Systems and methods for cell radio network temporary identifier use in wireless communication systems

Abstract

Systems and methods for cell-less wireless communication architectures are described. In some embodiments, a user equipment (UE) receives, from a transmission reception point (TRP) of a radio access network (RAN), a full cell radio network temporary identifier (C-RNTI) that identifies the UE within the RAN and a shortened C-RNTI that (also) identifies the UE within the RAN. Use cases for each of the full C-RNTI and the shortened C-RNTI are described. In some embodiments, a UE receives, from a master TRP of a RAN, a first synchronization signal and system information comprising a PRACH configuration for a first assistant TRP of the RAN; receives, from the first assistant TRP, a synchronization signal; identifies a PRACH configuration for the first assistant TRP from the system information received from the master TRP; and performs a RACH procedure with the first assistant TRP using the PRACH configuration for the first assistant TRP.

Description

SYSTEMS AND METHODS FOR CELL RADIO NETWORK TEMPORARYIDENTIFIER USE IN WIRELESS COMMUNICATION SYSTEMSTECHNICAL FIELD

[0001] This application relates generally to wireless communication systems, including wireless communications systems using cell-less architectures.BACKGROUND

[0002] Wireless mobile communication technology uses various standards and protocols to transmit data between a base station and a wireless communication device. Wireless communication system standards and protocols can include, for example. 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) (e.g., 4G), 3GPP New Radio (NR) (e.g., 5G), and Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard for Wireless Local Area Networks (WLAN) (commonly known to industry groups as Wi-Fi®).

[0003] As contemplated by the 3GPP, different wireless communication systems' standards and protocols can use various radio access networks (RANs) for communicating between a base station of the RAN (which may also sometimes be referred to generally as a RAN node, a network node, or simply a node) and a wireless communication device known as a user equipment (UE). 3GPP RANs can include, for example, Global System for Mobile communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE) RAN (GERAN), Universal Terrestrial Radio Access Network (UTRAN). Evolved Universal Terrestrial Radio Access Network (E-UTRAN), and / or Next-Generation Radio Access Network (NG-RAN).

[0004] Each RAN may use one or more radio access technologies (RATs) to perform communication between the base station and the UE. For example, the GERAN implements GSM and / or EDGE RAT, the UTRAN implements Universal Mobile Telecommunication System (UMTS) RAT or other 3GPP RAT, the E-UTRAN implements LTE RAT (sometimes simply referred to as LTE), and NG-RAN implements NR RAT (sometimes referred to herein as 5G RAT, 5G NR RAT, or simply NR). In certain deployments, the E-UTRAN may also implement NR RAT. In certain deployments, NG-RAN may also implement LTE RAT.

[0005] A base station used by a RAN may correspond to that RAN. One example of an E-UTRAN base station is an Evolved Universal Terrestrial Radio Access Network (E- UTRAN) Node B (also commonly denoted as evolved Node B, enhanced Node B, eNodeB, or eNB). One example of an NG-RAN base station is a next generation Node B (also sometimes referred to as a g Node B or gNB).

[0006] A RAN provides its communication services with external entities through its connection to a core network (CN). For example, E-UTRAN may utilize an Evolved Packet Core (EPC) while NG-RAN may utilize a 5G Core Network (5GC).

[0007] Frequency bands for 5G NR may be separated into two or more different frequency ranges. For example, Frequency Range 1 (FR1) may include frequency bands operating in sub-6 gigahertz (GHz) frequencies, some of which are bands that may be used by previous standards, and may potentially be extended to cover new spectrum offerings from 410 megahertz (MHz) to 7125 MHz. Frequency Range 2 (FR2) may include frequency bands from 24.25 GHz to 52.6 GHz. Note that in some systems, FR2 may also include frequency bands from 52.6 GHz to 71 GHz (or beyond). Bands in the millimeter wave (mmWave) range of FR2 may have smaller coverage but potentially higher available bandwidth than bands in FR1. Skilled persons will recognize these frequency ranges, which are provided by way of example, may change from time to time or from region to region.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0008] To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the figure number in which that element is first introduced.

[0009] FIG. 1 illustrates a graph of spectral efficiency achievable by a UE on a cell with respect to a position of a UE relative to a TRP of the cell being used by the UE in two dimensions.

[0010] FIG. 2 illustrates a network topology that may be used in a wireless communication system.

[0011] FIG. 3 illustrates a network topology of a wireless communication system that uses CoMP.

[0012] FIG. 4 illustrates a diagram of a UE that operates with a first TRP and a second TRP in an mTRP mode.

[0013] FIG. 5 illustrates a network topology corresponding to a cell-less architecture for wireless communication systems, according to embodiments discussed herein.

[0014] FIG. 6 illustrates a diagram of a cell-less architecture, according to embodiments discussed herein.

[0015] FIG. 7 illustrates a diagram corresponding to initial access of UEs to the network in a cell-less architecture, according to embodiments discussed herein.

[0016] FIG. 8 illustrates a method of an initial access procedure in a cell-less architecture, according to embodiments herein.

[0017] FIG. 9 illustrates a diagram corresponding to initial access of UEs to the network in a cell-less architecture, according to embodiments discussed herein.

[0018] FIG. 10 illustrates a diagram corresponding to the use of an S SB as a top QCL source of a master TRP, according to embodiments discussed herein.

[0019] FIG. 11 illustrates a diagram corresponding to the use of a CSI-RS as a top QCL source of an assisting TRP, according to embodiments discussed herein.

[0020] FIG. 12 illustrates a diagram corresponding to coverage of UEs by the network in a heterogeneous cell-less architecture, according to embodiments discussed herein.

[0021] FIG. 13 illustrates a diagram corresponding to initial access of UEs to the network in a heterogeneous cell-less architecture, according to embodiments discussed herein.

[0022] FIG. 14 illustrates a method of a UE in wireless communication with a RAN, according to embodiments discussed herein.

[0023] FIG. 15 illustrates a method of a TRP of a RAN, according to embodiments discussed herein.

[0024] FIG. 16 illustrates a method of a UE, according to embodiments discussed herein.

[0025] FIG. 17 illustrates a method of a RAN, according to embodiments discussed herein.

[0026] FIG. 18 illustrates an example architecture of a wireless communication system, according to embodiments disclosed herein.

[0027] FIG. 19 illustrates a sy stem for performing signaling between a wireless device and a network device, according to embodiments disclosed herein.DETAILED DESCRIPTION

[0028] Various embodiments are described with regard to a UE. However, reference to a UE is merely provided for illustrative purposes. The example embodiments may be utilized with any electronic component that may establish a connection to a network and is configured with the hardware, software, and / or firmware to exchange information and data with the network. Therefore, the UE as described herein is used to represent any appropriate electronic component.

[0029] FIG. 1 illustrates a graph 100 of spectral efficiency 102 achievable by a UE on a cell with respect to a position 104 of a UE relative to a transmission reception point (TRP) of the cell being used by the UE in two dimensions. The two spatial dimensions exist in the x-y plane of the graph 100, while spectral efficiency 102 is found in the z- axis (as illustrated). The graph 100 corresponds to the case where the TRP of the cell is located at position (250, 250).

[0030] The graph 100 illustrates that the effects 106 of pathloss experienced by the UE on the spectral efficiency 102 become more pronounced as the UE moves away from the TRP and thus toward the cell edge 1 8. As illustrated, this may be because, for large cells, the spectral efficiency 102 is limited by noise at the cell edge 108, while for small cells, the spectral efficiency 102 is limited by interference at the cell edge 108.

[0031] In various real-world situations, it may be observed that most active users are at a cell edge. Because of the obstacles at the cell edge 108 as described, there may be unsatisfactory performance at a UE that is at the cell edge 108, even in the case of NR communications. For example, in some cases, communication speeds with the UE at the cell edge 108 may be less than 1 megabit per second (Mbps) in uplink (UL). In some contexts, it may be that a target for UL speeds may be higher than this (e.g., some NR wireless communications systems may be intended to target communication speeds of 10 Mbps in downlink (DL) and at least 1 Mbps in UL (e.g., when using FR1 and at least for urban scenarios)).

[0032] In wireless communications systems according to some cellular architectures, each UE in the wireless communication system connects to one transmission reception point (TRP). In such cases, it may be understood that the (single) TRP provides coverage to the UE using a cell of / served by the TRP. Some such cellular architectures provide relatively higher peak data rates toward the cell center (e.g., toward the serving TRP),but experience large quality variations across the entire cell as the UE moves away from the serving TRP.

[0033] FIG. 2 illustrates a network topology 200 that may be used in a wireless communication system. The network topology 200 includes various TRPs 202 (only one is labelled in FIG. 2) that provide coverage through one or more cells 204 (only one is labelled in FIG. 2), as illustrated. Various UEs 206 in the region are thereby each served by the network through one of the cells 204 of one of the TRPs 202, as illustrated.

[0034] In some cases, network densification may be employed. Network densification provides an increase in TRP density in a geographic area, such that, in general, a probability' that a UE is relatively nearer a TRP (than it would otherwise be without the netw ork densification) is increased. In an ideal case, a capacity' of the netw ork would accordingly grow proportionally to the increase in the number of TRPs. However, the use of network densification increases the general amount of inter-cell interference that occurs, such that any benefit gained by continually adding more TRPs within the geographic area under consideration tapers off.

[0035] With respect to some wireless communication systems (e.g., wireless communications systems implementing E-UTRAN), some mechanisms for multi-cell cooperation to provide coverage to a single UE may be referred to under the umbrella term “coordinated multi-point’" (CoMP). A wireless communication system may use CoMP to enable cooperation between neighboring TRPs (e.g., a “CoMP cooperating set’" of TRPs) that work together to provide coverage to UE(s) in a manner that reduces intercell interference as compared to cases where CoMP is not used.

[0036] FIG. 3 illustrates a network topology 300 of a wireless communication system that uses CoMP. The network topology 300 includes a first CoMP cooperating set 302 made up of first TRPs 304 that use a CoMP mechanism to serve a first UE 306, a second CoMP cooperating set 308 made up of second TRPs 310 that use a CoMP mechanism to serve a second UE 312, and a third CoMP cooperating set 314 made up of third TRPs 316 that use a CoMP mechanism to serve a third UE 318. In some cases, the use of cooperation between TRPs may be limited to cooperation between TRPs in the same CoMP cooperating set 302, 308, 314.

[0037] Various CoMP mechanisms may implement one or more of joint transmission (JT) (either coherent JT (CJT) or non-coherent JT (NCJT)), dynamic point selection,coordinated scheduling and / or beamforming, and / or some combination of these categories.

[0038] Some wireless communications systems implement multiple TRP (mTRP) mechanisms. In some systems using such mTRP mechanisms, a UE may send and / or receive data to and / or from multiple TRPs.

[0039] FIG. 4 illustrates a diagram 400 of a UE 402 that operates with a first TRP 404 and a second TRP 406 in an mTRP mode. The diagram 400 illustrates a case of a multidownlink control information (DCI) (multi-DCI) mode of mTRP used by the UE 402, where the UE 402 is configured to receive and use each of a first DCI 408 from the first TRP 404 and a second DCI 410 from the second TRP 406. As illustrated, the UE may further be configured to accordingly receive and use each of a first physical downlink shared channel (PDCSH) 412 corresponding to a first transmission configuration indicator (TCI) ("TCI1") (e.g., as scheduled by the first DCI 408) and a second PDSCH 414 corresponding to a second TCI ("TCI1") (e g., as scheduled by the second DCI 410).

[0040] In some wireless communication systems, an mTRP mechanism may be based on / assume a cell-based network architecture. Further, the number / limit of cooperating TRPs may be limited in such cases. In such cases, there may be no use of, for example, a definition of a TRP identifier (ID) at a physical layer (PHY). Finally, in such cases, TRPs may be differentiated by beam IDs.Table 1 : Evolution of 5G mTRP Mechanisms in 3GPP

[0041] Table 1 relates an evolution of 5G mTRP mechanisms in 3GPP wireless communication systems. As shown, Release 15 ("R15") 3GPP wireless communication systems may use transparent transmission operations and a small number of TRPs.

[0042] Release 16 ("R16") 3GPP wireless communications systems may use intra-cell mTRP NCJT. Further, in the case of the use of a single DCI, R1 systems may use spatial division multiplexing (SDM), frequency division multiplexing (FDM), and / or time domain multiplexing (TDM), and one TCI codepoint in a DCI may be mapped to up to two TCI states. In the case that multi-DCI is used, R16 systems may use a control resource set (CORESET) pool index to differentiate two TRPs, and an mTRP PDSCH may be fully, partially, and / or non-overlapped in a time and / or frequency domain.

[0043] Release 17 ("R17") 3GPP wireless communication systems may use inter-cell mTRP NCJT. In such cases, a radio resource control (RRC) mechanism may configure synchronization signal block (SSB) information for neighbor cells. Further, the mTRP NCJT mechanisms may be based on an R16 based multi-DCI framework.

[0044] R17 wireless communication systems may use various mTRP beam management enhancements that may not be present in earlier releases. These may include the abi 1 i ty to use a group based beam report (e.g., of up to four beams) and the use of two channel measurement resource (CMR) resource sets.

[0045] Release 18 ("R18") 3GPP wireless communication systems may use channel state information (CSI) acquisition for CJT targeting FR1 (e g., for up to four TRPs). In such a scenario, refined Type II codebooks and / or enhanced sounding reference signals (SRSs) may be used. Further, it may be that R18 systems leverage various TCI framework extensions into mTRP use cases.

[0046] Various aspects of quasi-colocation (QCL) and SSB operation as may be understood with respect to some 5G NR wireless communications systems are now described. In such wireless communication systems, there may various roles for an SSB. For example, the SSB may be used to broadcast synchronization signals and system information, may be used for beam management, may be used as a QCL source of PHY channels and signals, and / or may be used to perform radio resource management (RRM) measurements. In some NR systems, there may be up to 64 SSB candidates that can be shared amongst all beams and TRPs.

[0047] Various aspects of initial access and RRM measurement as may be understood with respect to some 5G NR wireless communication systems are now described. Within such systems, initial access may be achieved via blindly decoding an SSB. Through this process, the UE acquires a physical cell identity (PCI), an SSB index, and a master information block (MIB). A combination of a primary synchronization signal (PSS) and secondary synchronization signal (SSS) may help to identify one out of the 1008 PCIs. Then, the UE may receive and decode a system information block (SIB) 1 (SIB1).During random access, a physical random access channel (PRACH) occasion of sending Message 1 is associated with SSB index. A cell radio network temporary identifier (C- RNTI) (e.g., that is 16-bits) is unique within a cell. Further, major use cases of C-RNTI may include, addressing a UE when making resource allocation, and identifying a UE and its associated UE context information during handover.

[0048] Within RRM measurement, an SSB and / or a channel state information reference signal (CSI-RS) may be configured as measurement resources. Then, in some wireless communication systems, cell and / or beam level measurement results may be reported from the UE to the network.

[0049] With respect to improving wireless communication system technology, one goal is to alleviate the cell-edge problem (e.g., as discussed above in relation to FIG. 1) on a larger scale. Another way of stating this goal may be to cause a UE to experience cellcenter aspects more frequently, while reducing the frequency of later (upon moving) experiencing cell-boundary aspects.

[0050] Existing solutions for wireless communication systems support cell-less MIMO concepts to only a partial extent and are not scalable in large-scale network scenarios. For example, 3GPP R16 and R17 5G NR focus on NCJT using two TRPs, while R18 5G NR contemplates CJT using four TRPs. The simple extension of these embodiments tolarge numbers of cooperating TRPs would result in mechanisms that are inefficient in terms of signaling and procedure. Further, in various existing 5G NR systems, the number of SSB candidates is up to 64, which are shared by all TRPs and beams. This number of SSBs becomes insufficient as a number TRPs becomes large when extending existing 5G NR concepts. In view of these aspects, it may be understood that existing 5G NR SSB design presupposes mainly co-located MIMO systems.

[0051] Moreover, when contemplating an increase of average number of TRPs serving each UE, it is observed that from a mobility perspective, a latency and / or interruptions caused by correspondingly frequent handover (e.g.. as understood in 5G NR) may be unsatisfactory corresponding to small-area-coverage scenarios.

[0052] Based on at least these examples, it may be concluded that issues with incorporating massively distributed MIMO into existing systems ultimately lies in the fact that the existing systems are based on cell-based network architecture assumptions. Accordingly, the present disclosure targets scalable and cost-effective implementations of cell-less network architectures. In some cases, such cell-less network architectures may be referred to as “cell-free multiple input multiple output (MIMO),” “massively distributed MIMO,” and / or “user-centric RAN.”

[0053] FIG. 5 illustrates a network topology 500 corresponding to a cell-less architecture for wireless communication systems, according to embodiments discussed herein. The network topology 500 illustrates various UEs (the first UE 502, the second UE 504, and the third UE 506). The first UE is served in a cell-less manner by a first cluster 508 of TRPs that includes a first TRP 514, a second TRP 516, a third TRP 518, and a fourth TRP 520. The second UE 504 is served in a cell-less manner by a second cluster 510 of TRPs that includes the third TRP 518, the fourth TRP 520, a fifth TRP 522, and a sixth TRP 524. The third UE 506 is served in a cell-less manner by a third cluster 512 of TRPs that includes the fifth TRP 522, the sixth TRP 524, and a seventh TRP 526.

[0054] Systems and methods disclosed herein enable efficient and scalable cell-less network architectures. These systems and methods may represent examples of “6G” 3GPP architectures. For example, embodiments discussed herein relate to mechanisms and procedures to enable cell-less architecture through a UE awareness of TRPs. Further, embodiments discussed herein relate initial access aspects in cell-less architectures. Further, embodiments discussed herein relate to heterogeneous cell-less architectures.Finally, embodiments discussed herein relate to RRM measurement aspects assuming cell-less architectures.

[0055] Embodiments discussed herein related to such systems and methods may provide one or more of various possible benefits. For example, embodiments discussed herein may be scalable with a potentially large number of TRPs using JT. due to the use of a heterogeneous cell-less architecture. Further, embodiments discussed herein may provide seamless mobility at the UE, as cell changes may be transparent to UE while the UE is in the RRC connected state. Further, embodiments discussed herein may enable reduced power consumption in the wireless communication system and / or the UE, at least since only a small number (or at least fewer than all) of the TRPs in the system may be used to broadcast common information used at UEs for initial acquisition / access. Finally, embodiments discussed herein may provide improved over-the-air resource utilization, again since only a small number (or at least fewer than all) of the TRPs in the system may be used to broadcast common information used at UEs for initial acquisition.Embodiments of Cell-less Architecture in RRC Connected State

[0056] Mechanisms and procedures discussed herein enable the use of a cell-less architecture through UE awareness of TRPs. In some such cases, from the UE's perspective, there may be no notion of a cell when the UE is in an RRC connected state. Rather, the UE is served by a group of TRPs defined as cluster. TRPs belonging to one cluster can be from the same or different cells, as such cells are understood from the network perspective.

[0057] In some cases, it may not be necessary for each TRP to cover the entire cell. Further, a UE may be aware of a change of its serving TRPs without necessarily knowing that it has experienced a change of cell, as the cell may be understood by the network.

[0058] In such circumstances, it may be that UE-specific PHY channel and / or signal configurations are independent of cell ID.

[0059] FIG. 6 illustrates a diagram 600 of a cell-less architecture, according to embodiments discussed herein. The diagram 600 illustrates that a RAN operates a centralized unit (CU) 602 that controls a first distributed unit (DU) 604 operating a first cell 606 from the network perspective and a second DU 608 operating a second cell 610 from the network perspective. As shown, the first cell 606 includes a first TRP 612, asecond TRP 614, a third TRP 616, and a fourth TRP 618, while the second cell 610 includes the fifth TRP 620, the sixth TRP 622, and the seventh TRP 624.

[0060] As illustrated in this example, at a first time, a UE 626 is served by a first cluster 628 that contains the first TRP 612, the second TRP 614, and the third TRP 616. The UE 626 relies on this first cluster 628 for such service and does not rely on any concept of an underlying cell (e.g., the first cell 606) for such service.

[0061] The UE then moves 630 such that it is at another location within the coverage area of the wireless communication system at a second time. At this second time, the UE 626 is served by a second cluster 632 that contains the fourth TRP 618, the fifth TRP 620, and the sixth TRP 622. The UE 626 relies on this second cluster 632 for such service at this second time and does not rely on any concept of an underlying cell (e.g., either the first cell 606 and / or the second cell 610) for such service. Note that the second cluster 632 as used by the UE illustrates the concept of cross-cell clustering, as it includes one or more TRPs from each of the first cell 606 (the fourth TRP 618) and the second cell 610 (the fifth TRP 620, and the sixth TRP 622) as these cells are understood from a network perspective.

[0062] Further, in this example, the UE 626 is not aware of any formal cell change between the first time and the second time. Thus, latency and / or the potential for service interruption corresponding to the mobility of the UE 626 within the wireless communication system are reduced.Initial Access Concepts in Cell-Less Architecture

[0063] A cell concept may be leveraged with respect to RRC idle and / or RRC inactive states at the UE. It may be that in network implementation, there is a single cell per carrier per DU. Accordingly, in general, the physical size of a cell may be much larger as compared to cells in other wireless communications systems (e.g.. as compared to a 5G NR cell). Thus, even though the coverage provided by a single TRP may be relatively small, the overall cell coverage may be large (since the cell includes a large number of TRPs).

[0064] In some embodiments proposed / discussed herein, it may be that a subset of TRPs (e.g., rather than all TRPs) broadcasts both synchronization signals and common information for use with UE initial acquisition (while the remaining TRPs may broadcast synchronization signals but not common information). The common informationbroadcast by this subset of TRPs may include common system information that applies to / is about one or more TRPs in the wireless communication system.

[0065] In a first such alternative, TRP IDs may be transmitted (either implicitly or explicitly) in or alongside the common information. Accordingly, messages from different TRPs in the system may be the same except for the TRP ID. Accordingly, if the UE receives a message from multiple TRPs, it may need to decode each message separately (thus, the UE acquires the TRP ID via decoding common information). In some such cases, PRACH occasions are associated with TRP IDs, or jointly with TRP IDs and SSB indexes. Note that in some cases, a TRP ID is an identifier that is uniquely used to identify the TRP. In other cases a TRP ID may be a virtual ID represented by another value corresponding to the TRP, such as a synchronization signal ID of a synchronization signal broadcast by the TRP, a beam ID of a beam used at the TRP, a CSI-RS (set) ID of a CSI-RS set used by the TRP, etc.

[0066] In a second such alternative, no TRP ID is transmitted in or along with common information. In such cases, messages from different TRPs may therefore be identical. If the UE receives a message from multiple TRPs, the UE may be in a single frequency network (SFN) mode.

[0067] Embodiments herein contemplate that common information as broadcast by a TRP (e.g., that includes common system information) contains a list of neighboring TRPs. In this way, a UE is informed of its surrounding TRPs (e.g., possible future TRPs). For example, the list of neighboring TRPs may be contained in an SIB received by the UE.Embodiments with Respect to C-RNTI

[0068] In some existing wireless communication systems (e.g., 5G NR wireless communication systems), a C-RNTI of a UE is uniquely assigned within a cell (there are no two UE in the same cell using the same C-RNTI). A C-RNTI may have a 16-bit length identify representation, with the value thereof ranging from 1 to 65519.

[0069] There are at least two use cases of C-RNTI in wireless communication systems. In a first use case, the C-RNTI is used to address a UE within the system when making resource allocations. In a second use, the C-RNTI is used to identify' a UE and its associated UE context information during a handover procedure.

[0070] When a cell size becomes large, a C-RNTI length of 16 bits may not provide enough unique values for each of the UEs in the UE set of the cell. Further, if the number of bits for a C-RNTI is correspondingly enlarged, signaling overhead and UE decoding complexity burdens are increased.

[0071] The at least two use cases of C-RNTI discussed above have different requirements. For example, in the case of resource allocation addressing, a C-RNTI can be reused by two (or more) UEs in a cell, as long as these UEs are far enough away from each other such that they cannot both receive a same resource allocation transmission using that C-RNTI. On the other hand, with respect to UE identification during handover, a C-RNTI should be unique within a cell to avoid confusion.

[0072] Embodiments herein discuss the use of two ty pes of C-RNTI: a full C-RNTI with an A -bit length, and a shortened C-RNTI with a ?-bit length, where A > B. In some such cases, a shortened C-RNTI of a UE may be a truncated version of the full C-RNTI for the UE (e g., the least significant B bits of the .4 -bit full C-RNTI). The two ty pes of C-RNTI may each be assigned to a UE during a random access channel (RACE!) procedure between a TRP of the network and the UE.

[0073] The full C-RNTI of a UE may be uniquely used by that UE within the cell. However, the shortened C-RNTI of the UE is not understood to necessarily also have this property. Embodiments discussed herein contemplate that a shortened C-RNTI can be reused within a cell, as long as there is no collision / confusion among UEs of the cell. For example, when two UEs are served by different TRPs that are far away from each other, the two UEs can be assigned with / use the same shortened C-RNTI.

[0074] The full C-RNTI may thus be used for handover (where unique C-RNTI references should be used), while a shortened C-RNTI can be used for addressing purposes for UE communication resource allocation in a physical downlink control channel (PDCCH) from the network (where uniqueness concerns as between two distant UE within the same cell are not strict, as described above). Thus, overhead for C-RNTI use (at least in the resource allocation case) may be relatively reduced as compared to the case where a unique C-RNTI is otherwise used for both circumstances.

[0075] Within such constructs, it may be that, due to UE movement, originally assigned shortened C-RNTIs may become collided locally. Accordingly, embodiments herein contemplate that the base station can configure a new shortened C-RNTI to a UE (and, for example, without necessarily changing the UE's full C-RNTI).

[0076] In embodiments discussed herein, a mapping between shortened C-RNTIs and the corresponding full C-RNTI may be maintained at either and / or both of the base station and / or the UE.Embodiments with Respect to Initial Access

[0077] FIG. 7 illustrates a diagram 700 corresponding to initial access of UEs 702, 704 to the network in a cell-less architecture, according to embodiments discussed herein. The diagram 700 illustrates that a RAN operates a CU 706 that controls a first DU 708 operating a first cell 712 from the network perspective and a second DU 710 operating a second cell 714 from the network perspective. As shown, the first cell 712 includes a first TRP 716, a second TRP 718, a third TRP 720, and a fourth TRP 722, while the second cell 714 includes the fifth TRP 724, the sixth TRP 726, the seventh TRP 728, and the eighth TRP 730.

[0078] In various embodiments, it may be that a subset of the TRPs is broadcasting common information for purposes of UE initial access (as opposed to all TRPs broadcasting such common information). For example, as illustrated in FIG. 7, it may be that the first TRP 716, the third TRP 720, the sixth TRP 726, and the eighth TRP 730 broadcast common information while the second TRP 718, the fourth TRP 722, the fifth TRP 724, and the seventh TRP 728 do not broadcast common information.

[0079] In the case illustrated in FIG. 7. a first UE 702 receives common information as broadcast by the first TRP 716 and the third TRP 720, and the second UE 704 receives common information from the sixth TRP 726 (each of the first UE 702 and the second UE 704 is out of range of the common information as broadcast by the eighth TRP 730).

[0080] In a case where the common information as broadcast by a TRP arrives with or alongside a TRP ID of the broadcasting TRP (e.g., as described elsewhere herein), the first UE 702 uses the received broadcasts from the first TRP 716 and the third TRP 720 to acquire the TRP IDs of each of the first TRP 716 and the third TRP 720. and the second UE 704 uses the received broadcast from the sixth TRP 726 to acquire the TRP ID of the sixth TRP 726

[0081] The common information provided to the first UE 702 and the second UE 704 may further include remaining minimum system information (RMSI) such as, for example, a SIB that contains scheduling information for a RACH procedure to use to connect to the broadcasting TRP. This enables each / either of the first UE 702 and thesecond UE 704 to initiate PRACH using the corresponding PRACH occasions for the TRPs (which may be associated jointly with TRP IDs and SSB indexes). Further, during such RACH process(es), each / either of the first UE 702 and the second UE 704 may be assigned with both full C-RNTI and shortened C-RNTI (as has been described). Further, as a result of such RACH process(es), each / either of the first UE 702 and the second UE 704 may become RRC-connected.

[0082] In some embodiments contemplated herein, a subset of all of the TRPs within the network may broadcast synchronization signals, but not common system information. As contemplated with respect to this disclosure, ‘"synchronization signals” should be interpreted in a general sense. For example, a PSS and / or an SSS as defined in 5G NR are examples of synchronization signals, but other formats for synchronizations signals are possible / may be used. Power consumption by TRPs that broadcast synchronization signals without also broadcasting common system information may be reduced with respect to TRPs that broadcast both synchronization signals and common system information.

[0083] In various embodiments, it is contemplated that a TRP ID for a TRP may be provided in / with a synchronization signal transmitted by that TRP. Thus, after detecting a synchronization signal, a UE also knows an associated TRP ID for a TRP that broadcasts that synchronization signal.

[0084] FIG. 8 illustrates a method 800 of an initial access procedure in a cell-less architecture, according to embodiments herein. First, a subset A of TRPs broadcast 802 both synchronization signals and common information for UE initial acquisition. The common information includes common system information. Further, another subset B of TRPs broadcasts 804 synchronization signals but not common information. Note that for all TRPs, the UE may acquire a corresponding TRP ID using the detected corresponding synchronization signal.

[0085] Then, based on the received signals, the UE obtains 806 measurements for different TRPs. Depending on the measurement results (e.g., depending on a strongest measurement), the UE determines 808 whether or not to connect to a TRP that is in the subset A. If the UE determines 808 not to connect to a TRP that is in subset A, then the UE performs 810 a RACH procedure with and connects to the TRP belonging to subset B. In such circumstances, associated PRACH occasions can be inferred by applying the TRP ID for the synchronization signal received from the selected TRP of set B withsystem information for that TRP as was received from a broadcast of common information of a TRP of subsets.

[0086] If the UE instead determines 808 to connect to a TRP that is in subset A, then the UE performs 812 a RACH procedure with and connects to the TRP belonging to subsets.

[0087] Embodiments disclosed herein may be of interest in cases where, for example, an amount of traffic to / from a UE is small. In such cases, it may be beneficial to have that UE connect to a TRP located in the UE?s local area that is broadcasting synchronization signals but not common information. This may result in power / energy saving for the UE and / or the network.

[0088] FIG. 9 illustrates a diagram 900 corresponding to initial access of UEs 902, 904 to the network in a cell-less architecture, according to embodiments discussed herein. The diagram 900 illustrates that a RAN operates a CU 906 that controls a first DU 908 operating a first cell 912 from the network perspective and a second DU 910 operating a second cell 914 from the network perspective. As shown, the first cell 912 includes a first TRP 916. a second TRP 918, a third TRP 920. and a fourth TRP 922, while the second cell 914 includes the fifth TRP 924, the sixth TRP 926, the seventh TRP 928, and the eighth TRP 930.

[0089] In the diagram 900, the first TRP 916, the third TRP 920. the sixth TRP 926 and the eighth TRP 930 are “full-functional” TRPs that broadcast information for UE initial acquisition including both synchronization signals and common information (e.g., that includes common system information). On the other hand, the second TRP 918, the fourth TRP 922. the fifth TRP 924, and the seventh TRP 928 are “light” TRPs that broadcast synchronization signals but do not broadcast common information.

[0090] As illustrated, the first UE 902 receives both synchronization signals and common information (common system information) from the first TRP 916 and synchronization signals (but not common information) from second TRP 918. The first UE 902 measures that a reference signal received power (RSRP) of second TRP 918 is larger than an RSRP of first TRP 916. Accordingly, the first UE 902 connects to second TRP 918 via a RACH procedure (based on system information for the second TRP 918 as was provided in common information received from the first TRP 916).

[0091] Further, the second UE 904 receives both synchronization signals and common information (e.g., that includes common system information) from sixth TRP 926 andsynchronization signals (but not common information) from fifth TRP 924. The second UE 904 measures that an RSRP of sixth TRP 926 is larger than an RSRP of fifth TRP 924. Accordingly, the second UE 904 and connects to the sixth TRP 926 via a RACH procedure (based on system information for the sixth TRP 926 as was provided in common information from the sixth TRP 926).Heterogeneous Cell-Less Architecture Details

[0092] One use case / motivation for the use of mTRP transmission mechanisms is to increase data rates between a network and a UE. It is not necessary that all TRPs broadcast common information given its small pay load. On the other hand, JT through multiple TRPs may be used for applications with demanding data rate requirements.

[0093] Hence, it may be beneficial to divide TRPs of a wireless communication system into two categories, for example, master TRPs and assisting TRPs. The broadcast of common information is the responsibility of master TRPs. Assisting TRPs are used to boost data rates, and may in some cases only be enabled when needed.

[0094] With respect to master TRPs, it may be that each cell includes one or multiple master TRPs (e.g., at least one master TRP), each of which broadcasts information used for UE initial acquisition (e.g., broadcasts both a synchronization signal and common information). A lower layer ID (e.g.. a PHY ID or TRP ID) is assigned to each master TRP. This TRP ID can be reused as long as there is no collision / confusion within the wireless communication system (e g., two TRPs that are far away from each other can be assigned with the same TRP ID - this may be referred to as a TRP (ID) reuse factor). PRACH occasions may be associated with master TRP IDs, or jointly with master TRP IDs and SSB indexes. A master TRP may be involved in data transmission to a UE when the UE is in an RRC connected state.

[0095] Assisting TRPs, on the other hand, may not broadcast the full set of information for UE initial acquisition (e.g., while an assisting TRP may broadcast a synchronization signal, it may not also broadcast common information). An assisting TRP may be active / activated when / as needed. Note that in some cases, an assisting TRP is not necessarily associated with an SSB as its top QCL source. Rather, it may be that an assisting TRP can have synchronization signals or CSI-RS as its top QCL source.

[0096] FIG. 10 illustrates a diagram 1000 corresponding to the use of an SSB 1002 as a top QCL source 1004 of a master TRP, according to embodiments discussed herein. TheSSB 1002 may be made up of the synchronization signal 1006 and the MIB 1008 in some embodiments. As illustrated, the master TRP may broadcast the SSB 1002 (e.g., on a periodic basis) for use by the UE.

[0097] FIG. 11 illustrates a diagram 1100 corresponding to the use of a CSI-RS 1102 as a top QCL source 1104 of an assisting TRP. according to embodiments discussed herein. As illustrated, the assisting TRP may broadcast CSI-RSs 1102 (e.g., on a periodic bases) for use by the UE.

[0098] It may be noted that if the heterogeneous cell-less architecture is mapped to the initial access framework discussed earlier herein, a master TRP may be interpreted as a “full-functional” TRP (a TRP that broadcasts synchronization signals and common information) while an assisting TRP may be interpreted as a “light” TRP (a TRP that broadcasts synchronization signals without also broadcasting common information).

[0099] FIG. 12 illustrates a diagram 1200 corresponding to coverage of UEs 1202, 1204 by the network in a heterogeneous cell-less architecture, according to embodiments discussed herein. The diagram 1200 illustrates that a RAN operates a CU 1206 that controls a first DU 1208 operating a first cell 1212 from the network perspective and a second DU 1210 operating a second cell 1214 from the network perspective. As shown, the first cell 1212 includes a first master TRP 1216, a first assisting TRP 1218, a second master TRP 1220, and a second assisting TRP 1222, while the second cell 1214 includes the third assisting TRP 1224. the third master TRP 1226. the and the fourth assisting TRP 1228.

[0100] In the example illustrated in FIG. 12, the first UE 1202 is served through a first cluster 628 that includes the first master TRP 1216, the first assisting TRP 1218. and the second master TRP 1220. Among other things, this illustrates that a cluster that serves a UE may use fewer than all of the TRPs that are in a cell as understood from the network perspective.

[0101] FIG. 12 further illustrates that the second UE 1204 is served through a second cluster 632 that includes the second assisting TRP 1222 and the third assisting TRP 1224. Among other things, this illustrates that a cluster that serves a UE is not required to include a master TRP. For example, it may be that while a master TRP (e.g.. the third master TRP 1226) may have initially provided the second UE 1204 with common information (e.g., that includes common system information), that common information was used by the second UE 1204 to form, in conjunction with the network, the secondcluster 632 that does not actually include any master TRPs. This may be the case when, for example, measurements of synchronization signals from each of the second assisting TRP 1222, the third assisting TRP 1224, and the third master TRP 1226 inform the UE that the second assisting TRP 1222 and the third assisting TRP 1224 are associated with acceptable coverage characteristics (e.g., acceptable RSRPs) but that the third master TRP 1226 is not associated with acceptable coverage characteristics (even if it was the source of the system information used to identify the second assisting TRP 1222 and the third assisting TRP 1224 to the UE).

[0102] The use by the second UE 1204 of the second cluster 632 also illustrates that a cluster can be made up of TRPs from multiple different cells as understood from the network perspective.

[0103] FIG. 13 illustrates a diagram 1300 corresponding to initial access of UEs to the network in a heterogeneous cell-less architecture, according to embodiments discussed herein. The diagram 1300 illustrates that a RAN operates a CU 1302 that controls a first DU 1304 operating a first cell 1308 from the network perspective and a second DU 1306 operating a second cell 1310 from the network perspective. As shown, the first cell 1308 includes a first master TRP 1312, a first assisting TRP 1314. a second master TRP 1316, and a second assisting TRP 1318, while the second cell 1310 includes the third assisting TRP 1320, the third master TRP 1322, the and the fourth assisting TRP 1324.

[0104] The diagram 1300 illustrates that master TRPs (the first master TRP 1312, the second master TRP 1316, and the third master TRP 1322) within the wireless communication system broadcast (e.g., in addition to synchronization signals) common information (e.g., that includes common system information). It is contemplated that in some embodiments, common information as broadcast by master TRPs may further include or arrive alongside a master TRP ID for the broadcasting master TRP. For example, as illustrated in FIG. 13, the first master TRP 1312 broadcasts first common information 1326 that includes or arrives alongside a first TRP ID 1332 for the first master TRP 1312, the second master TRP 1316 broadcasts second common information 1328 that includes or arrives alongside a second TRP ID 1334 for the second master TRP 1316, and the third master TRP 1322 broadcasts third common information 1330 that includes or arrives alongside a third TRP ID 1336 for the third master TRP 1322.

[0105] Network resource use within a heterogeneous cell-less architecture is now discussed. As an example, consider a case where there are A TRPs in total in a wirelesscommunication system, where Y such TRPs are master TRPs (and thus X-Y of the TRPs are assisting TRPs). Assume also in this case that different TRPs use different timefrequency resources for an SSB broadcast. Then, the proposed heterogeneous architecture (where assisting TRPs do not broadcast SSBs) may be understood to save (X-Y) * 960 * 50 * c resource elements (REs) per second in the case of a 20 millisecond (ms) SSB periodicity (where c is a number of SSBs within a 5 ms window (which can be up to 64 in 5G NR). 50 is a number of the 20 ms SSB periodicities within one second, and 960 is the number of occupied REs per SSB (corresponding to 20 resource blocks (RBs) over 4 orthogonal frequency division multiplexing (OFDM) symbols)). Then, so long as resources synchronization signals used by the assisting TRPs are fewer than this amount, network resource savings are achieved (given the same parameter configuration, e.g., SSB periodicity).

[0106] Within the cell-less architectures disclosed herein, it may be that either / both of TRP-level and / or beam-level measurements are performed by a UE and reported by the UE to the network. In such circumstances, it is contemplated that a measurement report may include a relevant TRP ID and / or beam ID.

[0107] As the UE may not have any concept of a cell, there may be no use of cell-level measurements and / or corresponding cell-level measurement reporting. It is further noted that a TRP-level measurement report is not supported in 5G NR.

[0108] In some embodiments, it may be that a base station configures to a UE the manner of deriving any TRP-level measurements that are taken and / or reported. For example, the base station may configure to the UE that TRP-level measurements are to be derived from beam-level measurements by taking the average of a number N of best beams of the TRP. In the context of, for example, a heterogeneous cell-less architecture, measurements related to master TRPs may be performed using SSBs, while measurements related to assisting TRPs may be performed using synchronization signals and / or CSl-RSs.

[0109] A measurement report so derived may be sent to the network through any TRP in the UE's cluster / any TRP through which the UE connects to the network (whether a master TRP or an assistant TRP). Note further that there is no requirement that the measurement report be sent to the network through a TRP that is reported-on and / or thatuses beams that are reported-on in the measurement report (in other words, a TRP of the UE's cluster that is not reported-on in the measurement report and / or that does not use any reported-on beams from the measurement report may be used for delivery of the measurement report to the network).

[0110] In the present disclosure, a set of embodiments to enable scalable and efficient implementation of cell-free MIMO / massively distributed MIMO / user-centric RAN are provided. At least some embodiments describe mechanisms and procedures to enable cell-less architecture through a UE awareness of TRPs. At least some embodiments relate to UE initial access in a cell-less architecture. At least some embodiments relate to the use of a heterogeneous cell-less architecture. At least some embodiments relate to RRM measurement aspects within a cell-less architecture.

[0111] Various benefits may be achieved with respect to embodiments disclosed herein. These include scalability, with a potentially large number of TRPs operating under joint transmission principles; seamless mobility, where a UE is not required perform a formal / traditional handover between (e.g., primary) serving cells; reduced power consumption at either / both the UE and the network side; and / or improved over-the-air resource utilization within the wireless communication system.

[0112] FIG. 14 illustrates a method 1400 of a UE in wireless communication with a RAN, according to embodiments discussed herein. The method 1400 includes receiving 1402, from a TRP of the RAN. a first synchronization signal and system information comprising a PRACH configuration for the TRP. The method 1400 further includes performing 1404 a RACK procedure with the TRP using the PRACH configuration for the TRP, wherein performing the RACH procedure comprises receiving, from the TRP, a full C-RNTI that identifies the UE within the RAN and a shortened C-RNTI that identifies the UE within the RAN.

[0113] In some embodiments, the method 1400 further includes receiving a PDCCH transmission that schedules a communication resource of the RAN to the UE, wherein the PDCCH transmission identifies the UE based on the shortened C-RNTI; and performing network communication with the RAN using the communication resource.

[0114] In some embodiments, the method 1400 further includes storing, at the UE, an association between the full C-RNTI and the shortened C-RNTI.

[0115] In some embodiments of the method 1400, the full C-RNTI is of a first bit length that is longer than a second bit length of the shortened C-RNTI.

[0116] In some embodiments, the method 1400 further includes receiving a replacement shortened C-RNTI that identifies the UE within the RAN; and replacing the shortened C- RNTI with the replacement shortened C-RNTI.

[0117] FIG. 15 illustrates a method 1500 of a TRP of a RAN, according to embodiments discussed herein. The method 1500 includes broadcasting 1502 a first synchronization signal and system information comprising a PRACH configuration for the TRP. The method 1500 further includes performing 1504 a RACH procedure with a UE of the RAN according to the PRACH configuration for the TRP, wherein the performing the RACH procedure comprises sending, to the UE, a full C-RNTI that identifies the UE within the RAN and a shortened C-RNTI that identifies the UE within the RAN.

[0118] In some embodiments, the method 1500 further includes sending a PDCCH transmission that schedules a communication resource of the RAN to the UE, wherein the PDCCH transmission identifies the UE based on the shortened C-RNTI.

[0119] In some embodiments, the method 1500 further includes performing network communication with the UE using the communication resource.

[0120] In some embodiments, the method 1500 further includes storing, at the TRP, an association between the full C-RNTI and the shortened C-RNTI.

[0121] In some embodiments of the method 1500, the full C-RNTI is of a first bit length that is longer than a second bit length of the shortened C-RNTI.

[0122] In some embodiments, the method 1500 further includes sending, to the UE, a replacement shortened C-RNTI that identifies the UE within the RAN.

[0123] FIG. 16 illustrates a method 1600 of a UE. according to embodiments discussed herein. The method 1600 includes receiving 1602, from a master TRP of a RAN, a first synchronization signal and common system information comprising a PRACH configuration for a first assistant TRP of the RAN. The method 1600 further includes receiving 1604, from the first assistant TRP, a second synchronization signal comprising a TRP ID of the assistant TRP. The method 1600 further includes identifying 1606 the PRACH configuration for the first assistant TRP from the common system information received from the master TRP using the TRP ID of the first assistant TRP. The method 1600 further includes performing 1608 a RACH procedure with the first assistant TRP using the PRACH configuration for the first assistant TRP.

[0124] In some embodiments, the method 1600 further includes performing a measurement of the second synchronization signal from the first assistant TRP; and determining to connect to the first assistant TRP based on a result of the measurement.

[0125] In some embodiments, the method 1600 further includes performing a measurement of the first synchronization signal from the master TRP: and determining to connect to the master TRP based on a result of the measurement.

[0126] In some embodiments of the method 1600, the common system information further includes configuration information for connecting to a second assistant TRP; and the method 1600 further includes receiving, from the first assistant TRP, an instruction to connect to the second assistant TRP; and connecting, based on the instruction from the first assistant TRP, to the second assistant TRP according to the configuration information for the second assistant TRP.

[0127] In some embodiments of the method 1600, performing the RACH procedure with the first assistant TRP comprises receiving, from the first assistant TRP, a full C- RNTI that identifies the UE within the RAN and a shortened C-RNTI that identifies the UE within the RAN.

[0128] In some embodiments, the method 1600 further includes sending, to the first assistant TRP, a measurement report comprising TRP-level measurements of the first assistant TRP.

[0129] In some embodiments, the method 1600 further includes sending, to the first assistant TRP, a measurement report comprising TRP-level measurements of the master TRP.

[0130] In some embodiments, the method 1600 further includes sending, to the first assistant TRP, a measurement report comprising TRP-level measurements of a second assistant TRP.

[0131] FIG. 17 illustrates a method 1700 of a RAN, according to embodiments discussed herein. The method 1700 includes broadcasting 1702, through a first master TRP of the RAN, a first synchronization signal and common system information comprising a PRACH configuration for a first assistant TRP of the RAN. The method 1700 further includes broadcasting 1704, from the first assistant TRP, a second synchronization signal comprising a first TRP ID of the first assistant TRP. The method 1700 further includes performing 1706, using the first assistant TRP, a RACFI procedure with a UE using the PRACH configuration for the first assistant TRP.

[0132] In some embodiments, the method 1700 further includes broadcasting, through a second master TRP of the RAN, a second TRP ID of the second master TRP. wherein the second TRP ID of the second master TRP is also used by the first master TRP.

[0133] In some embodiments, the method 1700 further includes receiving, at the first assistant TRP. from the UE, a measurement report comprising TRP-level measurements of the first assistant TRP.

[0134] In some embodiments, the method 1700 further includes receiving, at the first assistant TRP. from the UE, a measurement report comprising TRP-level measurements of the first master TRP.

[0135] In some embodiments, the method 1700 further includes receiving, at the first assistant TRP. from the UE, a measurement report comprising TRP-level measurements of a second assistant TRP.

[0136] FIG. 18 illustrates an example architecture of a wireless communication system 1800, according to embodiments disclosed herein. The following description is provided for an example wireless communication system 1800 that operates in conjunction with the LTE system standards and / or 5G or NR system standards as provided by 3 GPP technical specifications.

[0137] As shown by FIG. 18, the wireless communication system 1800 includes UE 1802 and UE 1804 (although any number of UEs may be used). In this example, the UE 1802 and the UE 1804 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks), but may also comprise any mobile or non-mobile computing device configured for wireless communication.

[0138] The UE 1802 and UE 1804 may be configured to communicatively couple with a RAN 1806. In embodiments, the RAN 1806 may be NG-RAN. E-UTRAN, etc. The UE 1802 and UE 1804 utilize connections (or channels) (shown as connection 1808 and connection 1810, respectively) with the RAN 1806, each of which comprises a physical communications interface. The RAN 1806 can include one or more base stations (such as base station 1812 and base station 1814) that enable the connection 1808 and connection 1810.

[0139] In this example, the connection 1808 and connection 1810 are air interfaces to enable such communicative coupling, and may be consistent with RAT(s) used by the RAN 1806, such as. for example, an LTE and / or NR.

[0140] In some embodiments, the UE 1802 and UE 1804 may also directly exchange communication data via a sidelink interface 1816. The UE 1804 is shown to be configured to access an access point (shown as AP 1818) via connection 1820. By way of example, the connection 1820 can comprise a local wireless connection, such as a connection consistent with any IEEE 802.11 protocol, wherein the AP 1818 may comprise a Wi-Fi® router. In this example, the AP 1818 may be connected to another network (for example, the Internet) without going through a CN 1824.

[0141] In embodiments, the UE 1802 and UE 1804 can be configured to communicate using OFDM communication signals with each other or with the base station 1812 and / or the base station 1814 over a multicarrier communication channel in accordance with various communication techniques, such as, but not limited to, an orthogonal frequency division multiple access (OFDMA) communication technique (e.g., for downlink communications) or a single carrier frequency division multiple access (SC-FDMA) communication technique (e.g., for uplink and ProSe or sidelink communications), although the scope of the embodiments is not limited in this respect. The OFDM signals can comprise a plurality' of orthogonal subcarriers.

[0142] In some embodiments, all or parts of the base station 1812 or base station 1814 may be implemented as one or more software entities running on server computers as part of a virtual network. In addition, or in other embodiments, the base station 1812 or base station 1814 may be configured to communicate with one another via interface 1822. In embodiments where the wireless communication system 1800 is an LTE system (e.g.. when the CN 1824 is an EPC), the interface 1822 may be an X2 interface. The X2 interface may be defined between two or more base stations (e.g., two or more eNBs and the like) that connect to an EPC, and / or between two eNBs connecting to the EPC. In embodiments where the wireless communication system 1800 is an NR system (e.g.. when CN 1824 is a 5GC), the interface 1822 may be an Xn interface. The Xn interface is defined between two or more base stations (e.g., two or more gNBs and the like) that connect to 5GC, between a base station 1812 (e.g., a gNB) connecting to 5GC and an eNB, and / or between two eNBs connecting to 5GC (e.g., CN 1824).

[0143] The RAN 1806 is shown to be communicatively coupled to the CN 1824. The CN 1824 may comprise one or more network elements 1826, which are configured to offer various data and telecommunications services to customers / subscribers (e.g., users of UE 1802 and UE 1804) who are connected to the CN 1824 via the RAN 1806. Thecomponents of the CN 1824 may be implemented in one physical device or separate physical devices including components to read and execute instructions from a machine- readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium).

[0144] In embodiments, the CN 1824 may be an EPC, and the RAN 1806 may be connected with the CN 1824 via an SI interface 1828. In embodiments, the SI interface 1828 may be split into two parts, an SI user plane (Sl-U) interface, which carries traffic data between the base station 1812 or base station 1814 and a serving gateway (S-GW), and the SI -MME interface, which is a signaling interface between the base station 1812 or base station 1814 and mobility management entities (MMEs).

[0145] In embodiments, the CN 1824 may be a 5GC, and the RAN 1806 may be connected with the CN 1824 via an NG interface 1828. In embodiments, the NG interface 1828 may be split into two parts, an NG user plane (NG-U) interface, which carries traffic data between the base station 1812 or base station 1814 and a user plane function (UPF), and the SI control plane (NG-C) interface, which is a signaling interface between the base station 1812 or base station 1814 and access and mobility management functions (AMFs).

[0146] Generally, an application server 1830 may be an element offering applications that use internet protocol (IP) bearer resources with the CN 1824 (e g., packet switched data services). The application server 1830 can also be configured to support one or more communication services (e.g., VoIP sessions, group communication sessions, etc.) for the UE 1802 and UE 1804 via the CN 1824. The application server 1830 may communicate with the CN 1824 through an IP communications interface 1832.

[0147] FIG. 19 illustrates a system 1900 for performing signaling 1934 between a wireless device 1902 and a network device 1918, according to embodiments disclosed herein. The system 1900 may be a portion of a wireless communications system as herein described. The wireless device 1902 may be, for example, a UE of a wireless communication system. The network device 1918 may be, for example, a base station (e.g., an eNB or a gNB) of a wireless communication system.

[0148] The wireless device 1902 may include one or more processor(s) 1904. The processor(s) 1904 may execute instructions such that various operations of the wireless device 1902 are performed, as described herein. The processor(s) 1904 may include one or more baseband processors implemented using, for example, a central processing unit(CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

[0149] The wireless device 1902 may include a memory 1906. The memory 1906 may be a non -transitory computer-readable storage medium that stores instructions 1908 (which may include, for example, the instructions being executed by the processor(s) 1904). The instructions 1908 may also be referred to as program code or a computer program. The memory 1906 may also store data used by. and results computed by, the processor(s) 1904.

[0150] The wireless device 1902 may include one or more transceiver(s) 1910 that may include radio frequency (RF) transmitter circuitry and / or receiver circuitry that use the antenna(s) 1912 of the wireless device 1902 to facilitate signaling (e.g.. the signaling 1934) to and / or from the wireless device 1902 with other devices (e.g., the network device 1918) according to corresponding RATs.

[0151] The wireless device 1902 may include one or more antenna(s) 1912 (e.g., one, two, four, or more). For embodiments with multiple antenna(s) 1912, the wireless device 1902 may leverage the spatial diversity7of such multiple antenna(s) 1912 to send and / or receive multiple different data streams on the same time and frequency resources. This behavior may be referred to as. for example, MIMO behavior (referring to the multiple antennas used at each of a transmitting device and a receiving device that enable this aspect). MIMO transmissions by the wireless device 1902 may be accomplished according to precoding (or digital beamforming) that is applied at the wireless device 1902 that multiplexes the data streams across the antenna(s) 1912 according to known or assumed channel characteristics such that each data stream is received with an appropriate signal strength relative to other streams and at a desired location in the spatial domain (e.g., the location of a receiver associated with that data stream). Certain embodiments may use single user MIMO (SU-MIMO) methods (where the data streams are all directed to a single receiver) and / or multi user MIMO (MU-MIMO) methods (where individual data streams may be directed to individual (different) receivers in different locations in the spatial domain).

[0152] In certain embodiments having multiple antennas, the wireless device 1902 may implement analog beamforming techniques, whereby phases of the signals sent by theantenna(s) 1912 are relatively adjusted such that the (joint) transmission of the antenna(s) 1912 can be directed (this is sometimes referred to as beam steering).

[0153] The wireless device 1902 may include one or more interface(s) 1914. The interface(s) 1914 may be used to provide input to or output from the wireless device 1902. For example, a wireless device 1902 that is a UE may include interface(s) 1914 such as microphones, speakers, a touchscreen, buttons, and the like in order to allow for input and / or output to the UE by a user of the UE. Other interfaces of such a UE may be made up of transmitters, receivers, and other circuitry (e.g., other than the transceiver(s) 1910 / antenna(s) 1912 already described) that allow for communication between the UE and other devices and may operate according to known protocols (e.g., Wi-Fi®, Bluetooth®, and the like).

[0154] The wireless device 1902 may include a cell-less operation module 1916. The cell-less operation module 1916 may be implemented via hardware, software, or combinations thereof. For example, the cell-less operation module 1916 may be implemented as a processor, circuit, and / or instructions 1908 stored in the memory' 1906 and executed by the processor(s) 1904. In some examples, the cell-less operation module 1916 may be integrated within the processor(s) 1904 and / or the transceiver(s) 1910. For example, the cell-less operation module 1916 may be implemented by a combination of software components (e.g., executed by a DSP or a general processor) and hardware components (e.g., logic gates and circuitry ) within the processor(s) 1904 or the transceiver(s) 1910.

[0155] The cell-less operation module 1916 may be used for various aspects of the present disclosure, for example, aspects of FIG. 5 through FIG. 17. The cell-less operation module 1916 may configure the wireless device 1902 to, for example, receive and use both of a full C-RNTI and a shortened C-RNTI, as described herein.Additionally or alternatively, the cell-less operation module 1916 may configure the wireless device 1902 to, for example, use system information received from a master TRP and a synchronization signal from an assistant TRP that does not broadcast system information to perform a RACH procedure with the assistant TRP, as described herein.

[0156] The network device 1918 may include one or more processor(s) 1920. The processor(s) 1920 may execute instructions such that various operations of the network device 1918 are performed, as described herein. The processor(s) 1920 may include one or more baseband processors implemented using, for example, a CPU, a DSP, an ASIC, acontroller, an FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

[0157] The network device 1918 may include a memory 1922. The memory 1922 may be a non-transitory computer-readable storage medium that stores instructions 1924 (which may include, for example, the instructions being executed by the processor(s) 1920). The instructions 1924 may also be referred to as program code or a computer program. The memory 1922 may also store data used by, and results computed by, the processor(s) 1920.

[0158] The network device 1918 may include one or more transceiver(s) 1926 that may include RF transmitter circuitry and / or receiver circuitry that use the antenna(s) 1928 of the network device 1918 to facilitate signaling (e.g., the signaling 1934) to and / or from the network device 1918 with other devices (e.g., the wireless device 1902) according to corresponding RATs.

[0159] The network device 1918 may include one or more antenna(s) 1928 (e.g., one, two, four, or more). In embodiments having multiple antenna(s) 1928, the network device 1918 may perform M1M0, digital beamforming, analog beamforming, beam steering, etc., as has been described.

[0160] The network device 1918 may include one or more interface(s) 1930. The interface(s) 1930 may be used to provide input to or output from the network device 1918. For example, a network device 1918 that is a base station may include interface(s) 1930 made up of transmitters, receivers, and other circuitry (e.g., other than the transceiver(s) 1926 / antenna(s) 1928 already described) that enables the base station to communicate with other equipment in a core network, and / or that enables the base station to communicate with external networks, computers, databases, and the like for purposes of operations, administration, and maintenance of the base station or other equipment operably connected thereto.

[0161] The network device 1918 may include a cell-less operation module 1932. The cell-less operation module 1932 may be implemented via hardware, software, or combinations thereof. For example, the cell-less operation module 1932 may be implemented as a processor, circuit, and / or instructions 1924 stored in the memory 1922 and executed by the processor(s) 1920. In some examples, the cell-less operation module 1932 may be integrated within the processor(s) 1920 and / or the transceiver(s) 1926. For example, the cell-less operation module 1932 may be implemented by a combination ofsoftware components (e.g., executed by a DSP or a general processor) and hardware components (e.g., logic gates and circuitry) within the processor(s) 1920 or the transceiver(s) 1926.

[0162] The cell-less operation module 1932 may be used for various aspects of the present disclosure, for example, aspects of FIG. 5 through FIG. 17. The cell-less operation module 1932 may configure the network device 1918 to, for example, configure a UE with both of a full C-RNTI and a shortened C-RNTI, and use either of the full C-RNTI and / or the shortened C-RNTI to address the UE, as described herein. Additionally or alternatively, the cell-less operation module 1916 may configure the network device 1918 to, for example, broadcast system information by a master TRP and a synchronization signal from an assistant TRP that does not broadcast system information to perform a RACH procedure with the assistant TRP, such that a UE is enabled to use the system information from the master TRP to connect perform a RACH procedure with the assistant TRP on the basis of the synchronization signal from the assistant TRP, as described herein.

[0163] Embodiments contemplated herein include an apparatus comprising means to perform one or more elements of any one or more of the method 1400 and the method 1600. This apparatus may be, for example, an apparatus of a UE (such as a wireless device 1902 that is a UE, as described herein).

[0164] Embodiments contemplated herein include one or more non -transitory computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of any one or more of the method 1400 and the method 1600. This non-transitory computer-readable media may be, for example, a memory of a UE (such as a memory 1906 of a wireless device 1902 that is a UE, as described herein).

[0165] Embodiments contemplated herein include an apparatus comprising logic, modules, or circuitry to perform one or more elements of any one or more of the method 1400 and the method 1600. This apparatus may be, for example, an apparatus of a UE (such as a wireless device 1902 that is a UE, as described herein).

[0166] Embodiments contemplated herein include an apparatus comprising: one or more processors and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform one or more elements of any one or more of the method 1400 and the method1600. This apparatus may be. for example, an apparatus of a UE (such as a wireless device 1902 that is a UE, as described herein).

[0167] Embodiments contemplated herein include a signal as described in or related to one or more elements of any one or more of the method 1400 and the method 1600.

[0168] Embodiments contemplated herein include a computer program or computer program product comprising instructions, wherein execution of the program by a processor is to cause the processor to carry' out one or more elements of any one or more of the method 1400 and the method 1600. The processor may be a processor of a UE (such as a processor(s) 1904 of a wireless device 1902 that is a UE, as described herein). These instructions may be, for example, located in the processor and / or on a memory of the UE (such as a memory' 1906 of a wireless device 1902 that is a UE, as described herein).

[0169] Embodiments contemplated herein include an apparatus comprising means to perform one or more elements of the method 1500. This apparatus may be, for example, an apparatus of a TRP (such as a network device 1918 that is a TRP, as described herein).

[0170] Embodiments contemplated herein include one or more non -transitory computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of the method 1500. This non-transitory computer- readable media may be, for example, a memory' of a TRP (such as a memory 1922 of a network device 1918 that is a TRP, as described herein).

[0171] Embodiments contemplated herein include an apparatus comprising logic, modules, or circuitry7to perform one or more elements of the method 1500. This apparatus may be, for example, an apparatus of a TRP (such as a network device 1918 that is a TRP, as described herein).

[0172] Embodiments contemplated herein include an apparatus comprising: one or more processors and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform one or more elements of the method 1500. This apparatus may be, for example, an apparatus of a TRP (such as a network device 1918 that is a TRP, as described herein).

[0173] Embodiments contemplated herein include a signal as described in or related to one or more elements of the method 1500.

[0174] Embodiments contemplated herein include a computer program or computer program product comprising instructions, wherein execution of the program by a processing element is to cause the processing element to carry out one or more elements of the method 1500. The processor may be a processor of a TRP (such as a processor(s) 1920 of a network device 1918 that is a TRP, as described herein). These instructions may be, for example, located in the processor and / or on a memory of the TRP (such as a memory 1922 of a network device 1918 that is a TRP, as described herein).

[0175] Embodiments contemplated herein include an apparatus comprising means to perform one or more elements of the method 1700. This apparatus may be, for example, an apparatus of a base station (such as a network device 1918 that is a base station, as described herein).

[0176] Embodiments contemplated herein include one or more non -transitory computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of the method 1700. This non-transitory computer- readable media may be, for example, a memory of a base station (such as a memory 1922 of a network device 1918 that is a base station, as described herein).

[0177] Embodiments contemplated herein include an apparatus comprising logic, modules, or circuitry7to perform one or more elements of the method 1700. This apparatus may be, for example, an apparatus of a base station (such as a network device 1918 that is a base station, as described herein).

[0178] Embodiments contemplated herein include an apparatus comprising: one or more processors and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform one or more elements of the method 1700. This apparatus may be, for example, an apparatus of a base station (such as a network device 1918 that is a base station, as described herein).

[0179] Embodiments contemplated herein include a signal as described in or related to one or more elements of the method 1700.

[0180] Embodiments contemplated herein include a computer program or computer program product comprising instructions, wherein execution of the program by aprocessing element is to cause the processing element to carry out one or more elements of the method 1700. The processor may be a processor of a base station (such as a processor(s) 1920 of a network device 1918 that is a base station, as described herein). These instructions may be, for example, located in the processor and / or on a memory of the base station (such as a memory 1922 of a network device 1918 that a base station, as described herein).

[0181] For one or more embodiments, at least one of the components set forth in one or more of the preceding figures may be configured to perform one or more operations, techniques, processes, and / or methods as set forth herein. For example, a baseband processor as described herein in connection with one or more of the preceding figures may be configured to operate in accordance with one or more of the examples set forth herein. For another example, circuitry associated with a UE, base station, network element, etc. as described above in connection with one or more of the preceding figures may be configured to operate in accordance with one or more of the examples set forth herein.

[0182] Any of the above described embodiments may be combined with any other embodiment (or combination of embodiments), unless explicitly stated otherwise. The foregoing description of one or more implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of embodiments to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of various embodiments.

[0183] Embodiments and implementations of the systems and methods described herein may include various operations, which may be embodied in machine-executable instructions to be executed by a computer system. A computer system may include one or more general-purpose or special-purpose computers (or other electronic devices). The computer system may include hardware components that include specific logic for performing the operations or may include a combination of hardware, software, and / or firm are.

[0184] It should be recognized that the systems described herein include descriptions of specific embodiments. These embodiments can be combined into single systems, partially combined into other systems, split into multiple systems or divided or combined in other ways. In addition, it is contemplated that parameters, attributes, aspects, etc. of one embodiment can be used in another embodiment. The parameters, attributes, aspects,etc. are merely described in one or more embodiments for clarity', and it is recognized that the parameters, attributes, aspects, etc. can be combined with or substituted for parameters, attributes, aspects, etc. of another embodiment unless specifically disclaimed herein.

[0185] It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users.

[0186] Although the foregoing has been described in some detail for purposes of clarity, it will be apparent that certain changes and modifications may be made without departing from the principles thereof. It should be noted that there are many alternative ways of implementing both the processes and apparatuses described herein. Accordingly, the present embodiments are to be considered illustrative and not restrictive, and the description is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.

Claims

CLAIMS1. A method of a user equipment (UE) in wireless communication with a radio access network (RAN), comprising: receiving, from a transmission reception point (TRP) of the RAN, a first synchronization signal and system information comprising a physical random access channel (PRACH) configuration for the TRP; and performing a random access channel (RACH) procedure with the TRP using the PRACH configuration for the TRP, wherein the performing the RACH procedure comprises receiving, from the TRP, a full cell radio network temporary identifier (C- RNTI) that identifies the UE within the RAN and a shortened C-RNTI that identifies the UE within the RAN.

2. The method of claim 1, further comprising: receiving a physical downlink control channel (PDCCH) transmission that schedules a communication resource of the RAN to the UE, wherein the PDCCH transmission identifies the UE based on the shortened C-RNTI; and performing network communication with the RAN using the communication resource.

3. The method of claim 1, further comprising storing, at the UE, an association between the full C-RNTI and the shortened C-RNTI.

4. The method of claim 1, wherein the full C-RNTI is of a first bit length that is longer than a second bit length of the shortened C-RNTI.

5. The method of claim 1, further comprising: receiving a replacement shortened C-RNTI that identifies the UE within the RAN; and replacing the shortened C-RNTI with the replacement shortened C-RNTI.

6. A method of a transmission reception point (TRP) of a radio access network (RAN), comprising: broadcasting a first synchronization signal and system information comprising a physical random-access channel (PRACH) configuration for the TRP; andperforming a random access channel (RACH) procedure with a user equipment (UE) of the RAN according to the PRACH configuration for the TRP, wherein the performing the RACH procedure comprises sending, to the UE, a full cell radio network temporary identifier (C-RNTI) that identifies the UE within the RAN and a shortened C- RNTI that identifies the UE within the RAN.

7. The method of claim 6, further comprising sending a physical downlink control channel (PDCCH) transmission that schedules a communication resource of the RAN to the UE, wherein the PDCCH transmission identifies the UE based on the shortened C- RNTI.

8. The method of claim 7, further comprising performing network communication with the UE using the communication resource.

9. The method of claim 6, further comprising storing, at the TRP, an association between the full C-RNTI and the shortened C-RNTI.

10. The method of claim 6, wherein the full C-RNTI is of a first bit length that is longer than a second bit length of the shortened C-RNTI.

11. The method of claim 6, further comprising sending, to the UE, a replacement shortened C-RNTI that identifies the UE within the RAN.

12. An apparatus comprising means to perform the method of any of claim 1 to claim 11.

13. A computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform the method of any of claim 1 to claim 11.

14. An apparatus comprising logic, modules, or circuitry to perform the method of any of claim 1 to claim 11.

15. An apparatus of a user equipment (UE) for use for wireless communication w ith a radio access network (RAN), comprising: one or more processors; and a memory storing instructions that, when executed by the one or more processors, configure the UE to:receive, from a transmission reception point (TRP) of the RAN, a first synchronization signal and system information comprising a physical random access channel (PRACH) configuration for the TRP; and perform a random access channel (RACH) procedure with the TRP using the PRACH configuration for the TRP, wherein the performing the RACH procedure comprises receiving, from the TRP, a full cell radio network temporaryidentifier (C-RNTI) that identifies the UE within the RAN and a shortened C- RNTI that identifies the UE within the RAN.

16. An apparatus of a transmission reception point (TRP) of a radio access network (RAN), comprising: one or more processors; and a memory storing instructions that, when executed by the one or more processors, configure the TRP to: broadcast a first synchronization signal and system information comprising a physical random access channel (PRACH) configuration for the TRP; and perform a random access channel (RACH) procedure with a user equipment (UE) of the RAN according to the PRACH configuration for the TRP. wherein the performing the RACH procedure comprises sending, to the UE, a full cell radio network temporary identifier (C-RNTI) that identifies the UE within the RAN and a shortened C-RNTI that identifies the UE within the RAN.

17. A non-transitory computer-readable storage medium including instructions that, when executed by one or more processors of a user equipment (UE) for use for wireless communication with a radio access network (RAN), cause the UE to: receive, from a transmission reception point (TRP) of the RAN, a first synchronization signal and system information comprising a physical random access channel (PRACH) configuration for the TRP; and perform a random access channel (RACH) procedure with the TRP using the PRACH configuration for the TRP, wherein the performing the RACH procedure comprises receiving, from the TRP, a full cell radio network temporary identifier (C- RNT1) that identifies the UE within the RAN and a shortened C-RNTI that identifies the UE within the RAN.

18. A non-transitory computer-readable storage medium including instructions that, when executed by one or more processors of a transmission reception point (TRP) of a radio access network (RAN), cause the TRP to: broadcast a first synchronization signal and system information comprising a physical random access channel (PRACH) configuration for the TRP; and perform a random access channel (RACH) procedure with a user equipment (UE) of the RAN according to the PRACH configuration for the TRP. wherein the performing the RACH procedure comprises sending, to the UE, a full cell radio network temporary identifier (C-RNTI) that identifies the UE within the RAN and a shortened C-RNTI that identifies the UE within the RAN.

Images