WO2022056711A1

WO2022056711A1 - Method and apparatus with improved cell selection

Info

Publication number: WO2022056711A1
Application number: PCT/CN2020/115544
Authority: WO
Inventors: Ruiqi QIAN; Haojun WANG; Kaikai YANG; Shouqiao ZHU; Jie Ren
Original assignee: Qualcomm Incorporated
Priority date: 2020-09-16
Filing date: 2020-09-16
Publication date: 2022-03-24

Abstract

A user equipment (UE) communicates with a first radio access technology (RAT) cell based on a first RAT and determines a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT. The UE measures one or more cell of the second RAT based on the determined mode and reports the second RAT cell that meets criteria of the determined mode.

Description

METHOD AND APPARATUS WITH IMPROVED CELL SELECTION

BACKGROUND

Technical Field

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

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 communicates with a first radio access technology (RAT) cell based on a first RAT; determines a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT. The apparatus measures one or more cell of the second RAT based on the determined mode and reports the second RAT cell that meets criteria of the determined mode.

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.

FIG. 4 illustrates an example of a UE having a connection to a first node of a first RAT and a second node of a second RAT.

FIG. 5 illustrates an example flowchart including determining a measurement and reporting mode among multiple measurement and reporting modes.

FIG. 6A and 6B illustrate example aspects of measurement and reporting modes.

FIG. 7 illustrates example aspects of a measurement and reporting mode.

FIG. 8 illustrates example aspects of a measurement and reporting mode.

FIG. 9 is a flowchart of a method of wireless communication.

FIG. 10 is a diagram illustrating an example of a hardware implementation for an example apparatus.

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.

In a non-standalone network, a UE may connect to a cell of a first RAT as a primary node or primary cell and may connect to a cell of a second RAT as a secondary node or a secondary cell via the cell of the first RAT. As one non-limiting example, a UE may first connect to an LTE network and then may connect to an NR network as a secondary cell with communication through a core LTE network. Although examples are described herein for LTE and NR, the aspects may be applied to a first RAT and a second RAT that are different than LTE and NR.

In order to detect the NR cell, the UE may perform measurements, e.g., of signal quality from one or more potential NR cells.

If the network configures multiple inter-frequency measurements for secondary node addition, the UE may measure the multiple inter-frequency measurements one-by-one with a single inter-frequency measurement during a measurement gap. The UE may measure the multiple inter-frequency measurements one-by-one in a particular order, e.g., in an ascending order of a measurement ID (e.g., a “measId” ) . If an RSRP measurement for a particular measurement object exceeds the measurement threshold, the UE may report the NR measurement object to the primary cell, e.g., the LTE cell. The UE may be more likely to report an NR measurement object that has an earlier measurement in the one-by-one order, whereas an NR measurement object that has a larger measurement ID may have a better cell quality. Thus, cells with smaller measurement ID are more likely to be added as secondary node yet may not be the cell with the best RSRP.

If the network configures a cell with a smaller measurement ID that has a worse signal quality as the secondary node for the UE 404 instead of a cell with better signal, the user may receive reduced service leading to a less favorable user experience. Aspects presented herein provide a flexible measurement report strategy that may help the UE to add a more optimal NR cell as a secondary node. In order to balance the speed of a measurement report with the optimal selection of an NR cell among different NR measurement objects based on the unique situation of a particular UE, the present application provides several modes of measurement reporting strategy. The UE may flexibly select a strategy or measurement reporting mode based on a usage scenario, operator configuration, etc.

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network 100. 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.

Referring again to FIG. 1, in certain aspects, the UE 104 may communication communicate with a first cell based on a first RAT. For example, the UE 104 may have a connection with base station 102. The UE may be configured to perform and report measurement for cells of a different RAT. For example, the UE may report the measurements for the addition of a secondary node for the UE, for handover purposes, etc. The UE 104 may include a measurement mode component 198 that is configured to determine a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT. The UE 104 may measure one or more cell of the second RAT based on the determined mode and may report the second RAT cell (e.g., for base station 180) that meets criteria of the determined mode. The first cell, e.g., of base station 102, may use the reported measurement to determine whether to indicate to the UE to connect to the base station 180 as a secondary node, in some examples.

Although aspects of the description may be focused on 5G NR and LTE, the concepts described herein may also be applicable to different RATs, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

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 measurement mode component 198 of FIG. 1.

In a non-standalone network, a UE may connect to a cell of a first RAT as a primary node or primary cell and may connect to a cell of a second RAT as a secondary node or a secondary cell via the cell of the first RAT. As one non-limiting example, a UE may first connect to an LTE network and then may connect to an NR network as a secondary cell with communication through a core LTE network. FIG. 4 illustrates an example of a UE 404 having dual connectivity with multiple RATs (e.g., an LTE RAT and an NR RAT) . A first RAT may operate as a primary node (MN) and a second RAT may operate as a secondary node (SN) . One example of this multiple RAT communication is Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (E-UTRA) New Radio –Dual Connectivity (EN-DC) . Although examples are provided for EN-DC with LTE and NR to illustrate the concepts, the concepts are applicable to other RATs and other dual connectivity scenarios, as well. Another example is multi-RAT dual connectivity (MR-DC) .

Although examples are described herein for LTE and NR, the aspects may be applied to a first RAT and a second RAT that are different than LTE and NR.

In an EN-DC configuration, the UE 404 may be connected to an LTE network and then may connect to an NR network via an RRC connection reconfiguration process. The UE 404 communicates with both an LTE node 402 and an NR node 480, e.g., as illustrated in the EN-DC example 400 in FIG. 4. As illustrated in FIG. 4, the LTE node 402 may have a control plane connection with the LTE core network and may have a control plane connection, e.g., an X2 connection, with the NR node. For the user plane, or data plane, the LTE node may have a user plane connection with the LTE network and the NR network, and the NR node 480 may have a user plane connection with the NR network.

In order to detect the NR cell, the UE may perform measurements, e.g., of signal quality from one or more potential NR cells. A trigger event may trigger the UE to report the measurement of a cell to the LTE network. For example, a B1 trigger event may be based on an inter-RAT neighbor cell measurement becoming greater than a threshold. For example, if an NR cell measurement meets a threshold, the UE may report the NR cell to the LTE network. The LTE network may use the NR cell measurement to determine whether to indicate for the UE to connect to the NR cell as a secondary cell. The NR cell measurements may be based on a reference signal of the NR cell, e.g., a reference signal received power (RSRP) , which the UE may report to the LTE network.

The UE 404 may perform the NR cell measurements during a period when no transmission/reception is scheduled to occur for the LTE cell. The period or duration may be referred to as a measurement gap. The measurement gap enables the UE to switch away from transmission/reception with the LTE cell to perform the signal quality measurement on an NR cell. The UE 404 may then return to reception/transmission with the LTE cell. The NR measurements may be performed on a different frequency than the LTE communication, an may be referred to as inter-frequency measurements. Thus, the UE 404 may switch away from transmission/reception on a first frequency in order to perform measurements on a different frequency during the measurement gap. The LTE cell may configure or provide the measurement gap for the UE 404, e.g., configuring one or more parameters for a measurement gap such as the presence of a gap, a gap length, a number of gaps, a gap pattern, etc.

A UE 404 may measure a limited number of absolute radio-frequency channel number (ARFCN) in each measurement gap. If the network configures multiple inter-frequency measurements for secondary node addition, the UE 404 may measure the multiple inter-frequency measurements one-by-one with a single inter-frequency measurement during a measurement gap. The UE 404 may measure the multiple inter-frequency measurements one-by-one in a particular order. The order may be based on an ascending order of a measurement ID (e.g., a “measId” ) . Each configured inter-frequency measurement for a cell may be referred to as a measurement object. A configured measurement for an NR cell may be referred to as an NR measurement object (e.g., which may be referred to as a “measObjectNR” ) . Each configured measurement object may be associated with a measurement ID. If an RSRP measurement for a particular measurement object exceeds the measurement threshold, the UE 404 may determine that a B1 event has occurred and may report the NR measurement object to the primary cell, e.g., the LTE cell. The UE 404 may be more likely to report an NR measurement object that has an earlier measurement in the one-by-one order, whereas an NR measurement object that has a larger measurement ID may have a better cell quality. Thus, cells with smaller measurement ID are more likely to be added as secondary node yet may not be the cell with the best RSRP.

If the network configures a cell with a smaller measurement ID that has a worse signal quality as the secondary node for the UE 404 instead of a cell with better signal, the user may receive reduced service leading to a less favorable user experience.

Aspects presented herein provide a flexible B1 measurement report strategy that may help the UE 404 to add a more optimal NR cell as a secondary node. In order to balance the speed of a measurement report with the optimal selection of an NR cell among different NR measurement objects based on the unique situation of a particular UE, the present application provides several modes of measurement reporting strategy. The UE 404 may flexibly select a strategy or measurement reporting mode based on a usage scenario, operator configuration, etc.

In a first mode (which may be referred to herein as “Mode 1” ) , the UE 404 may select a best cell from among multiple cells before reporting the cell to the network. For example, the UE 404 may apply the first mode if the UE is stationary or moving at a lower speed (e.g., at a speed below speed threshold) . In the first mode, the UE 404 may complete the measurement of all measurement objects. The UE 404 may determine each of the measurement objects with an RSRP measurement that meets the criteria of a B1 event and may compare the measurement results of the measurement objects. The UE 404 may then report the cell with the best signal quality among all the cells having a signal quality measurement that meets the B1 threshold. Thus, the UE 404 may wait to report a measurement object that has a signal quality that meets the B1 threshold. The UE 404 may wait until measurement of each configured measurement object in order to compare each of the measurement objects that meet the B1 criteria. If the UE is moving at a higher speed, the UE 404 may select a different mode, which may be referred to as a fast reporting mode.

In a second mode (which may be referred to herein as “Mode 2” or a fast reporting mode) , the UE 404 may measure all measurement objects in sequence of ascending order of the measurement ID and may report a measurement ID as soon as a measurement reaches the B1 threshold, e.g., without waiting to compare the measurement to other measurement objects.

In a third mode (which may be referred to herein as “Mode 3” ) , which may be referred to as a bandwidth priority mode, the UE may prioritize measurement and/or reporting of a particular frequency. For example, the UE 404 may prioritize measurement objects having a mmW frequency over measurement objects having a different frequency. In order examples, the UE 404 may prioritize measurement objects having a larger bandwidth over measurement objects having a smaller bandwidth. The UE 404 may classify the configured measurement objects into higher priority measurement objects and lower priority measurement objects. The classification may be based on a priority set by the UE in some examples. The UE 404 may then prioritize measurements and reports for the higher priority frequencies or higher priority measurement objects.

In a first example based on the third mode (which may be referred to herein as “Mode 3.1” ) , the UE 404 may complete the measurements for all configured measurement objects and determine which measurement objects meet the B1 event criteria. Then, the UE 404 may determine a cell from among the higher priority cells that meet the B1 event criteria, e.g., RSRP threshold, and may report the cell having the best signal quality measurement.

In a second example based on the third mode (which may be referred to herein as “Mode 3.2” ) , the UE 404 may prioritize measurement of the higher priority measurement objects (e.g., performing the measurement of the higher priority measurement objects before the lower priority measurement objects) . If a cell measurement meets the B1 event criteria, e.g., RSRP threshold, the UE 404 may report the cell without waiting to compare the measurements for other measurement objects.

The UE 404 may select between the various measurement and reporting modes based on a speed of the UE and/or based on whether a priority is indicated for the measurement objects (e.g., a frequency priority being configured) .

FIG. 5 illustrates an example flowchart for a method of cell measurement and reporting based on different measurement and reporting modes. When the UE receives a measurement configuration from a network, such as an NR measurement configuration from an LTE network, the UE may determine a group of measurement IDs that have a same B1 event, e.g., a same B1 threshold, and different NR measurement objects. In some examples, the measurement objects may be for adding an NR cell as a secondary node to the LTE. In some examples, the measurement objects may be for an LTE to NR handover.

As illustrated at step 502, the UE may determine whether a priority level is configured or indicated for a frequency and/or bandwidth to be measured. For example, the UE may read a configuration of a configuration file and may select a measurement and reporting strategy based on whether there is priority information in the configuration file, in some examples.

If a priority is not configured, the UE may proceed to determine whether the speed of the UE meets a threshold, at 504, that indicates that the UE is in a high speed mode. If the UE is not in a high speed mode, the UE may perform measurement and reporting of NR cells based on Mode 2. FIG. 6A illustrates Mode 2. At 602, the UE measures a reference signal quality (e.g., RSRP) for each NR measurement object during measurement gaps for the LTE cell in an order based on the measurement object ID (“measID” ) , e.g., in ascending order of IDs. At 604, determines that there is a cell in one NR measurement object that reaches the B1 threshold. In response to the determination at 604, the UE reports the measurement for the NR cell, at 606, e.g., without waiting to perform additional measurements for other measurement objects.

If the UE is not in a high speed mode, the UE may perform measurement and reporting of NR cells based on Mode 1 in which the UE measures multiple measurement objects and reports a cell having a better measured signal quality in order to report a cell having a higher signal quality from among the measurement objects. FIG. 7 illustrates example aspects of Mode 1. As illustrated at 702, the UE may sequentially measure the configured NR measurement objects in an order during the measurement gaps for the LTE cell. The order may be based on the measurement object ID (e.g., measID) , such as in an ascending order of IDs. At 704, the UE may determine that an NR measurement object meets the B1 signal quality threshold. At 706, the UE may determine whether the measurement ID of the measurement object is the largest for the B1 event. If so, the UE reports the measurement to the LTE cell, at 708. If the measurement object is not the largest for the measurement object in the particular B1 event, the UE may determine, at 712, whether there are cells in another NR measurement object that reach the B1 threshold. If there is a cell in another NR measurement object that reaches the B1 threshold, the UE reports the NR cell to the LTE cell, at 714. If there is no cell in another NR measurement object that reaches the B1 threshold, the UE may compare the signal quality of the cells, at 716, and may report a measurement for the cell (e.g., ARFCN) having a better signal quality. At 718, the UE continues to report other measurements reports for cells that reach the B1 threshold. The UE may apply an interval gap period when measuring and/or reporting other cells.

In some examples, prior to the determination, at 712, the UE may wait for a gap period, at 710. The gap period may be, e.g., 2-4 seconds. In some examples, the gap period, at 710, may be a fixed value. In other examples, the gap period, at 710, may vary based on a measurement ID. As an example, a time period may be determined where T=N _offset *T _{gap_period}, where N _offset is a biggest measurement ID in a B1 event minus a current measurement ID. The gap period for the UE to apply at 710, may be determined as T _wait = mine (T _max, T) , where T _max = 3s –an amount of measuring time currently used. The total measurement time may be limited to a certain amount of time, such as 3 seconds. For example, the network may delete the measurement object after the limited amount of time, e.g., 3 seconds.

At 504, if a priority is configured for a frequency, the UE proceeds to determine the measurement and reporting mode based on a speed of the UE, at 506. For example, determine whether the speed of the UE meets a threshold, at 506, that indicates that the UE is in a high speed mode. If the UE is in a high speed mode, the UE may perform measurement and reporting of NR cells based on Mode 3.2. FIG. 6B illustrates an example of Mode 3.2. At 608, the UE determines the ARFCN priority configuration, e.g., in a configuration file. At 610, the UE sequentially measures the configured NR measurement objects at each measurement gap. The UE first measures the higher priority ARFCN and then may follow an order based on measurement ID. At 612, the UE determines that an NR measurement object reaches the B1 threshold. The UE reports the measurement for the NR measurement object to the LTE cell, at 614, e.g., without waiting to perform additional measurements for comparison.

If the UE is not in a high speed mode, the UE may perform measurement and reporting of NR cells based on Mode 3.1. FIG. 8 illustrates an example of Mode 3.1. At 802, the UE measures the NR measurement objects sequentially at each measurement gap for the LTE cell. The UE may first measure the higher priority ARFCN, and then may follow an order based on measurement ID. At 804, the UE determines that a cell in one NR measurement object reaches the B1 threshold. At 806, the UE determines whether the NR measurement object is a higher priority measurement object. If the NR measurement object is not a higher priority measurement object, the UE may wait for a gap period, at 808. The gap period may be similar to the gap period 710 in FIG. 7. At 810, the UE determines whether there are cells in other NR measurement objects that reach the B1 threshold. If not, the UE reports the measurement report for the cell reaching the B1 threshold, at 816. If there is another cell in another NR measurement object that reaches the B1 threshold, the UE compares the signal quality of the cells, at 812. The UE reports the measurement report of the cell (e.g., ARFCN) having a better signal quality among the cell determined at 804 and the additional cell determined at 810. At 814, the UE may continue to report other measurement reports for other NR cells that reach the B1 threshold. The UE may apply an interval gap period between such measurement reports, in some examples.

If the UE determines, at 806, that the NR measurement object has a high priority, the UE may proceed to 820. As illustrated at 818, the UE may apply a gap period, such as described in connection with 710 in FIG. 7. At 820, the UE determines whether there are cells in other high priority NR measurement objects that reach the B1 threshold. If there are no other cells in other high priority NR measurement objects that reach the B1 threshold, the UE reports, at 816, the measurement report for the cell that was determined to reach the B1 threshold at 806, e.g., without waiting for another measurement for comparison. If there are other cells in other high priority NR measurement objects that reach the B1 threshold, the UE compares the signal quality of the cells meeting the B1 threshold, at 822. The UE reports the measurement report for a cell (e.g., ARFCN) having a better quality among the cells of the high priority NR measurement objects that meet the B1 threshold. At 824, the UE may continue to report other measurement reports for other NR cells that reach the B1 threshold. The UE may apply an interval gap period between such measurement reports, in some examples.

FIG. 9 is a flowchart 900 of a method of wireless communication. The method may be performed by a UE (e.g., the

UE

104, 350, 404; the apparatus 1002) . Optional aspects are illustrated with a dashed line. The method may enable the UE to balance quick reporting of NR cell measurements with higher quality NR cell measurements by selecting between different measurement and reporting modes.

At 902, the UE communicates with a first radio access technology (RAT) cell based on a first RAT. For example, the UE may have an established connection with an LTE cell. The first cell may configure the UE to perform measurements, based on measurement objects of the second RAT, e.g., NR measurement objects. The measurements may be for the addition of an NR cell as a secondary node for the UE, for an LTE to NR handover for the UE, etc. The communication may be performed, e.g., by the first RAT component 1040 of the communication manager 1032 of the apparatus 1002.

At 904, the UE determines a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT. For example, the UE may determine between any combination of the modes described herein, e.g., between any of Mode 1, Mode 2, Mode 3, Mode 3.1, or Mode 3.2. Example aspects of determining between measurement and report modes is described in connection with FIG. 5. For Example, the UE may determine the mode from the plurality of modes based on at least one of a speed of the UE, e.g., at 504 or 506, or frequency priority information, e.g., at 502. The determination may be performed, e.g., by the mode determination component 1042 of the communication manager 1032 of the apparatus 1002.

At 906, the UE measures one or more cell of the second RAT based on the determined mode. For example, the UE may measure a cell quality based on a reference signal of the cell, e.g., an RSRP for the cell. The UE may be configured to measure multiple measurement objects and may perform measurements for one of the measurement objects in each measurement gap provided by the first cell. The measurement may be performed, e.g., by the second RAT measurement component 1044 of the communication manager 1032 of the apparatus 1002.

At 910, the UE reports the second RAT cell that meets criteria of the determined mode. The criteria may be based, at least in part, on the measurement of the cell meeting a B1 threshold. The criteria may be based on additional factors depending on the mode selected for the measurement and reporting. The report may be performed, e.g., by the report component 1046 of the communication manager 1032 of the apparatus 1002.

The UE may preferentially measure or report higher priority measurement objects of the second RAT, e.g., as in Mode 3, if the frequency priority information is configured for the UE.

For example, if the frequency priority information is configured for the UE, the UE may measure each of a set of measurement objects of the second RAT, e.g., according to mode 3.1, The UE may further determine one or more cells having a higher priority and having the measurement meeting a threshold. The UE may then report the second RAT cell having a highest measurement among the one or more cells having the higher priority.

If the frequency priority information is configured for the UE and a speed of the UE is above a speed threshold, the UE may preferentially measure the higher priority measurement objects of the second RAT, e.g., according to mode 3.2. The UE may then report the second RAT cell with a first measurement that meets a measurement threshold.

If the frequency priority information is not configured for the UE and a speed of the UE is below a speed threshold, the UE may measure each measurement object of the second RAT, e.g., according to Mode 2. The UE may report the second RAT cell having a highest signal quality.

If the frequency priority information is not configured for the UE and a speed of the UE is above a speed threshold, the UE may measure one or more measurement object of the second RAT in ascending order of a measurement object identifier, e.g., according to Mode 2. The UE may report the second RAT cell having a first measurement to meet a measurement threshold.

In some examples, at 908, the UE applies a time gap after measuring a measurement object of the second RAT that meets a measurement threshold and before reporting the second RAT cell. The time gap may correspond to the time gap described in connection with any of 710, 808, or 818, for example. The time gap may be a fixed value. The time gap may be based on a measurement ID of the measurement object that meets the measurement threshold. The UE may continue measuring one or more additional measurement objects of the second RAT during the time gap. The application of the time gap may be performed, e.g., by the time gap component 1048 of the communication manager 1032 of the apparatus 1002.

FIG. 10 is a diagram 1000 illustrating an example of a hardware implementation for an apparatus 1002. The apparatus 1002 is a UE and includes a cellular baseband processor 1004 (also referred to as a modem) coupled to a cellular RF transceiver 1022 and one or more subscriber identity modules (SIM) cards 1020, an application processor 1006 coupled to a secure digital (SD) card 1008 and a screen 1010, a Bluetooth module 1012, a wireless local area network (WLAN) module 1014, a Global Positioning System (GPS) module 1016, and a power supply 1018. The cellular baseband processor 1004 communicates through the cellular RF transceiver 1022 with the UE 104 and/or BS 102/180. The cellular baseband processor 1004 may include a computer-readable medium /memory. The computer-readable medium /memory may be non-transitory. The cellular baseband processor 1004 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 1004, causes the cellular baseband processor 1004 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 1004 when executing software. The cellular baseband processor 1004 further includes a reception component 1030, a communication manager 1032, and a transmission component 1034. The communication manager 1032 includes the one or more illustrated components. The components within the communication manager 1032 may be stored in the computer-readable medium /memory and/or configured as hardware within the cellular baseband processor 1004. The cellular baseband processor 1004 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 1002 may be a modem chip and include just the baseband processor 1004, and in another configuration, the apparatus 1002 may be the entire UE (e.g., see 350 of FIG. 3) and include the additional modules of the apparatus 1002.

The communication manager 1032 may include a first RAT component 1040 configured to communicate with a first radio access technology (RAT) cell based on a first RAT, e.g., as described in connection with 902. The communication manager 1032 may include a mode determination component 1042 configured to determine a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT, e.g., as described in connection with 904. The communication manager 1032 may include a second RAT measurement component 1044 configured to measure one or more cell of the second RAT based on the determined mode, e.g., as described in connection with 906. The communication manager 1032 may include a report component 1046 configured to the second RAT cell that meets criteria of the determined mode, e.g., as described in connection with 910. The communication manager 1032 may include a time gap component 1048 configured to apply a time gap after measuring a measurement object of the second RAT that meets a measurement threshold and before reporting the second RAT cell, e.g., as described in connection with 908.

The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowcharts of FIGs. 5-9. As such, each block in the aforementioned flowcharts of FIGs. 5-9 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 1002, and in particular the cellular baseband processor 1004, includes means for means for communicating with a first radio access technology (RAT) cell based on a first RAT. The apparatus may include means for determining a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT. The apparatus may include means for measuring one or more cell of the second RAT based on the determined mode and means for reporting the second RAT cell that meets criteria of the determined mode. The apparatus may further include means for applying a time gap after measuring a measurement object of the second RAT that meets a measurement threshold and before reporting the second RAT cell. The aforementioned means may be one or more of the aforementioned components of the apparatus 1002 configured to perform the functions recited by the aforementioned means. As described supra, the apparatus 1002 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.

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: communicating with a first RAT cell based on a first RAT; determining a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT; measuring one or more cell of the second RAT based on the determined mode; and reporting the second RAT cell that meets criteria of the determined mode.

In Example 2, the method of Example 1 further includes that the first RAT is based on LTE and the second RAT is based on NR.

In Example 3, the method of Example 1 or Example 2 further includes that the UE determines the mode from the plurality of modes based on at least one of a speed of the UE or frequency priority information.

In Example 4, the method of any of Examples 1-3 further includes that the UE preferentially measures or reports higher priority measurement objects of the second RAT if the frequency priority information is configured for the UE.

In Example 5, the method of any of Examples 1-4 further includes that, if the frequency priority information is configured for the UE, the UE measures each of a set of measurement objects of the second RAT, the method further comprising: determining one or more cells having a higher priority and having the measurement meeting a threshold, wherein the UE reports the second RAT cell having a highest measurement among the one or more cells having the higher priority.

In Example 6, the method of any of Examples 1-5 further includes that, if the frequency priority information is configured for the UE and a speed of the UE is above a speed threshold, the UE preferentially measures the higher priority measurement objects of the second RAT and reports the second RAT cell with a first measurement that meets a measurement threshold.

In Example 7, the method of any of Examples 1-6 further includes that, if the frequency priority information is not configured for the UE and a speed of the UE is below a speed threshold, the UE measures each measurement object of the second RAT and reports the second RAT cell having a highest signal quality.

In Example 8, the method of any of Examples 1-7 further includes that, if the frequency priority information is not configured for the UE and a speed of the UE is above a speed threshold, the UE measures one or more measurement object of the second RAT in ascending order of a measurement object identifier and reports the second RAT cell having a first measurement to meet a measurement threshold.

In Example 9, the method of any of Examples 1-8 further includes applying a time gap after measuring a measurement object of the second RAT that meets a measurement threshold and before reporting the second RAT cell.

In Example 10, the method of any of Examples 1-9 further includes that the time gap is a fixed value.

In Example 11, the method of any of Examples 1-10 further includes that the time gap is based on a measurement ID of the measurement object that meets the measurement threshold.

In Example 12, the method of any of Examples 1-11 further includes that the UE continues measuring one or more additional measurement objects of the second RAT during the time gap.

Example 13 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 1-12.

Example 14 is a system or apparatus including means for implementing a method or realizing an apparatus as in any of Examples 1-12.

Example 15 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 1-12.

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:

communicating with a first radio access technology (RAT) cell based on a first RAT;

determining a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT;

measuring one or more cell of the second RAT based on the determined mode; and

reporting the second RAT cell that meets criteria of the determined mode.
The method of claim 1, wherein the first RAT is based on long term evolution (LTE) and the second RAT is based on new radio (NR) .
The method of claim 1, wherein the UE determines the mode from the plurality of modes based on at least one of a speed of the UE or frequency priority information.
The method of claim 3, wherein the UE preferentially measures or reports higher priority measurement objects of the second RAT if the frequency priority information is configured for the UE.
The method of claim 4, wherein if the frequency priority information is configured for the UE, the UE measures each of a set of measurement objects of the second RAT, the method further comprising:

determining one or more cells having a higher priority and having the measurement meeting a threshold, wherein the UE reports the second RAT cell having a highest measurement among the one or more cells having the higher priority.
The method of claim 4, wherein if the frequency priority information is configured for the UE and the speed of the UE is above a speed threshold, the UE preferentially measures the higher priority measurement objects of the second RAT and reports the second RAT cell with a first measurement that meets a measurement threshold.
The method of claim 3, wherein if the frequency priority information is not configured for the UE and the speed of the UE is below a speed threshold, the UE measures each measurement object of the second RAT and reports the second RAT cell having a highest signal quality.
The method of claim 3, wherein if the frequency priority information is not configured for the UE and the speed of the UE is above a speed threshold, the UE measures one or more measurement object of the second RAT in ascending order of a measurement object identifier and reports the second RAT cell having a first measurement to meet a measurement threshold.
The method of claim 1, further comprising:

applying a time gap after measuring a measurement object of the second RAT that meets a measurement threshold and before reporting the second RAT cell.
The method of claim 9, wherein the time gap is a fixed value.
The method of claim 9, wherein the time gap is based on a measurement identifier (ID) of the measurement object that meets the measurement threshold.
The method of claim 9, wherein the UE continues measuring one or more additional measurement objects of the second RAT during the time gap.
An apparatus for wireless communication at a user equipment (UE) , comprising:

means for communicating with a first radio access technology (RAT) cell based on a first RAT;

means for determining a mode from a plurality of modes for reporting measurement of a second RAT cell based on a second RAT;

means for measuring one or more cell of the second RAT based on the determined mode; and

means for reporting the second RAT cell that meets criteria of the determined mode.
The apparatus of claim 13, further comprising means to perform the method of any of claims 2-12.
An apparatus for wireless communication at a user equipment (UE) , comprising:

memory; and

at least one processor coupled to the memory and configured to perform the method of any of claims 2-12.
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 2-12.