Method for efficient physical random access channel (RACH) opportunity (RO) determination in cell discontinuous reception (DRX) mode

Abstract

The present application relates to an improved method of operating a user equipment (UE), the improved method comprising: transmitting a first capability indication to a base station (e.g., gNB or gNodeB), where the first capability indication indicates that the UE has network energy saving (NES) capability; receiving a first physical random access channel (RACH) occasion (RO) configuration and a first discontinuous reception (DRX) mode configuration, wherein the first DRX mode configuration specifies a DRX cycle used by the base station; determining, by the UE, a first set of valid ROs for transmitting a RACH message to a base station, wherein determining the first set of valid ROs further includes determining an active time at which the base station will be in a first DRX mode during the first set of valid ROs; and transmitting a first RACH message to the base station during a first valid RO in the determined first set of valid ROs.

Description

Technical Field

[0001] The present application relates to wireless devices and wireless networks, including user equipment, terminals, circuits, computer-readable media, and methods for performing effective physical random access channel (RACH) opportunity (RO) determination in a cell discontinuous reception (DRX) mode. Background Art

[0002] The use of wireless communication systems is growing rapidly. In recent years, wireless devices (such as smart phones and tablet computers) have become increasingly complex and sophisticated. In addition to supporting phone calls, many mobile devices now also provide access to the Internet, email, text messaging and navigation using the Global Positioning System (GPS), and are capable of operating complex and sophisticated applications that utilize these functionalities. Additionally, there are many different wireless communication technologies and wireless communication standards. Some examples of wireless communication standards include GSM, UMTS (e.g., associated with WCDMA or TD-SCDMA air interfaces), Long Term Evolution (LTE), Advanced LTE (LTE-A), HSPA, 3GPP2 CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), IEEE 802.11 (WLAN or Wi-Fi), and Bluetooth. TM etc.

[0003] The introduction of an ever-increasing number of features and functionalities in wireless communication devices has also created a continuous demand for improved wireless communications and improved wireless communication devices. In order to increase coverage and better serve the increasing demand and scope of intended uses of wireless communications, in addition to the communication standards mentioned above, there are also wireless communication technologies under development, including the fifth generation (5G) standard and new radio (NR) communication technology and above. Therefore, there is a need for improvements in the field that support such development and design.

[0004] In the 3rd Generation Partnership Project (3GPP) standards development, conservation of energy and processing resources is almost always an important design consideration. Recently, research has been proposed in 3GPP to investigate whether network (i.e., cell tower / base station) discontinuous transmission (DTX) and / or discontinuous reception (DRX) modes can be used to effectively achieve greater network energy savings (NES). However, determining whether (and when) a base station (also referred to herein as a "gNB" or "gNodeB") can stop listening to the physical random access channel (i.e., "RACH" or "PRACH") and transmitting a random access response (RAR) message is crucial to achieving such network energy savings gains. Therefore, improvements are desired that can intelligently define new RACH Occasion (RO) mapping criteria (as well as several RAR reception schemes) to achieve maximum network energy savings gains and strike an appropriate balance between network energy savings gains and UE network access latency. Summary of the Invention

[0005] According to one or more embodiments, a method of operating a user equipment (UE) is disclosed herein, the method comprising: sending a first capability indication from the UE to a base station (e.g., a gNB or gNodeB), wherein the first capability indication indicates that the UE has network energy saving (NES) capability; receiving a first physical random access channel (RACH) opportunity (RO) configuration and a first discontinuous reception (DRX) mode configuration from the base station at the UE, wherein the first DRX mode configuration specifies a DRX cycle used by the base station; determining, by the UE, a first set of valid ROs for sending a RACH message to the base station, wherein determining the first set of valid ROs further comprises determining an active time during which the base station will be in the first DRX mode during the first set of valid ROs; and sending a first RACH message (e.g., a random access preamble (Msg1) message) from the UE to the base station during a first valid RO in the determined first set of valid ROs.

[0006] According to some aspects, when sending a RACH message to the base station, the UE may only be in an RRC_CONNECTED state. According to other aspects, the first capability indication may be used to indicate that the UE is capable of applying one or more valid RO criteria when determining the first set of valid ROs. According to still other aspects, the first valid RO is associated with a first synchronization signal / physical broadcast channel (SS / PBCH) block index.

[0007] According to other aspects, the method may also include: determining, by the UE, a second valid RO from the first set of determined valid ROs for sending a second RACH message to the base station; and sending the second RACH message from the UE to the base station during the determined second valid RO (for example, wherein the second valid RO is associated with a second SS / PBCH block index, which is different from the SS / PBCH block index associated with the first SS / PBCH block index).

[0008] According to further aspects, each SS / PBCH block in the set of SS / PBCH blocks is associated with at least one RO in the first set of valid ROs.

[0009] According to yet other aspects, the base station is further configured to use a first discontinuous transmission (DTX) mode (e.g., wherein the base station is configured not to transmit to the UE outside of an active time of a DTX cycle configured in the first DTX mode). According to some such aspects, the method may further include: receiving, at the UE, a random access response (RAR) message sent from the base station in response to the first RACH message (e.g., wherein the ra-ResponseWindow is configured to be paused outside of the active time of the DTX cycle). According to yet other aspects, the method may further include: determining the first valid RO in the first set of determined valid ROs (e.g., determining the position of the first valid RO in time and / or frequency), wherein determining the first valid RO further includes determining that the last symbol of the first valid RO is at least a threshold number N symbols before the last symbol of the active time of the DRX cycle in which the first valid RO is located.

[0010] The various methods and techniques outlined in this section may also be performed by a UE device comprising: a receiver; a transmitter; and a processor configured to perform any of the various methods and techniques outlined herein. The various methods and techniques outlined in this section may also be stored as instructions on a non-transitory computer-readable medium, where these instructions, when executed, cause the various methods and techniques outlined herein to be performed.

[0011] This summary is intended to provide a brief overview of some of the subject matter described in this document. Therefore, it should be understood that the aforementioned features are merely examples and should not be construed as narrowing the scope or spirit of the subject matter described herein in any way. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following detailed description, accompanying drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] A better understanding of the present subject matter may be gained when the following detailed description of various aspects is considered in conjunction with the following drawings:

[0013] Figure 1

[0014] An example wireless communication system according to some aspects is illustrated.

[0014] Figure 2 An example block diagram of a UE is illustrated in accordance with some aspects.

[0015] Figure 3 Illustrated is an example block diagram of a base station (BS) in accordance with some aspects.

[0016] Figure 4 An example block diagram of wireless communication circuitry is illustrated in accordance with some aspects.

[0017] Figure 5Various diagrams illustrating examples of a mismatch between a cell DRX cycle active time and a valid RO within a PRACH associated period are illustrated in accordance with some aspects.

[0018] Figures 6A to 6B Various diagrams illustrating exemplary solutions to the mismatch problem between cell DRX cycle active time and valid RO within a PRACH associated period are illustrated in accordance with some aspects.

[0019] Figure 7 is a flow chart detailing a method for performing effective RO determination when a cell operates in DRX mode according to some aspects.

[0020] While the features described herein are susceptible to various modifications and alternative forms, specific aspects thereof are shown by way of example in the drawings and described in detail herein. It should be understood, however, that the drawings and detailed description thereof are not intended to be limiting to the particular forms disclosed, but, on the contrary, are intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter as defined by the appended claims. DETAILED DESCRIPTION

[0021] The present application relates to improved methods for effective Physical Random Access Channel (PRACH) opportunity (RO) determination for cellular networks operating in discontinuous transmission (DTX) and / or discontinuous reception (DRX) mode in order to achieve greater network energy savings (NES).

[0022] The following is a glossary of additional terms that may be used in this disclosure:

[0023] Memory medium – Any of various types of non-transitory memory devices or storage devices. The term “memory medium” is intended to include installation media (e.g., CD-ROM, floppy disk, or tape device; computer system memory or random access memory such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM), non-volatile memory such as Flash, magnetic media (e.g., hard drive or optical storage device; registers or other similar types of memory elements). Memory media may also include other types of non-transitory memory or a combination thereof. Furthermore, the memory medium may be located in a first computer system executing a program, or may be located in a different second computer system connected to the first computer system via a network (such as the Internet). In the latter example, the second computer system may provide program instructions to the first computer for execution. The term “memory medium” may include two or more memory media that may reside in different locations (e.g., in different computer systems connected via a network). The memory medium may store program instructions (e.g., represented as a computer program) that may be executed by one or more processors.

[0024] Carrier Medium—memory media as described above, as well as physical transmission media such as a bus, network, and / or other physical transmission media that convey signals such as electrical, electromagnetic, or digital signals.

[0025] Programmable hardware elements - include various hardware devices that include multiple programmable function blocks connected via programmable interconnects. Examples include FPGAs (field programmable gate arrays), PLDs (programmable logic devices), FPOAs (field programmable object arrays), and CPLDs (complex PLDs). Programmable function blocks can range from fine-grained (combinatorial logic or lookup tables) to coarse-grained (arithmetic logic units or processor cores). Programmable hardware elements may also be referred to as "configurable logic units."

[0026] User Equipment (UE) (also called "user device," "UE device," or "terminal") - any of various types of computer systems or devices that are mobile or portable and that perform wireless communication. Examples of UE devices include mobile phones or smartphones (e.g., iPhones). TM , based on Android TM phones), portable gaming devices (e.g., Nintendo Switch TM 、Nintendo DS TM PlayStation Vita TM PlayStation Portable TM 、Gameboy Advance TM , iPhone TM ), laptops, wearable devices (e.g., smart watches, smart glasses), PDAs, portable internet devices, music players, data storage devices, other handheld devices, in-vehicle infotainment (IVI), in-car entertainment (ICE) devices, instrument clusters, heads-up display (HUD) devices, on-board diagnostic (OBD) devices, dashboard mobile equipment (DME), mobile data terminals (MDT), electronic engine management systems (EEMS), electronic / engine control units (ECUs), electronic / engine control modules (ECMs), embedded systems, microcontrollers, control modules, engine management systems (EMS), connected or “smart” appliances, machine type communication (MTC) devices, machine-to-machine (M2M) and Internet of Things (IoT) devices, etc. In general, the term “UE” or “UE device” or “terminal” or “user equipment” may be broadly defined to encompass any electronic, computing and / or telecommunication device (or combination of devices) that is easily transportable by a user (or vehicle) and capable of wireless communication.

[0027] Wireless Device—Any of various types of computer systems or devices that perform wireless communications. A wireless device may be portable (or mobile), or may be stationary or fixed in place. A UE is an example of a wireless device.

[0028] Communication Device – Any of various types of computer systems or devices that perform communication, where the communication can be wired or wireless. A communication device can be portable (or mobile), or it can be stationary or fixed in place. A wireless device is one example of a communication device. A UE is another example of a communication device.

[0029] Base Station – The terms “base station,” “wireless base station,” or “wireless station” have the full scope of their ordinary meaning and include at least a wireless communication station installed at a fixed location and used to communicate as part of a wireless telephone system or radio system. For example, if a base station is implemented in the context of LTE, it may alternatively be referred to as an “eNodeB” or “eNB.” If a base station is implemented in the context of 5G NR, it may alternatively be referred to as a “gNodeB” or “gNB.” Although certain aspects are described in the context of LTE or 5G NR, references to “eNB,” “gNB,” “nodeB,” “base station,” and “NB” may also refer to one or more wireless nodes that serve a cell to provide wireless connectivity between user equipment and a generally wider network, and the concepts discussed are not limited to any particular wireless technology. Although certain aspects are described in the context of LTE or 5G NR, references to “eNB,” “gNB,” “nodeB,” “base station,” and “NB” are not intended to limit the concepts discussed herein to any particular wireless technology, and the concepts discussed are applicable to any wireless system.

[0030] Node—The term “node” or “wireless node” as used herein may refer to one or more devices associated with a cell that provides wireless connectivity between user equipment and a typically wired network.

[0031] Processing element (or processor) – refers to any of the various elements or combinations of elements that are capable of performing functions in a device, such as user equipment or a cellular network device. A processing element may include, for example, a processor and associated memory, portions or circuits of individual processor cores, an entire processor core, a separate processor, an array of processors, circuits such as an application-specific integrated circuit (ASIC), programmable hardware elements such as a field-programmable gate array (FPGA), and various combinations thereof.

[0032] Channel - a medium used to transport information from a transmitter (sender) to a receiver. It should be noted that since the characteristics of the term "channel" may vary according to different wireless protocols, the term "channel" as used herein may be considered to be used in a manner that is consistent with the standard of the type of device to which the term is used. In some standards, the channel width may be variable (e.g., depending on device capabilities and frequency band conditions, etc.). For example, LTE may support scalable channel bandwidths of 1.4MHz to 20MHz. A WLAN channel may be 22MHz wide, while a Bluetooth channel may be 1Mhz wide. Other protocols and standards may include different definitions of channels. In addition, some standards may define and use multiple types of channels (e.g., different channels for uplink or downlink and / or different channels for different purposes (such as data and control information, etc.)).

[0033] Frequency band - The term "frequency band" has the full breadth of its ordinary meaning and includes at least a segment of the spectrum (eg, radio frequency spectrum) in which channels are used or set aside for the same purpose.

[0034] Configured to - Various components may be described as being "configured to" perform one or more tasks. In such contexts, "configured to" is a broad statement that generally means "having a structure" to perform one or more tasks during operation. Thus, a component can be configured to perform a task even when the component is not currently performing the task (e.g., a set of electrical conductors can be configured to electrically connect a module to another module even when the two modules are not connected). In some contexts, "configured to" can be a broad statement that generally means "having a structure" to carry out one or more tasks during operation. Thus, a component can be configured to perform a task even when the component is not currently turned on. Generally, the circuitry that forms the structure corresponding to "configured to" may include hardware circuitry.

[0035] For ease of description, various components may be described as performing one or more tasks. Such descriptions should be interpreted as including the phrase "configured to." Representing a component as being configured to perform one or more tasks expressly intends that the component not be interpreted under 35 U.S.C. §112(f).

[0036] Example Wireless Communication System

[0037] Now go to Figure 1 , illustrates a simplified example of a wireless communication system according to some aspects. Note that, Figure 1 The systems are merely non-limiting examples of possible systems, and features of the present disclosure may be implemented in any of a variety of systems as desired.

[0038] As shown, the example wireless communication system includes a base station 102A that communicates with one or more user devices 106A, 106B to 106Z via a transmission medium. Each of the user devices may be referred to herein as a "user equipment" (UE). Accordingly, user device 106 is referred to as a UE or UE device.

[0039] The base station (BS) 102A may be a base transceiver station (BTS) or a cell site (eg, a "cellular base station") and may include hardware that enables wireless communications with the UEs 106A-106Z.

[0040] The communication area (or coverage area) of a base station may be referred to as a "cell". The base station 102A and the UE 106 may be configured to communicate over a transmission medium using any of a variety of radio access technologies (RATs), also known as wireless communication technologies or telecommunication standards, such as GSM, UMTS (associated with, for example, WCDMA or TD-SCDMA air interfaces), LTE, LTE-A, 5G NR, HSPA, 3GPP2 CDMA2000. Note that if the base station 102A is implemented in the context of LTE, the base station may alternatively be referred to as an 'eNodeB' or an 'eNB'. Note that if the base station 102A is implemented in the context of 5G NR, the base station may alternatively be referred to as a 'gNodeB' or a 'gNB'.

[0041] In some aspects, UE 106 may be an IoT UE that may include a network access layer designed for low-power IoT applications that utilize short-term UE connections. The IoT UE may utilize technologies such as M2M or MTC to exchange data with an MTC server or device via a public land mobile network (PLMN), proximity service (ProSe), or device-to-device (D2D) communication, a sensor network, or an IoT network. M2M or MTC data exchange may be machine-initiated data exchange. An IoT network describes interconnected IoT UEs that may include uniquely identifiable embedded computing devices (within the Internet infrastructure) with short-term connections. As an example, vehicle-to-everything (V2X) may utilize ProSe features using an SL interface to communicate directly between devices. The IoT UE may also execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate connectivity to the IoT network.

[0042] As shown, UEs 106 (such as UE 106A and UE 106B) may directly exchange communication data via a SL interface 108. The SL interface 108 may be a PC5 interface that includes one or more physical channels, including but not limited to a physical sidelink shared channel (PSSCH), a physical sidelink control channel (PSCCH), a physical sidelink broadcast channel (PSBCH), and a physical sidelink feedback channel (PSFCH).

[0043] In a V2X scenario, one or more of base stations 102 may be a roadside unit (RSU) or function as an RSU. The term RSU may refer to any transportation infrastructure entity used for V2X communications. An RSU may be implemented in or by a suitable wireless node or stationary (or relatively stationary) UE. An RSU implemented in or by a UE may be referred to as a "UE-type RSU," an RSU implemented in or by an eNB may be referred to as an "eNB-type RSU," an RSU implemented in or by a gNB may be referred to as a "gNB-type RSU," and so on. In one example, an RSU is a computing device coupled to radio frequency circuitry located on the roadside that provides connectivity support to passing vehicle UEs (vUEs). The RSU may also include internal data storage circuitry for storing intersection map geometry, traffic statistics, media, and applications / software for sensing and controlling ongoing vehicular and pedestrian traffic. The RSU may operate on the 5.9 GHz Intelligent Transportation System (ITS) band to provide extremely low latency communications required for high-speed events, such as collision avoidance and traffic warnings. Additionally or alternatively, the RSU may operate on the cellular V2X band to provide the aforementioned low latency communications as well as other cellular communication services. Additionally or alternatively, the RSU may operate as a Wi-Fi hotspot (2.4 GHz band) and / or provide connectivity with one or more cellular networks to provide uplink and downlink communications. Some or all of the RF circuits of the computing device and the RSU may be encapsulated in a weather-resistant enclosure suitable for outdoor installation, and may include a network interface controller to provide a wired connection (e.g., Ethernet) to a traffic signal controller and / or backhaul network.

[0044] As shown, base station 102A may also be configured to communicate with network 100 (e.g., a cellular service provider's core network, a telecommunications network such as the Public Switched Telephone Network (PSTN) and / or the Internet, among other possibilities). Thus, base station 102A may facilitate communications between user devices and / or between user devices and network 100. Specifically, cellular base station 102A may provide UE 106 with various telecommunications capabilities, such as voice, SMS, and / or data services.

[0045] Base station 102A and other similar base stations (such as base stations 102B to 102N) operating according to the same or different cellular communication standards can thus be provided as a network of cells that can provide continuous or nearly continuous overlapping service to UEs 106A to 106Z and similar devices over a geographic area via one or more cellular communication standards.

[0046] Thus, although base station 102A may function as Figure 1 The illustrated "serving cell" of UEs 106A to 106Z is shown, but each UE 106 may also be able to receive signals from (and possibly be within communication range of) one or more other cells (which may be provided by base stations 102B to 102Z and / or any other base stations), which may be referred to as "neighboring cells." Such cells may also be able to facilitate communications between user devices and / or between user devices and network 100. Such cells may include "macro" cells, "micro" cells, "pico" cells, and / or cells of any other variety of granularity of service area size. For example, in Figure 1 The base stations 102A and 102B illustrated in FIG may be macro cells, while the base station 102Z may be a micro cell. Other configurations are also possible.

[0047] In some aspects, the base station 102A may be a next generation base station (e.g., a 5G New Radio (5GNR) base station or "gNB"). In some aspects, the gNB may be connected to a legacy evolved packet core (EPC) network and / or to an NR core (NRC) / 5G core (5GC) network. In addition, a gNB cell may include one or more transition and reception points (TRPs). In addition, a UE capable of operating in accordance with 5GNR may be connected to one or more TRPs within one or more gNBs. For example, the base station 102A and one or more other base stations 102 may support joint transmissions such that the UE 106 may be able to receive transmissions from multiple base stations (and / or multiple TRPs provided by the same base station). For example, as Figure 1 As illustrated, base station 102A and base station 102C are both shown serving UE 106A.

[0048] It is noted that the UE 106 may be capable of communicating using multiple wireless communication standards. For example, in addition to at least one of the cellular communication protocols discussed in the above definitions, the UE 106 may also be configured to communicate using wireless networking (e.g., Wi-Fi) and / or peer-to-peer wireless communication protocols (e.g., Bluetooth and Wi-Fi peer-to-peer, etc.). If desired, the UE 106 may additionally or alternatively be configured to communicate using one or more global navigation satellite systems (GNSS) (e.g., GPS or GLONASS), one or more mobile television broadcast standards (e.g., ATSC-M / H), and / or any other wireless communication protocols. Other combinations of wireless communication standards (including more than two wireless communication standards) are also possible.

[0049] In one or more embodiments, the UE 106 may be a device with cellular communication capabilities, such as a mobile phone, handheld device, computer, laptop, tablet, smart watch or other wearable device, or virtually any type of wireless device.

[0050] The UE 106 may include a processor (processing element) configured to execute program instructions stored in a memory. The UE 106 may perform any of the method aspects described herein by executing such stored instructions. Alternatively or in addition, the UE 106 may include a programmable hardware element, such as an FPGA (field programmable gate array), an integrated circuit, and / or any of various other possible hardware components configured to perform (e.g., individually or in combination) any of the method aspects described herein or any portion of any of the method aspects described herein.

[0051] The UE 106 may include one or more antennas for communicating using one or more wireless communication protocols or technologies. In some aspects, the UE 106 may be configured to communicate using, for example, NR or LTE using at least some shared radio components. As an additional possibility, the UE 106 may be configured to communicate using CDMA2000 (1xRTT / 1xEV-DO / HRPD / eHRPD) or LTE using a single shared radio component and / or GSM or LTE using a single shared radio component. The shared radio component may be coupled to a single antenna, or may be coupled to multiple antennas (e.g., for a multiple-input, multiple-output (MIMO) configuration) for performing wireless communications. Generally speaking, the radio component may include any combination of a baseband processor, analog RF signal processing circuitry (e.g., including filters, mixers, oscillators, amplifiers, etc.), or digital processing circuitry (e.g., for digital modulation and other digital processing). Similarly, the radio component may implement one or more receive chains and transmit chains using the aforementioned hardware. For example, UE 106 may share one or more portions of a receive chain and / or a transmit chain between multiple wireless communication technologies, such as those discussed above.

[0052] In some aspects, the UE 106 may include a separate transmit chain and / or receive chain (e.g., including separate antennas and other radio components) for each wireless communication protocol with which it is configured to communicate. As another possibility, the UE 106 may include one or more radio components shared between multiple wireless communication protocols, and one or more radio components used uniquely by a single wireless communication protocol. For example, the UE 106 may include a shared radio component for communicating using either LTE or 5G NR (or either LTE or 1xRTT, or either LTE or GSM, among other possibilities), and separate radio components for communicating using each of Wi-Fi and Bluetooth. Other configurations are also possible.

[0053] In some aspects, a downlink resource grid may be used for downlink transmissions from any of the base stations 102 to the UE 106, while uplink transmissions may utilize similar techniques. The grid may be a time-frequency grid, referred to as a resource grid or a time-frequency resource grid, which is the physical resource in the downlink in each time slot. For orthogonal frequency division multiplexing (OFDM) systems, such a time-frequency plane representation is conventional practice, which makes radio resource selection intuitive. Each column and each row of the resource grid corresponds to an OFDM symbol and an OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to a time slot in the radio frame. The smallest time-frequency unit in the resource grid is represented as a resource element. Each resource grid may include multiple resource blocks, which describe the mapping of specific physical channels to resource elements. Each resource block includes a collection of resource elements. Such resource blocks are used to transport several different physical downlink channels.

[0054] The physical downlink shared channel (PDSCH) can carry user data and higher layer signaling to the UE 106. The physical downlink control channel (PDCCH) can carry information about, among other things, the transport format and resource allocation associated with the PDSCH channel. It can also inform the UE 106 of the transport format, resource allocation, and HARQ (Hybrid Automatic Repeat Request) information associated with the uplink shared channel. Typically, downlink scheduling (assignment of control and shared channel resource blocks to UEs 102 within a cell) can be performed at any of the base stations 102 based on channel quality information fed back from any of the UEs 106. Downlink resource allocation information can be transmitted on the PDCCH for (e.g., assigned to) each of the UEs.

[0055] PDCCH can use control channel elements (CCE) to convey control information. Before being mapped to resource elements, the PDCCH complex-valued symbols can first be organized into quadruples, which can then be arranged using a sub-block interleaver for rate matching. One or more of these CCEs can be used to send each PDCCH, where each CCE can correspond to four sets of nine physical resource elements, called resource element groups (REGs). Four quadrature phase shift keying (QPSK) symbols can be mapped to each REG. Depending on the size of the downlink control information (DCI) and the channel conditions, one or more CCEs can be used to send PDCCH. There may be four or more different PDCCH formats defined in LTE with different numbers of CCEs (e.g., aggregation levels, L=1, 2, 4, or 8).

[0056] Example Communication Device

[0057] Figure 2 An example simplified block diagram of a communication device 106 according to some aspects is illustrated. Note that Figure 2 The block diagram of the communication device is only one example of a possible communication device. According to various aspects, the communication device 106 can be, among other devices, a UE device or terminal, a mobile device or mobile station, a wireless device or wireless station, a desktop computer or computing device, a mobile computing device (e.g., a laptop, notebook or portable computing device), a tablet computer and / or a combination of devices. As shown, the communication device 106 may include a set of components 200 configured to perform core functions. For example, the set of components may be implemented as a system on a chip (SOC), which may include parts for various purposes. Alternatively, the set of components 200 may be implemented as individual components or groups of components for various purposes. The set of components 200 may be coupled (e.g., communicatively; directly or indirectly) to various other circuits of the communication device 106.

[0058] For example, the communication device 106 may include various types of memory (e.g., including NAND flash memory 210), input / output interfaces such as a connector I / F 220 (e.g., for connecting to a computer system; a docking station; a charging station; input devices such as a microphone, a camera, a keyboard; output devices such as a speaker; etc.), a display 260 that may be integrated with the communication device 106 or external to it, and wireless communication circuitry 230 (e.g., for LTE, LTE-A, NR, UMTS, GSM, CDMA2000, Bluetooth, Wi-Fi, NFC, GPS, etc.). In some aspects, the communication device 106 may include wired communication circuitry (not shown), such as a network interface card (e.g., for Ethernet connectivity).

[0059] Wireless communication circuitry 230 may be coupled (e.g., communicatively; directly or indirectly) to one or more antennas, such as antenna 235 as shown. Wireless communication circuitry 230 may include cellular communication circuitry and / or short- to medium-range wireless communication circuitry, and may include multiple receive chains and / or multiple transmit chains for receiving and / or transmitting multiple spatial streams, such as in a MIMO configuration.

[0060] In some aspects, as further described below, the cellular communication circuitry 230 may include one or more receive chains (including and / or coupled to (e.g., communicatively; directly or indirectly) dedicated processors and / or radios) for multiple radio access technologies (RATs) (e.g., a first receive chain for LTE and a second receive chain for 5G NR). Furthermore, in some aspects, the cellular communication circuitry 230 may include a single transmit chain that can switch between radios dedicated to specific RATs. For example, a first radio may be dedicated to a first RAT (e.g., LTE) and may communicate with a dedicated receive chain and a transmit chain shared with a second radio. A second radio may be dedicated to a second RAT (e.g., 5G NR) and may communicate with a dedicated receive chain and a shared transmit chain. In some aspects, the second RAT may operate at millimeter wave frequencies. Because millimeter wave systems operate at higher frequencies than typical frequencies in LTE systems, signals within the millimeter wave frequency range can be significantly attenuated by environmental factors. To help address this attenuation, millimeter wave systems typically utilize beamforming and include more antennas than LTE systems. These antennas can be organized into antenna arrays or panels consisting of individual antenna elements.These antenna arrays can be coupled to a radio link.

[0061] The communication device 106 may also include and / or be configured for use with one or more user interface elements.

[0062] The communication device 106 may also include one or more smart cards 245 , such as one or more Universal Integrated Circuit Cards (UICCs) 245 , that include Subscriber Identity Module (SIM) functionality.

[0063] As shown, SOC 200 may include a processor 202 that can execute program instructions for communication device 106 and a display circuit 204 that can perform graphics processing and provide display signals to display 260. Processor 202 may also be coupled to a memory management unit (MMU) 240 that can be configured to receive addresses from processor 202 and translate these addresses into locations in memory (e.g., memory 206, read-only memory (ROM) 250, NAND flash memory 210); and / or to other circuits or devices such as display circuit 204, wireless communication circuit 230, connector I / F 220, and / or display 260. MMU 240 may be configured to perform memory protection and page table translation or setup. In some aspects, MMU 240 may be included as part of processor 202.

[0064] As described above, the communication device 106 can be configured to communicate using wireless and / or wired communication circuits. As described herein, the communication device 106 may include hardware and software components for implementing any of the various features and techniques described herein. The processor 202 of the communication device 106 can be configured to implement a portion or all of the features described herein (e.g., by executing program instructions stored on a memory medium). Alternatively (or in addition), the processor 202 can be configured as a programmable hardware element, such as a field programmable gate array (FPGA) or as an application specific integrated circuit (ASIC). Alternatively (or in addition), in combination with one or more of the other components 200, 204, 206, 210, 220, 230, 240, 245, 250, 260, the processor 202 of the communication device 106 can be configured to implement a portion or all of the features described herein.

[0065] Furthermore, as described herein, processor 202 may include one or more processing elements. Thus, processor 202 may include one or more integrated circuits (ICs) configured to perform the functions of processor 202. Furthermore, each integrated circuit may include circuits (e.g., a first circuit and a second circuit, etc.) configured to perform the functions of processor 202.

[0066] Furthermore, as described herein, wireless communication circuitry 230 may include one or more processing elements. In other words, one or more processing elements may be included in wireless communication circuitry 230. Thus, wireless communication circuitry 230 may include one or more integrated circuits (ICs) configured to perform the functions of wireless communication circuitry 230. Furthermore, each integrated circuit may include circuitry (e.g., a first circuit and a second circuit, etc.) configured to perform the functions of wireless communication circuitry 230.

[0067] Example base station

[0068] Figure 3 An example block diagram of a base station 102 according to some aspects is illustrated. Note that Figure 3 The base stations of are non-limiting examples of possible base stations. As shown, base station 102 may include a processor 304 that may execute program instructions for base station 102. Processor 304 may also be coupled to a memory management unit (MMU) 340 that may be configured to receive addresses from processor 304 and translate those addresses into locations in memory (e.g., memory 360 and read-only memory (ROM) 350); or to other circuits or devices.

[0069] The base station 102 may include at least one network port 370. The network port 370 may be configured to couple to a telephone network and provide access to the telephone network as described above. Figure 1Multiple devices (such as UE device 106) of the telephone network described in.

[0070] The network port 370 (or an additional network port) may also or alternatively be configured to couple to a cellular network, such as a core network of a cellular service provider. The core network may provide mobility-related services and / or other services to a plurality of devices, such as the UE device 106. In some cases, the network port 370 may be coupled to a telephone network via the core network, and / or the core network may provide the telephone network (e.g., in addition to other UE devices served by the cellular service provider).

[0071] In some aspects, base station 102 can be a next-generation base station (e.g., a 5G New Radio (5GNR) base station or "gNB"). In such aspects, base station 102 can be connected to a legacy evolved packet core (EPC) network and / or to an NR core (NRC) / 5G core (5GC) network. Furthermore, base station 102 can be considered a 5G NR cell and can include one or more transition and reception points (TRPs). Furthermore, UEs capable of operating in accordance with 5G NR can be connected to one or more TRPs within one or more gNBs.

[0072] Base station 102 may include at least one antenna 334, and may include multiple antennas. At least one antenna 334 may be configured to operate as a wireless transceiver and may be further configured to communicate with UE device 106 via radio 330. Antenna 334 communicates with radio 330 via communication chain 332. Communication chain 332 may be a receive chain, a transmit chain, or both. Radio 330 may be configured to communicate via various wireless communication standards, including 5G NR, LTE, LTE-A, GSM, UMTS, CDMA2000, and Wi-Fi, among others.

[0073] The base station 102 may be configured to perform wireless communications using multiple wireless communication standards. In some instances, the base station 102 may include multiple radio components that enable the base station 102 to communicate according to multiple wireless communication technologies. For example, as one possibility, the base station 102 may include an LTE radio component for performing communications according to LTE and a 5G NR radio component for performing communications according to 5G NR. In this case, the base station 102 may be capable of operating as both an LTE base station and a 5G NR base station. When the base station 102 supports millimeter waves, the 5G NR radio component may be coupled to one or more millimeter wave antenna arrays or panels. As another possibility, the base station 102 may include a multimode radio component capable of performing communications according to any one of multiple wireless communication technologies (e.g., 5G NR and LTE, 5G NR and Wi-Fi, LTE and Wi-Fi, LTE and UMTS, LTE and CDMA2000, UMTS and GSM, etc.).

[0074] In addition, BS 102 may include hardware and software components for implementing or supporting the specific implementation of the features described herein. The processor 304 of the base station 102 may be configured to implement or support a specific implementation of part or all of the methods described herein (e.g., by executing program instructions stored on a memory medium). Alternatively, the processor 304 may be configured as a programmable hardware element, such as a field programmable gate array (FPGA), or as an application specific integrated circuit (ASIC) or a combination thereof. Alternatively (or in addition), in combination with one or more of the other components 330, 332, 334, 340, 350, 360, 370, the processor 304 of the BS 102 may be configured to implement or support implementing part or all of the features described herein.

[0075] Furthermore, as described herein, processor 304 may include one or more processing elements. Thus, processor 304 may include one or more integrated circuits (ICs) configured to perform the functions of processor 304. Furthermore, each integrated circuit may include circuits (e.g., a first circuit and a second circuit, etc.) configured to perform the functions of processor 304.

[0076] Furthermore, as described herein, radio 330 may include one or more processing elements. Thus, radio 330 may include one or more integrated circuits (ICs) configured to perform the functions of radio 330. Furthermore, each integrated circuit may include circuitry (e.g., a first circuit and a second circuit, etc.) configured to perform the functions of radio 330.

[0077] Example cellular communication circuit

[0078] Figure 4 An example simplified block diagram of a cellular communication circuit according to some aspects is illustrated. Note that Figure 4 The block diagram of the cellular communication circuitry is only one example of possible cellular communication circuitry; other circuitry, such as circuitry that includes or is coupled to sufficient antennas for different RATs to perform uplink activities using separate antennas, or circuitry that includes or is coupled to fewer antennas (e.g., that can be shared between multiple RATs), is also possible. According to some aspects, the cellular communication circuitry 230 can be included in a communication device, such as the communication device 106 described above. As described above, the communication device 106 can be, among other devices, a UE device, a mobile device or station, a wireless device or station, a desktop computer or computing device, a mobile computing device (e.g., a laptop, notebook, or portable computing device), a tablet, and / or a combination of devices.

[0079] The cellular communication circuitry 230 may be coupled (e.g., communicatively; directly or indirectly) to one or more antennas, such as antennas 235a, 235b, and 236 as shown. In some aspects, the cellular communication circuitry 230 may include dedicated receive chains (including and / or coupled (e.g., communicatively; directly or indirectly) to dedicated processors and / or radio components) for multiple RATs (e.g., a first receive chain for LTE and a second receive chain for 5G NR). For example, Figure 4 As shown, the cellular communication circuitry 230 may include a first modem 410 and a second modem 420. The first modem 410 may be configured to communicate according to a first RAT (e.g., such as LTE or LTE-A), and the second modem 420 may be configured to communicate according to a second RAT (e.g., such as 5G NR).

[0080] As shown, the first modem 410 may include one or more processors 412 and a memory 416 in communication with the processor 412. The modem 410 may communicate with a radio frequency (RF) front end 430. The RF front end 430 may include circuitry for transmitting and receiving radio signals. For example, the RF front end 430 may include receive circuitry (RX) 432 and transmit circuitry (TX) 434. In some aspects, the receive circuitry 432 may communicate with a downlink (DL) front end 450, which may include circuitry for receiving radio signals via the antenna 235a.

[0081] Similarly, the second modem 420 may include one or more processors 422 and a memory 426 in communication with the processor 422. The modem 420 may communicate with an RF front end 440. The RF front end 440 may include circuitry for transmitting and receiving radio signals. For example, the RF front end 440 may include receive circuitry 442 and transmit circuitry 444. In some aspects, the receive circuitry 442 may communicate with a DL front end 460, which may include circuitry for receiving radio signals via the antenna 235b.

[0082] In some aspects, the switch 470 can couple the transmit circuitry 434 to the uplink (UL) front end 472. Additionally, the switch 470 can couple the transmit circuitry 444 to the UL front end 472. The UL front end 472 can include circuitry for transmitting radio signals via the antenna 236. Thus, when the cellular communication circuitry 230 receives an instruction to transmit according to a first RAT (e.g., as supported via the first modem 410), the switch 470 can be switched to a first state that allows the first modem 410 to transmit signals according to the first RAT (e.g., via a transmit chain including the transmit circuitry 434 and the UL front end 472). Similarly, when the cellular communication circuitry 230 receives an instruction to transmit according to a second RAT (e.g., as supported via the second modem 420), the switch 470 can be switched to a second state that allows the second modem 420 to transmit signals according to the second RAT (e.g., via a transmit chain including the transmit circuitry 444 and the UL front end 472).

[0083] As described herein, the first modem 410 and / or the second modem 420 may include hardware and software components for implementing any of the various features and techniques described herein. For example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium), the processors 412, 422 may be configured to implement some or all of the features described herein. Alternatively (or in addition), the processors 412, 422 may be configured as programmable hardware elements, such as an FPGA (field programmable gate array) or as an ASIC (application-specific integrated circuit). Alternatively (or in addition), in combination with one or more of the other components 430, 432, 434, 440, 442, 444, 450, 470, 472, 235, and 236, the processors 412, 422 may be configured to implement some or all of the features described herein.

[0084] Furthermore, as described herein, processors 412, 422 may include one or more processing elements. Thus, processors 412, 422 may include one or more integrated circuits (ICs) configured to perform the functions of processors 412, 422. Furthermore, each integrated circuit may include circuits (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of processors 412, 422.

[0085] In some aspects, the cellular communication circuitry 230 may include only one transmit / receive chain. For example, the cellular communication circuitry 230 may not include the modem 420, the RF front end 440, the DL front end 460, and / or the antenna 235b. As another example, the cellular communication circuitry 230 may not include the modem 410, the RF front end 430, the DL front end 450, and / or the antenna 235a. In some aspects, the cellular communication circuitry 230 may also not include the switch 470, and the RF front end 430 or the RF front end 440 may communicate with the UL front end 472, for example, directly.

[0086] Related to the mismatch between the cell DTX / DRX cycle activity time and the valid RO within the PRACH associated period question

[0087] According to some aspects, adapting the cell DTX and / or DRX pattern to include alignment of the cell DTX / DRX cycle activity time with the UE DRX may benefit network energy conservation. Various mechanisms may be provided to inform the UE whether the cell it is communicating with remains inactive. Such mechanisms may include enhancements to traditional UE DRX configurations, for example, to align and / or omit the DRX cycle (or apply an offset to DRX) for UEs in connected mode or in idle / inactive mode, thereby potentially allowing longer cell inactivity opportunities. During the cell DTX / DRX cycle, the cell may not have transmit / receive capability, or the cell may only maintain limited transmit / receive capability. For example, the cell may not need to send or receive some periodic signals / channels, such as common channels / signals or UE-specific signals / channels.

[0088] For such legacy UEs, the UE may be configured with a DRX cycle, and the network may then stop transmitting during the UE DRX off (or "inactivity") period to save transmit energy. However, in a purely network-side implementation, the base station may still need to send or receive some periodic signals / channels, such as PRACH or Scheduling Request (SR).

[0089] Therefore, it would be beneficial to define a cell DRX pattern such that the gNB may also stop listening to the PRACH (or other periodic signals / channels) during certain intervals. For example, according to the embodiments disclosed herein, a cell DRX pattern may be configured in which the UE may transmit only during the cell DRX on duration (i.e., the “active time”). However, certain challenges may need to be overcome in achieving these goals. For example, due to a “mismatch” between the valid ROs within the active window and the PRACH associated pattern period, the UE may not be able to determine a valid RO associated to a desired synchronization signal / physical broadcast channel (i.e., “SS / PBCH”) block in the cell DRX active time. Additionally, ROs associated to different SS / PBCH blocks may have different densities within a given PRACH associated period, which may be due to a mismatch between the PRACH associated pattern period and the cell’s DRX cycle. (In some aspects, the SS / PBCH block index numbers may be associated with different gNB beams.)

[0090] Now go to Figure 5 , illustrating various diagrams 500 / 550 detailing examples of various issues caused by a mismatch between a cell DRX cycle active time and a valid RO within a PRACH associated period, according to some aspects.

[0091] Turning first to diagram 500, a PRACH association period 510 is shown that includes a determined set of valid ROs 505, which are shown as rectangles with the following indices: 0, 1, 2, 3, 4, 5, 6, and 7, repeating. Each valid RO 505 in diagram 500 is also shown as being associated with a specific SS / PBCH block index number 515, as shown by the repeating pattern of the block index numbers: 0, 1, 2, 0, 1, 2, repeating.

[0092] Diagram 500 also illustrates an exemplary cell DRX pattern 520 that includes one or more repeating cell DRX cycles 525. Each cell DRX cycle may include an active time or "on duration" period 526 during which the cell can receive transmissions from UEs and an inactive time or "off duration" period 530 during which the cell can save network energy by not receiving any UE transmissions. The longer the off duration 530 relative to the cell DRX cycle 525, the greater the energy savings that can be achieved by the network. For example, according to some implementations, the off duration can be at least 10 ms to 100 ms long, where the dynamic nature of the length of the off duration over time can be based on how dynamically the cell's traffic level changes during the operating period.

[0093] As can now be appreciated, due to the temporal "mismatch" between the active time window 526 and certain valid ROs 505 within the PRACH associated period 510, the UE may never be able to use the RO associated with SS / PBCH block index #2 (516) when that particular cell DRX pattern 520 is configured. In other words, the valid RO for SS / PBCH block index #2 will always correspond to the cell's inactivity, i.e., off duration period (530). In contrast, the valid RO for each of SS / PBCH block indices #0 and #1 does align or "match" in time with at least one active time window 526 of the cell DRX pattern 520 shown in diagram 500.

[0094] Turning now to diagram 550, another exemplary cell DRX pattern 560 is shown that includes one or more repeating cell DRX cycles 565. Each cell DRX cycle may include an active time or "on duration" period 566 (during which the cell is able to receive transmissions from UEs) and an inactive time or "off duration" period 570, wherein the cell is able to save network energy by not receiving any UE transmissions. In the example of diagram 550, due to the temporal "mismatch" between the active time window 566 and certain valid ROs 505 within the PRACH associated period 510, the "density" of valid ROs associated with SS / PBCH block index #1 (551) will always be higher than the "density" of valid ROs associated with SS / PBCH block indices #0 and #2. In other words, for every two valid ROs for SS / PBCH block index #1, there will only be a single valid RO for SS / PBCH block indices #0 and #2, which may be suboptimal (e.g., from a network access latency perspective).

[0095] Indication for mismatch between cell DTX / DRX cycle activity time and valid RO within PRACH associated period Example Solution

[0096] According to some embodiments disclosed herein, a Network Energy Saving (NES) cell DRX mode (e.g., also referred to herein as "cell DRX Mode A") may be defined such that, when configured, UEs are not expected to transmit during the off duration or "inactivity time" of the cell DRX cycle. In such embodiments, when the previously mentioned NES cell DRX Mode A is configured, the network may configure a separate, effective RO configuration for so-called "NES-capable" UEs. Preferably, this new RO configuration does not cause any UE behavior changes for legacy UEs and / or UEs that are not NES-capable.

[0097] According to some aspects, when cell DRX mode A is configured, one or more new valid RO determination criteria may be introduced for UEs with NES capabilities. According to cell DRX mode A, the valid RO may be determined according to the existing valid RO criteria and then further refined to exclude any RO that may occur temporally within the cell DRX off duration (i.e., inactivity time). According to other aspects, the SS / PBCH block index number association may be mapped only to the valid RO identified according to the new valid RO criteria, thereby improving upon the above, for example, reference to Figure 5 Preferably, the PRACH associated period may also be updated according to the determined new set of valid ROs (ie the ROs that remain after applying the cell DRX on duration criterion).

[0098] Now go to Figure 6A 、 Figure 6B , according to some aspects, various diagrams 600 / 630 / 660 are illustrated detailing exemplary solutions to the problem of mismatch between cell DRX cycle active time and valid RO within a PRACH associated period according to some aspects.

[0099] First go to Figure 6A 6, which includes a set of determined valid ROs 605, shown as rectangles with indices 0, 1, 2, 3, 4, 5, 6, and 7, which repeat. Each valid RO 605 corresponding to a cell DRX on duration (i.e., "Active Time") in FIG600 is also shown as being associated with a specific SS / PBCH block index number 615, as shown by the repeating pattern of the block index numbers: 0, 1, 2, 0, 1, 2, which repeat. Valid ROs 605 in FIG600 that do not correspond to a cell DRX on duration (i.e., "Active Time") are shown as not being associated with any specific SS / PBCH block index number 615, but are instead marked with an "X" character.

[0100] As explained, for example, in 3GPP TS 38.213 (version 17.1.0) in section 8.1, the association period for mapping SS / PBCH block indices to PRACH opportunities starting from frame 0 is the minimum value in the set determined by the PRACH configuration period according to Table 8.1-1, such that The SS / PBCH block index is mapped to a PRACH opportunity at least once within the associated period, where the UE obtains the value of ssb-PositionsInBurst from SIB1 or ServingCellConfigCommon If an integer number of SS / PBCH block indices within the associated period are not mapped to a PRACH opportunity after the mapping cycle, If there is no SS / PBCH block index mapped to a set of PRACH opportunities or PRACH preambles, then no SS / PBCH block index is mapped to a set of PRACH opportunities or PRACH preambles.

[0101] exist Figure 6A In the example shown in diagram 600 of FIG, the PRACH configuration period 611 (i.e., the time period between RO 0 and RO 7) can be considered to be 20 ms. Therefore, the minimum value from 3GPP TS 38.213 Table 8.1-1 for mapping SS / PBCH block indices 0-2 to valid ROs at least once is two (i.e., because there are only two valid ROs in the PRACH configuration period 611). Therefore, in the example shown in diagram 600, the PRACH association period 610 is 40 ms (i.e., the duration of two PRACH configuration periods 611).

[0102] In contrast, Figure 6A In the example shown in diagram 630 in FIG, the minimum value from 3GPP TS 38.213 Table 8.1-1 for mapping SS / PBCH block indices 0-2 to a valid RO once is 1 (i.e., because there are four valid ROs in the PRACH configuration period 641). Therefore, in the example shown in diagram 630, the PRACH association period 640 is 20 ms (i.e., the duration of a single PRACH configuration period 641).

[0103] Returning to diagram 600, an exemplary cell DRX pattern 620 is shown that includes one or more repeating cell DRX cycles 625. Each cell DRX cycle may include an active time or "on duration" period 626 (during which the cell is able to receive transmissions from the UE) and an inactive time or "off duration" period 630. n , where the cell is able to save network energy by not receiving any UE transmissions. As can now be appreciated, due to the application of the additional valid RO criteria, there are no longer any instances of temporal "mismatches" between the valid ROs 605 associated to the SS / PBCH block index (615) within the active time window 626 and the PRACH association period 610. Similarly, the "density" of each SS / PBCH block index (615) appears equal. In other words, the SS / PBCH block indices associated with the valid ROs during the cell DRX active time will follow a repeating pattern of #0, #1, #2, #0, #1, #2, etc., such that there is a balanced number of ROs for each SS / PBCH block index.

[0104] Next go to Figure 6A630, another exemplary cell DRX pattern 650 is shown that includes one or more repeating cell DRX cycles 655. As mentioned above, in the example of diagram 630, the duration of the PRACH association period 640 is shown to be equal to the duration of a single PRACH configuration period 641 (e.g., 20 ms). Each cell DRX cycle 655 may again include an active time or "on duration" period 659 (during which the cell is able to receive transmissions from the UE) and an inactive time or "off duration" period 658. n , where the cell is able to save network energy by not receiving any UE transmissions.

[0105] In the example of diagram 630, the cell DRX cycle 655 is approximately half the duration of the cell DRX cycle 625 illustrated in diagram 600. However, again, due to the application of the additional valid RO criteria, there are no longer any instances of temporal "mismatches" between the active time window 659 and the set of determined valid ROs 635 associated to SS / PBCH block indices (645) within the PRACH association period 640. Similarly, the "density" of each SS / PBCH block index (645) appears equal. In other words, the SS / PBCH block indices associated with valid ROs during the cell DRX active time will follow a repeating pattern of #0, #1, #2, #0, #1, #2, etc., such that there are a balanced number of ROs for each SS / PBCH block index. It should also be noted that, depending on some configurations, there may be one or more ROs that are "valid" but not mapped to a particular SS / PBCH block index number (e.g., 646).

[0106] According to some aspects, the additional effective RO criteria described herein (i.e., taking into account the cell DRX cycle "on duration") can be applied to NES-capable UEs in idle, inactive, and / or connected modes. When NES cell DRX "Mode A" is configured for a particular cell, the network can offload legacy UEs to non-DRX cells, while NES-capable UEs can remain in the NES cell, thereby enabling complete shutdown.

[0107] According to other aspects, additional valid RO criteria may only apply to NES-capable UEs in connected mode (while idle and inactive mode UEs may still perform the "regular" valid RO determination process, i.e., without considering the cell DRX cycle on duration). To achieve even greater network energy savings, the network may reconfigure the RO configuration for idle and / or inactive mode UEs such that RO outside the cell's DRX on duration period is minimized to the greatest extent possible. Alternatively, the network may simply offload these UEs to a different cell. On the other hand, for non-NES-capable UEs, the network may reconfigure the RO configuration such that RO outside the cell's DRX on duration period is minimized to the greatest extent possible, using system information blocks (SIBs) or dedicated radio resource control (RRC) signaling.

[0108] Another UE behavior to consider when developing improved RO determination criteria for cells operating in DRX and / or DTX mode is the reception of a Random Access Response (RAR) message (i.e., Msg2). According to some aspects, the improved UE behavior for receiving RAR can be determined based on the cell's DTX mode and / or the NES cell DTX mode. For example, if NES cell DTX "Mode A" (i.e., the most aggressive power saving mode) is configured, the gNB may not transmit at all during the OFF duration of the cell's DTX cycle. In one example, the window for receiving the RAR window may span only the ON duration, i.e., the timer for RAR may simply be suspended during any DTX OFF duration. In other words, the RA-ResponseWindow can be configured to be suspended outside of the active time of the cell's DTX cycle.

[0109] In another example, only ROs in the "front" position will be sent, i.e., those ROs that leave enough time for receiving the RAR message within the active period. In other words, this new valid RO criterion is needed to ensure that the UE can always find a valid RO during the on duration period, i.e., only ROs that are within the on duration and leave enough time for the RAR message are considered valid ROs and used for RACH transmission.

[0110] Now go to Figure 6B FIG660 shows another exemplary cell DRX pattern 680 that includes one or more repeating cell DRX cycles 685. Each cell DRX cycle may include an active time or "on duration" period 686 during which the cell can receive transmissions from the UE and an inactive time or "off duration" period 690. n, where the cell is able to save network energy by not receiving any UE transmissions. In the example of diagram 660, due to the application of the additional valid RO criteria, there is still no instance of a time "mismatch" between the active time window 686 and the set of determined valid ROs 665 associated to the SS / PBCH block index (675) within the PRACH association period 670. Similarly, the "density" of each SS / PBCH block index (675) appears equal. In other words, the SS / PBCH block indexes associated with valid ROs during the cell DRX active time will follow a repeating pattern of #0, #1, #2, #0, #1, #2, etc., so that there are a balanced number of ROs for each SS / PBCH block index. However, due to the additional criteria regarding leaving enough time for RAR, in the example of diagram 660, only ROs in the "front" position are considered valid, for example, as illustrated by the "X" characters in ROs 676 and 677, which appear in the "back" position (and therefore do not leave enough time to deliver the RAR message). Therefore, the PRACH association period 670 may need to be extended again (i.e., to the duration of two PRACH configuration periods 671) because fewer ROs pass the additional validity criteria. However, over a sufficient period of time, the valid ROs will follow the expected repeating pattern of #0, #1, #2, #0, #1, #2, etc., so that there are a balanced number of ROs for each SS / PBCH block index. In other words, according to some aspects, determining a valid RO may further include determining that the last symbol of the RO is at least a threshold number N symbols before the last symbol of the active time of the given DRX cycle in which the RO is located.

[0111] According to other aspects, a different cell DTX "Mode B" (i.e., a less aggressive mode in terms of energy conservation) may be configured, in which conventional mechanisms for determining the RAR window may be used. In this cell DTX Mode B, the UE may still monitor for RAR messages during the cell DTX OFF duration, i.e., the cell's DTX ON duration may be extended for the limited purpose of sending the RAR.

[0112] Exemplary Methods

[0113] Now go to Figure 7 According to some aspects, a flow chart of a method 700 for performing effective RO determination when a cell operates in DRX mode is detailed. First, at block 702, a UE practicing the method 700 may send a first capability indication from a user equipment (UE) to a base station, wherein the first capability indication indicates that the UE has network energy saving (NES) capability and / or that the UE is capable of applying one or more effective physical random access channel (RACH) opportunity (RO) criteria.

[0114] Next, at block 704, method 700 may receive, at a UE, a first RO configuration and a first discontinuous reception (DRX) mode configuration from a base station, wherein the first DRX mode configuration specifies a DRX cycle used by the base station.

[0115] Next, at block 706, method 700 may determine, by the UE, a first set of valid ROs for sending a RACH message to the base station, wherein determining the first set of valid ROs further comprises determining an active time during which the base station will be in a first DRX mode.

[0116] Next, at block 708, method 700 may send a first RACH message (eg, Msg1) from the UE to the base station during a first valid RO in the determined first set of valid ROs.

[0117] Next, at block 710, method 700 may optionally determine, by the UE, a second valid RO from the determined first set of valid ROs for use in sending a second RACH message to the base station.

[0118] Finally, at box 712, method 700 may optionally send a second RACH message from the UE to the base station during the determined second valid RO (e.g., where the second valid RO is associated with a second SS / PBCH block index, and where the second SS / PBCH block index is different from the first SS / PBCH block index associated with the first valid RO).

[0119] It should be understood that the discussion of using a first valid RO and a second valid RO in method 700 is not intended in any way to limit the scope of the present embodiment to a set or a specific number of valid ROs within a RACH associated period. Figure 6A and Figure 6B As illustrated and described, multiple valid ROs can be determined, each associated with a different SS / PBCH block index (if necessary), and the multiple valid ROs can be used to send RACH messages during a given RACH association period, thereby ensuring that each determined valid RO will send a RACH message during the active time of the first DRX mode in which the base station is currently operating.

[0120] As can now be appreciated, the benefits of the various embodiments disclosed herein may include providing greater network configuration flexibility to achieve different levels of network energy savings. For example, when configured as "Cell DRX Mode A" and "Cell DTX Mode A," the network may be able to achieve maximum energy savings, i.e., where the cell completely stops monitoring the PRACH preamble during the Cell DRX Off duration and completely stops sending RARs during the Cell DTX Off duration. Intelligent network configuration may be employed to balance the desired energy savings with UE network access latency (e.g., if Cell DRX Mode A is configured, but "Cell DTX Mode B" is configured in a given setup).

[0121] It should also be understood that similar techniques to those disclosed herein (i.e., applying additional criteria that take into account call DRX and / or DTX cycles) may also be applied to other common signals and / or channels in NR or higher releases, such as common CORESET reception, paging, etc.

[0122] Additional Notes

[0123] The use of the conjunction "and / or" is intended to represent all possible alternatives of the conjunction "and" and the conjunction "or." For example, the sentence "the configuration of A and / or B" includes the meaning of the sentence "the configuration of A and B" and "the configuration of A or B."

[0124] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of authorized use should be clearly stated to users.

[0125] Aspects of the present disclosure can be implemented in any of a variety of forms. For example, some aspects can be implemented as computer-implemented methods, computer-readable storage media, or computer systems. Other aspects can be implemented using one or more custom-designed hardware devices such as ASICs. Other aspects can be implemented using one or more programmable hardware elements such as FPGAs.

[0126] In some aspects, a non-transitory computer-readable storage medium may be configured such that it stores program instructions and / or data, where the program instructions, when executed by a computer system, cause the computer system to perform a method (e.g., any of the method aspects described herein, or any combination of the method aspects described herein, or any subset of any of the method aspects described herein, or any combination of such subsets).

[0127] In some aspects, a device (e.g., UE 106, BS 102) may be configured to include a processor (or a group of processors) and a memory medium, wherein the memory medium stores program instructions, wherein the processor is configured to read and execute the program instructions from the memory medium, wherein the program instructions are executable to implement any of the various method aspects described herein (or any combination of the method aspects described herein, or any subset of any method aspects of the method aspects described herein, or any combination of such subsets). The device may be implemented in any of various forms.

[0128] Although the above aspects have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to encompass all such variations and modifications.

Claims

1. A method of operating a user equipment (UE), the method comprising: sending a first capability indication from the UE to a base station, wherein the first capability indication indicates that the UE has a network energy saving (NES) capability; receiving, at the UE, a first physical random access channel (RACH) opportunity (RO) configuration and a first discontinuous reception (DRX) mode configuration from the base station, wherein the first DRX mode configuration specifies a DRX cycle used by the base station; determining, by the UE, a first set of valid ROs for use in sending a RACH message to the base station, wherein determining the first set of valid ROs further comprises determining an active time during which the base station will be in the first DRX mode during the first set of valid ROs; as well as A first RACH message is sent from the UE to the base station during a first valid RO in the determined first set of valid ROs.

2. The method of claim 1, wherein the first RACH message comprises a random access preamble (Msg1) message.

3. The method of claim 1, wherein the first valid RO is associated with a first synchronization signal / physical broadcast channel (SS / PBCH) block index.

4. The method according to claim 3, further comprising: Determining, by the UE, a second valid RO from the determined first set of valid ROs for sending a second RACH message to the base station; as well as The second RACH message is sent from the UE to the base station during the determined second valid RO period.

5. The method of claim 4, wherein the second valid RO is associated with a second SS / PBCH block index, and wherein the second SS / PBCH block index is different from the first SS / PBCH block index.

6. The method of claim 1, wherein each SS / PBCH block in a set of SS / PBCH blocks is associated with at least one RO in the first set of valid ROs.

7. The method of claim 1, wherein the base station is further configured to use a first discontinuous transmission (DTX) mode.

8. The method according to claim 7, wherein the base station is configured not to transmit to the UE outside the active time of the DTX cycle configured in the first DTX mode.

9. The method according to claim 8, further comprising: A random access response (RAR) message sent from the base station in response to the first RACH message is received at the UE.

10. The method of claim 9, wherein ra-ResponseWindow is configured to be suspended outside the active time of the DTX cycle.

11. The method according to claim 9, further comprising: determining the first valid RO in the determined first set of valid ROs, Determining the first valid RO further includes determining that a last symbol of the first valid RO is at least a threshold number N symbols before a last symbol of an active time of a DRX cycle in which the first valid RO is located.

12. The method of claim 1, wherein the first capability indication further indicates that the UE is capable of applying one or more valid RO criteria when determining the first set of valid ROs.

13. The method according to claim 1, wherein the UE is in RRC_CONNECTED state.

14. A user equipment (UE) device, the user equipment (UE) device comprising: Receiver; transmitter; and a processor configured to perform any action or combination of actions described in any of the methods according to claims 1 to 13.

15. A non-transitory computer readable medium storing instructions which, when executed, cause any action or combination of actions described in any of the methods according to claims 1 to 13 to be performed.

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