Anchor carrier for network power savings

Abstract

A user equipment (UE) is configured to perform initial access on an anchor carrier of a fifth generation (5G) new radio (NR) network and monitor a non-anchor carrier for unicast transmission, wherein the non-anchor carrier does not broadcast a synchronization signal block (SSB). In some cases, the non-anchor carrier does not broadcast a system information block (SIB).

Description

[0001] Priority / Claim Incorporation

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 378,951, filed on October 10, 2022, entitled "Anchor Carrier for Network Energy Saving", the entire disclosure of which is incorporated herein by reference. Background Art

[0003] In a multi-carrier deployment scenario, a user equipment (UE) may be configured with an anchor carrier and non-anchor carriers. It has been recognized that the use of an anchor carrier can provide network energy saving benefits. Therefore, there is a need for technologies configured to support the implementation of an anchor carrier for network energy saving. Summary of the Invention

[0004] Some example embodiments relate to an apparatus for a user equipment (UE) having processing circuitry configured to perform initial access on an anchor carrier of a fifth generation (5G) new radio (NR) network and monitor a non-anchor carrier for unicast transmissions, where the non-anchor carrier does not broadcast a synchronization signal block (SSB).

[0005] Other example embodiments relate to a method performed by a user equipment (UE). The method includes performing initial access on an anchor carrier of a fifth generation (5G) new radio (NR) network and monitoring a non-anchor carrier for unicast transmissions, where the non-anchor carrier does not broadcast a synchronization signal block (SSB). Brief Description of the Drawings

[0006] Figure 1 An exemplary network arrangement is shown in accordance with various example embodiments.

[0007] Figure 2 An exemplary user equipment (UE) is shown in accordance with various example embodiments.

[0008] Figure 3 An exemplary base station is shown in accordance with various example embodiments.

[0009] Figure 4 A method for anchor carrier operation is shown in accordance with various example embodiments. Detailed Description

[0010] The example embodiments may be further understood with reference to the following description and the related drawings, in which like elements are provided with like reference numerals. The example embodiments present technologies that support the implementation of an anchor carrier for network energy saving.

[0011] Exemplary embodiments are described with respect to a user equipment (UE). However, the reference to the UE is provided for illustrative purposes only. The exemplary embodiments may be used with any electronic component that can establish a connection with a network and is configured with hardware, software, and / or firmware for exchanging information and data with the network. Thus, the UE described herein is used to represent any electronic component.

[0012] Exemplary embodiments are also described with reference to a fifth generation (5G) new radio (NR) network. However, the reference to the 5G NR network is provided for illustrative purposes only. The exemplary embodiments may be used with any suitable type of network that can achieve network energy savings using an anchor carrier.

[0013] Exemplary embodiments are described with reference to a multi-carrier deployment scenario that includes at least a first carrier and a second carrier. Those skilled in the art will understand that a carrier generally refers to one or more frequency bands operated by a cell of a base station (e.g., a gNB). Throughout the specification, to distinguish different carriers, "carrier 1" and "carrier 2" may be referred to. However, any reference to carrier 1 or carrier 2 having certain characteristics or exhibiting specific behaviors is provided only as a non-limiting example. The classification of carrier 1 and carrier 2 is not intended to limit the exemplary embodiments in any way and is only intended to distinguish carriers in a multi-carrier deployment scenario. The exemplary embodiments described herein may be used by a multi-carrier system that includes any number of carriers deployed by any suitable number of base stations.

[0014] In some multi-carrier deployment scenarios, a carrier may be configured as an anchor carrier or a non-anchor carrier. Generally speaking, the term "anchor carrier" may refer to a carrier on which a UE is assumed to send certain types of synchronization information. To provide some non-limiting examples, a UE may assume that the anchor carrier will send a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a physical broadcast channel (PBCH), system information block 1 (SIB1), a random access channel (RACH), and paging. The term "non-anchor" carrier may refer to a carrier on which a UE is assumed not to send certain types of synchronization information. A general overview of anchor carrier operation is provided in the following paragraphs to illustrate some non-limiting examples of the interactions that may occur between a UE, an anchor carrier, and a non-anchor carrier in a multi-carrier system. However, the various examples provided throughout this specification are not intended to limit the scope of the terms "anchor carrier" and "non-anchor carrier" in any way. The terms "anchor carrier" and "non-anchor carrier" are defined in various 3GPP documents. The anchor carriers and non-anchor carriers described herein may behave in the manner in which they are defined in the 3GPP documents and in accordance with the exemplary embodiments described herein.

[0015] To provide a general overview of multi-carrier deployment scenarios involving anchor carriers and non-anchor carriers, consider a scenario in which a UE resides on a cell operating on carrier 1. Initially, the UE may perform a RACH procedure using carrier 1 for initial access to the 5G NR network. After the RACH procedure is completed, the UE may be configured with one or more non-anchor carriers (e.g., carrier 2, etc.). When the UE operates in a radio resource control (RRC) connected mode (e.g., physical downlink control channel (PDCCH), physical uplink control channel (PUCCH), physical downlink shared channel (PDSCH), physical uplink shared channel (PUSCH), etc.), the UE may exchange data on a non-anchor carrier. However, non-anchor carriers may not send certain types of synchronization information (e.g., SSB, PBCH, SIB1, etc.), which may provide energy saving opportunities on the network side. Although the exemplary embodiment supports the implementation of an anchor carrier for network energy saving, the specific network energy saving techniques are beyond the scope of the exemplary embodiment, and the exemplary embodiment may be used regardless of whether network energy saving is implemented.

[0016] The exemplary embodiments present techniques to support the implementation of an anchor carrier for network energy conservation. As will be described in more detail below, the exemplary embodiments relate to various aspects of a multi-carrier system, such as, but not limited to, collecting measurement data from an anchor carrier, collecting measurement data from a non-anchor carrier, radio link monitoring (RLM), beam failure, RACH, and paging. The exemplary techniques introduced herein can be used independently of each other, in conjunction with other currently implemented anchor carrier mechanisms, in conjunction with future implementations of anchor carrier mechanisms, and independently of other anchor carrier mechanisms.

[0017] Figure 1 An exemplary network arrangement 100 according to various exemplary embodiments is shown. The exemplary network arrangement 100 includes a UE 110. Those skilled in the art will appreciate that the UE 110 may be any type of electronic component configured to communicate via a network, such as a mobile phone, a tablet computer, a desktop computer, a smart phone, a phablet, an embedded device, a wearable device, an Internet of Things (IoT) device, etc. It should also be appreciated that an actual network arrangement may include any number of UEs used by any number of users. Therefore, the example of a single UE 110 is provided for illustrative purposes only.

[0018] The UE 110 may be configured to communicate with one or more networks. In an example of network configuration 100, the network with which the UE 110 may communicate wirelessly is a 5G NR radio access network (RAN) 120. However, the UE 110 may also communicate with other types of networks (e.g., 6G RAN, 5G cloud RAN, next-generation RAN (NG-RAN), long-term evolution (LTE) RAN, legacy cellular networks, wireless local area network (WLAN), etc.), and the UE 110 may also communicate with a network via a wired connection. Referring to the exemplary implementation, the UE 110 may establish a connection with the 5G NR RAN 120. Thus, the UE 110 may at least have a 5G NR chipset to communicate with the NR RAN 120.

[0019] The 5G NR RAN 120 may be part of a cellular network that may be deployed by a network operator (e.g., Verizon, AT&T, T-Mobile, etc.). The 5G NR RAN 120 may include, for example, base stations or access nodes (NodeB, eNodeB, HeNB, eNBS, gNB, gNodeB, macro cell, micro cell, small cell, femto cell, etc.) configured to transmit and receive communication traffic from UEs equipped with appropriate cellular chipsets.

[0020] Those skilled in the art will understand that any relevant process may be executed for the UE 110 to connect to the 5G NR RAN 120. For example, as discussed above, the 5G NR RAN 120 may be associated with a specific cellular provider where the UE 110 and / or its user have protocol and credential information (e.g., stored on a SIM card). Upon detecting the presence of the 5G NR RAN 120, the UE 110 may send the corresponding credential information to associate with the 5G NR RAN 120. More specifically, the UE 110 may associate with a specific base station (e.g., gNB 120A).

[0021] The exemplary implementation relates to a multi-carrier deployment scenario. In network arrangement 100, the gNB 120A may control multiple cells each operating on a different carrier (e.g., carrier 1, carrier 2, etc.). For example, both carrier 1 and carrier 2 may be deployed by the gNB 120A. However, the reference to a single gNB deploying multiple carriers is provided merely for illustrative purposes. In an actual network arrangement, any number of base stations may deploy any appropriate number of carriers.

[0022] The network arrangement 100 further includes a cellular core network 130, the Internet 140, an IP Multimedia Subsystem (IMS) 150, and a network service backbone 160. The cellular core network 130 may refer to an interconnected collection of components that manage the operation and traffic of a cellular network. It may include an Evolved Packet Core (EPC) and / or a 5G Core (5GC). The cellular core network 130 also manages the traffic flowing between the cellular network and the Internet 140. The IMS 150 can generally be described as an architecture for delivering multimedia services to the UE 110 using IP protocols. The IMS 150 can communicate with the cellular core network 130 and the Internet 140 to provide multimedia services to the UE 110. The network service backbone 160 communicates directly or indirectly with the Internet 140 and the cellular core network 130. The network service backbone 160 can generally be described as a collection of components (e.g., servers, network storage arrangements, etc.) that implement a set of services that can be used to extend the functionality of the UE 110 to communicate with various networks.

[0023] Figure 2 An exemplary UE 110 is shown in accordance with various exemplary embodiments. The UE 110 will be described with reference to Figure 1 the network arrangement 100. The UE 110 may include a processor 205, a memory arrangement 210, a display device 215, an input / output (I / O) device 220, a transceiver 225, and other components 230. The other components 230 may include, for example, an audio input device, an audio output device, a power supply, a data acquisition device, ports for electrically connecting the UE 110 to other electronic devices, etc.

[0024] The processor 205 may be configured to execute multiple engines of the UE 110. For example, the engines may include a multi-carrier operation engine 235. The multi-carrier operation engine 235 may perform various operations related to the exemplary techniques introduced herein, such as but not limited to receiving configuration information, collecting measurement data, performing operations of the RACH procedure, tuning the transceiver 225 to an anchor carrier, tuning the transceiver 225 to a non-anchor carrier, performing operations of the BFR, performing operations of the RLM, monitoring paging, and receiving paging.

[0025] The engine 235 cited above is provided only for illustrative purposes as an application (e.g., a program) executed by the processor 205. The functionality associated with the engine 235 may also be represented as separate combined components of the UE 110 or may be modular components coupled to the UE 110, e.g., integrated circuits with or without firmware. For example, the integrated circuit may include an input circuit for receiving signals and a processing circuit for processing the signals and other information. The engine may also be embodied as one application or multiple separate applications. Additionally, in some UEs, the functionality described for the processor 205 is split between two or more processors, such as a baseband processor and an application processor. The exemplary embodiments may be implemented in any of these or other configurations of the UE.

[0026] The memory arrangement 210 may be a hardware component configured to store data related to operations performed by the UE 110. The display device 215 may be a hardware component configured to display data to a user, while the I / O device 220 may be a hardware component that enables a user to type in an input. The display device 215 and the I / O device 220 may be separate components or may be integrated together (such as a touchscreen).

[0027] The transceiver 225 may be a hardware component configured to establish connections with the 5G NR-RAN 120, LTE-RAN (not shown in the figure), legacy RAN (not shown in the figure), WLAN (not shown in the figure), etc. Thus, the transceiver 225 may operate on a variety of different frequencies or channels (e.g., a set of contiguous frequencies). The transceiver 225 includes circuits configured to transmit and / or receive signals (e.g., control signals, data signals). Such signals may be encoded with information implementing any of the methods described herein. The processor 205 may be operably coupled to the transceiver 225 and is configured to receive signals from the transceiver 225 and / or transmit signals to the transceiver 225. The processor 205 may be configured to encode and / or decode signals (e.g., signaling from a base station of a network) for implementing any of the methods described herein.

[0028] Figure 3 An exemplary base station 300 is shown in accordance with various exemplary embodiments. The base station 300 may represent the gNB 120A or any other access node by which the UE 110 may establish connections and manage network operations.

[0029] The base station 300 may include a processor 305, a memory arrangement 310, an input / output (I / O) device 315, a transceiver 320, and other components 325. These other components 325 may include, for example, an audio input device, an audio output device, a battery, a data acquisition device, ports for electrically connecting the base station 300 to other electronic devices and / or a power source, etc.

[0030] The processor 305 can be configured to execute multiple engines of the base station 300. For example, the engines can include an anchor carrier engine 330 and a non-anchor carrier engine 335. The anchor carrier engine 330 can perform various operations of the anchor carrier deployed by the base station 300. The non-anchor carrier engine 335 can perform various operations of the non-anchor carrier deployed by the base station 300.

[0031] The above engines 330, 335 are only exemplary as application programs (e.g., programs) executed by the processor 305. The functions associated with the engines 330, 335 can also be represented as separate integrated components of the base station 300, or can be modular components coupled to the base station 300, e.g., an integrated circuit with or without firmware. For example, the integrated circuit can include an input circuit for receiving signals and a processing circuit for processing signals and other information. Additionally, in some base stations, the functionality described for the processor 305 is split among multiple processors (e.g., a baseband processor, an application processor, etc.). The exemplary embodiments can be implemented in any of these or other configurations of the base station.

[0032] The memory 310 can be a hardware component configured to store data related to the operations performed by the base station 300. The I / O device 315 can be a hardware component or port that enables a user to interact with the base station 300.

[0033] The transceiver 320 can be a hardware component configured to exchange data with the UE 110 and any other UE in the network arrangement 100. The transceiver 320 can operate on various different frequencies or channels (e.g., a set of contiguous frequencies). Thus, the transceiver 320 can include one or more components (e.g., radio devices) to enable data exchange with various networks and UEs. The transceiver 320 includes circuits configured to transmit and / or receive signals (e.g., control signals, data signals). Such signals can be encoded with information implementing any of the methods described herein. The processor 305 can be operably coupled to the transceiver 320 and is configured to receive signals from the transceiver 320 and / or send signals to the transceiver. The processor 305 can be configured to encode and / or decode signals (e.g., signaling from the UE) for implementing any of the methods described herein.

[0034] Figure 4 A method 400 for anchor carrier operation according to various exemplary embodiments is shown. The method 400 is described with reference to Figure 1 the network arrangement 100 and from the perspective of the UE 110.

[0035] In 405, the UE 110 performs initial access on an anchored carrier. The initial access procedure may include a two-step RACH procedure including message A (msgA) and msg B or a four-step RACH procedure including msg 1, msg 2, msg 3, and msg 4. In addition, the initial access may include other operations such as, but not limited to, cell search and paging.

[0036] As pointed out above, from the perspective of the UE 110, the anchored carrier may be a carrier on which the UE 110 assumes to send certain types of synchronization information (e.g., PSS, SSS, PBCH, SIB1, RACH, paging, etc.). In addition, the anchored carrier can be used for broadcast and / or multicast transmissions. Therefore, the UE 110 can receive broadcast and / or multicast signaling via the anchored carrier.

[0037] In 410, the UE 110 is configured with one or more non-anchored carriers. For example, after completing the RACH (e.g., after receiving msg 4 in the four-step RACH or msg B in the two-step RACH), the UE 110 can be configured with one or more non-anchored carriers via RRC. When the UE 110 is in the RRC connected mode, the UE 110 can monitor one or more non-anchored carriers for unicast transmissions.

[0038] As pointed out above, from the perspective of the UE 110, the non-anchored carrier may be a carrier on which the UE 110 assumes not to send certain types of synchronization information (e.g., PSS, SSS, PBCH, SIB1, etc.). Therefore, the UE 110 can use the non-anchored carrier to exchange data in the uplink and / or downlink, but may not receive certain types of synchronization information on the non-anchored carrier.

[0039] In some embodiments, if more than one non-anchored carrier is configured, the UE 110 can select one of these non-anchored carriers. In other embodiments, when more than one non-anchored carrier is configured, the network can explicitly indicate which non-anchored carrier will be selected for transmission. For example, an RRC message, downlink control information (DCI), or medium access control (MAC) control element (CE) can be configured to indicate which non-anchored carrier the UE 110 will select.

[0040] According to some aspects, exemplary embodiments introduce techniques for obtaining timing information of non-anchor carriers based on anchor carrier timing and offset. For example, UE 110 may obtain the timing information of the anchor carrier based on the SSB broadcast by the anchor carrier. In this example, this may occur during initial access (e.g., 405). Then, UE 110 may derive the slot timing of the non-anchor carrier based on the timing and offset values of the anchor carrier. The offset value between the anchor carrier and the non-anchor carrier may be configured via RRC or in any other suitable manner. In this example, this may be when configuring the non-anchor carrier in 410. In some embodiments, the offset value may be configured on a per non-anchor carrier basis. In other embodiments, the offset value may be common to a group of non-anchor carriers.

[0041] According to some aspects, exemplary embodiments introduce techniques related to uplink power control on non-anchor carriers. Those skilled in the art will understand that uplink power control refers to a mechanism that allows UE 110 to determine the power to be used for certain types of uplink transmissions (e.g., PUSCH, PUCCH, sounding reference signal (SRS), physical RACH (PRAHC), etc.). Power control is based on path loss estimation and can be derived by UE 110 using a formula that includes at least a preconfigured received power target, assuming full path loss compensation (P 0 ) and a power control factor (α). The parameters (P 0 ) and (α) can be configured in RRC on a per non-anchor carrier basis, or can be common to a group of non-anchor carriers, or common to all non-anchor carriers.

[0042] In one method, the path loss of the non-anchor carrier can be estimated based on the SSB transmitted by the anchor carrier and the offset value provided by the network via RRC signaling. In some embodiments, the offset value can be configured on a per non-anchor carrier basis. In other embodiments, the offset value can be common to a group of non-anchor carriers. Thus, UE 110 can estimate the path loss of the non-anchor carrier for uplink power control based on the signal transmitted by the anchor carrier.

[0043] In another method, the path loss of the non-anchor carrier can be estimated based on the network-configured (e.g., gNB 120A) channel state information (CSI)-reference signal (RS) transmitted by the non-anchor carrier. Thus, contrary to the above method, UE110 can estimate the path loss of the non-anchor carrier for uplink power control based on the signal transmitted by the non-anchor carrier.

[0044] At 415, the UE 110 collects measurement data from a non-anchored carrier. At 420, the UE 110 collects measurement data from an anchored carrier. For example, once configured with one or more non-anchored carriers, the UE 110 can tune its transceiver 225 between the anchored carrier and the non-anchored carrier to collect measurement data and / or maintain a connection (e.g., beam failure, RLM, RRM, etc.). According to some aspects, an exemplary implementation introduces a retuning gap pattern for the UE 110 to switch between an anchored carrier and a non-anchored carrier.

[0045] The retuning gap pattern can be configured via RRC or in any other suitable manner. The retuning gap pattern can include a retuning gap that represents the duration for which the UE 110 can monitor the anchored carrier. To provide a general example, consider a scenario where the retuning gap pattern is configured with a retuning gap length of (Y) seconds and a repetition period of (X) seconds. First, a first retuning gap is triggered. The UE can tune its transceiver 225 from the non-anchored carrier to the anchored carrier. After the retuning gap duration expires, the UE 110 can tune back to the non-anchored carrier. (X) seconds after the first retuning gap, a second retuning gap can be triggered. The UE 110 can again tune its transceiver 225 from the non-anchored carrier to the anchored carrier for (Y) seconds. The above example is provided only as a general example of the retuning gap pattern and is not intended to limit the exemplary implementation in any way.

[0046] When in the RRC connected mode, the UE 110 can perform measurements on the anchored carrier based on the SSB broadcast by the anchored carrier. As noted above, in some implementations, the UE 110 can perform these measurements during a periodic retuning gap. For example, the UE 110 can tune away from the non-anchored carrier to the anchored carrier during the retuning gap and measure the anchored carrier based on the SSB. Then, the UE 110 can retune back to the same anchored carrier after the retuning gap. In this example, the parameters for the retuning gap pattern can be configured via RRC signaling or in any other suitable manner.

[0047] In other embodiments, a one-shot retuning gap may be configurable. In this method, the network may configure one or more retuning gap parameters via RRC. Then, the network may trigger the UE 110 to use the retuning gap configuration via DCI or MAC CE. For example, the UE 110 may receive the retuning gap parameters from the network via RRC signaling. Then, the UE 110 may receive DCI or MAC CE that triggers one of the previously configured retuning gap parameters. In response, the UE 110 may tune away from the non-anchor carrier to the anchor carrier during the retuning gap and measure the anchor carrier based on the SSB. Then, the UE 110 may retune back to the same anchor carrier after the retuning gap.

[0048] In other embodiments, the UE 110 may autonomously trigger retuning gap measurements for the anchor cell based on one or more predetermined conditions. For example, the UE 110 may identify network conditions and / or operations that trigger a timer for the UE 110 to utilize the retuning gap. The UE 110 may tune away from the non-anchor carrier to the anchor carrier during the retuning gap and measure the anchor carrier based on the SSB. Then, the UE 110 may retune back to the same anchor carrier after the retuning gap.

[0049] In another method, when the UE 110 is in the RRC connected mode, the UE 110 may perform measurements on the non-anchor carrier based on CSI-RS transmitted on the non-anchor carrier with a configurable offset. The offset is used to compensate for differences caused by measurements of different types of reference signals (e.g., SSB of the anchor carrier, CSI-RS on the non-anchor carrier, etc.). The offset value may be configured for each non-anchor carrier or may be a common configuration for a set of non-anchor carriers.

[0050] As noted above, the measurements performed in 415 - 420 may be used for RLM and RRM. The following techniques may be used to perform RLM and / or RRM in a multi-carrier system configured to support an anchor carrier.

[0051] In one method, the UE 110 may perform RLM on an anchor carrier together with connected mode RRM. In some embodiments, the same retuning gap may be used to collect measurement data for both RLM and RRM. In other embodiments, at least one retuning gap may be configured for RRM, and at least one other retuning gap may be configured for RLM. For example, a first periodic retuning gap pattern may be configured for RRM, and a second different periodic retuning gap pattern may be configured for RLC. As another example, a single periodic measurement gap may be configured, where a subset of the retuning gaps is configured for RLC, and a different subset of the retuning gaps may be configured for RRM. As yet another example, a single retuning gap may be configured for RLC and / or RRM. The network may indicate the retuning gap length and indicate whether the gap is for RLC, RRM, or both. In some embodiments, the network may configure the retuning gap and then use layer 1 (L1) / layer 2 (L2) trigger signaling to indicate whether the gap is for RLC, RRM, or both.

[0052] In another method, the UE 110 may be configured to first perform RLM on a non-anchor carrier based on CSI-RS. If a triggering condition for declaring radio link failure (RLF) occurs based on the RLM, the UE 110 may retune to the anchor carrier instead of declaring an RLF. In this method, the network (e.g., gNB) may decide how to handle the UE 110 after retuning to the anchor carrier. For example, the network may decide to hand over the UE 110 to a different anchor carrier or configure the UE 110 to use a different non-anchor carrier. In some embodiments, the UE 110 may perform RLM after retuning back to the anchor carrier and declare an RLF if triggered.

[0053] In yet another method, the UE 110 may be configured to perform RLM based on CSI-RS only on a non-anchor carrier. In this method, if the RLF triggering condition is met, the UE 110 may declare an RLF on the non-anchor carrier.

[0054] In addition, the UE 110 may perform beam failure detection (BFD) and beam failure recovery (BFR) on the anchor carrier together with the RRC connected mode RRM. In some embodiments, the same retuning gap may be used for BFD and for collecting measurement data for RLM and / or RRM. In other embodiments, at least one retuning gap may be configured for BFD, and at least one other retuning gap may be configured for RLM and / or RRM. For example, a first periodic retuning gap pattern may be configured for BFD, and a second different periodic retuning gap pattern may be configured for RRM and / or RLM. As another example, a single periodic measurement gap may be configured, where a subset of the retuning gap is configured for BFD, and a different subset of the retuning gap may be configured for RRM and / or RLM. Since BFD is performed on the anchor carrier, the UE 110 may trigger BFR on the anchor carrier.

[0055] In other embodiments, the UE 110 may be configured to perform BFD on a non-anchor carrier based on CSI-RS. If a trigger condition indicating BFD occurs, the UE 110 may retune to the anchor carrier to perform BFR. In other embodiments, the UE 110 may be configured to perform BFD on a non-anchor carrier based on CSI-RS. If a trigger condition indicating BFD occurs, the UE 110 may perform BFR on the non-anchor carrier.

[0056] In 425, the UE 110 enters the RRC idle mode or the RRC inactive mode and tunes to the anchor carrier. When the UE 110 operates in the RRC idle mode or the RRC inactive mode, the UE 110 may perform measurements only on the anchor carrier. Although not shown in method 400, the UE 110 may perform another RACH procedure to enter the RRC connected mode and be configured (or reconfigured) with one or more non-anchor carriers.

[0057] In some embodiments, the UE 110 performs a RACH procedure on the anchor carrier. This includes DCI-triggered RACH, MAC-triggered RACH, and RRC-triggered RACH. In some embodiments, the UE 110 may be indicated by the network via DCI or MAC CE to use a single retuning gap, or may be autonomously triggered to use a single retuning gap to perform RACH on the anchor carrier and then tune back to the non-anchor carrier.

[0058] In another method, the UE 110 may be configured to perform RACH on a non-anchored carrier based on CSI-RS transmitted on the non-anchored carrier. In yet another method, the UE 110 may be configured to perform RACH on a non-anchored carrier based on the SSB transmitted on the anchored carrier and the quasi-co-location (QCL) indication for the non-anchored carrier. QCL may be used to map the SSB measured on the anchored carrier and the associated RACH resources in the non-anchored carrier. QCL may be configured for each non-anchored carrier or may be common to all non-anchored carriers.

[0059] In addition, the exemplary embodiments introduce techniques for paging reception and transmission in a multi-carrier system configured to support an anchored carrier. In one method, the UE 110 may receive paging on the anchored carrier. For example, when in the RRC connected mode, the UE 110 may be configured with periodic retuning gaps to monitor paging on the anchored carrier.

[0060] In another method, the UE 110 may receive paging on a non-anchored carrier. The network may indicate to the UE 110 via RRC signaling or in any other suitable manner that the non-anchored carrier supports paging in the SIB. In addition, the network may provide QCL information to the UE 110 to indicate the beam information for paging transmission.

[0061] In some embodiments, on the network side, the gNB may perform filtering on the paging provided by the core network. For example, the access and mobility management function (AMF) may transmit paging to the gNB 120A for transmission to the connected UE. The gNB 120A may decide whether to forward it to the cell operating on the non-anchored carrier. In this example, for RAN paging, the gNB may not transmit paging to its cell operating on the non-anchored carrier.

[0062] In another method, the AMF may transmit the core network paging only to the gNBs having an anchored cell. Then, the gNB may forward the paging to the UE. In this example, for RAN paging, the AMF may not transmit paging to its cell operating on the non-anchored carrier.

[0063] Embodiment

[0064] In a first embodiment, a method performed by a user equipment (UE), the method includes performing initial access on an anchored carrier of a fifth generation (5G) new radio (NR) network and monitoring a non-anchored carrier for unicast transmission, wherein the non-anchored carrier does not broadcast a synchronization signal block (SSB).

[0065] In a second embodiment, the method according to the first embodiment, wherein the non-anchored carrier does not transmit a broadcast system information block (SIB).

[0066] In a third embodiment, according to the method of the first embodiment, the method further includes selecting, from a set of multiple non-anchor carriers, the non-anchor carrier to be used for transmission.

[0067] In a fourth embodiment, according to the method of the third embodiment, the method further includes receiving an indication from a base station of the 5G NR network, the indication indicating which non-anchor carrier to select from the set of multiple non-anchor carriers for transmission.

[0068] In a fifth embodiment, according to the method of the fourth embodiment, wherein the indication can be provided via layer 1 (L1), layer 2 (L2), or radio resource control (RRC).

[0069] In a sixth embodiment, according to the method of the first embodiment, wherein the UE is configured with a duration during which the UE tunes away from the non-anchor carrier and monitors the anchor carrier.

[0070] In a seventh embodiment, according to the method of the sixth embodiment, wherein the UE re-tunes to the non-anchor carrier after the expiration of the duration.

[0071] In an eighth embodiment, according to the method of the sixth embodiment, wherein the duration is one of a periodic pattern of durations during which the UE is configured to tune away from the non-anchor carrier and perform radio resource management (RRM) based on a synchronization signal block (SSB) transmitted by the anchor carrier, wherein the UE is further configured to re-tune to the non-anchor carrier after the duration.

[0072] In a ninth embodiment, according to the method of the sixth embodiment, wherein the duration is a single re-tuning gap during which the UE is configured to tune away from the non-anchor carrier and perform radio resource management (RRM) based on a synchronization signal block (SSB) transmitted by the anchor carrier, wherein the UE is further configured to re-tune to the non-anchor carrier after the duration.

[0073] In a tenth embodiment, according to the method of the ninth embodiment, wherein the single re-tuning gap is triggered by the network via a layer 1 (L1) or layer 2 (L2) signal.

[0074] In an eleventh embodiment, according to the method of the sixth embodiment, wherein the UE is autonomously triggered to tune away from the non-anchor carrier during the duration and perform radio resource management (RRM) based on a synchronization signal block (SSB) transmitted by the anchor carrier, and wherein the UE is further configured to re-tune to the non-anchor carrier after the duration.

[0075] In a twelfth embodiment, according to the method of the sixth embodiment, wherein the duration is configured via radio resource control (RRC) signaling.

[0076] In a thirteenth embodiment, according to the method of the first embodiment, the method further includes entering a radio resource control (RRC) connected mode, and when in the RRC connected mode and monitoring the non-anchor carrier, collecting measurement data based on a channel state information (CSI)-reference signal (RS) transmitted by the non-anchor carrier.

[0077] In a fourteenth embodiment, according to the method of the thirteenth embodiment, wherein an offset value is applied to the measurement data based on the CSI-RS to compensate for a difference between measurements performed on the CSI-RS transmitted by the non-anchor carrier and a signal synchronization block (SSB) transmitted by the anchor carrier.

[0078] In a fifteenth embodiment, according to the method of the fourteenth embodiment, wherein the offset is provided via radio resource control (RRC) and is dedicated to the non-anchor carrier or is common to multiple non-anchor carriers.

[0079] In a sixteenth embodiment, according to the method of the first embodiment, wherein the UE is configured to perform radio link monitoring (RLM) on a reference signal transmitted by the anchor carrier.

[0080] In a seventeenth embodiment, according to the method of the sixteenth embodiment, wherein the UE is configured with one or more re-tuning gaps during which the UE will tune away from the non-anchor carrier and perform radio link monitoring (RLM) based on an SSB transmitted by the anchor carrier, and wherein the UE is further configured to re-tune to the non-anchor carrier after the re-tuning gap.

[0081] In an eighteenth embodiment, according to the method of the seventeenth embodiment, wherein a first re-tuning gap is configured for RLM and a second re-tuning gap is configured for radio resource management (RRM).

[0082] In the nineteenth embodiment, according to the method of the eighteenth embodiment, wherein the first retuning gap and the second retuning gap are the same retuning gap.

[0083] In the twentieth embodiment, according to the method of the eighteenth embodiment, wherein the first retuning gap and the second retuning gap are different retuning gaps.

[0084] In the twenty - first embodiment, according to the method of the eighteenth embodiment, wherein the first retuning gap and the second retuning gap are different retuning gaps of the same periodic retuning gap pattern.

[0085] In the twenty - second embodiment, according to the method of the seventeenth embodiment, wherein the one or more retuning gaps are configured by the network via radio resource control signaling, the method further comprising receiving a layer 1 (L1) or layer 2 (L2) signal from the network, the signal indicating whether the retuning gap configured via RRC is for RLM or radio resource management (RRM).

[0086] In the twenty - third embodiment, according to the method of the first embodiment, wherein the UE is configured to perform radio link monitoring (RLM) on the non - anchored carrier based on channel state information (CSI) - reference signal (RS) transmitted by the non - anchored carrier.

[0087] In the twenty - fourth embodiment, according to the method of the twenty - third embodiment, the method further comprises identifying a radio link failure (RLF) condition on the non - anchored carrier based on the RLM; in response to identifying the RLF condition, detuning from the non - anchored carrier and monitoring the anchored carrier; and performing RLM on the anchored carrier.

[0088] In the twenty - fifth embodiment, according to the method of the twenty - third embodiment, the method further comprises declaring a radio link failure (RLF) on the non - anchored carrier based on the RLM.

[0089] In the twenty - sixth embodiment, according to the method of the first embodiment, the method further comprises performing beam failure detection (BFD) on the anchored carrier and performing beam failure recovery (BFR) on the anchored carrier.

[0090] In the twenty - seventh embodiment, according to the method of the first embodiment, the method further comprises performing beam failure detection (BFD) on the non - anchored carrier based on channel state information (CSI) - reference signal (RS) transmitted by the non - anchored carrier and performing beam failure recovery (BFR) on the anchored carrier.

[0091] In the twenty-eighth embodiment, according to the method of the first embodiment, the method further includes performing beam failure detection (BFD) on the non-anchored carrier based on channel state information (CSI)-reference signal (RS) transmitted by the non-anchored carrier and performing beam failure recovery (BFR) on the non-anchored carrier.

[0092] In the twenty-ninth embodiment, according to the method of the first embodiment, wherein the UE is configured to perform a random access channel (RACH) procedure on the anchored carrier.

[0093] In the thirtieth embodiment, according to the method of the twenty-ninth embodiment, the method further includes receiving a signal triggering the UE to use a retuning gap and perform the RACH procedure on the anchored carrier; and retuning to the non-anchored carrier after the RACH procedure.

[0094] In the thirty-first embodiment, according to the method of the first embodiment, wherein the UE is configured to perform a random access channel (RACH) procedure on the non-anchored carrier based on channel state information (CSI)-reference signal (RS) transmitted by the non-anchored carrier.

[0095] In the thirty-second embodiment, according to the method of the first embodiment, wherein the UE is configured to perform a random access channel (RACH) procedure on the non-anchored carrier based on a synchronization signal block (SSB) transmitted by the anchored carrier and a quasi-co-location (QCL) indication between the anchored carrier and the non-anchored carrier.

[0096] In the thirty-third embodiment, according to the method of the thirty-second embodiment, wherein the QCL indication maps the SSB transmitted by the anchored carrier and the associated RACH resources in the non-anchored carrier.

[0097] In the thirty-fourth embodiment, according to the method of the first embodiment, wherein the UE is configured to monitor paging from the anchored carrier during a retuning gap.

[0098] In the thirty-fifth embodiment, according to the method of the first embodiment, wherein the UE is configured to monitor paging on the non-anchored carrier.

[0099] In the thirty-sixth embodiment, according to the method of the thirty-fifth embodiment, the method further includes receiving quasi-co-location (QCL) information from the network, the QCL information corresponding to the beam to be used for paging transmission.

[0100] In the thirty-seventh embodiment, according to the method described in the first embodiment, the method further includes deriving timing information of the non-anchor carrier based on the slot timing and offset value of the anchor carrier.

[0101] In the thirty-eighth embodiment, according to the method described in the thirty-seventh embodiment, wherein the offset value is configured via radio resource control (RRC) signaling.

[0102] In the thirty-ninth embodiment, according to the method described in the thirty-eighth embodiment, wherein the offset value is configured on a per non-anchor carrier basis.

[0103] In the fortieth embodiment, according to the method described in the thirty-eighth embodiment, wherein the offset value is shared by a group of non-anchor carriers.

[0104] In the forty-first embodiment, according to the method described in the thirty-seventh embodiment, wherein the slot timing of the anchor carrier is derived based on a synchronization signal block (SSB) transmitted on the anchor carrier.

[0105] In the forty-second embodiment, according to the method described in the first embodiment, the method further includes estimating the path loss of the non-anchor carrier for uplink power control based on a synchronization signal block (SSB) transmitted on the anchor carrier and an offset value relative to the non-anchor carrier.

[0106] In the forty-third embodiment, according to the method described in the forty-second embodiment, wherein the offset value is configured on a per non-anchor carrier basis.

[0107] In the forty-fourth embodiment, according to the method described in the forty-second embodiment, wherein the offset value is shared by a group of non-anchor carriers.

[0108] In the forty-fifth embodiment, according to the method described in the first embodiment, the method further includes estimating the path loss of the non-anchor carrier for uplink power control based on a channel state information (CSI)-reference signal (RS) transmitted on the non-anchor carrier.

[0109] In the forty-sixth embodiment, a processor configured to execute any one of the methods described in the first embodiment to the forty-fifth embodiment.

[0110] In the forty-seventh embodiment, a user equipment (UE) comprising: a transceiver configured to communicate with a network; and a processor communicatively coupled to the transceiver and configured to execute any one of the methods described in the first embodiment to the forty-fifth embodiment.

[0111] Those skilled in the art will understand that the above-described exemplary embodiments can be implemented with any suitable software configuration or hardware configuration or a combination thereof. Exemplary hardware platforms for implementing the exemplary embodiments may include, for example, Intel x86-based platforms with compatible operating systems, Windows OS, Mac platforms and MAC OS, and mobile devices with operating systems such as iOS, Android, etc. Exemplary embodiments of the above methods can be embodied as programs containing lines of code stored on a non-transitory computer-readable storage medium, which, when compiled, can be executed on a processor or microprocessor.

[0112] Although this application describes various embodiments that each have different features in various combinations, those skilled in the art will understand that any feature of one embodiment can be combined with the features of other embodiments in any way that is not explicitly negated or that is not functionally or logically inconsistent with the operation of the device or the specified functions of the disclosed embodiments.

[0113] It is well known that the use of personally identifiable information should follow privacy policies and practices that are recognized as meeting or exceeding industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of inadvertent or unauthorized access or use, and the nature of the authorized use should be clearly explained to users.

[0114] It will be apparent to those skilled in the art that various modifications can be made to the present disclosure without departing from the essence or scope of the present disclosure. Therefore, it is intended that the present disclosure cover modifications and variations of the present disclosure as long as they come within the scope of the appended claims and their equivalents.

Claims

1. A device of a user equipment (UE), the device comprising processing circuitry configured to: Perform initial access on an anchor carrier of a fifth generation (5G) new radio (NR) network; and Monitor a non-anchor carrier for unicast transmission, wherein the non-anchor carrier does not broadcast a synchronization signal block (SSB).

2. The device according to claim 1, wherein the non-anchor carrier does not broadcast a system information block (SIB).

3. The device according to claim 1, wherein the processing circuitry is further configured to: Select the non-anchor carrier for transmission from a group of multiple non-anchor carriers.

4. The device according to claim 3, wherein the processing circuitry is further configured to: Decode an indication on which non-anchor carrier to select for transmission from the group of multiple non-anchor carriers based on a signal received from a base station of the 5G NR network.

5. The device according to claim 1, wherein the UE is configured with a duration during which the UE tunes away from the non-anchor carrier and monitors the anchor carrier.

6. The device according to claim 5, wherein the UE re-tunes to the non-anchor carrier after the duration expires.

7. The device according to claim 5, wherein the duration is one of a periodic pattern of durations during which the UE is configured to tune away from the non-anchor carrier and perform radio resource management (RRM) based on a synchronization signal block (SSB) transmitted by the anchor carrier, wherein the UE is further configured to re-tune to the non-anchor carrier after the duration.

8. The device according to claim 5, wherein the duration is a single re-tuning gap during which the UE is configured to tune away from the non-anchor carrier and perform radio resource management (RRM) based on a synchronization signal block (SSB) transmitted by the anchor carrier, wherein the UE is further configured to re-tune to the non-anchor carrier after the duration.

9. The device according to claim 5, wherein the UE is autonomously triggered to tune away from the non-anchor carrier during the duration and perform radio resource management (RRM) based on a synchronization signal block (SSB) transmitted by the anchor carrier, wherein the UE is further configured to re-tune to the non-anchor carrier after the duration.

10. The device according to claim 1, wherein the processing circuitry is further configured to: Enter a radio resource control (RRC) connected mode; and When in the RRC connected mode and monitoring the non-anchor carrier, collect measurement data based on a channel state information (CSI)-reference signal (RS) transmitted by the non-anchor carrier.

11. The apparatus according to claim 10, wherein an offset value is applied to the measurement data based on the CSI-RS to compensate for a difference between measurements performed on the CSI-RS transmitted by the non-anchored carrier and a signal synchronization block (SSB) transmitted by the anchored carrier.

12. The apparatus according to claim 1, wherein the UE is configured to perform radio link monitoring (RLM) on a reference signal transmitted by the anchored carrier.

13. The method according to claim 12, wherein the UE is configured with one or more retuning gaps, during which the UE tunes away from the non-anchored carrier and performs radio link monitoring (RLM) based on an SSB transmitted by the anchored carrier, and wherein the UE is further configured to retune to the non-anchored carrier after the retuning gap.

14. The apparatus according to claim 13, wherein a first retuning gap is configured for RLM and a second retuning gap is configured for radio resource management (RRM).

15. The apparatus according to claim 14, wherein the first retuning gap and the second retuning gap comprise (i) the same retuning gap, (ii) different retuning gaps, or (iii) different retuning gaps of the same periodic retuning gap pattern.

16. The apparatus according to claim 13, wherein the one or more retuning gaps are configured by the network via radio resource control signaling, and wherein the processing circuit is further configured to: decode a layer 1 (L1) or layer 2 (L2) signal indicating whether a retuning gap configured via RRC will be used for RLM or radio resource management (RRM) based on a signal received from the network.

17. The apparatus according to claim 1, wherein the UE is configured to perform radio link monitoring (RLM) on the non-anchored carrier based on a channel state information (CSI)-reference signal (RS) transmitted by the non-anchored carrier.

18. The apparatus according to claim 17, wherein the processing circuit is further configured to: identify a radio link failure (RLF) condition on the non-anchored carrier based on the RLM; tune away from the non-anchored carrier and monitor the anchored carrier in response to identifying the RLF condition; and perform RLM on the anchored carrier.

19. The apparatus according to claim 17, wherein the processing circuit is further configured to: declare a radio link failure (RLF) on the non-anchored carrier based on the RLM.

20. The apparatus according to claim 1, wherein the processing circuit is further configured to: perform beam failure detection (BFD) on the anchored carrier; and perform beam failure recovery (BFR) on the anchored carrier.

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