Timing advance update for relaxed de-activated cells

Abstract

Certain aspects of the present disclosure provide techniques for updating a timing advance (TA) value for a deactivated cell. In an exemplary method, a user equipment receives a first instruction to transmit a physical random access channel (PRACH) on a first cell that is deactivated; and transmitting the PRACH on the first cell in response to the first instruction.

Description

Background Art Technical Field

[0001] Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for updating a timing advance (TA) value for a deactivated cell.

[0002] Related technologies

[0003] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcasts or other similar types of services. These wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available wireless communication system resources.

[0004] Although wireless communication systems have made tremendous technical progress over the years, challenges still exist. For example, complex and dynamic environments can still attenuate or block signals between wireless transmitters and wireless receivers. Therefore, there is a continued desire to improve the technical performance of wireless communication systems, including, for example: improving the speed and data carrying capacity of communications, improving the efficiency of using shared communication media, reducing the power used by transmitters and receivers when performing communications, improving the reliability of wireless communications, avoiding redundant transmission and / or reception and related processing, improving the coverage area of ​​wireless communications, increasing the number and types of devices that can access wireless communication systems, increasing the ability of different types of devices to communicate with each other, increasing the number and types of wireless communication media available for use, etc. Therefore, there is a need to further improve wireless communication systems to overcome the above-mentioned technical challenges and other challenges. Summary of the invention

[0005] One aspect provides a method for wireless communication by a user equipment (UE). The method includes receiving a first instruction for sending a physical random access channel (PRACH) on a deactivated first cell; and sending the PRACH on the first cell in response to the first instruction.

[0006] Another aspect provides a method for wireless communication by a network entity. The method includes sending an instruction for a UE to send a physical random access channel (PRACH) on a deactivated first cell; and sending an indication of a timing advance (TA) for the UE for the first cell based on the PRACH.

[0007] Other aspects provide: an apparatus operable to, configured to, or otherwise adapted to perform any one or more of the foregoing methods and / or those described elsewhere herein; a non-transitory computer-readable medium comprising instructions that, when executed by a processor of the apparatus, cause the apparatus to perform the foregoing methods and those described elsewhere herein; a computer program product embodied on a computer-readable storage medium comprising code for performing the foregoing methods and those described elsewhere herein; and / or an apparatus comprising components for performing the foregoing methods and those described elsewhere herein. By way of example, an apparatus may include a processing system, a device having a processing system, or a processing system cooperating through one or more networks.

[0008] For purposes of illustration, the following description and drawings set forth certain features. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings depict certain features of the various aspects described herein and should not be considered to limit the scope of the disclosure.

[0010] Figure 1 An example wireless communication network is depicted.

[0011] Figure 2 An example disaggregated base station architecture is depicted.

[0012] Figure 3 Aspects of an example base station and example user equipment are depicted.

[0013] Figure 4A , Figure 4B , Figure 4C and Figure 4D Various example aspects of data structures for a wireless communication network are described.

[0014] Figure 5 A call flow diagram depicting the four-step Random Access Channel (RACH) procedure.

[0015] Figure 6 A call flow diagram depicting the two-step RACH procedure.

[0016] Figure 7 Mobility scenarios according to aspects of the present disclosure are illustrated.

[0017] Figure 8 A timeline for performing TA update according to conventional techniques is illustrated.

[0018] Fig. 9 Depicted is a process flow for communications in a network between network entities, user equipment (UE), and candidate cells for deactivating cells in accordance with aspects of the present disclosure.

[0019] Fig.10 A table depicting five alternative techniques for performing TA update for a deactivated cell in accordance with aspects of the present disclosure.

[0020] Fig.11 is a timeline illustrating activities of a special cell (SpCell) and a UE according to aspects of the present disclosure.

[0021] Fig. 12A and Fig. 12B A scenario for selecting beams for receiving and transmitting Msg2, Msg3, and Msg4 according to aspects of the present disclosure is illustrated.

[0022] Fig.13 A method for wireless communication is described.

[0023] Fig.14 A method for wireless communication is described.

[0024] Fig.15 Aspects of an example communications device are depicted.

[0025] Fig.16 Aspects of an example communications device are depicted. DETAILED DESCRIPTION

[0026] Aspects of the present disclosure provide apparatus, methods, processing systems, and computer-readable media for updating a timing advance (TA) value for a deactivated cell.

[0027] TA is used for time synchronization and determines when the UE transmits an uplink transmission. TA allows the UE to adjust the timing of the UL transmission in order to align the UL transmission with the future transmission in the time domain. In other words, the TA value is designed to ensure that the uplink transmission arrives at a transmit / receive point (TRP) that is aligned with the boundary of the time slot. The TA value is typically determined via a random access channel (RACH) procedure, in which the UE transmits a first message called a physical RACH (PRACH) preamble to a network entity (e.g., a base station). The network entity responds with a random access response (RAR) message (MSG2) that may include a TA value.

[0028] When a UE moves in the network, it may move from an area served by a first cell to a new area served by another cell. In order to communicate with the new cell, the UE must have information about the TA for the new cell. Therefore, becoming active on a new cell usually involves some latency as the UE starts a random access procedure on the new cell and receives the TA for the new cell. If the UE already has the TA before becoming active on the new cell, the latency will be less and the communication will be more reliable, but in conventional systems, PRACH is not supported on cells that are deactivated for the UE.

[0029] The technology provided in the present disclosure enables the UE to send PRACH on the deactivated cell and receive TA updates for the deactivated cell. By enabling the UE to receive TA updates for the deactivated cell, the UE may be able to start communicating with the cell faster, which may reduce latency and improve the reliability of UE-to-network communications when the UE is moving.

[0030] Introduction to wireless communication networks

[0031] The techniques and methods described herein can be used in various wireless communication networks. Although various aspects may be described herein using terms commonly associated with 3G, 4G and / or 5G wireless technologies, various aspects of the present disclosure may also be applicable to other communication systems and standards not explicitly mentioned herein.

[0032] Figure 1 An example of a wireless communication network 100 is depicted in which various aspects described herein may be implemented.

[0033] In general, the wireless communication network 100 includes various network entities (alternatively, network elements or network nodes). A network entity is typically a communication device and / or a communication function performed by a communication device (e.g., user equipment (UE), base station (BS), component of a BS, server, etc.). For example, various functions of a network and various devices associated with and interacting with the network may be considered network entities. In addition, the wireless communication network 100 includes ground aspects, such as ground-based network entities (e.g., BS 102), and non-ground aspects, such as satellites 140 and aircraft 145, which may include airborne network entities (e.g., one or more BSs) capable of communicating with other network elements (e.g., ground BSs) and user equipment.

[0034] In the depicted example, the wireless communication network 100 includes a BS 102, a UE 104, and one or more core networks (such as an evolved packet core (EPC) 160 and a 5G core (5GC) network 190) that interoperate to provide communication services over various communication links (including wired and wireless links).

[0035] Figure 1 Various example UEs 104 are depicted, which may more generally include: a cellular phone, a smart phone, a Session Initiation Protocol (SIP) phone, a laptop, a personal digital assistant (PDA), a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player, a camera, a game console, a tablet computer, a smart device, a wearable device, a vehicle, an electric meter, a gas pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor / actuator, a display, an Internet of Things (IoT) device, an Always-On (AON) device, an edge processing device, or other similar devices. UE 104 may also be more generally referred to as a mobile device, a wireless device, a wireless communication device, a station, a mobile station, a subscriber station, a mobile subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a remote device, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, and others.

[0036] BS 102 wirelessly communicates with (e.g., sends signals to or receives signals from) UE 104 via communication link 120. Communication link 120 between BS 102 and UE 104 may include uplink (UL) (also referred to as a reverse link) transmissions from UE 104 to BS 102 and / or downlink (DL) (also referred to as a forward link) transmissions from BS 102 to UE 104. In various aspects, communication link 120 may use multiple-input multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity.

[0037] BS 102 may generally include: NodeB, enhanced NodeB (eNB), next generation enhanced NodeB (ng-eNB), next generation NodeB (gNB or gNodeB), access point, base transceiver, radio base station, radio transceiver, transceiver function, transmission and reception point, and / or other. Each of BS 102 may provide communication coverage for a corresponding geographic coverage area 110, which may sometimes be referred to as a cell, and may overlap in some cases (e.g., a small cell 102' may have a coverage area 110' that overlaps with the coverage area 110 of a macro cell). For example, a BS may provide communication coverage for a macro cell (covering a relatively large geographic area), a pico cell (covering a relatively small geographic area, such as a stadium), a femto cell (relatively small geographic area (e.g., a home)), and / or other types of cells.

[0038] Although BS102 is depicted as a single communication device in various aspects, BS102 can be implemented in various configurations. For example, one or more components of the base station may be decomposed, including a central unit (CU), one or more distributed units (DU), one or more radio units (RU), a near real-time (near RT) RAN intelligent controller (RIC), or a non-real-time (non-RT) RIC, to name a few examples. In another example, various aspects of the base station may be virtualized. More generally, a base station (e.g., BS102) may include components located at a single physical location or components located at various physical locations. In an example in which the base station includes components located at various physical locations, the various components may each perform a function so that the various components together implement functions similar to those of a base station located at a single physical location. In some aspects, a base station including components located at various physical locations may be referred to as a decomposed radio access network architecture (such as an open RAN (O-RAN) or virtualized RAN (VRAN) architecture). Figure 2 An example decomposed base station architecture is depicted and described.

[0039] Different BSs 102 within the wireless communication network 100 may also be configured to support different radio access technologies (such as 3G, 4G, and / or 5G). For example, a BS 102 configured for 4G LTE (collectively referred to as the Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) may interface with the EPC 160 via a first backhaul link 132 (e.g., an S1 interface). A BS 102 configured for 5G (e.g., 5G NR or Next Generation RAN (NG-RAN)) may interface with the 5GC 190 via a second backhaul link 184. The BSs 102 may communicate with each other directly or indirectly (e.g., via the EPC 160 or the 5GC 190) over a third backhaul link 134 (e.g., an X2 interface), which may be wired or wireless.

[0040] The wireless communication network 100 may subdivide the electromagnetic spectrum into various categories, frequency bands, channels, or other characteristics. In some aspects, the subdivision is provided based on wavelength and frequency, where frequency may also be referred to as a carrier, subcarrier, channel, tone, or subband. For example, 3GPP currently defines frequency range 1 (FR1) as including 410 MHz-7125 MHz, which is often (interchangeably) referred to as "below 6 GHz". Similarly, 3GPP currently defines frequency range 2 (FR2) as including 24,250 MHz-52,600 MHz, which is sometimes (interchangeably) referred to as "millimeter wave" ("mmW" or "mmWave"). A base station (e.g., a mmWave base station such as BS180) configured to communicate using mmWave / near mmWave radio bands may utilize beamforming (e.g., 182) with a UE (e.g., 104) to improve path loss and range.

[0041] The communication link 120 between the BS 102 and, for example, the UE 104 may be through one or more carriers, which may have different bandwidths (e.g., 5 MHz, 10 MHz, 15 MHz, 20 MHz, 100 MHz, 400 MHz, and / or other MHz) and may be aggregated in various aspects. The carriers may or may not be adjacent to each other. The allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL ​​compared to UL).

[0042] Communications using higher frequency bands may have higher path loss and shorter range than communications at lower frequencies. Figure 1 180) may utilize beamforming 182 with UE 104 to improve path loss and range. For example, BS 180 and UE 104 may each include multiple antennas, such as antenna elements, antenna panels, and / or antenna arrays, to facilitate beamforming. In some cases, BS 180 may send beamformed signals to UE 104 in one or more transmit directions 182'. UE 104 may receive beamformed signals from BS 180 in one or more receive directions 182". UE 104 may also send beamformed signals to BS 180 in one or more transmit directions 182". BS 180 may also receive beamformed signals from UE 104 in one or more receive directions 182'. BS 180 and UE 104 may then perform beam training to determine the best receive and transmit directions for each of BS 180 and UE 104. It is noteworthy that the transmit direction and receive direction of BS 180 may be the same or different. Similarly, the transmit direction and receive direction of UE 104 may be the same or different.

[0043] Wireless communication network 100 also includes Wi-Fi AP 150 that communicates with Wi-Fi station (STA) 152 via communication link 154 in, for example, the 2.4 GHz and / or 5 GHz unlicensed spectrum.

[0044] Certain UEs 104 may communicate with each other using a device-to-device (D2D) communication link 158. The D2D communication link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH), a physical sidelink discovery channel (PSDCH), a physical sidelink shared channel (PSSCH), a physical sidelink control channel (PSCCH), and / or a physical sidelink feedback channel (PSFCH).

[0045] The EPC 160 may include various functional components, including: a mobility management entity (MME) 162, other MMEs 164, a serving gateway 166, a multimedia broadcast multicast service (MBMS) gateway 168, a broadcast multicast service center (BM-SC) 170, and / or a packet data network (PDN) gateway 172, such as in the depicted example. The MME 162 may communicate with a home subscriber server (HSS) 174. The MME 162 is a control node that handles signaling between the UE 104 and the EPC 160. In general, the MME 162 provides bearer and connection management.

[0046] Generally, user Internet Protocol (IP) packets are delivered through the Serving Gateway 166, which itself is connected to the PDN Gateway 172. The PDN Gateway 172 provides UE IP address allocation and other functions. The PDN Gateway 172 and the BM-SC 170 are connected to the IP Services 176, which may include, for example, the Internet, an Intranet, an IP Multimedia Subsystem (IMS), a Packet Switched (PS) streaming media service, and / or other IP services.

[0047] The BM-SC 170 may provide functionality for MBMS user service provisioning and delivery. The BM-SC 170 may serve as an entry point for content provider MBMS delivery, may be used to authorize and initiate MBMS bearer services within a public land mobile network (PLMN), and / or may be used to schedule MBMS delivery. The MBMS Gateway 168 may be used to distribute MBMS services to BSs 102 belonging to a multicast broadcast single frequency network (MBSFN) area broadcasting a specific service, and / or may be responsible for session management (start / stop) and for collecting eMBMS related charging information.

[0048] 5GC 190 may include various functional components, including: access and mobility management function (AMF) 192, other AMFs 193, session management function (SMF) 194, and user plane function (UPF) 195. AMF 192 may communicate with unified data management (UDM) 196.

[0049] AMF 192 is a control node that handles signaling between UE 104 and 5GC 190. AMF 192 provides, for example, Quality of Service (QoS) flow and session management.

[0050] Internet Protocol (IP) packets are delivered through UPF 195, which is connected to IP Services 197 and provides UE IP address allocation and other functions for 5GC 190. IP Services 197 may include, for example, the Internet, Intranet, IMS, PS streaming services, and / or other IP services.

[0051] In various aspects, a network entity or network node may be implemented as a converged base station, a decomposed base station, a component of a base station, an integrated access and backhaul (IAB) node, a relay node, a sidelink node, to name a few examples.

[0052] Figure 2 An example disaggregated base station 200 architecture is depicted. The disaggregated base station 200 architecture may include one or more central units (CUs) 210 that may communicate directly with a core network 220 via a backhaul link, or indirectly with the core network 220 through one or more disaggregated base station units, such as a near real-time (near-RT) RAN intelligent controller (RIC) 225 via an E2 link, or a non-real-time (non-RT) RIC 215 associated with a service management and orchestration (SMO) framework 205, or both. The CU 210 may communicate with one or more distributed units (DUs) 230 via respective midhaul links, such as an F1 interface. The DU 230 may communicate with one or more radio units (RUs) 240 via respective fronthaul links. The RU 240 may communicate with respective UEs 104 via one or more radio frequency (RF) access links. In some implementations, a UE 104 may be served simultaneously by multiple RUs 240.

[0053] Each of the units, such as CU 210, DU 230, RU 240, and near-RT RIC 225, non-RT RIC 215, and SMO framework 205, may include one or more interfaces or be coupled to one or more interfaces, which are configured to receive or send signals, data, or information (collectively referred to as signals) via a wired or wireless transmission medium. Each unit in the unit or an associated processor or controller that provides instructions to the communication interface of the unit may be configured to communicate with one or more of the other units via a transmission medium. For example, the units may include a wired interface that is configured to receive or send signals to one or more of the other units via a wired transmission medium. Additionally or alternatively, the unit may include a wireless interface that may include a receiver, a transmitter, or a transceiver (such as a radio frequency (RF) transceiver) that is configured to receive or send signals, or both, to one or more of the other units on a wireless transmission medium.

[0054] In some aspects, CU 210 may host one or more higher layer control functions. Such control functions may include radio resource control (RRC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), etc. Each control function may be implemented using an interface that is configured to communicate signals with other control functions hosted by CU 210. CU210 may be configured to handle user plane functionality (e.g., central unit-user plane (CU-UP)), control plane functionality (e.g., central unit-control plane (CU-CP)), or a combination thereof. In some specific implementations, CU 210 may be logically divided into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP unit may communicate bidirectionally with the CU-CP unit via an interface (such as an E1 interface). As needed, CU 210 may be implemented to communicate with DU 230 for network control and signaling.

[0055] DU 230 may correspond to a logical unit that includes one or more base station functions for controlling the operation of one or more RUs 240. In some aspects, DU 230 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, etc.) at least in part according to functional divisions such as those defined by the 3rd Generation Partnership Project (3GPP). In some aspects, DU 230 may further host one or more low PHY layers. Each layer (or module) may be implemented using an interface that is configured to communicate signals with other layers (and modules) hosted by DU 230 or with control functions hosted by CU 210.

[0056] The lower layer functionality may be implemented by one or more RUs 240. In some deployments, a RU 240 controlled by a DU 230 may correspond to a logical node that hosts RF processing functions or low PHY layer functions (such as performing Fast Fourier Transform (FFT), Inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, etc.), or both, based at least in part on a functional partitioning (such as a lower layer functional partitioning). In such an architecture, the RU 240 may be implemented to handle over-the-air (OTA) communications with one or more UEs 104. In some implementations, real-time and non-real-time aspects of control plane and user plane communications with the RU 240 may be controlled by the corresponding DU 230. In some scenarios, this configuration may enable the implementation of the DU 230 and the CU 210 in a cloud-based RAN architecture (such as a vRAN architecture).

[0057] The SMO framework 205 may be configured to support RAN deployment and provisioning of non-virtualized network elements and virtualized network elements. For non-virtualized network elements, the SMO framework 205 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements, which may be managed via an operation and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO framework 205 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 290) to perform network element lifecycle management (such as instantiating virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements may include, but are not limited to, CU 210, DU 230, RU 240, and near-RT RIC 225. In some specific implementations, the SMO framework 205 may communicate with hardware aspects of the 4G RAN (such as an open eNB (O-eNB) 211) via the O1 interface. In addition, in some specific implementations, the SMO framework 205 may communicate directly with one or more RUs 240 via the O1 interface. The SMO framework 205 may also include a non-RT RIC 215 configured to support the functionality of the SMO framework 205 .

[0058] The non-RT RIC 215 may be configured to include logic functions that enable non-real-time control and optimization of RAN elements and resources, artificial intelligence / machine learning (AI / ML) workflows including model training and updating, or policy-based guidance of applications / features in the near-RT RIC 225. The non-RT RIC 215 may be coupled to or in communication with the near-RT RIC 225 (such as via an A1 interface). The near-RT RIC 225 may be configured to include logic functions that enable near-real-time control and optimization of RAN elements and resources via data collection and actions through an interface (such as via an E2 interface) that connects one or more CUs 210, one or more DUs 230, or both, and the O-eNB with the near-RT RIC 225.

[0059] In some implementations, in order to generate an AI / ML model to be deployed in the near-RT RIC 225, the non-RT RIC 215 may receive parameters or external enrichment information from an external server. Such information may be utilized by the near-RT RIC 225 and may be received from a non-network data source or from a network function at the SMO framework 205 or the non-RT RIC 215. In some examples, the non-RT RIC 215 or the near-RT RIC 225 may be configured to tune RAN behavior or performance. For example, the non-RT RIC 215 may monitor long-term trends and patterns of performance and employ AI / ML models to perform corrective actions through the SMO framework 205 (such as via reconfiguration of O1) or via the creation of RAN management policies (such as A1 policies).

[0060] Figure 3 Aspects of an example BS 102 and UE 104 are depicted.

[0061] In general, BS 102 includes various processors (e.g., 320, 330, 338, and 340), antennas 334a-334t (collectively 334), transceivers 332a-332t (collectively 332) including modulators and demodulators, and other aspects that enable wireless transmission of data (e.g., data source 312) and wireless reception of data (e.g., data sink 339). For example, BS 102 can transmit and receive data between BS 102 and UE 104. BS 102 includes a controller / processor 340 that can be configured to implement various functions described herein related to wireless communication.

[0062] Generally speaking, the UE 104 includes various processors (e.g., 358, 364, 366, and 380), antennas 352a-352r (collectively 352), transceivers 354a-354r (collectively 354) including modulators and demodulators, and other aspects that enable wireless transmission of data (e.g., retrieved from a data source 362) and wireless reception of data (e.g., provided to a data sink 360). The UE 104 includes a controller / processor 380 that can be configured to implement various functions described herein related to wireless communications.

[0063] Regarding example downlink transmissions, BS 102 includes a transmit processor 320 that can receive data from a data source 312 and control information from a controller / processor 340. The control information can be for a physical broadcast channel (PBCH), a physical control format indicator channel (PCFICH), a physical HARQ indicator channel (PHICH), a physical downlink control channel (PDCCH), a group common PDCCH (GC PDCCH), and / or others. In some examples, the data can be for a physical downlink shared channel (PDSCH).

[0064] The transmit processor 320 may process (e.g., encode and symbol map) data and control information to obtain data symbols and control symbols, respectively. The transmit processor 320 may also generate reference symbols (such as for a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a PBCH demodulation reference signal (DMRS), and a channel state information reference signal (CSI-RS)).

[0065] The transmit (TX) multiple-input multiple-output (MIMO) processor 330 may perform spatial processing (e.g., pre-decoding) on ​​data symbols, control symbols, and / or reference symbols, where applicable, and may provide an output symbol stream to a modulator (MOD) in a transceiver 332a-332t. Each modulator in the transceiver 332a-332t may process a corresponding output symbol stream to obtain an output sample stream. Each modulator may further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The downlink signals from the modulators in the transceivers 332a-332t may be transmitted via antennas 334a-334t, respectively.

[0066] To receive downlink transmissions, UE 104 includes antennas 352a-352r that can receive downlink signals from BS 102 and can provide received signals to demodulators (DEMODs) in transceivers 354a-354r, respectively. Each demodulator in transceivers 354a-354r can condition (e.g., filter, amplify, downconvert, and digitize) a corresponding received signal to obtain input samples. Each demodulator can further process the input samples to obtain received symbols.

[0067] A MIMO detector 356 may obtain received symbols from all demodulators in transceivers 354a-354r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 358 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 104 to a data sink 360, and provide decoded control information to a controller / processor 380.

[0068] With respect to example uplink transmissions, the UE 104 also includes a transmit processor 364 that may receive and process data from a data source 362 (e.g., for a PUSCH) and control information from a controller / processor 380 (e.g., for a physical uplink control channel (PUCCH)). The transmit processor 364 may also generate reference symbols for reference signals (e.g., for a sounding reference signal (SRS)). The symbols from the transmit processor 364 may be pre-decoded by a TX MIMO processor 366, if applicable, further processed by a modulator in the transceivers 354a-354r (e.g., for SC-FDM), and transmitted to the BS 102.

[0069] At BS 102, uplink signals from UE 104 may be received by antennas 334 a-334 t, processed by demodulators in transceivers 332 a-332 t, detected by MIMO detector 336 if applicable, and further processed by receive processor 338 to obtain decoded data and control information transmitted by UE 104. Receive processor 338 may provide decoded data to data sink 339 and decoded control information to controller / processor 340.

[0070] Memory 342 and memory 382 may store data and program codes for BS 102 and UE 104, respectively.

[0071] A scheduler 344 may schedule UEs for data transmission on the downlink and / or uplink.

[0072] In various aspects, BS 102 may be described as sending and receiving various types of data associated with the methods described herein. In these contexts, "sending" may refer to various mechanisms for outputting data, such as outputting data from a data source 312, a scheduler 344, a memory 342, a transmit processor 320, a controller / processor 340, a TX MIMO processor 330, a transceiver 332a-332t, an antenna 334a-334t, and / or other aspects described herein. Similarly, "receiving" may refer to various mechanisms for obtaining data, such as obtaining data from an antenna 334a-334t, a transceiver 332a-332t, a RX MIMO detector 336, a controller / processor 340, a receive processor 338, a scheduler 344, a memory 342, and / or other aspects described herein.

[0073] In various aspects, the UE 104 may also be described as sending and receiving various types of data associated with the methods described herein. In these contexts, "sending" may refer to various mechanisms for outputting data, such as outputting data from a data source 362, a memory 382, ​​a transmit processor 364, a controller / processor 380, a TX MIMO processor 366, a transceiver 354a-354t, an antenna 352a-352t, and / or other aspects described herein. Similarly, "receiving" may refer to various mechanisms for obtaining data, such as obtaining data from an antenna 352a-352t, a transceiver 354a-354t, a RX MIMO detector 356, a controller / processor 380, a receive processor 358, a memory 382, ​​and / or other aspects described herein.

[0074] In some aspects, the processor may be configured to perform various operations (such as those associated with the methods described herein) and send (output) data to or receive (obtain) data from another interface configured to send or receive data, respectively.

[0075] Figure 4A , Figure 4B , Figure 4C and Figure 4D Describes a method for use in a wireless communication network such as Figure 1 Various aspects of the data structure of the wireless communication network 100).

[0076] Specifically, Figure 4A is a diagram 400 illustrating an example of a first subframe within a 5G (e.g., 5G NR) frame structure, Figure 4B is a diagram 430 illustrating an example of a DL channel within a 5G subframe, Figure 4C is a diagram 450 illustrating an example of a second subframe within a 5G frame structure, and Figure 4D FIG480 is a diagram illustrating an example of UL channels within a 5G subframe.

[0077] Wireless communication systems may utilize orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) on both the uplink and downlink. Such systems may also support half-duplex operation using time division duplex (TDD). OFDM and single carrier frequency division multiplexing (SC-FDM) can be used to maximize the system bandwidth (e.g., Figure 4B and Figure 4D The modulation symbols may be transmitted in the frequency domain using OFDM and / or in the time domain using SC-FDM.

[0078] The wireless communication frame structure may be frequency division duplex (FDD), where for a particular set of subcarriers, subframes within the set of subcarriers are dedicated to either DL or UL. The wireless communication frame structure may also be time division duplex (TDD), where for a particular set of subcarriers, subframes within the set of subcarriers are dedicated to both DL and UL.

[0079] exist Figure 4A and Figure 4C In the wireless communication frame structure, TDD is used, where D is DL, U is UL, and X is used flexibly between DL / UL. The UE can be configured with a time slot format (dynamically configured by DL control information (DCI) or semi-statically / statically configured by radio resource control (RRC) signaling) through the received time slot format indicator (SFI). In the depicted example, the 10ms frame is divided into 10 equally sized 1ms subframes. Each subframe may include one or more time slots. In some examples, each time slot may include 7 or 14 symbols, depending on the time slot format. The subframe may also include micro-time slots, which typically have fewer symbols than the entire time slot. Other wireless communication technologies may have different frame structures and / or different channels.

[0080] In certain aspects, the number of time slots within a subframe is based on the time slot configuration and the parameter set. For example, for time slot configuration 0, different parameter sets (μ) 0 to 5 allow for 1, 2, 4, 8, 16, and 32 time slots per subframe, respectively. For time slot configuration 1, different parameter sets 0 to 2 allow for 2, 4, and 8 time slots per subframe, respectively. Thus, for time slot configuration 0 and parameter set μ, there are 14 symbols / time slot and 2μ time slots / subframe. The subcarrier spacing and symbol length / duration are a function of the parameter set. The subcarrier spacing may be equal to 2 μ × 15kHz, where μ is parameter set 0 to 5. Thus, parameter set μ=0 has a subcarrier spacing of 15kHz, and parameter set μ=5 has a subcarrier spacing of 480kHz. The symbol length / duration is inversely related to the subcarrier spacing. Figure 4A , Figure 4B , Figure 4C and Figure 4D An example is provided for slot configuration 0 with 14 symbols per slot and parameter set μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs.

[0081] like Figure 4A , Figure 4B , Figure 4C and Figure 4DAs depicted in , a resource grid can be used to represent a frame structure. Each time slot includes a resource block (RB) (also called a physical RB (PRB)) extending, for example, 12 consecutive subcarriers. The resource grid is divided into a plurality of resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.

[0082] like Figure 4A As illustrated, some REs carry Figure 1 and Figure 3 The RS may include a demodulation RS (DMRS) and / or a channel state information reference signal (CSI-RS) for channel estimation at the UE. The RS may also include a beam measurement RS (BRS), a beam refinement RS (BRRS), and / or a phase tracking RS (PT-RS).

[0083] Figure 4B Examples of various DL channels within a subframe of a frame are illustrated.The Physical Downlink Control Channel (PDCCH) carries DCI within one or more Control Channel Elements (CCEs), each CCE comprising, for example, nine RE Groups (REGs), each REG comprising, for example, four consecutive REs in an OFDM symbol.

[0084] The primary synchronization signal (PSS) may be in symbol 2 of a particular subframe of a frame. The PSS is transmitted by a UE (e.g., Figure 1 and Figure 3 104) is used to determine subframe / symbol timing and physical layer identification.

[0085] A Secondary Synchronization Signal (SSS) may be within symbol 4 of a particular subframe of a frame. The SSS is used by the UE to determine the physical layer cell identity group number and radio frame timing.

[0086] Based on the physical layer identifier and the physical layer cell identifier group number, the UE can determine the physical cell identifier (PCI). Based on the PCI, the UE can determine the location of the aforementioned DMRS. The physical broadcast channel (PBCH) carrying the master information block (MIB) can be logically grouped with the PSS and SSS to form a synchronization signal (SS) / PBCH block. The MIB provides the system frame number (SFN) and the number of RBs in the system bandwidth. The physical downlink shared channel (PDSCH) carries user data, broadcast system information (such as system information blocks (SIBs)) that is not sent via the PBCH, and / or paging messages.

[0087] As in Figure 4CAs illustrated in , some REs carry DMRS for channel estimation at the base station (indicated as R for a specific configuration, but other DMRS configurations are possible). The UE may send DMRS for PUCCH and DMRS for PUSCH. The PUSCH DMRS may be sent, for example, in the first one or two symbols of the PUSCH. The PUCCH DMRS may be sent in different configurations depending on whether a short PUCCH or a long PUCCH is sent and depending on the specific PUCCH format used. UE 104 may send a sounding reference signal (SRS). The SRS may be sent, for example, in the last symbol of a subframe. The SRS may have a comb structure, and the UE may send the SRS on one of the comb structures in the comb structure. The SRS may be used by the base station for channel quality estimation to achieve frequency-dependent scheduling of the UL.

[0088] Figure 4D Examples of various UL channels within a subframe of a frame are illustrated. The PUCCH may be located at a position as indicated in one configuration. The PUCCH carries uplink control information (UCI), such as scheduling requests, channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI), and HARQ ACK / NACK feedback. The PUSCH carries data and may additionally be used to carry a buffer status report (BSR), a power headroom report (PHR), and / or UCI.

[0089] Example RACH Procedure

[0090] The random access channel (RACH) is so named because it refers to a wireless channel (medium) that can be shared by multiple UEs and used by these UEs to (randomly) access the network for communication. For example, RACH can be used for call establishment and access network for data transmission. In some cases, when the UE switches from radio resource control (RRC) connection idle mode to active mode, or when switching in RRC connection mode, RACH can be used for initial access to the network. In addition, when the UE is in RRC idle or RRC inactive mode, and when reestablishing the connection with the network, RACH can be used for downlink (DL) and / or uplink (UL) data arrival.

[0091] Figure 55 is a timing (or "call flow") diagram 500 illustrating an example four-step RACH procedure in accordance with certain aspects of the present disclosure. A first message (MSG1) may be transmitted from a UE to a network entity (e.g., a BS such as a gNB) on a physical random access channel (PRACH). In this case, MSG1 may include only a RACH preamble. The network entity may respond with a random access response (RAR) message (MSG2), which may include an identifier (ID) of the RACH preamble, a timing advance (TA), an uplink grant, a cell radio network temporary identifier (C-RNTI), and a fallback indicator. MSG2 may include a PDCCH communication including control information regarding subsequent communications on the PDSCH, as illustrated. In response to MSG2, MSG3 is sent from the UE to the network entity on the PUSCH. MSG3 may include one or more of an RRC connection request, a tracking area update request, a system information request, a location lock or positioning signal request, or a scheduling request. The network entity then responds with MSG 4 which may include a contention resolution message.

[0092] In some cases, in order to speed up access, a two-step RACH procedure may be supported. As the name implies, the two-step RACH procedure can effectively "collapse" the four messages of the four-step RACH procedure into two messages.

[0093] Figure 6 is a call flow diagram 600 illustrating an example two-step RACH procedure in accordance with certain aspects of the present disclosure. As illustrated, a UE may be configured with parameters for SSB monitoring and RACH procedures via system information (SI) and / or RRC signaling.

[0094] For a two-step RACH procedure, a first enhancement message (msgA) may be transmitted from the UE to the network entity. In some aspects, msgA includes some or all of the information of MSG1 and MSG3 from the four-step RACH procedure (effectively combining MSG1 and MSG3). For example, msgA may include MSG1 and MSG3 multiplexed together, such as using one of time division multiplexing or frequency division multiplexing. In some aspects, msgA includes a RACH preamble and a payload for random access. For example, the msgA payload may include a UE-ID and other signaling information (e.g., a buffer status report (BSR)) or a scheduling request (SR). The BS may respond with a random access response (RAR) message (msgB), which may effectively combine MSG2 and MSG4 described above. For example, msgB may include an ID of a RACH preamble, a timing advance (TA), a backoff indicator, a contention resolution message, an UL / DL grant, and a transmit power control (TPC) instruction.

[0095] In the two-step RACH procedure, msgA may include a RACH preamble and a payload. In some cases, the RACH preamble and the payload may be transmitted in the msgA transmission opportunity.

[0096] The random access message (msgA) transmission opportunity generally includes the msgA preamble opportunity (used to send the preamble signal) and the msgA payload opportunity for sending the PUSCH. The msgA preamble transmission generally involves:

[0097] (1) Selection of preamble sequence; and

[0098] (2) Selection of preamble timing (for sending the selected preamble sequence) in the time / frequency domain.

[0099] The msgA payload sending generally involves:

[0100] (1) Construction of random access message payload (DMRS / PUSCH); and

[0101] (2) Selection of one or more PUSCH resource units (PRUs) in the time / frequency domain to send the message (payload).

[0102] In some cases, the UE monitors SSB transmissions transmitted (by the gNB using different beams) and associated with a limited set of time / frequency resources defining RACH occasions (ROs) and PRUs. Upon detecting an SSB, the UE may select the RO and one or more PRUs associated with the SSB for MSG1 / msgA transmissions.

[0103] There are several benefits to the two-step RACH procedure, such as speed of access and the ability to transmit relatively small amounts of data without the overhead of the entire four-step RACH procedure to establish a connection (as the four-step RACH message may be larger than the payload).

[0104] The two-step RACH procedure may operate in any RRC state and with any supported cell size.Networks using the two-step RACH procedure may typically support contention-based random access (CBRA) message (eg, msgA) transmissions within a limited range of payload sizes and with a limited number of MCS levels.

[0105] After the UE has selected an SSB (beam), for that SS block, there are predefined one or more ROs with specific time and frequency offsets and directions (eg, specific to the selected SSB).

[0106] The SSB is associated with the RO to let the gNB know what beam the UE has acquired / is using (usually referred to as beam establishment). One SSB can be associated with one or more ROs, or more than one SSB can be associated with one RO. The association is typically performed first in the frequency domain, then in the time domain within a RACH slot, and then in the time domain across RACH slots (e.g., starting from a lower SSB index). The association period is typically defined as the minimum number of RACH configuration periods such that all (configured) SSB beams are mapped into a RO.

[0107] Overview of L1 / L2-based mobility

[0108] For L1 / L2-based mobility, the network may configure (e.g., via RRC signaling) a set of cells for L1 / L2 mobility (referred to herein as the L1 / L2 mobility configured cell set). At any given time, the network may also configure (via L1 / L2 signaling) an L1 / L2 mobility activated cell set, which refers to a set of cells in the configured set that are activated and can be easily used for data and control transmission. The network may also configure (signal) an L1 / L2 mobility deactivated cell set, which refers to a set of cells in the configured set that are deactivated and can be easily activated by L1 / L2 signaling.

[0109] L1 / L2 signaling can be used for mobility management of the active set. For example, L1 / L2 signaling can be used to activate / deactivate cells in the set, select beams within the activated cells, and update / switch PCells. This dynamic signaling can help provide seamless mobility within the activated cells in the set. In other words, as the UE moves, cells from the set are deactivated and activated by L1 / L2 signaling. The cells to be activated and deactivated can be based on various factors, such as signal quality (measurements) and load.

[0110] In some cases, all cells in the L1 / L2 mobility configuration cell set may belong to the same DU. This may be similar to carrier aggregation (CA), but the cells may be on the same carrier frequency. The size of the cell set configured for L1 / L2 mobility signaling may vary. In general, the cell set size may be selected to be large enough to cover a meaningful mobility area.

[0111] In some cases, the UE may be provided with a subset of deactivated cells as a candidate cell set from which the UE may autonomously select cells to add to the activated cell set. The decision whether to add a cell from the candidate cell set to the activated cell set may be based on various factors, such as measured channel quality and load information. In some cases, the UE's ability to autonomously select cells to add to the activated cell set may be similar to the UE decision when configured for conditional handover (CHO) to quickly and efficiently add prepared cells.

[0112] In some cases, each cell may be served by a RU. Each RU in the RU may have multi-carrier (N CCs) support. In this case, each CC may be a cell (e.g., cell 2 and cell 2' may be different CCs of the same RU). In this case, activation / deactivation may be performed in a carrier group (cell).

[0113] For primary cell (PCell) management, L1 / L2 signaling can be used to set (select) the PCell from pre-configured options within the activated cell set. In some cases, when the new PCell is not from the activated cell set for L1 / L2 mobility, L3 mobility can be used for PCell change (L3 handover). In this case, at L3 handover, RRC signaling can update the cell set for L1 / L2 mobility.

[0114] Aspects related to updating the timing advance for deactivated cells

[0115] In a system supporting L1 / L2 based mobility, it may be beneficial for the UE to maintain the timing advance (TA) on a candidate primary cell (PCell) so that no TA update is required after the candidate PCell is selected as the new PCell. However, as described above, in conventional systems, PRACH is not supported on a deactivated cell.

[0116] In conventional systems, the UE does not send PRACH, Sounding Reference Signal (SRS) or Physical Uplink Control Channel (PUCCH) on either the deactivated primary secondary cell (PSCell) or the deactivated secondary cell (SCell). In addition, using conventional techniques, the UE will not receive the Physical Downlink Control Channel (PDCCH) on or for the deactivated SCell as a candidate PCell, and will not report the CSI of the deactivated SCell as a candidate PCell.

[0117] Therefore, various aspects of the present disclosure provide a technique for updating a TA for a deactivated cell. The provided technique includes: a UE receiving an instruction for sending a PRACH on a deactivated first cell, and sending the PRACH on the first cell in response to the instruction. The provided technique also includes: the UE receiving a TA determined based on the PRACH, and using the TA to send a signal to the first cell.

[0118] Figure 7 A mobility scenario 700 according to various aspects of the present disclosure is illustrated, wherein a UE 704 moves away from a PCell 702 and is instructed to switch / reselect to a new PCell among a set of preconfigured candidate PCells 706, 708, and 710, which are determined based on the UE's L1 measurements of those cells. As illustrated, PCell 702 is in a timing advance group (TAG) 0, while candidate PCells 706, 708, and 710 are in TAG 1, TAG 2, and TAG 3, respectively. In the illustrated scenario, the candidate PCells are not activated until one of the candidate PCells is selected as the new PCell. In the illustrated scenario, candidate PCell 706 is selected as the new PCell, and other cells (not shown) in TAG 1 are not activated.

[0119] According to various aspects of the present disclosure, a UE may send a PRACH to any of the deactivated candidate PCells and receive a TA update for the deactivated candidate PCell based on the PRACH. The TA update may be determined by the gNB and sent to the UE by a special cell (SpCell) of the UE or by the candidate PCell.

[0120] In conventional systems, to update the TA for a cell, the cell may be activated, the UE performs a PRACH on the activated cell, the UE receives the TA update for the cell, and once the TA update is complete, the UE may then deactivate the cell.

[0121] The advantage of the provided technique compared to the above process is that the UE only prepares and performs PRACH transmission on the deactivated cell without preparing other functions such as PDCCH monitoring, CSI reporting, HARQ processing, etc. Therefore, compared to the above process, both the UE complexity and power consumption for maintaining such deactivated cells can be reduced, and the gNB can trigger the UE to send PRACH on the deactivated cell at any time, when the UE's latency and power consumption are lower than those used when the candidate cell is fully activated. This process is similar to the process for radio link monitoring (RLM), beam failure detection (BFD) and transmission control indication (TCI) activation on deactivated SpCells that have been introduced in some systems.

[0122] In another conventional technique, the TA update for the deactivation candidate SpCell may be derived based on the receive timing difference between the current active SpCell and the deactivation candidate SpCell. However, this technique may not be accurate if the DL transmit timing difference between the active SpCell and the deactivation candidate SpCell is large and unknown to the gNB (which may be a typical case), especially when the active SpCell and the deactivation candidate SpCell are on different frequencies.

[0123] Figure 8 A timeline 800 of a conventional technique for performing a TA update is illustrated. In the conventional technique, a PRACH-based TA update includes five steps. In the first step, the gNB transmits a PDCCH containing a DCI directing the UE to perform a TA update for a cell. In the second step, the UE sends a PRACH (also referred to as message 1 (Msg1) of a RACH procedure) on the cell where the TA is being updated. In the third step, the gNB transmits a random access response (RAR, also referred to as message 2 (Msg2) of a RACH procedure) including a TA instruction, which is applied by the UE to the corresponding TAG for the cell. In the fourth step, the UE sends a PUSCH (also referred to as message 3 (Msg3) of a RACH procedure), which includes a cell-specific radio network temporary identifier (C-RNTI) medium access control control element (MAC-CE) for the UE when the random access procedure is a contention-based random access (CBRA), and includes a buffer status report (BSR) or data when the random access procedure is a non-contention random access (CFRA). In the fifth step, for CBRA, the gNB responds to the PUSCH with a DCI that is scrambled by the UE’s C-RNTI and schedules a new UL grant for the UE.

[0124] In the conventional technology described above, a PDCCH containing DCI instructing the UE to perform TA update may be transmitted from the SCell for SCell TA update, and the UE sends a PRACH to the SCell. Other transmissions in the third, fourth and fifth steps are transmitted to or from the SpCell for the UE.

[0125] In conventional technology, a PDCCH containing DCI instructing the UE to perform a TA update may trigger the UE to perform CFRA or CBRA. When the PDCCH triggers the UE to perform CFRA, the PRACH preamble, synchronization signal block (SSB), and RACH timing (RO) are also signaled to the UE in the PDCCH. When the PDCCH triggers the UE to perform CBRA, the PRACH preamble, SSB, and RO are all determined by the UE. In CBRA, if the message (Msg4) in the fifth step is not received before the contention resolution timer at the UE expires, the UE ignores the TA in the message (Msg2) received in the third step.

[0126] As described above, in a conventional system, the UE cannot send PRACH on a deactivated SCell or monitor PDCCH on or for the deactivated SCell, nor can it send PRACH on a deactivated PSCell or monitor PDCCH on or for the deactivated PSCell.

[0127] In various aspects of the present disclosure, the UE may send a PRACH on the deactivated cell in order to perform a PRACH-based TA update for a TAG including the deactivated cell. The PRACH transmission may be part of a CFRA or a CBRA.

[0128] According to certain aspects of the present disclosure, the UE may monitor the PDCCH on or for the deactivated cell, and may receive the PDSCH on or for the deactivated cell, so that the UE can receive Msg2 of the RACH procedure as part of the PRACH-based TA update for the deactivated cell. The UE may send Msg3 of the RACH procedure to the deactivated cell, and the UE may receive Msg4 from the deactivated cell. In certain aspects of the present disclosure, the UE may be limited to activation or selection of a serving cell based on L1 or L2, for example, sending to and receiving from the deactivated cell only when the deactivated cell is a candidate SpCell for the UE.

[0129] Fig. 9An example call flow diagram 900 is depicted for communication in a network between a network entity (e.g., SpCell 902), a user equipment (UE) 904, and a candidate cell 906 for deactivating a cell. In some aspects, the network entity may be related to Figure 1 and Figure 3 BS 102 as depicted and described or relating to Figure 2 An example of a decomposed base station is depicted and described. Similarly, a UE may be for Figure 1 and Figure 3 The depicted and described example of a UE 104. However, in other aspects, the UE may be another type of wireless communication device and the network entity may be another type of network entity or network node, such as those described herein.

[0130] As illustrated, at 910, SpCell 902 may send a PDCCH to UE 904, the PDCCH instructing the UE to perform a PRACH-based TA update for candidate cell 906, which is a deactivated cell. At 912, in response to the PDCCH, the UE sends a PRACH to the candidate cell.

[0131] Among the technologies provided, Figure 8 Each of the messages in the five steps shown in may be transmitted to or received from the SpCell or the deactivation candidate PCell.

[0132] Fig.10 A table depicting five alternative techniques for performing TA update on a deactivated cell according to aspects of the present disclosure. In the table, SpCell refers to a special cell for a UE that is an active cell, and DCell refers to a deactivated cell for which TA update is to be performed. In a first alternative, a PDCCH ( Figure 8 The first step shown in FIG. 1 ) and the UE sends a PRACH to the deactivated cell ( Figure 8 In a first alternative, no Figure 8 The other steps shown in , and when the deactivated cell is activated, the TA for the deactivated cell is transmitted to the UE.

[0133] exist Fig.10 In the second alternative, the SpCell sends a PDCCH commanding the PRACH ( Figure 8 The first step shown in FIG. 1 ) and the UE sends a PRACH to the deactivated cell ( Figure 8Then, SpCell sends Msg2 ( Figure 8 Next, the UE sends Msg3 ( Figure 8 Finally, SpCell sends Msg4 ( Figure 8 5th step shown in ).

[0134] exist Fig.10 In the third alternative, the SpCell sends a PDCCH commanding the PRACH ( Figure 8 The first step shown in FIG. 1 ) and the UE sends a PRACH to the deactivated cell ( Figure 8 Then, the deactivated cell sends Msg2 ( Figure 8 Next, the UE sends Msg3 ( Figure 8 Finally, the deactivated cell sends Msg4 ( Figure 8 5th step shown in ).

[0135] exist Fig.10 In the fourth alternative, the PDCCH ( Figure 8 The first step shown in FIG. 1 ) and the UE sends a PRACH to the deactivated cell ( Figure 8 Then, the deactivated cell sends Msg2 ( Figure 8 Next, the UE sends Msg3 ( Figure 8 Finally, the deactivated cell sends Msg4 ( Figure 8 5th step shown in ).

[0136] exist Fig.10 In the fifth alternative, the PDCCH ( Figure 8 The first step shown in FIG. 1 ) and the UE sends a PRACH to the deactivated cell ( Figure 8 Then, SpCell sends Msg2 ( Figure 8 Next, the UE sends Msg3 ( Figure 8 Finally, SpCell sends Msg4 ( Figure 8 5th step shown in ).

[0137] In conventional technology, the UE transmits the PRACH of the PDCCH command on the active UL bandwidth part (BWP) using the PRACH transmit power, which is determined based on the parameters or reference signals (RS) configured for the active UL / DL BWP, as shown below. PRACH is transmitted on the active UL BWP. The target PRACH receive power is the same as the target receive power configured for the active UL BWP. When calculating the target receive power for PRACH, the path loss is calculated based on the PL RS and the transmit power for the PL RS. The PL RS is the DL RS associated with the PRACH transmission in the active DL BWP. However, for SSB, if the active DL BWP is the initial BWP with multiplexing mode 2 or 3, the DL RS may not be in the active DL BWP. The transmit power for the PL RS is the transmit power configured for the PL RS, for example, the transmit power configured for the SSB by the RRC parameter ss-PBCH-BlockPower and the transmit power configured for the CSI-RS by powerControlOffsetSS, except for the CFRA of the PDCCH command. For PDCCH-commanded CFRA, the transmit power for PL RS is the transmit power configured for the following items: One Quasi-Co-located (QCL) RS for the PDCCH Demodulation Reference Signal (DMRS) for the PDCCH command. If the TCI of the PDCCH has only one QCL RS, the transmit power of the QCL RS is used. If the TCI of the PDCCH has two QCL RSs, the transmit power of the QCL-Type D RS is used.

[0138] In aspects of the present disclosure, for PRACH transmissions on a deactivated cell, there is no active BWP, and therefore, PRACH power control parameter determination may be determined based on the corresponding DL BWP and UL BWP specified for the PRACH transmissions and the corresponding power control parameters.

[0139] In certain aspects of the present disclosure, the corresponding DL BWP and UL BWP may be determined by a rule. For example, the corresponding DL BWP and UL BWP determined by the power control parameters for deactivating the PRACH on the cell may be the initial DL BWP and ULBWP. Other example rules are: the corresponding DL BWP and UL BWP are provided by the RRC parameters firstActiveDownlinkBWP-ID and firstActiveUplinkBWP-Id, or the corresponding DL BWP and UL BWP are the DL BWP and UL BWP with the lowest BWP ID, or the corresponding DL BWP is the DL BWP with the lowest ID among the DL BWPs with SSB transmission, or the corresponding UL BWP is the UL BWP with the lowest ID among the UL BWPs with configured RACH opportunities.

[0140] In certain aspects of the present disclosure, the corresponding DL BWP and UL BWP may be indicated by the gNB via radio resource control (RRC) signaling, MAC-CE, or DCI.

[0141] In various aspects of the present disclosure, PRACH is sent by the UE on the determined UL BWP, regardless of whether the UL BWP is determined by rules or by instructions from the gNB.

[0142] In various aspects of the present disclosure, the target PRACH received power is the same as the target received power configured for the above-determined UL BWP, and the PL RS is the DL RS associated with the PRACH transmission in the determined DL BWP, regardless of whether the DL BWP is determined by a rule or by an indication from the gNB. As in conventional techniques, if the DL RS is an SSB, the SSB may not be in the determined DL BWP if the determined DL BWP is an initial BWP with multiplexing mode 2 or 3 specified in the 3GPP New Radio (NR) specification.

[0143] In various aspects of the present disclosure, if the DL RS is a CSI-RS, when determining a path loss to be used in PRACH power control parameter determination, the UE may measure only the CSI-RS within the determined DL BWP.

[0144] According to certain aspects of the present disclosure, when determining PRACH power control parameters, the transmit power for PLRS used in the determination may be the transmit power configured for PL RS, e.g., ss-PBCH-BlockPower for SSB and powerControlOffsetSS for CSI-RS, except for the CFRA commanded by the PDCCH. For the CFRA commanded by the PDCCH transmitted from the deactivated cell (e.g., Fig.10 The transmit power for the PL RS is the transmit power configured for the following items: One quasi-co-located (QCL) RS of the PDCCH demodulation reference signal (DMRS) for the PDCCH command. If the TCI of the PDCCH has only one QCL RS, the transmit power of the QCL RS is used. If the TCI of the PDCCH has two QCL RSs, the transmit power of the QCL-Type D RS is used. For PDCCH commands transmitted from the SpCell (e.g., Fig.10 The first alternative to the third alternative in the table in FIG. 2 ), the transmit power for PL RS used when the PRACH power control parameter is determined is the transmit power configured for PL RS, for example, the transmit power for SSB configured by the RRC parameter ss-PBCH-BlockPower and the transmit power for CSI-RS configured by powerControlOffsetSS.

[0145] In various aspects of the present disclosure, based on the Pc max,f,c The power control formula is used to determine the transmit power for PRACH. max,f,c is the maximum output power configured by the UE for deactivating the cell.

[0146] Fig.11 1 is an example timeline showing activities of a SpCell and a UE according to aspects of the present disclosure. In the timeline, a PDCCH is sent by the SpCell to command the UE to send a PRACH. As illustrated, after a minimum elapsed time, the UE sends a PRACH on the deactivated cell. The activities shown in the timeline are similar to those shown in FIG. Fig.10The first alternative to the third alternative shown in the table in matches. In various aspects of the present disclosure, for a PDCCH transmitted on a SpCell that commands a UE to send a PRACH on a deactivated cell, a minimum time between the PDCCH and the PRACH is defined to take into account the additional time for the UE to activate the UE's transmit chain. The minimum time may depend on the frequency range of the PRACH transmission, the DL and UL subcarrier spacing (SCS) of the SpCell and / or deactivated cell, and whether there is an UL transmission by the UE on another component carrier (CC) before the PRACH is to be sent.

[0147] In various aspects of the present disclosure, the minimum time between receiving PDCCH and sending PRACH on a deactivated cell may be determined by a fixed rule, by the capabilities of the UE, or by a mixture of the two, for example, some components used in the minimum time calculation may be determined according to a fixed rule, while other components used in the minimum time calculation may be determined according to the capabilities of the UE.

[0148] In conventional techniques, for a single cell or for carrier aggregation (CA) of carriers in the same frequency band, PRACH priority rules are used for PRACH transmitted on an active serving cell. Example PRACH priority rules include:

[0149] 1) It is not expected that a valid RACH opportunity (RO) overlaps with a DL symbol indicated by DCI format 2_0;

[0150] 2) If the PRACH transmission will overlap with any SSB symbol, the UE shall not perform PRACH transmission;

[0151] 3) If the PRACH transmission will overlap with any RRC configured DL symbol, the UE does not perform PRACH transmission;

[0152] 4) If the PRACH transmission will overlap with any RRC configured flexible symbol for which a DCI format 2_0 indicating the symbol type of the flexible symbol has not been detected, and the UE has not been provided with EnableConfiguredUL-r16 indicating the type of the flexible symbol, the UE does not perform PRACH transmission;

[0153] 5) If the PRACH transmission will overlap with the DL symbols or flexible symbols indicated by DCI format 2_0, the UE does not perform PRACH transmission;

[0154] 6) If the PRACH transmission will overlap with the DL symbols scheduled by the PDCCH, the UE does not perform PRACH transmission.

[0155] When PRACH and other signals or symbol types are on different CCs within the same frequency band, one or more of the above rules may apply.

[0156] According to aspects of the present disclosure, the PRACH priority rules described above may also be applied to a PRACH sent on a deactivated cell.

[0157] In conventional technology, the reception beam used by the UE to receive the Msg2 PDCCH and PDSCH caused by the PRACH in response to the PDCCH command may be determined according to the following rules:

[0158] 1) For a PDCCH command from a SpCell that triggers CFRA on the SpCell, if the PDSCH scheduling offset is longer than the duration used for QCL, the UE receives the Msg2 PDCCH using the PDCCH command receive beam, and the UE receives the Msg2 PDSCH using the SSB or CSI-RS associated with the PRACH.

[0159] 2) For a PDCCH command from SpCell triggering CFRA on SCell or a PDCCH command from SpCell triggering CBRA on SpCell, if the PDCCH scheduling offset is longer than the duration used for QCL, the UE uses the Type1-PDCCH common search space (CSS) receive beam to receive Msg2 PDCCH and PDSCH.

[0160] In various aspects of the present disclosure, for a PRACH sent by a UE on a deactivated cell, a reception beam and / or a transmission beam for Msg2, Msg3, and Msg4 associated with a PDCCH, PDSCH, PUSCH, or PUCCH may have various options. For example, according to a first option, the UE may use a reception beam of a PDCCH used to command PRACH transmission as a reception beam and / or a transmission beam for receiving or transmitting Msg2, Msg3, and Msg4. This option is applicable when the PDCCH command, Msg2, Msg3, and Msg4 are on the same cell, as described below. Fig. 12A As shown in Fig.10 The second alternative shown in the table and the fourth alternative shown in the table.

[0161] According to the second option, when the PDSCH scheduling offset is longer than the threshold "timeDurationforQCL", the UE may use the beam used to receive the SSB or CSI-RS associated with the PRACH as the transmit beam and / or receive beam for Msg2, Msg3 and Msg4. This option is applicable when PRACH, Msg2, Msg3 and Msg4 are on the same cell, as described below in Fig. 12B As shown in Fig.10 The third alternative shown in the table and the fourth alternative shown in the table.

[0162] According to the third option, when the PDSCH scheduling offset is longer than the threshold "timeDurationforQCL", the UE may use the Type1-PDCCH common search space (CSS) receive beam on the deactivated cell as the receive beam and / or transmit beam for Msg2, Msg3 and Msg4. This option is applicable to Fig.10 All alternatives shown in the table.

[0163] Fig. 12A An example scenario of selecting beams for receiving and transmitting Msg2, Msg3, and Msg4 (i.e., as described above) when the PDCCH commanding the PRACH transmission to deactivate the cell is on the same cell as Msg2, Msg3, and Msg4 according to various aspects of the present disclosure is illustrated. As illustrated, the PDCCH, Msg2, Msg3 (represented by Msg2), and Msg4 (also represented by Msg2) are all transmitted and received on the SpCell, so the UE uses the receive beam of the PDCCH commanding the PRACH transmission as the receive beam and transmit beam for receiving or transmitting Msg2, Msg3, and Msg4.

[0164] Fig. 12B Another example scenario of selecting beams for receiving and transmitting Msg2, Msg3, and Msg4 when PRACH transmission to a deactivated cell is on the same cell as Msg2, Msg3, and Msg4 (i.e., Option 2 above) according to various aspects of the present disclosure is illustrated. As illustrated, PRACH, Msg2, Msg3 (represented by Msg2), and Msg4 (also represented by Msg2) are all transmitted and received on the deactivated cell, so the UE uses the beam used for receiving the SSB or CSI-RS associated with the PRACH as the receive beam and transmit beam for Msg2, Msg3, and Msg4.

[0165] In various aspects of the present disclosure, if Msg2, Msg3, and Msg4 are received and sent on the deactivated cell (ie, Fig.10), the complexity of monitoring the corresponding PDCCH on the deactivated cell may be factored into the UE's limitation on the total monitored PDCCH candidates and non-overlapping CCEs per time slot across multiple DL CCs. The UE does not need to monitor more than a predetermined number of PDCCH candidates or more than a predetermined number of non-overlapping CCEs per time slot on the active DL BWPs of the scheduling cells from the activated cell and the deactivated cell. When the number of PDCCH candidates or the number of non-overlapping CCEs per time slot on the active DL BWPs of the scheduling cells from the activated cell and the deactivated cell exceeds a predetermined number, the UE may discard or ignore some PDCCH candidates or CCEs.

[0166] Example Operation of User Equipment

[0167] Fig.13 shows a method for use by a UE such as Figure 1 and Figure 3 An example of a method 1300 for UE 104 to perform wireless communications.

[0168] Method 1300 begins at step 1305: receiving a first instruction for sending a PRACH on a first cell that is deactivated. In some cases, the operation of this step refers to the following steps: Fig.15 The described circuits for receiving and / or codes for receiving may be or may be executed by the circuits and / or codes.

[0169] Method 1300 then proceeds to step 1310: sending the PRACH on the first cell in response to the first instruction. In some cases, the operation of this step refers to the following steps: Fig.15 The described circuits for transmitting and / or codes for transmitting, or may be executed by the circuits and / or the codes.

[0170] In some aspects, the method 1300 further includes receiving a TA for the first cell, wherein the TA is determined based on the PRACH. In some cases, the operation of this step refers to as described in reference Fig.15 The described circuits for receiving and / or codes for receiving may be or may be executed by the circuits and / or codes.

[0171] In some aspects, the method 1300 further includes using the TA to send a signal to the first cell. In some cases, the operation of this step refers to the Fig.15 The described circuits for transmitting and / or codes for transmitting, or may be executed by the circuits and / or the codes.

[0172] In some aspects, the first instruction is received from a SpCell; and the TA is received from the SpCell or the first cell.

[0173] In some aspects, the first instruction is received from the first cell; and the TA is received from the first cell or a SpCell.

[0174] In some aspects, at least one of the first command, the SSB, or the CSI-RS is received via a beam, and wherein the TA is received via the beam.

[0175] In some aspects, the method 1300 further includes sending an RRC connection request message via the beam. In some cases, the operation of this step refers to the Fig.15 The described circuits for transmitting and / or codes for transmitting, or may be executed by the circuits and / or the codes.

[0176] In some aspects, the method 1300 further includes receiving an RRC connection establishment message via the beam. In some cases, the operation of this step refers to the Fig.15 The described circuits for receiving and / or codes for receiving may be or may be executed by the circuits and / or codes.

[0177] In some aspects, the TA is received via a beam associated with a Type 1-PDCCH CSS.

[0178] In some aspects, the method 1300 further includes sending an RRC connection request message via the beam. In some cases, the operation of this step refers to the Fig.15 The described circuits for transmitting and / or codes for transmitting, or may be executed by the circuits and / or the codes.

[0179] In some aspects, the method 1300 further includes receiving an RRC connection establishment message via the beam. In some cases, the operation of this step refers to the Fig.15 The described circuits for receiving and / or codes for receiving may be or may be executed by the circuits and / or codes.

[0180] In some aspects, transmitting the PRACH includes transmitting the PRACH at a power level determined based on at least one of a first active UL BWP or a first active DL BWP of the UE.

[0181] In some aspects, the first active UL BWP is selected from a plurality of active UL BWPs, each UL BWP having a different BWP ID; the first active UL BWP has the lowest BWP ID among the different BWP IDs; and sending the PRACH on the first cell includes sending the PRACH on the first active UL BWP using a target received power equal to the target received power of the UL BWP.

[0182] In some aspects, the first active UL BWP is selected from a plurality of active UL BWPs having a configured RO, each UL BWP having a different BWP ID; the first active UL BWP has the lowest BWPID among these different BWP IDs; and sending the PRACH on the first cell includes: sending the PRACH on the first active UL BWP using a target received power equal to the target received power of the UL BWP.

[0183] In some aspects, the first active DL BWP is selected from a plurality of active DL BWPs, each DL BWP having a different BWP ID, and the first DL BWP has a lowest BWP ID among the different BWP IDs.

[0184] In some aspects, the first active DL BWP is selected from a plurality of active DL BWPs having SSBs, each DL BWP having a different BWP ID, and the first DL BWP has a lowest BWP ID among the different BWP IDs.

[0185] In some aspects, the at least one of the first active UL BWP or the first active DL BWP is indicated in a transmission received by the UE.

[0186] In some aspects, the power level is determined based on a PL associated with the first active DL BWP; and the PL is determined based on a CSI-RS transmitted within the first active DL BWP.

[0187] In some aspects, the first instruction is received from a SpCell.

[0188] In some aspects, the method 1300 further comprises determining a time period based on at least one of a frequency range of the first cell, a subcarrier spacing (SCS) of the SpCell, or an SCS of the first cell, wherein sending the PRACH comprises waiting for the time period after receiving the first instruction and then sending the PRACH. In some cases, the operation of this step refers to as described in reference Fig.15 The described circuits for determining and / or codes for determining may be performed by or may be executed by the circuits and / or the codes.

[0189] In some aspects, sending the PRACH includes sending the PRACH during a RO.

[0190] In some aspects, the method 1300 further comprises selecting the RO based on at least one of a DCI, a SSB, a DL symbol, or a flexible symbol. In some cases, the operation of this step refers to or may be performed by reference to Fig.15 The described circuits for selecting and / or codes for selecting are implemented.

[0191] In one aspect, method 1300 or any aspect related thereto may be performed by an apparatus such as Fig.15 The method 1300 is performed by a communication device 1500 that includes various components operable to, configured to, or adapted to perform the method 1300. The communication device 1500 is described in more detail below.

[0192] Please note that Fig.13 This is merely one example of a method, and other methods including fewer, additional, or alternative steps may also be consistent with the present disclosure.

[0193] Example Operations of Network Entities

[0194] Fig.14 shows a method for use by network entities such as Figure 1 and Figure 3 BS102 or as for Figure 2 An example of a method 1400 of performing wireless communications with a decomposed base station is discussed.

[0195] Method 1400 begins at step 1405: sending an instruction for causing the UE to send a PRACH on the deactivated first cell. In some cases, the operation of this step refers to the following steps: Fig.16 The described circuits for transmitting and / or codes for transmitting, or may be executed by the circuits and / or the codes.

[0196] Then, the method 1400 proceeds to step 1410: sending an indication of a TA for the first cell for the UE based on the PRACH. In some cases, the operation of this step refers to the following. Fig.16 The described circuits for transmitting and / or codes for transmitting, or may be executed by the circuits and / or the codes.

[0197] In some aspects, the instruction is sent via a SpCell; and the indication to the TA is sent via the SpCell or the first cell.

[0198] In some aspects, the instruction is sent via the first cell; and the indication to the TA is sent via the first cell or a SpCell.

[0199] In some aspects, at least one of the command, SSB, or CSI-RS is sent via a beam, and wherein the indication of the TA is sent via the beam.

[0200] In some aspects, the method 1400 further includes receiving an RRC connection request message via the beam. In some cases, the operation of this step refers to the Fig.16 The described circuits for receiving and / or codes for receiving may be or may be executed by the circuits and / or codes.

[0201] In some aspects, the method 1400 further includes sending an RRC connection establishment message via the beam. In some cases, the operation of this step refers to the Fig.16 The described circuits for transmitting and / or codes for transmitting, or may be executed by the circuits and / or the codes.

[0202] In some aspects, the indication of the TA is received via a beam associated with a Type 1-PDCCH CSS.

[0203] In some aspects, the method 1400 further includes receiving an RRC connection request message via the beam. In some cases, the operation of this step refers to the Fig.16 The described circuits for receiving and / or codes for receiving may be or may be executed by the circuits and / or codes.

[0204] In some aspects, the method 1400 further includes sending an RRC connection establishment message via the beam. In some cases, the operation of this step refers to the Fig.16 The described circuits for transmitting and / or codes for transmitting, or may be executed by the circuits and / or the codes.

[0205] In one aspect, method 1400 or any aspect related thereto may be performed by an apparatus such as Fig.16 The method 1400 is performed by a communication device 1600 that includes various components operable to, configured to, or adapted to perform the method 1400. The communication device 1600 is described in more detail below.

[0206] Please note that Fig.14 This is merely one example of a method, and other methods including fewer, additional, or alternative steps may also be consistent with the present disclosure.

[0207] Example Communication Device

[0208] Fig.15 Depicted are aspects of an example communications device 1500. In some aspects, communications device 1500 is a user equipment (UE), such as described above with respect to Figure 1 and Figure 3 UE 104 is described.

[0209] The communication device 1500 includes a processing system 1505 coupled to a transceiver 1565 (e.g., a transmitter and / or a receiver). The transceiver 1565 is configured to transmit and receive signals for the communication device 1500, such as the various signals described herein, via an antenna 1570. The processing system 1505 may be configured to perform processing functions for the communication device 1500, including processing signals received by the communication device 1500 and / or to be transmitted by it.

[0210] The processing system 1505 includes one or more processors 1510. In various aspects, the one or more processors 1510 may represent Figure 3 One or more of the receive processor 358, transmit processor 364, TX MIMO processor 366, and / or controller / processor 380 described herein. The one or more processors 1510 are coupled to the computer-readable medium / memory 1535 via bus 1560. In some aspects, the computer-readable medium / memory 1535 is configured to store instructions (e.g., computer-executable code) that, when executed by the one or more processors 1510, cause the one or more processors 1510 to perform operations for performing operations on the one or more processors 1510. Fig.13 The described method 1300 or any aspect related thereto. Note that references to a processor performing a function of the communication device 1500 may include one or more processors 1510 performing that function of the communication device 1500 .

[0211] In the depicted example, computer readable medium / memory 1535 stores code (e.g., executable instructions), such as code for receiving 1540, code for sending 1545, code for determining 1550, and code for selecting 1555. Processing of code for receiving 1540, code for sending 1545, code for determining 1550, and code for selecting 1555 may cause communication device 1500 to perform operations for Fig.13 The described method 1300 or any aspect related thereto.

[0212] The one or more processors 1510 include circuits configured to implement (e.g., execute) code stored in the computer-readable medium / memory 1535, including circuits such as circuits for receiving 1515, circuits for sending 1520, circuits for determining 1525, and circuits for selecting 1530. Processing by the circuits for receiving 1515, the circuits for sending 1520, the circuits for determining 1525, and the circuits for selecting 1530 may cause the communication device 1500 to perform operations for the communication device 1500. Fig.13 The described method 1300 or any aspect related thereto.

[0213] The various components of the communication device 1500 may be provided for performing Fig.13 The components of the described method 1300 or any aspect thereof. For example, the components for sending, transmitting, or outputting for sending may include Figure 3 The transceiver 354 and / or antenna 352 and / or Fig.15 The transceiver 1565 and antenna 1570 of the communication device 1500 in FIG. 1 may include Figure 3 The transceiver 354 and / or antenna 352 and / or Fig.15 The transceiver 1565 and antenna 1570 of the communication device 1500.

[0214] Fig.16 Aspects of an example communications device 1600 are depicted. In some aspects, communications device 1600 is a network entity such as Figure 1 and Figure 3 BS102 or as for Figure 2 The decomposed base station in question.

[0215] The communication device 1600 includes a processing system 1605 coupled to a transceiver 1645 (e.g., a transmitter and / or a receiver) and / or a network interface 1655. The transceiver 1645 is configured to transmit and receive signals for the communication device 1600 via an antenna 1650, such as various signals as described herein. The network interface 1655 is configured to transmit and receive signals for the communication device 1600 via a communication link (such as, for example, a signal such as described herein). Figure 2 The processing system 1605 may be configured to perform processing functions of the communication device 1600, including processing signals received by the communication device 1600 and / or to be transmitted by the communication device 1600.

[0216] The processing system 1605 includes one or more processors 1610. In various aspects, the one or more processors 1610 may represent Figure 3 One or more of the receive processor 338, transmit processor 320, TX MIMO processor 330, and / or controller / processor 340 described herein. The one or more processors 1610 are coupled to the computer readable medium / memory 1625 via the bus 1640. In some aspects, the computer readable medium / memory 1625 is configured to store instructions (e.g., computer executable code) that, when executed by the one or more processors 1610, cause the one or more processors 1610 to perform operations for Fig.14The method 1400 or any aspect related thereto is described. Note that references to a processor of the communication device 1600 that performs a function may include one or more processors 1610 of the communication device 1600 that perform that function.

[0217] In the depicted example, the computer readable medium / memory 1625 stores code (e.g., executable instructions), such as code 1630 for transmitting and code 1635 for receiving. Processing of the code 1630 for transmitting and the code 1635 for receiving may cause the communication device 1600 to perform operations for transmitting. Fig.14 The described method 1400 or any aspect related thereto.

[0218] The one or more processors 1610 include circuits configured to implement (e.g., execute) code stored in the computer-readable medium / memory 1625, including circuits such as circuits for transmitting 1615 and circuits for receiving 1620. Processing by the circuits for transmitting 1615 and the circuits for receiving 1620 may cause the communication device 1600 to perform operations such as for Fig.14 The described method 1400 or any aspect related thereto.

[0219] The various components of the communication device 1600 may be provided for performing Fig.14 The components of the described method 1400 or any aspect related thereto. The components for sending, transmitting, or outputting for sending may include Figure 3 The transceiver 332 and / or antenna 334 and / or Fig.16 The transceiver 1645 and antenna 1650 of the communication device 1600 in FIG. 1 may include Figure 3 The transceiver 332 and / or antenna 334 and / or Fig.16 The transceiver 1645 and antenna 1650 of the communication device 1600 in FIG.

[0220] Sample Clauses

[0221] Specific implementation examples are described in the following numbered clauses:

[0222] Clause 1: A method for wireless communications by a UE, the method comprising: receiving a first instruction to send a PRACH on a deactivated first cell; and sending the PRACH on the first cell in response to the first instruction.

[0223] Clause 2: The method of clause 1, further comprising: receiving a TA for the first cell, wherein the TA is determined based on the PRACH; and using the TA to send a signal to the first cell.

[0224] Clause 3: The method of clause 2, wherein the first instruction is received from a SpCell; and the TA is received from the SpCell or the first cell.

[0225] Clause 4: The method of clause 2, wherein the first instruction is received from the first cell; and the TA is received from the first cell or a SpCell.

[0226] Clause 5: A method according to clause 2, wherein at least one of the first command, SSB or CSI-RS is received via a beam, and wherein the TA is received via the beam, and the method further comprises: sending an RRC connection request message via the beam; and receiving an RRC connection establishment message via the beam.

[0227] Clause 6: A method according to clause 2, wherein the TA is received via a beam associated with a Type 1-PDCCH CSS, and the method further comprises: sending an RRC connection request message via the beam; and receiving an RRC connection establishment message via the beam.

[0228] Clause 7: A method as set forth in any of clauses 1 to 6, wherein sending the PRACH comprises sending the PRACH at a power level determined based on at least one of a first active UL BWP or a first active DL BWP of the UE.

[0229] Clause 8: A method according to clause 7, wherein the first active UL BWP is selected from a plurality of active UL BWPs, each UL BWP having a different BWP ID; the first active UL BWP has the lowest BWP ID among the different BWP IDs; and sending the PRACH on the first cell includes: sending the PRACH on the first active UL BWP using a target received power equal to the target received power of the UL BWP.

[0230] Clause 9: A method according to clause 7, wherein the first active UL BWP is selected from a plurality of active UL BWPs having a configured RO, each UL BWP having a different BWP ID; the first active UL BWP has the lowest BWP ID among the different BWP IDs; and sending the PRACH on the first cell includes: sending the PRACH on the first active UL BWP using a target received power equal to the target received power of the ULBWP.

[0231] Clause 10: The method of clause 7, wherein the first active DL BWP is selected from a plurality of active DL BWPs, each DL BWP having a different BWP ID, and the first DL BWP has a lowest BWP ID among the different BWP IDs.

[0232] Clause 11: The method of clause 7, wherein the first active DL BWP is selected from a plurality of active DL BWPs having SSBs, each DL BWP having a different BWP ID, and the first DL BWP has a lowest BWP ID among the different BWP IDs.

[0233] Clause 12: The method of clause 7, wherein the at least one of the first active UL BWP or the first active DL BWP is indicated in a transmission received by the UE.

[0234] Clause 13: The method of clause 7, wherein the power level is determined based on a PL associated with the first active DL BWP; and the PL is determined based on a CSI-RS transmitted within the first active DL BWP.

[0235] Clause 14: A method according to any one of clauses 1 to 3 or clauses 5 to 13, wherein the first instruction is received from a SpCell, and the method further comprises: determining a time period based on at least one of a frequency range of the first cell, an SCS of the SpCell, or an SCS of the first cell, wherein sending the PRACH comprises waiting for the time period after receiving the first instruction before sending the PRACH.

[0236] Clause 15: A method as described in any of clauses 1 to 14, wherein sending the PRACH comprises sending the PRACH during a RO, and the method further comprises: selecting the RO based on at least one of a DCI, an SSB, a DL symbol, or a flexible symbol.

[0237] Clause 16: A method for wireless communications by a network entity, the method comprising: sending an instruction for a UE to send a PRACH on a deactivated first cell; and sending an indication of a TA for the UE for the first cell based on the PRACH.

[0238] Clause 17: The method of clause 16, wherein the instruction is sent via a SpCell; and the indication to the TA is sent via the SpCell or the first cell.

[0239] Clause 18: A method as described in clause 16, wherein the instruction is sent via the first cell; and the indication to the TA is sent via the first cell or a SpCell.

[0240] Clause 19: A method according to any one of clauses 16 to 18, wherein at least one of a command, an SSB or a CSI-RS is sent via a beam, and wherein the indication of the TA is sent via the beam, and the method further comprises: receiving an RRC connection request message via the beam; and sending an RRC connection establishment message via the beam.

[0241] Clause 20: A method according to any one of clauses 16 to 19, wherein the indication of the TA is received via a beam associated with a Type 1-PDCCH CSS, and the method further comprises: receiving an RRC connection request message via the beam; and sending an RRC connection establishment message via the beam.

[0242] Clause 21: An apparatus, the apparatus comprising: a memory including executable instructions; and a processor configured to execute the executable instructions and cause the apparatus to perform the method according to any one of clauses 1 to 20.

[0243] Clause 22: An apparatus comprising means for performing the method according to any one of clauses 1 to 20.

[0244] Clause 23: A non-transitory computer readable medium comprising executable instructions which, when executed by a processor of an apparatus, cause the apparatus to perform the method of any one of clauses 1 to 20.

[0245] Clause 24: A computer program product embodied on a computer readable storage medium, the computer program product comprising code for performing the method according to any one of clauses 1 to 20.

[0246] Additional considerations

[0247] The foregoing description is provided to enable any person skilled in the art to practice the various aspects described herein. The examples discussed herein are not limited to the scope, applicability or aspects set forth in the claims. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. For example, without departing from the scope of the present disclosure, the functions and arrangements of the elements discussed may be changed. Various examples may ignore, replace or add various processes or components as appropriate. For example, the described methods may be performed in a different order than the described order, and various actions may be added, omitted or combined. In addition, the features described with respect to some examples may be combined in some other examples. For example, any number of aspects set forth herein may be used to implement a device or practice method. In addition, the scope of the present disclosure is intended to cover such devices or methods practiced using other structures, functionality, or structures and functionality that are supplementary or alternative to the various aspects of the present disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of the claims.

[0248] The various illustrative logical blocks, modules, and circuits described in conjunction with the present disclosure may be implemented or performed using a general purpose processor, a digital signal processor (DSP), an ASIC, a field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof, designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in an alternative, the processor may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, a system on a chip (SoC), or any other such configuration.

[0249] As used herein, a phrase referring to "at least one of" a list of items refers to any combination of those items (including single members). As an example, "at least one of a, b, or c" is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with multiple identical elements (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other ordering of a, b, and c).

[0250] As used herein, the term "determine" encompasses a wide variety of actions. For example, "determine" may include calculating, computing, processing, deriving, investigating, searching (e.g., searching in a table, a database, or another data structure), ascertaining, and the like. Furthermore, "determine" may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), and the like. Additionally, "determine" may include resolving, selecting, choosing, establishing, and the like.

[0251] The method disclosed herein includes one or more actions for implementing the method. The method actions may be interchangeable with each other without departing from the scope of the claims. In other words, unless a specific order of actions is specified, the order and / or use of specific actions may be modified without departing from the scope of the claims. In addition, the various operations of the method described above may be performed by any appropriate component capable of performing the corresponding function. The component may include various hardware and / or software components and / or modules, including but not limited to circuits, application specific integrated circuits (ASICs) or processors.

[0252] The following claims are not intended to be limited to the various aspects shown herein, but should be given the full scope consistent with the language of the claims. Within the claims, unless otherwise specified, reference to an element in the singular form is not intended to mean "one and only one", but "one or more". Unless otherwise specified, the term "some" refers to one or more. Any claim element is not interpreted according to the provisions of 35 U.S.C. § 112 (f) unless the element is explicitly stated using the phrase "parts for...". All structural and functional equivalents of the elements of the various aspects described throughout the present disclosure that are known or will be known later to a person of ordinary skill in the art are expressly incorporated herein by reference and are intended to be covered by the claims. In addition, nothing disclosed herein is intended to be dedicated to the public, regardless of whether such disclosure is explicitly stated in the claims.

Claims

1. A method for wireless communication by a user equipment (UE), the method comprising: receiving a first instruction for transmitting a physical random access channel (PRACH) on a deactivated first cell; as well as The PRACH is sent on the first cell in response to the first instruction.

2. The method according to claim 1, further comprising: receiving a timing advance (TA) for the first cell, wherein the TA is determined based on the PRACH; as well as The TA is used to send a signal to the first cell.

3. The method according to claim 2, wherein: The first instruction is received from a special cell (SpCell); and The TA is received from the SpCell or the first cell.

4. The method according to claim 2, wherein: The first instruction is received from the first cell; and The TA is received from the first cell or a special cell (SpCell).

5. The method of claim 1, wherein sending the PRACH comprises: The PRACH is transmitted at a power level determined based on at least one of a first active uplink (UL) bandwidth part (BWP) or a first active downlink (DL) BWP of the UE.

6. The method according to claim 5, wherein: The first active UL BWP is selected from a plurality of active UL BWPs, each UL BWP having a different BWP identifier (ID); The first active UL BWP has a lowest BWPID among the different BWP IDs; and Sending the PRACH on the first cell includes sending the PRACH on the first active UL BWP with a target received power equal to a target received power of the ULBWP.

7. The method according to claim 5, wherein: The first active UL BWP is selected from a plurality of active UL BWPs having a configured RACH opportunity (RO), each UL BWP having a different BWP identifier (ID); The first active UL BWP has a lowest BWPID among the different BWP IDs; and Sending the PRACH on the first cell includes sending the PRACH on the first active UL BWP with a target received power equal to a target received power of the ULBWP.

8. The method of claim 5, wherein the first active DL BWP is selected from a plurality of active DL BWPs, each DL BWP having a different BWP identifier (ID), and the first DL BWP has a lowest BWP ID among the different BWP IDs.

9. The method of claim 5, wherein the first active DL BWP is selected from a plurality of active DL BWPs having a synchronization signal block (SSB), each DL BWP having a different BWP identifier (ID), and the first DL BWP has a lowest BWP ID among the different BWP IDs.

10. The method of claim 5, wherein the at least one of the first active UL BWP or the first active DL BWP is indicated in a transmission received by the UE.

11. The method according to claim 5, wherein: The power level is determined based on a path loss (PL) associated with the first active DL BWP; and The PL is determined based on a channel state information reference signal (CSI-RS) transmitted within the first active DL BWP.

12. The method of claim 1, wherein the first instruction is received from a special cell (SpCell), and the method further comprises: The time period is determined based on at least one of the frequency range of the first cell, the subcarrier spacing (SCS) of the SpCell, or the SCS of the first cell, wherein sending the PRACH includes waiting for the time period before sending the PRACH after receiving the first instruction.

13. The method of claim 1 , wherein transmitting the PRACH comprises transmitting the PRACH during a RACH opportunity (RO), and the method further comprises: The RO is selected based on at least one of downlink control information (DCI), synchronization symbol blocks (SSBs), downlink (DL) symbols, or flexible symbols.

14. The method of claim 2, wherein at least one of a first command, a synchronization signal block (SSB), or a channel state information reference signal (CSI-RS) is received via a beam, and wherein the TA is received via the beam, and the method further comprises: sending a radio resource control (RRC) connection request message via the beam; as well as An RRC connection establishment message is received via the beam.

15. The method of claim 2, wherein the TA is received via a beam associated with a Type 1 Physical Downlink Control Channel (Type 1-PDCCH) Common Search Space (CSS), and the method further comprises: sending a radio resource control (RRC) connection request message via the beam; as well as An RRC connection establishment message is received via the beam.

16. A method for wireless communication by a network entity, the method comprising: sending an instruction for causing the UE to send a physical random access channel (PRACH) on the deactivated first cell; as well as An indication of a timing advance (TA) for the first cell for the UE is sent based on the PRACH.

17. The method of claim 16, wherein: The instruction is sent via a special cell (SpCell); and The indication of the TA is sent via the SpCell or the first cell.

18. The method of claim 16, wherein: The instruction is sent via the first cell, and The indication of the TA is sent via the first cell or a special cell (SpCell).

19. The method of claim 16, wherein at least one of a command, a synchronization signal block (SSB), or a channel state information reference signal (CSI-RS) is transmitted via a beam, and wherein the indication of the TA is transmitted via the beam, and the method further comprises: receiving a radio resource control (RRC) connection request message via the beam; as well as An RRC connection establishment message is sent via the beam.

20. The method of claim 16, wherein the indication of the TA is sent via a beam associated with a Type 1 Physical Downlink Control Channel (Type 1-PDCCH) Common Search Space (CSS), and the method further comprises: receiving a radio resource control (RRC) connection request message via the beam; as well as An RRC connection establishment message is sent via the beam.

21. A device, comprising: a memory including executable instructions; and a processor configured to execute the executable instructions and cause the apparatus to perform the method according to any one of claims 1 to 20.

22. An apparatus comprising means for performing the method according to any one of claims 1 to 20.

23. A non-transitory computer readable medium comprising executable instructions which, when executed by a processor of a device, cause the device to perform the method according to any one of claims 1 to 20.

24. A computer program product embodied on a computer readable storage medium, the computer readable storage medium comprising code for executing the method according to any one of claims 1 to 20.

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