WO2022061588A1

WO2022061588A1 - Standalone cell selection and reselection with channel bandwidth information

Info

Publication number: WO2022061588A1
Application number: PCT/CN2020/117155
Authority: WO
Inventors: Tianya LIN; Hao Zhang; Pan JIANG
Original assignee: Qualcomm Incorporated
Priority date: 2020-09-23
Filing date: 2020-09-23
Publication date: 2022-03-31

Abstract

A base station determines one or more channel bandwidths supported by a cell and broadcasts channel bandwidth information for the cell. A user equipment (UE) receives the channel bandwidth information for a first cell and determines, based on the channel bandwidth information, that a UE channel bandwidth is different than a channel bandwidth for the first cell. The UE excludes the first cell from cell selection or cell reselection for at least a period of time.

Description

STANDALONE CELL SELECTION AND RESELECTION WITH CHANNEL BANDWIDTH INFORMATION

BACKGROUND

Technical Field

The present disclosure relates generally to communication systems, and more particularly, to wireless communication including cell selection.

Introduction

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.

These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example telecommunication standard is 5G New Radio (NR) . 5G NR is part of a continuous mobile broadband evolution promulgated by Third Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with Internet of Things (IoT) ) , and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB) , massive machine type communications (mMTC) , and ultra-reliable low latency communications (URLLC) . Some aspects of 5G NR may be based on the 4G Long Term Evolution (LTE) standard. There exists a need for further improvements in 5G NR technology. These improvements may also be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.

SUMMARY

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication at a user equipment (UE) . The apparatus receives channel bandwidth information for a first cell and determines, based on the channel bandwidth information, that a UE channel bandwidth is different than a channel bandwidth for the first cell. The apparatus excludes the first cell from cell selection or cell reselection for at least a period of time.

In another aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication at a UE. The apparatus receives channel bandwidth information for one or more channel bandwidths supported by at least a first cell; compares the channel bandwidth information to channel bandwidth of the UE to determine whether the channel bandwidth of the UE matches one or more of the channel bandwidths supported by the first cell; and determines whether to include or exclude the first cell from cell selection or cell reselection for at least a period of time based on the comparison.

In another aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication at a base station. The apparatus determines one or more channel bandwidths supported by a cell and broadcasts channel bandwidth information for the cell.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network.

FIG. 2A is a diagram illustrating an example of a first frame, in accordance with various aspects of the present disclosure.

FIG. 2B is a diagram illustrating an example of DL channels within a subframe, in accordance with various aspects of the present disclosure.

FIG. 2C is a diagram illustrating an example of a second frame, in accordance with various aspects of the present disclosure.

FIG. 2D is a diagram illustrating an example of UL channels within a subframe, in accordance with various aspects of the present disclosure.

FIG. 3 is a diagram illustrating an example of a base station and user equipment (UE) in an access network.

FIGs. 4A and 4B illustrate examples of channel bandwidth information for a cell and a UE.

FIG. 5 is a communication flow between a UE and multiple cells including the UE using channel bandwidth information to exclude one or more cells from cell selection or reselection.

FIG. 6 is a flowchart of a method of wireless communication.

FIG. 7 is a diagram illustrating an example of a hardware implementation for an example apparatus.

FIG. 8 is a flowchart of a method of wireless communication.

FIG. 9 is a diagram illustrating an example of a hardware implementation for an example apparatus.

FIG. 10 is a flowchart of a method of wireless communication.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements” ) . These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

By way of example, an element, or any portion of an element, or any combination of elements may be implemented as a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs) , central processing units (CPUs) , application processors, digital signal processors (DSPs) , reduced instruction set computing (RISC) processors, systems on a chip (SoC) , baseband processors, field programmable gate arrays (FPGAs) , programmable logic devices (PLDs) , state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software. Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

Accordingly, in one or more example embodiments, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise a random-access memory (RAM) , a read-only memory (ROM) , an electrically erasable programmable ROM (EEPROM) , optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the aforementioned types of computer-readable media, or any other medium that can be used to store computer executable code in the form of instructions or data structures that can be accessed by a computer.

A UE may perform cell reselection and may consider one or more cells in order to select a cell or reselect to a new cell. The UE may receive system information for the cell (s) indicating a carrier bandwidth and/or an initial BWP bandwidth. After selecting the cell, and performing a registration process, the UE may determine that the channel bandwidths of the cell are not supported by the UE. For example, the network may broadcast supported channel bandwidth information in a radio resource control (RRC) reconfiguration message. The UE will determine that the cell does not support a channel bandwidth supported by the UE after camping on the cell. The network will then release an RRC connection for the UE, and the UE will perform cell selection to attempt to find a different cell.

Aspects presented herein enable a UE to more effectively select a cell through the network broadcasting channel bandwidth information as system information that the UE may use in performing cell selection or cell reselection. The UE may determine whether there is a match between the channel bandwidth (s) supported by a cell and the channel bandwidths supported by the UE. If there is no match, the UE may bar the cell, at least temporarily, from cell selection. This may help the UE to select a cell that supports the channel bandwidth of the UE and to avoid camping on a cell that does not support the UE’s channel bandwidth and RRC reconfiguration failure.

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network 100 that includes base stations 102 or 180 and UEs 104. In FIG. 1, a base station 102 or 180 may include a channel bandwidth component 199 that is configured to determine one or more channel bandwidths supported by a cell and to broadcast channel bandwidth information for the cell. For example, the channel bandwidth information may be broadcast in system information in order to assist UEs 104 in performing cell selection or cell reselection. For example, the channel bandwidth component 199 may be configured to indicate one or more downlink channel bandwidths and one or more uplink channel bandwidths that are supported by the cell. A UE 104 may include a cell selection component 198 configured to receive the channel bandwidth information for a first cell and to compare the channel bandwidth information to channel bandwidth of the UE to determine whether the channel bandwidth of the UE matches one or more of the channel bandwidths supported by the first cell. The cell selection component 198 may be configured to determine whether to include or exclude the first cell from cell selection or cell reselection for at least a period of time based on the comparison. For example, the cell selection component 198 may be configured to determine, based on the channel bandwidth information, that a UE channel bandwidth is different than a channel bandwidth for the first cell. The cell selection component 198 may be configured to exclude the first cell from cell selection or cell reselection, e.g., at least temporarily. In some examples, the cell selection component 198 may be configured to determine that the channel bandwidth of the UE matches at least one channel bandwidth supported by the cell and may include the cell in cell selection/reselection. Although the following description may be focused on 5G NR, the concepts described herein may be applicable to other similar areas, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

The wireless communications system (also referred to as a wireless wide area network (WWAN) ) includes base stations 102, UEs 104, an Evolved Packet Core (EPC) 160, and another core network 190 (e.g., a 5G Core (5GC) ) . The base stations 102 may include macrocells (high power cellular base station) and/or small cells (low power cellular base station) . The macrocells include base stations. The small cells include femtocells, picocells, and microcells.

The base stations 102 configured for 4G LTE (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN) ) may interface with the EPC 160 through first backhaul links 132 (e.g., S1 interface) . The base stations 102 configured for 5G NR (collectively referred to as Next Generation RAN (NG-RAN) ) may interface with core network 190 through second backhaul links 184. In addition to other functions, the base stations 102 may perform one or more of the following functions: transfer of user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity) , inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS) , subscriber and equipment trace, RAN information management (RIM) , paging, positioning, and delivery of warning messages. The base stations 102 may communicate directly or indirectly (e.g., through the EPC 160 or core network 190) with each other over third backhaul links 134 (e.g., X2 interface) . The first backhaul links 132, the second backhaul links 184, and the third backhaul links 134 may be wired or wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Each of the base stations 102 may provide communication coverage for a respective geographic coverage area 110. There may be overlapping geographic coverage areas 110. For example, the small cell 102' may have a coverage area 110' that overlaps the coverage area 110 of one or more macro base stations 102. A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include Home Evolved Node Bs (eNBs) (HeNBs) , which may provide service to a restricted group known as a closed subscriber group (CSG) . The communication links 120 between the base stations 102 and the UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to a base station 102 and/or downlink (DL) (also referred to as forward link) transmissions from a base station 102 to a UE 104. The communication links 120 may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links may be through one or more carriers. The base stations 102 /UEs 104 may use spectrum up to Y MHz (e.g., 5, 10, 15, 20, 100, 400, etc. MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers) used for transmission in each direction. The carriers may or may not be adjacent to each other. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL than for UL) . The component carriers may include a primary component carrier and one or more secondary component carriers. A primary component carrier may be referred to as a primary cell (PCell) and a secondary component carrier may be referred to as a secondary cell (SCell) .

Certain UEs 104 may communicate with each other using device-to-device (D2D) communication link 158. The D2D communication link 158 may use the DL/UL WWAN spectrum. 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) , and a physical sidelink control channel (PSCCH) . D2D communication may be through a variety of wireless D2D communications systems, such as for example, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.

The wireless communications system may further include a Wi-Fi access point (AP) 150 in communication with Wi-Fi stations (STAs) 152 via communication links 154, e.g., in a 5 GHz unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the STAs 152 /AP 150 may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

The small cell 102' may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell 102' may employ NR and use the same unlicensed frequency spectrum (e.g., 5 GHz, or the like) as used by the Wi-Fi AP 150. The small cell 102', employing NR in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network.

The electromagnetic spectrum is often subdivided, based on frequency/wavelength, into various classes, bands, channels, etc. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz –7.125 GHz) and FR2 (24.25 GHz –52.6 GHz) . The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to (interchangeably) as a “sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2, which is often referred to (interchangeably) as a “millimeter wave” band in documents and articles, despite being different from the extremely high frequency (EHF) band (30 GHz –300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band.

With the above aspects in mind, unless specifically stated otherwise, it should be understood that the term “sub-6 GHz” or the like if used herein may broadly represent frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Further, unless specifically stated otherwise, it should be understood that the term “millimeter wave” or the like if used herein may broadly represent frequencies that may include mid-band frequencies, may be within FR2, or may be within the EHF band.

A base station 102, whether a small cell 102' or a large cell (e.g., macro base station) , may include and/or be referred to as an eNB, gNodeB (gNB) , or another type of base station. Some base stations, such as gNB 180 may operate in a traditional sub 6 GHz spectrum, in millimeter wave frequencies, and/or near millimeter wave frequencies in communication with the UE 104. When the gNB 180 operates in millimeter wave or near millimeter wave frequencies, the gNB 180 may be referred to as a millimeter wave base station. The millimeter wave base station 180 may utilize beamforming 182 with the UE 104 to compensate for the path loss and short range. The base station 180 and the UE 104 may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate the beamforming.

The base station 180 may transmit a beamformed signal to the UE 104 in one or more transmit directions 182'. The UE 104 may receive the beamformed signal from the base station 180 in one or more receive directions 182”. The UE 104 may also transmit a beamformed signal to the base station 180 in one or more transmit directions. The base station 180 may receive the beamformed signal from the UE 104 in one or more receive directions. The base station 180 /UE 104 may perform beam training to determine the best receive and transmit directions for each of the base station 180 /UE 104. The transmit and receive directions for the base station 180 may or may not be the same. The transmit and receive directions for the UE 104 may or may not be the same.

The EPC 160 may include 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 a Packet Data Network (PDN) Gateway 172. The MME 162 may be in communication with a Home Subscriber Server (HSS) 174. The MME 162 is the control node that processes the signaling between the UEs 104 and the EPC 160. Generally, the MME 162 provides bearer and connection management. All user Internet protocol (IP) packets are transferred through the Serving Gateway 166, which itself is connected to the PDN Gateway 172. The PDN Gateway 172 provides UE IP address allocation as well as other functions. The PDN Gateway 172 and the BM-SC 170 are connected to the IP Services 176. The IP Services 176 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a PS Streaming Service, and/or other IP services. The BM-SC 170 may provide functions for MBMS user service provisioning and delivery. The BM-SC 170 may serve as an entry point for content provider MBMS transmission, may be used to authorize and initiate MBMS Bearer Services within a public land mobile network (PLMN) , and may be used to schedule MBMS transmissions. The MBMS Gateway 168 may be used to distribute MBMS traffic to the base stations 102 belonging to a Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a particular service, and may be responsible for session management (start/stop) and for collecting eMBMS related charging information.

The core network 190 may include an Access and Mobility Management Function (AMF) 192, other AMFs 193, a Session Management Function (SMF) 194, and a User Plane Function (UPF) 195. The AMF 192 may be in communication with a Unified Data Management (UDM) 196. The AMF 192 is the control node that processes the signaling between the UEs 104 and the core network 190. Generally, the AMF 192 provides QoS flow and session management. All user Internet protocol (IP) packets are transferred through the UPF 195. The UPF 195 provides UE IP address allocation as well as other functions. The UPF 195 is connected to the IP Services 197. The IP Services 197 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a Packet Switch (PS) Streaming (PSS) Service, and/or other IP services.

The base station may include and/or be referred to as a gNB, Node B, eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS) , an extended service set (ESS) , a transmit reception point (TRP) , or some other suitable terminology. The base station 102 provides an access point to the EPC 160 or core network 190 for a UE 104. Examples of UEs 104 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 (e.g., MP3 player) , a camera, a game console, a tablet, 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, or any other similar functioning device. Some of the UEs 104 may be referred to as IoT devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, etc. ) . The UE 104 may also be referred to as a station, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology.

FIG. 2A is a diagram 200 illustrating an example of a first subframe within a 5G NR frame structure. FIG. 2B is a diagram 230 illustrating an example of DL channels within a 5G NR subframe. FIG. 2C is a diagram 250 illustrating an example of a second subframe within a 5G NR frame structure. FIG. 2D is a diagram 280 illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplexed (FDD) in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for either DL or UL, or may be time division duplexed (TDD) in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for both DL and UL. In the examples provided by FIGs. 2A, 2C, the 5G NR frame structure is assumed to be TDD, with subframe 4 being configured with slot format 28 (with mostly DL) , where D is DL, U is UL, and F is flexible for use between DL/UL, and subframe 3 being configured with slot format 1 (with all UL) . While

subframes

3, 4 are shown with slot formats 1, 28, respectively, any particular subframe may be configured with any of the various available slot formats 0-61. Slot formats 0, 1 are all DL, UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. UEs are configured with the slot format (dynamically through DL control information (DCI) , or semi-statically/statically through radio resource control (RRC) signaling) through a received slot format indicator (SFI) . Note that the description infra applies also to a 5G NR frame structure that is TDD.

Other wireless communication technologies may have a different frame structure and/or different channels. A frame (10 ms) may be divided into 10 equally sized subframes (1 ms) . Each subframe may include one or more time slots. Subframes may also include mini-slots, which may include 7, 4, or 2 symbols. Each slot may include 7 or 14 symbols, depending on the slot configuration. For slot configuration 0, each slot may include 14 symbols, and for slot configuration 1, each slot may include 7 symbols. The symbols on DL may be cyclic prefix (CP) OFDM (CP-OFDM) symbols. The symbols on UL may be CP-OFDM symbols (for high throughput scenarios) or discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbols (also referred to as single carrier frequency-division multiple access (SC-FDMA) symbols) (for power limited scenarios; limited to a single stream transmission) . The number of slots within a subframe is based on the slot configuration and the numerology. For slot configuration 0, different numerologies μ 0 to 4 allow for 1, 2, 4, 8, and 16 slots, respectively, per subframe. For slot configuration 1, different numerologies 0 to 2 allow for 2, 4, and 8 slots, respectively, per subframe. Accordingly, for slot configuration 0 and numerology μ, there are 14 symbols/slot and 2 ^μ slots/subframe. The subcarrier spacing and symbol length/duration are a function of the numerology. The subcarrier spacing may be equal to 2 ^μ*15 kHz, where μ is the numerology 0 to 4. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=4 has a subcarrier spacing of 240 kHz. The symbol length/duration is inversely related to the subcarrier spacing. FIGs. 2A-2D provide an example of slot configuration 0 with 14 symbols per slot and numerology 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. Within a set of frames, there may be one or more different bandwidth parts (BWPs) (see FIG. 2B) that are frequency division multiplexed. Each BWP may have a particular numerology.

A resource grid may be used to represent the frame structure. Each time slot includes a resource block (RB) (also referred to as physical RBs (PRBs) ) that extends 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs) . The number of bits carried by each RE depends on the modulation scheme.

As illustrated in FIG. 2A, some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include demodulation RS (DM-RS) (indicated as R for one particular configuration, but other DM-RS configurations are possible) and channel state information reference signals (CSI-RS) for channel estimation at the UE. The RS may also include beam measurement RS (BRS) , beam refinement RS (BRRS) , and phase tracking RS (PT-RS) .

FIG. 2B illustrates an example of various DL channels within a subframe of a frame. The physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) (e.g., 1, 2, 4, 8, or 16 CCEs) , each CCE including six RE groups (REGs) , each REG including 12 consecutive REs in an OFDM symbol of an RB. A PDCCH within one BWP may be referred to as a control resource set (CORESET) . A UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., common search space, UE-specific search space) during PDCCH monitoring occasions on the CORESET, where the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs may be located at greater and/or lower frequencies across the channel bandwidth. A primary synchronization signal (PSS) may be within symbol 2 of particular subframes of a frame. The PSS is used by a UE 104 to determine subframe/symbol timing and a physical layer identity. A secondary synchronization signal (SSS) may be within symbol 4 of particular subframes of a frame. The SSS is used by a UE to determine a physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine a physical cell identifier (PCI) . Based on the PCI, the UE can determine the locations of the aforementioned DM-RS. The physical broadcast channel (PBCH) , which carries a master information block (MIB) , may be logically grouped with the PSS and SSS to form a synchronization signal (SS) /PBCH block (also referred to as SS block (SSB) ) . The MIB provides a number of RBs in the system bandwidth and a system frame number (SFN) . The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH such as system information blocks (SIBs) , and paging messages.

As illustrated in FIG. 2C, some of the REs carry DM-RS (indicated as R for one particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may transmit DM-RS for the physical uplink control channel (PUCCH) and DM-RS for the physical uplink shared channel (PUSCH) . The PUSCH DM-RS may be transmitted in the first one or two symbols of the PUSCH. The PUCCH DM-RS may be transmitted in different configurations depending on whether short or long PUCCHs are transmitted and depending on the particular PUCCH format used. The UE may transmit sounding reference signals (SRS) . The SRS may be transmitted in the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The SRS may be used by a base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

FIG. 2D illustrates an example of various UL channels within a subframe of a frame. The PUCCH may be located as indicated in one configuration. The PUCCH carries uplink control information (UCI) , such as scheduling requests, a channel quality indicator (CQI) , a precoding matrix indicator (PMI) , a rank indicator (RI) , and hybrid automatic repeat request (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.

FIG. 3 is a block diagram of a base station 310 in communication with a UE 350 in an access network. In the DL, IP packets from the EPC 160 may be provided to a controller/processor 375. The controller/processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The controller/processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIBs) , RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release) , inter radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression /decompression, security (ciphering, deciphering, integrity protection, integrity verification) , and handover support functions; RLC layer functionality associated with the transfer of upper layer packet data units (PDUs) , error correction through ARQ, concatenation, segmentation, and reassembly of RLC service data units (SDUs) , re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs) , demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

The transmit (TX) processor 316 and the receive (RX) processor 370 implement layer 1 functionality associated with various signal processing functions. Layer 1, which includes a physical (PHY) layer, may include error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, interleaving, rate matching, mapping onto physical channels, modulation/demodulation of physical channels, and MIMO antenna processing. The TX processor 316 handles mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK) , quadrature phase-shift keying (QPSK) , M-phase-shift keying (M-PSK) , M-quadrature amplitude modulation (M-QAM) ) . The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and/or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM stream is spatially precoded to produce multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the UE 350. Each spatial stream may then be provided to a different antenna 320 via a separate transmitter 318 TX. Each transmitter 318 TX may modulate an RF carrier with a respective spatial stream for transmission.

At the UE 350, each receiver 354 RX receives a signal through its respective antenna 352. Each receiver 354 RX recovers information modulated onto an RF carrier and provides the information to the receive (RX) processor 356. The TX processor 368 and the RX processor 356 implement layer 1 functionality associated with various signal processing functions. The RX processor 356 may perform spatial processing on the information to recover any spatial streams destined for the UE 350. If multiple spatial streams are destined for the UE 350, they may be combined by the RX processor 356 into a single OFDM symbol stream. The RX processor 356 then converts the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT) . The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the base station 310. These soft decisions may be based on channel estimates computed by the channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station 310 on the physical channel. The data and control signals are then provided to the controller/processor 359, which implements layer 3 and layer 2 functionality.

The controller/processor 359 can be associated with a memory 360 that stores program codes and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller/processor 359 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from the EPC 160. The controller/processor 359 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

Similar to the functionality described in connection with the DL transmission by the base station 310, the controller/processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIBs) acquisition, RRC connections, and measurement reporting; PDCP layer functionality associated with header compression /decompression, and security (ciphering, deciphering, integrity protection, integrity verification) ; RLC layer functionality associated with the transfer of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

Channel estimates derived by a channel estimator 358 from a reference signal or feedback transmitted by the base station 310 may be used by the TX processor 368 to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different antenna 352 via separate transmitters 354TX. Each transmitter 354TX may modulate an RF carrier with a respective spatial stream for transmission.

The UL transmission is processed at the base station 310 in a manner similar to that described in connection with the receiver function at the UE 350. Each receiver 318RX receives a signal through its respective antenna 320. Each receiver 318RX recovers information modulated onto an RF carrier and provides the information to a RX processor 370.

The controller/processor 375 can be associated with a memory 376 that stores program codes and data. The memory 376 may be referred to as a computer-readable medium. In the UL, the controller/processor 375 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE 350. IP packets from the controller/processor 375 may be provided to the EPC 160. The controller/processor 375 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

At least one of the TX processor 368, the RX processor 356, and the controller/processor 359 may be configured to perform aspects in connection with the cell selection component 198 of FIG. 1.

At least one of the TX processor 316, the RX processor 370, and the controller/processor 375 may be configured to perform aspects in connection with the channel bandwidth component 199 of FIG. 1.

As part of cell selection, or cell reselection, a UE may search for a suitable cell. Once the UE finds a suitable cell, the UE camps on the cell. The UE may use cell selection criteria, such as PLMN information for the cell, information from a NAS (such as whether the cell is barred, whether the cell is part of at least one tracking area (TA) that is not part of a forbidden tracking area list) , measurements of signal power from the cell, a service type of the cell, etc. For example, the UE may determine whether a transmitting power of the cell is strong enough to be detected by the UE, e.g., based on signal strength and/or quality criteria. After detecting a cell, the UE may decode system information, such as a MIB and/or SIB. The UE may determine whether a measured cell reception level (e.g., reference signal received power (RSRP) ) meets a threshold cell selection reception value and/or whether a measured cell quality (e.g., reference signal received quality (RSRQ) ) meets a threshold cell selection quality value.

Once the UE detects a suitable cell, the UE camps on the cell. For example, the UE may initiate a physical random access channel (PRACH) process. The UE may send a registration request to the network for the selected cell and may receive a registration response from the network. The UE may be triggered, at some point, to perform cell reselection. The UE may consider similar cell selection criteria in order to reselect to a different cell.

The UE may receive an indication of a carrier bandwidth and an initial bandwidth part (BWP) bandwidth for a cell (e.g., in a SIB such as SIB1) . The UE may camp on the cell if the supported channel bandwidth for the UE is between the two bandwidth numbers (e.g., the carrier bandwidth and the initial BWP bandwidth) . However, the UE is unaware of the channel bandwidth capability of the cell. In some examples, the cell may be an NR cell. The cell may support channel bandwidths that the UE cannot support.

FIG. 4A illustrates that a SIB 402 may provide information about a carrier bandwidth 404 and an initial BWP bandwidth 406. In FIG. 4A, the carrier bandwidth 404 is 30 MHz, and the initial BWP bandwidth 406 is 10 MHz. The channel bandwidth supported by the UE 412 is 20 MHZ, which is between 10 MHz (for the initial BWP bandwidth) and 30 MHz (for the carrier bandwidth) . Therefore, the UE may determine that the cell is a suitable cell during cell selection/cell reselection, at 414, and may camp on the cell. However, the channel bandwidths supported by the cell (e.g., 408 and 410) are 10 MHz and 30 MHz, neither of which matches/corresponds to the channel bandwidth supported by the UE.

After accessing and connecting to the cell, the UE may report a UE radio capability indicating the channel bandwidths supported by the UE. The UE may report one or more downlink channel bandwidths (e.g., channelBWs-DL” IE) and one or more uplink channel bandwidths (e.g., “channelBWs-UL” IE) supported by the UE. The UE may indicate the supported channel bandwidths per SCS and/or per frequency range (e.g., FR1, FR2, etc. ) . The base station may use the UE radio capability reported by the UE to determine a mismatch between the channel bandwidths supported by the base station and the channel bandwidths supported by the UE. In response to determining the mismatch, the base station may release the connection with the UE. For example, the UE within a coverage area of a standalone cell may report a measurement report (MR) to the network for a cell. After providing the MR to the network, it may be determined that the UE meets criteria for a reconfiguration failure (e.g., an RRC reconfiguration failure) , and the network may release an RRC connection with the UE. The RRC reconfiguration failure may be due to the mismatch between the supported channel bandwidths of the standalone cell (e.g., 10 MHz and 30 MHz as illustrated at 408 and 410) and the supported channel bandwidths of the UE (e.g., 20 MHz as illustrated at 412) .

The network may signal the channel bandwidth information to the UE after the UE camps on the cell. As an example, the network may broadcast channel bandwidths in an RRC reconfiguration message. For example, the channel bandwidth of the cell per subcarrier spacing (SCS) may be signaled to the UE in an RRC reconfiguration message (e.g., an “RRCReconfiguration” ) , as a list of supported downlink channel bandwidth per SCS for the cell (e.g., in a “downlinkChannelBW-PerSCS-List” information element (IE) ) and a list of uplink channel bandwidths per SCS supported by the cell (e.g., in an “uplinkChannelBW-PerSCS-List” IE) . The UE may only determine after RRC Reconfiguration message is received that the cell does not support a channel bandwidth supported by the UE (e.g., 412) .

As illustrated by the SIB 402 in FIG. 4A, the network may broadcast a SIB (e.g., SIB1) indicating the carrier bandwidth and the initial BWP bandwidth. The present disclosure provides for the network to provide channel bandwidth information in system information, e.g., before the RRC reconfiguration and before the UE camps on the cell. FIG. 4B illustrates an example in which the information about supported channel bandwidths of a cell (e.g., 408 and 410) are provided in system information (e.g., a SIB such as SIB1) in addition to the carrier bandwidth 404 and the initial BWP bandwidth 406. The channel bandwidth information in the SIB enables the UE to identify the channel bandwidth mismatch (e.g., that the cell does not support a channel bandwidth supported by the UE) before performing cell selection. As illustrated at 416, the UE may exclude (e.g., bar) the cell from cell selection and may select another cell (e.g., a cell that does support a channel bandwidth supported by the UE) .

The UE may use the channel bandwidth information received in system information from the network to avoid camping on a cell having mismatched channel bandwidths with the bandwidth (s) supported by the UE and to camp on a cell that supports a channel bandwidth that corresponds to a channel bandwidth supported by the UE. The information helps to improve the probability that the UE will select to a standalone cell that supports a channel bandwidth supports by the UE, e.g., by enabling the UE to bar from reselection at least some of the cells that have a channel bandwidth mismatch with the UE. The channel bandwidth information provided in system information may help the UE to avoid an RRC release from the network during the registration process, the release being due to the UE not supporting a channel bandwidth supported by the network.

FIG. 5 illustrates an example communication flow between a UE 502 and a

network including cells

504a, 504b, and 504c. The

cells

504a, 504, and 504c may be standalone cells. In some examples, the cells may be NR standalone cells. Aspects may also be applied to cells of other RATs. The UE 502 receives channel bandwidth information 503 from a first cell 504a in system information, such as a SIB. The UE 502 may further receive channel bandwidth information 507 and/or 511 from

cells

504b and 504c. The

channel bandwidth information

503, 507, and/or 511 may include a list of supported downlink channel bandwidths per SCS and/or a list of supported uplink channel bandwidths per SCS, for example. In addition to the

channel bandwidth information

503, 507, or 511, the UE may receive an indication of a carrier bandwidth and

initial BWP bandwidth

505, 509, 513 in system information from the respective cell 504a-c. The carrier bandwidth and initial BWP may also be provided in a SIB, e.g., SIB 1, which may be the same bandwidth as the

channel bandwidth information

503, 507, 511.

At 515, the UE 502 may compare the channel bandwidth (s) supported by the UE 502 to the channel bandwidths supported by a cell in order to determine whether there is a channel bandwidth match in which the cell and UE support the same channel bandwidth or a channel bandwidth mismatch in which the cell does not support any channel bandwidth supported by the UE.

If the UE channel bandwidth is not equal to any channel bandwidths of a cell (e.g., cell 504a) , the UE bars the cell (e.g., 504a) from selection/reselection, at 517. The supported channel bandwidths for a cell may change over time. Thus, the UE 502 may bar the cell 504a from selection/reselection for a certain time. Additionally, or alternatively, the UE 502 may select/reselect another cell, at 519. For example, the UE may select/reselect to another channel bandwidth matched cell. For example, in FIG. 5, the UE 502 may determine that the cell 504a does not support any channel bandwidth that is supported by the UE and may exclude/bar the cell 504a from cell selection/reselection. In another example, the UE 502 may select a different cell 504b, e.g., a cell that supports a matching channel bandwidth. After selecting the cell 504b, the UE 502 may camp on the cell 504b. Based on camping on the cell 504b, the UE may transmit a registration request 521 and may receive a registration accept message 523 from the cell 504b.

Although not illustrated, the UE may stop barring the cell 504a from selection/reselection after a period of time. The period of time may be configurable. As one non-limiting example, the period of time may be a few minutes. After the period of time, the UE may include the cell 504a in cell selection/reselection. In some examples, after the period of time, the UE may check the system information of the cell 504a to determine whether there has been a change and the cell supports a channel bandwidth that is also supported by the UE. In some examples, after the period of time, the UE may drop the cell 504a from a barred list. In some examples, after the period of time, the UE may assume that the cell 504a supports a channel bandwidth of the UE.

Aspects presented herein enable a UE to more effectively select a cell through the network broadcasting channel bandwidth information as system information that the UE may use in performing cell selection or cell reselection. The UE may determine whether there is a match between the channel bandwidth (s) supported by a cell and the channel bandwidths supported by the UE. If there is no match, the UE may bar the cell, at least temporarily, from cell selection. This may help the UE to select a cell that supports the channel bandwidth of the UE and to avoid camping on a cell that does not support the UE’s channel bandwidth.

FIG. 6 is a flowchart 600 of a method of wireless communication. The method may be performed by a UE (e.g., the

UE

104, 350, 502; the apparatus 702) . Optional aspects are illustrated with a dashed line. The method may help the UE to more effectively select a cell. The method may enable the base station to avoid signaling to establish a connection with a cell that does not support the channel bandwidth of the UE.

At 602, the UE receives channel bandwidth information for a first cell. The reception may be performed, e.g., by the channel bandwidth information component 740 of the apparatus 702 in FIG. 7. The UE receives the channel bandwidth information for the first cell before establishing an RRC connection with the first cell. The UE may receive the channel bandwidth information for the cell in system information, e.g., as a broadcast in a SIB such as SIB1. The UE may receive the channel bandwidth information for the cell in addition to a carrier bandwidth and initial BWP bandwidth for the cell. The channel bandwidth information for the cell may include one or more downlink channel bandwidth and one or more uplink channel bandwidth for the cell. The one or more downlink channel bandwidth may be indicated per SCS (e.g., in a downlink channel BW per SCS list) , and the one or more uplink channel bandwidth may be indicated per SCS (e.g., in an uplink downlink channel BW per SCS list) . FIG. 5 illustrates a UE 502 receiving channel bandwidth information from one or more cells.

At 604, the UE determines, based on the channel bandwidth information, that a UE channel bandwidth is different than a channel bandwidth for the first cell. The determination may be performed, e.g., by the match component 742 of the apparatus 702 in FIG. 7. For example, none of the supported channel bandwidths indicated for the cell may match or correspond to a channel bandwidth supported by the UE. The lack of a match may also be referred to as mismatch between the supported channel bandwidths of the UE and the cell. FIG. 5 illustrates a UE comparing the channel bandwidth information for a cell to the channel bandwidth of the UE, at 515, which may be performed as part of the determination at 604.

At 606, the UE excludes the first cell from cell selection or cell reselection for at least a period of time. The UE may bar selection/reselection to the cell, or may consider other cells for cell selection or cell reselection. The exclusion may be performed, e.g., by the exclusion/inclusion component 744 of the apparatus 702 in FIG. 7. The channel bandwidths supported by a cell may change over time. Therefore, the UE may exclude the cell temporarily, e.g., for a period of time following receipt of the system information indicating the channel bandwidth information for the cell.

As illustrated at 608, the UE may receive the channel bandwidth information for a second cell. The reception may be performed, e.g., by the channel bandwidth information component 740 of the apparatus 702 in FIG. 7. FIG. 5 illustrates a UE 502 receiving channel bandwidth information from multiple cells.

The UE may determine that the UE channel bandwidth corresponds to a matching channel bandwidth for the second cell, at 610. The determination may be performed, e.g., by the match component 742 of the apparatus 702 in FIG. 7. The comparison described in connection with 515 may be performed for multiple cells, for example.

As illustrated at 612, the UE may include the second cell in the cell selection or the cell reselection. The inclusion may be performed, e.g., by the exclusion/inclusion component 744 of the apparatus 702 in FIG. 7. The UE may proceed to perform cell selection/reselection, such as described in connection with 519 in FIG. 5. The cell selection/reselection may be performed, e.g., by the cell selection component 748 of the apparatus 702 in FIG. 7. The UE may then send a registration request to one of the cells included in the selection/reselection process. The method of FIG. 6 may help the UE to select to a cell that supports a channel bandwidth of the UE.

FIG. 10 is a flowchart 1000 of another example method of wireless communication. The method may be performed by a UE (e.g., the

UE

At 1002, the UE receives channel bandwidth information for a first cell. The reception may be performed, e.g., by the channel bandwidth information component 740 of the apparatus 702 in FIG. 7. The UE receives the channel bandwidth information for the first cell before establishing an RRC connection with the first cell. The UE may receive the channel bandwidth information for the cell in system information, e.g., as a broadcast in a SIB such as SIB1. The UE may receive the channel bandwidth information for the cell in addition to a carrier bandwidth and initial BWP bandwidth for the cell. The channel bandwidth information for the cell may include one or more downlink channel bandwidth and one or more uplink channel bandwidth for the cell. The one or more downlink channel bandwidth may be indicated per SCS (e.g., in a downlink channel BW per SCS list) , and the one or more uplink channel bandwidth may be indicated per SCS (e.g., in an uplink downlink channel BW per SCS list) . FIG. 5 illustrates a UE 502 receiving channel bandwidth information from one or more cells.

At 1004, the UE compares the channel bandwidth information to channel bandwidth of the UE to determine whether the channel bandwidth of the UE matches one or more of the channel bandwidths supported by the first cell. The determination may be performed, e.g., by the match component 742 of the apparatus 702 in FIG. 7. FIG. 5 illustrates a UE comparing the channel bandwidth information for a cell to the channel bandwidth of the UE, at 515, which may be performed as part of the determination at 604.

At 1006, the UE determines whether to include or exclude the first cell from cell selection or cell reselection for at least a period of time based on the comparison. The determination may be performed, e.g., by the exclusion/inclusion component 744 of the apparatus 702. For, example, the UE may determine whether to include or exclude the first cell from the cell selection or the cell reselection based on the comparison that the channel bandwidth of the UE is different than the one or more channel bandwidths supported by the first cell.

As illustrated at 1008, the UE may exclude the first cell from the cell selection or the cell reselection if the channel bandwidth of the UE is different than the one or more channel bandwidths supported by the first cell.

As illustrated at 1010, the UE may include the first cell from the cell selection or the cell reselection if the channel bandwidth of the UE matches at least one channel bandwidth supported by the first cell.

FIG. 7 is a diagram 700 illustrating an example of a hardware implementation for an apparatus 702. The apparatus 702 is a UE and includes a cellular baseband processor 704 (also referred to as a modem) coupled to a cellular RF transceiver 722 and one or more subscriber identity modules (SIM) cards 720, an application processor 706 coupled to a secure digital (SD) card 708 and a screen 710, a Bluetooth module 712, a wireless local area network (WLAN) module 714, a Global Positioning System (GPS) module 716, and a power supply 718. The cellular baseband processor 704 communicates through the cellular RF transceiver 722 with the UE 104 and/or BS 102/180. The cellular baseband processor 704 may include a computer-readable medium /memory. The computer-readable medium /memory may be non-transitory. The cellular baseband processor 704 is responsible for general processing, including the execution of software stored on the computer-readable medium /memory. The software, when executed by the cellular baseband processor 704, causes the cellular baseband processor 704 to perform the various functions described supra. The computer-readable medium /memory may also be used for storing data that is manipulated by the cellular baseband processor 704 when executing software. The cellular baseband processor 704 further includes a reception component 730, a communication manager 732, and a transmission component 734. The communication manager 732 includes the one or more illustrated components. The components within the communication manager 732 may be stored in the computer-readable medium /memory and/or configured as hardware within the cellular baseband processor 704. The cellular baseband processor 704 may be a component of the UE 350 and may include the memory 360 and/or at least one of the TX processor 368, the RX processor 356, and the controller/processor 359. In one configuration, the apparatus 702 may be a modem chip and include just the baseband processor 704, and in another configuration, the apparatus 702 may be the entire UE (e.g., see 350 of FIG. 3) and include the additional modules of the apparatus 702.

The communication manager 732 includes a channel bandwidth information component 740 that is configured to receive channel bandwidth information for at least one cell, e.g., as described in connection with 602 and/or 608 in FIG. 6. The communication manager 732 further includes a match component 742 that is configured to determine, based on the channel bandwidth information, that a channel bandwidth is different than a channel bandwidth for a first cell, e.g., as described in connection with 604 in FIG. 6. The match component 742 may be further configured to determine that the UE channel bandwidth corresponds to a matching channel bandwidth for the second cell, e.g., as described in connection with 610. The communication manager 732 further includes an exclusion/inclusion component 744 that is configured to exclude the first cell from cell selection/reselection for at least a period of time, e.g., as described in connection with 606 in FIG. 6. The exclusion/inclusion component 744 may be configured to include the second cell in the cell selection or the cell reselection. The communication manager 732 may further include a cell selection component 746 that is configured to perform cell selection/cell reselection, e.g., based on the included cells having matching channel bandwidths to the UE channel bandwidth.

The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowchart of FIG. 6 and/or the aspects performed by the UE in the communication flow in FIG. 5. As such, each block in the aforementioned flowchart of FIG. 6 and/or the aspects performed by the UE in the communication flow in FIG. 5 may be performed by a component and the apparatus may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof.

In one configuration, the apparatus 702, and in particular the cellular baseband processor 704, includes means for receiving channel bandwidth information for a first cell and means for determining, based on the channel bandwidth information, that a UE channel bandwidth is different than a channel bandwidth for the first cell. The apparatus further includes means for excluding the first cell from cell selection or cell reselection for at least a period of time. The means for receiving may be further configured to receive the channel bandwidth information for a second cell, and the means for determining may be further configured to determine that the UE channel bandwidth corresponds to a matching channel bandwidth for the second cell. The apparatus may include means for including the second cell in the cell selection or the cell reselection. The aforementioned means may be one or more of the aforementioned components of the apparatus 702 configured to perform the functions recited by the aforementioned means. As described supra, the apparatus 702 may include the TX Processor 368, the RX Processor 356, and the controller/processor 359. As such, in one configuration, the aforementioned means may be the TX Processor 368, the RX Processor 356, and the controller/processor 359 configured to perform the functions recited by the aforementioned means.

FIG. 8 is a flowchart 800 of a method of wireless communication. The method may be performed by a base station (e.g., the

base station

102, 180, 310;

cell

504a, 504b, 504c; the apparatus 902. The method may enable the base station to provide information for UEs to more effectively perform cell selection and to reduce signaling overhead to establish a connection with UEs that have channel bandwidths that are not supported by the base station.

At 802, the base station determines one or more channel bandwidths supported by a cell. The determination may be performed, e.g., by the channel bandwidth information component 940 of the apparatus 902 in FIG. 9. The base station may determine one or more downlink channel bandwidths and/or one or more uplink channel bandwidths supported by the cell. The supported channel bandwidths may be per SCS, in some examples. The channel bandwidths supported by the cell may change over time.

At 804, the base station broadcasts channel bandwidth information for the cell. The broadcast may be performed, e.g., by the system information component 942 of the apparatus 902 in FIG. 9. The base station broadcasts the channel bandwidth information, e.g., prior to establishing an RRC connection with a UE so that the UE may use the information to assist in cell selection. The base station may broadcast the channel bandwidth information for the cell is in system information, e.g., in a SIB such as SIB1. In some examples, the base station may broadcast the channel bandwidth information in another message, e.g., prior to the RRC connection with the UE. The base station may broadcast the channel bandwidth information for the cell in addition to a carrier bandwidth and initial BWP bandwidth for the cell. The channel bandwidth information for the cell may include one or more downlink channel bandwidth and one or more uplink channel bandwidth for the cell. The one or more downlink channel bandwidth may be indicated per SCS (e.g., in a downlink channel BW per SCS list) , and the one or more uplink channel bandwidth may be indicated per SCS (e.g., in an uplink downlink channel BW per SCS list) . FIG. 5 illustrates examples of cells broadcasting channel bandwidth information.

FIG. 9 is a diagram 900 illustrating an example of a hardware implementation for an apparatus 902. The apparatus 902 may be a base station or a component of a base station and includes a baseband unit 904. The baseband unit 904 may communicate through a cellular RF transceiver with the UE 104. The baseband unit 904 may include a computer-readable medium /memory. The baseband unit 904 is responsible for general processing, including the execution of software stored on the computer-readable medium /memory. The software, when executed by the baseband unit 904, causes the baseband unit 904 to perform the various functions described supra. The computer-readable medium /memory may also be used for storing data that is manipulated by the baseband unit 904 when executing software. The baseband unit 904 further includes a reception component 930, a communication manager 932, and a transmission component 934. The communication manager 932 includes the one or more illustrated components. The components within the communication manager 932 may be stored in the computer-readable medium /memory and/or configured as hardware within the baseband unit 904. The baseband unit 904 may be a component of the BS 310 and may include the memory 376 and/or at least one of the TX processor 316, the RX processor 370, and the controller/processor 375.

The communication manager 932 includes a channel bandwidth information component 940 that is configured to determine one or more channel bandwidths supported by a cell, e.g., as described in connection with 802 in FIG. 8. The communication manager 932 further includes a system information component 942 that is configured to broadcast channel bandwidth information for the cell, e.g., as described in connection with 804 in FIG. 8. The communication manager 932 may further includes a carrier bandwidth component 944 and/or an initial BWP component 946 that determines the carrier bandwidth or initial BWP that may be provided in the system information in addition to the channel bandwidth information, e.g., as described in connection with FIG. 5.

The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowchart of FIG. 8 and/or the aspects performed by one or more of the cells in the communication flow in FIG. 5. As such, each block in the aforementioned flowchart of FIG. 8 and/or the aspects performed by one or more of the cells in the communication flow in FIG. 5 may be performed by a component and the apparatus may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof.

In one configuration, the apparatus 902, and in particular the baseband unit 904, includes means for determining one or more channel bandwidths supported by a cell; and means for broadcasting channel bandwidth information for the cell. The aforementioned means may be one or more of the aforementioned components of the apparatus 902 configured to perform the functions recited by the aforementioned means. As described supra, the apparatus 902 may include the TX Processor 316, the RX Processor 370, and the controller/processor 375. As such, in one configuration, the aforementioned means may be the TX Processor 316, the RX Processor 370, and the controller/processor 375 configured to perform the functions recited by the aforementioned means.

It is understood that the specific order or hierarchy of blocks in the processes /flowcharts disclosed is an illustration of example approaches. Based upon design preferences, it is understood that the specific order or hierarchy of blocks in the processes /flowcharts may be rearranged. Further, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

The following examples are illustrative only and may be combined with aspects of other embodiments or teachings described herein, without limitation.

Example 1 is a method of wireless communication at a UE, comprising: receiving channel bandwidth information for a first cell; determining, based on the channel bandwidth information, that a UE channel bandwidth is different than a channel bandwidth for the first cell; and excluding the first cell from cell selection or cell reselection for at least a period of time.

In Example 2, the method of any Example 1 further includes that the channel bandwidth information for the first cell is received in system information.

In Example 3, the method of Example 1 or Example 2 further includes that the channel bandwidth information for the first cell is received in a system information block (SIB) .

In Example 4, the method of any of Examples 1-3 further includes that the channel bandwidth information for the first cell is received in addition to a carrier bandwidth and initial BWP bandwidth for the first cell.

In Example 5, the method of any of Examples 1-4 further includes that the channel bandwidth information for the first cell includes one or more downlink channel bandwidth and one or more uplink channel bandwidth for the first cell.

In Example 6, the method of any of Examples 1-5 further includes that the one or more downlink channel bandwidth is indicated per SCS, and the one or more uplink channel bandwidth is indicated per SCS.

In Example 7, the method of any of Examples 1-6 further includes receiving the channel bandwidth information for a second cell; determining that the UE channel bandwidth corresponds to a matching channel bandwidth for the second cell; and including the second cell in the cell selection or the cell reselection.

Example 8 is a device including one or more processors and one or more memories in electronic communication with the one or more processors storing instructions executable by the one or more processors to cause the device to implement a method as in any of Examples 1-7.

Example 9 is a system or apparatus including means for implementing a method or realizing an apparatus as in any of Examples 1-7.

Example 10 is a non-transitory computer readable medium storing instructions executable by one or more processors to cause the one or more processors to implement a method as in any of Examples 1-7.

Example 11 is a method of wireless communication at a base station, comprising: determining one or more channel bandwidths supported by a cell; and channel bandwidth information for the cell.

In Example 12, the method of Example 11 further includes that the base station transmits the channel bandwidth information for the cell in system information.

In Example 13, the method of Example 11 or Example 12 further includes that the channel bandwidth information for the cell is transmitted in a SIB.

In Example 14, the method of any of Examples 11-13 further includes that the channel bandwidth information for the cell is broadcast in addition to a carrier bandwidth and initial BWP bandwidth for the cell.

In Example 15, the method of any of Examples 11-14 further includes that the channel bandwidth information for the cell includes one or more downlink channel bandwidth and one or more uplink channel bandwidth for the cell.

In Example 16, the method of any of Examples 11-15 further includes that the one or more downlink channel bandwidth is indicated per SCS, and the one or more uplink channel bandwidth is indicated per SCS.

Example 17 is a device including one or more processors and one or more memories in electronic communication with the one or more processors storing instructions executable by the one or more processors to cause the device to implement a method as in any of Examples 11-16.

Example 18 is a system or apparatus including means for implementing a method or realizing an apparatus as in any of Examples 11-16.

Example 19 is a non-transitory computer readable medium storing instructions executable by one or more processors to cause the one or more processors to implement a method as in any of Examples 11-16.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” Terms such as “if, ” “when, ” and “while” should be interpreted to mean “under the condition that” rather than imply an immediate temporal relationship or reaction. That is, these phrases, e.g., “when, ” do not imply an immediate action in response to or during the occurrence of an action, but simply imply that if a condition is met then an action will occur, but without requiring a specific or immediate time constraint for the action to occur. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module, ” “mechanism, ” “element, ” “device, ” and the like may not be a substitute for the word “means. ” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for. ”

Claims

A method of wireless communication at a user equipment (UE) , comprising:

receiving channel bandwidth information for a first cell;

determining, based on the channel bandwidth information, that a UE channel bandwidth is different than a channel bandwidth for the first cell; and

excluding the first cell from cell selection or cell reselection for at least a period of time.
The method of claim 1, wherein the channel bandwidth information for the first cell is received in system information.
The method of claim 2, wherein the channel bandwidth information for the first cell is received in a system information block (SIB) .
The method of claim 1, wherein the channel bandwidth information for the first cell is received in addition to a carrier bandwidth and initial bandwidth part (BWP) bandwidth for the first cell.
The method of claim 1, wherein the channel bandwidth information for the first cell includes one or more downlink channel bandwidth and one or more uplink channel bandwidth for the first cell.
The method of claim 5, wherein the one or more downlink channel bandwidth is indicated per subcarrier spacing (SCS) , and the one or more uplink channel bandwidth is indicated per SCS.
The method of claim 1, further comprising:

receiving the channel bandwidth information for a second cell;

determining that the UE channel bandwidth corresponds to a matching channel bandwidth for the second cell; and

including the second cell in the cell selection or the cell reselection.
An apparatus for wireless communication at a user equipment (UE) , comprising:

means for receiving channel bandwidth information for a first cell;

means for determining, based on the channel bandwidth information, that a UE channel bandwidth is different than a channel bandwidth for the first cell; and

means for excluding the first cell from cell selection or cell reselection for at least a period of time.
The apparatus of claim 8, further comprising means to perform the method of any of claims 2-7.
An apparatus for wireless communication at a user equipment (UE) , comprising:

a memory; and

at least one processor coupled to the memory and configured to perform the method of any of claims 1-7.
A computer-readable medium storing computer executable code for wireless communication at a user equipment (UE) , the code when executed by a processor cause the processor to perform the method of any of claims 1-7.
A method of wireless communication at a base station, comprising:

determining one or more channel bandwidths supported by a cell; and

broadcasting channel bandwidth information for the cell.
The method of claim 12, wherein the base station broadcasts the channel bandwidth information for the cell in system information.
The method of claim 13, wherein the base station broadcasts the channel bandwidth information for the cell in a system information block (SIB) .
The method of claim 12, wherein the base station broadcasts the channel bandwidth information for the cell in addition to a carrier bandwidth and initial bandwidth part (BWP) bandwidth for the cell.
The method of claim 12, wherein the channel bandwidth information for the cell includes one or more downlink channel bandwidth and one or more uplink channel bandwidth for the cell.
The method of claim 16, wherein the one or more downlink channel bandwidth is indicated per subcarrier spacing (SCS) , and the one or more uplink channel bandwidth is indicated per SCS.
An apparatus for wireless communication at a base station, comprising:

means for determining one or more channel bandwidths supported by a cell; and

means for broadcasting channel bandwidth information for the cell.
The apparatus of claim 18, further comprising means to perform the method of any of claims 13-17.
An apparatus for wireless communication at a base station, comprising:

a memory; and

at least one processor coupled to the memory and configured to perform the method of any of claims 12-17.
A computer-readable medium storing computer executable code for wireless communication at a base station, the code when executed by a processor cause the processor to perform the method of any of claims 12-17.
A method of wireless communication at a user equipment (UE) , comprising:

receiving channel bandwidth information for one or more channel bandwidths supported by at least a first cell;

comparing the channel bandwidth information to channel bandwidth of the UE to determine whether the channel bandwidth of the UE matches one or more of the channel bandwidths supported by the first cell; and

determining whether to include or exclude the first cell from cell selection or cell reselection for at least a period of time based on the comparison.
The method of claim 22, wherein the UE determines whether to include or exclude the first cell from the cell selection or the cell reselection based on the comparison that the channel bandwidth of the UE is different than the one or more channel bandwidths supported by the first cell.
The method of claim 23, further comprising:

excluding the first cell from the cell selection or the cell reselection if the channel bandwidth of the UE is different than the one or more channel bandwidths supported by the first cell.
The method of claim 22, further comprising:

including the first cell from the cell selection or the cell reselection if the channel bandwidth of the UE matches at least one channel bandwidth supported by the first cell.
The method of claim 22, further comprising:

determining that the UE channel bandwidth corresponds to a matching channel bandwidth for the second cell; and

including the second cell in the cell selection or the cell reselection.
An apparatus for wireless communication at a user equipment (UE) , comprising:

means for receiving channel bandwidth information for one or more channel bandwidths supported by at least a first cell;

means for comparing the channel bandwidth information to channel bandwidth of the UE to determine whether the channel bandwidth of the UE matches one or more of the channel bandwidths supported by the first cell; and

means for determining whether to include or exclude the first cell from cell selection or cell reselection for at least a period of time based on the comparison.
The apparatus of claim 27, further comprising means to perform the method of any of claims 23-26.
An apparatus for wireless communication at a user equipment (UE) , comprising:

a memory; and

at least one processor coupled to the memory and configured to perform the method of any of claims 22-26.
A computer-readable medium storing computer executable code for wireless communication at a user equipment (UE) , the code when executed by a processor cause the processor to perform the method of any of claims 22-26.