the system information for one of the one or more services; determining whether additional system information for one of the one or more services is needed; and requesting additional system information for the one of the one or more services based at least in part on the determination.

14. receiving the system information, receiving the system information for the one or more services, the system information including information identifying a validity period; and reacquiring the system information for the one or more services when the validity period expires.

15. 1. A method for wireless communication in a base station, comprising: transmitting a first signal, the first signal including a first indication of whether system information should be requested by a user equipment (UE) and a second indication of at least one of channel information, frequency information, or timing information for transmitting the request for the system information by the UE, the first indication being based at least in part on whether the system information should be transmitted in a broadcast mode or an on-demand mode; receiving the request for the system information in accordance with the instructions; transmitting the system information in accordance with the first indication and the request, wherein the system information is associated with features available to the UE and separate transmissions are used to transmit the system information for different features and different configurations of features.

16. The method of claim 15 , wherein the on-demand mode comprises an on-demand mode in which the system information is not broadcast.

17. The method of claim 15, further comprising: establishing a connection between a base station and the UE according to the received system information.

18. the step of transmitting the system information 16. The method of claim 15, further comprising transmitting the system information via a second signal in accordance with the instructions, the second signal being transmitted via broadcast or broad beam operation.

19. the step of transmitting the first signal comprises:

16. The method of claim 15, further comprising transmitting, in the first signal, information indicating a predetermined channel over which the system information should be transmitted via broadcast or broad beam operation.

20. the step of transmitting the system information The method of claim 15, further comprising transmitting the system information according to the instructions and transmission mode.

21. changing the transmission mode to be a broadcast or broad beam mode targeted to cell edges and with fixed periodic scheduling; changing the transmission mode to be a broadcast or broad beam mode targeted at a cell edge and with on-demand periodic scheduling triggered by the request for the system information according to the first indication; changing the transmission mode to be a broadcast or broad beam mode with on-demand, occasional scheduling triggered by the request for the system information in accordance with the first indication; changing the transmission mode to be a unicast or narrow beam mode with on-demand, occasional scheduling triggered by the request for the system information in accordance with the first indication; or 21. The method of claim 20, further comprising one or more of the steps of varying the transmission mode based at least in part on network load or congestion conditions.

22. 16. The method of claim 15, transmitting system information using broad beam or narrow beam operation according to the first instruction and transmission mode.

23. transmitting the first signal in a massive multiple-input / multiple-output (MIMO) network using broad beam operation; transmitting the first signal in a non-massive multiple-input / multiple-output (MIMO) network using a broadcast operation; or 16. The method of claim 15, further comprising one of transmitting the system information in accordance with the first indication and transmission mode using a broadcast or unicast operation.

24. the step of transmitting the system information 16. The method of claim 15, further comprising transmitting system information associated with available services to the UE in accordance with the first indication, wherein separate transmissions are used to transmit the system information for different services and different configurations of services.

25. receiving a request for the system information for one or more services in accordance with the instructions; and transmitting the system information for the one or more services in response to the request.

26. the step of transmitting the first signal comprises:

16. The method of claim 15, further comprising transmitting, in the first signal, a third indication that the system information for one or more services is available to be requested or should be broadcast at one or more predetermined times and on one or more predetermined channels.

27. the step of transmitting the system information The method of claim 15, further comprising transmitting, in the system information, information indicating one or more services for which the system information is valid.

28. 16. The method of claim 15, further comprising receiving one or more requests for system information for one or more services in accordance with the first indication without including in the first signal a third indication of which service system information is available.

29. 1. An apparatus for wireless communication in a user equipment (UE), comprising: a processor; memory in electronic communication with said processor; instructions stored in the memory, the instructions configured by the processor to: receiving a first signal, the first signal including a first indication of whether system information should be requested by the UE and a second indication of at least one of channel information, frequency information, or timing information for transmitting the request for the system information by the UE, the first indication being based at least in part on whether the system information should be transmitted in a broadcast mode or an on-demand mode; identifying one or more functions for which system information should be obtained; transmitting the request for the system information in accordance with the first instruction; receiving the system information in accordance with the first instruction and the request, the received system information including system information for the identified one or more functions; An apparatus operable to perform the steps of:

30. 1. An apparatus for wireless communication at a base station, comprising: a processor; memory in electronic communication with said processor; instructions stored in the memory, the instructions configured by the processor to: transmitting a first signal, the first signal including a first indication of whether system information should be requested by a user equipment (UE) and a second indication of at least one of channel information, frequency information, or timing information for transmitting the request for the system information by the UE, the first indication being based at least in part on whether the system information should be transmitted in a broadcast mode or an on-demand mode; receiving the request for the system information in accordance with the instructions; transmitting the system information in accordance with the first indication and the request, the system information being associated with features available to the UE, and separate transmissions being used to transmit the system information for different features and different configurations of features; An apparatus operable to perform the steps of:

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