WO2021232356A1

WO2021232356A1 - Techniques for inducing handover to 5g anchor cells

Info

Publication number: WO2021232356A1
Application number: PCT/CN2020/091576
Authority: WO
Inventors: Yuankun ZHU; Chaofeng HUI; Fojian ZHANG; Pan JIANG; Hao Zhang; Yi Liu; Jian Li; Shouxin XU; Bo Yu
Original assignee: Qualcomm Incorporated
Priority date: 2020-05-21
Filing date: 2020-05-21
Publication date: 2021-11-25

Abstract

A user equipment (UE) may be configured to induce a handover to a 5G anchor cell in a non-stand-alone network deployment. The UE may determine that a frequency of at least one anchor neighbor cell on a neighbor cell list corresponds to a frequency band supporting a 5G non-stand-alone network. The UE may measure a signal strength of the at least one anchor neighbor cell. The UE may determine that the signal strength of an anchor neighbor cell satisfies a minimum threshold and add a compensation value to the signal strength to determine a compensated signal strength in response to the determination. The UE may determine that the anchor neighbor cell satisfies an event reporting condition based on the compensated signal strength and transmit a measurement report. The UE may receive a handover command for a handover to the anchor neighbor cell in response to the measurement report.

Description

TECHNIQUES FOR INDUCING HANDOVER TO 5G ANCHOR CELLS

BACKGROUND

Technical Field

The present disclosure relates generally to wireless communication systems, and more particularly, to techniques for inducing handover to 5G anchor cells.

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, the disclosure provides a method of wireless communication for a user equipment (UE) . The method may include receiving, from a serving cell, a neighbor cell list indicating a plurality of neighbor cells. The method may include determining that a frequency of at least one anchor neighbor cell on the neighbor cell list corresponds to a frequency band supporting a 5G non-stand-alone network. The method may include measuring a signal strength of the at least one anchor neighbor cell. The method may include determining that the signal strength of an anchor neighbor cell satisfies a minimum threshold adding a compensation value to the signal strength of the anchor neighbor cell to determine a compensated signal strength in response to the determination that the signal strength of the anchor neighbor cell satisfies the minimum threshold. The method may include determining that the anchor neighbor cell satisfies an event reporting condition based on the compensated signal strength. The method may include transmitting a measurement report to the serving cell in response to the determination that the anchor neighbor cell satisfies the event reporting condition. The method may include receiving a handover command from the serving cell for a handover to the anchor neighbor cell in response to the measurement report.

In some implementations, determining that the frequency of the at least one anchor neighbor cell in the neighbor cell list corresponds to the frequency band supporting the 5G non-stand-alone network includes determining the frequency band supporting the 5G non-stand-alone network based on a network operator.

In some implementations, the minimum threshold is between -110 dBm and -100 dBm.

In some implementations, the compensation value is between 2 dB and 20 dB.

In some implementations, the event reporting condition is satisfied when the compensated signal strength of the anchor neighbor cell is better than a signal strength of the serving cell by an offset. The signal strength of the anchor neighbor cell without the compensation value may be less than the signal strength of the serving cell.

In some implementations, the event reporting condition is satisfied when the compensated signal strength of the anchor neighbor cell is better than an event threshold.

In some implementations, the signal strength is a reference signal received power (RSRP) .

The disclosure also provides an apparatus (e.g., a UE) including a memory storing computer-executable instructions and at least one processor configured to execute the computer-executable instructions to perform the above method, an apparatus including means for performing the above method, and a non-transitory computer-readable medium storing computer-executable instructions for performing the above method.

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 5G/NR frame.

FIG. 2B is a diagram illustrating an example of DL channels within a 5G/NR subframe. FIG. 2C is a diagram illustrating an example of a second 5G/NR frame.

FIG. 2D is a diagram illustrating an example of a 5G/NR subframe.

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

FIG. 4 is a diagram illustrating example communications and components of base stations and a UE.

FIG. 5 is a flow diagram illustrating an example method of inducing a handover to a 5G anchor cell.

FIG. 6 is a conceptual data flow diagram illustrating the data flow between different means/components in an example UE.

FIG. 7 is flowchart of an example of a method of wireless communication for a UE.

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.

A network deployment for a network operator may include cells for a most recent radio access technology (RAT) as well as legacy cells operating according to a different RAT. For example, a deployment for a non-stand-alone 5G new radio (5G NR) system may include 4G LTE cells as well as legacy cells for 3G and 2G. Some of the LTE cells serve as 5G anchor cells that provide 5G access, while other LTE cells do not provide 5G access. Dual connectivity may refer to a capability of a device to establish two or more concurrent connections using different RAT types. For example, a UE may connect to both an LTE network (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (E-UTRA) ) and a 5G NR network. An example network deployment referred to as E-UTRA-NR Dual Connectivity (EN-DC) may include both LTE base station (s) (also referred to as eNB) and 5G NR base station (s) (also referred to as gNB) and an LTE core network referred to as an evolved packet core (EPC) . An EN-DC network deployment may make use of existing LTE infrastructure for rapid deployment of 5G NR access network technology. Additionally, in some non-stand-alone 5G NR deployments such as EN-DC, some 4G LTE cells may serve as anchor cells for 5G NR access. One issue for UEs is that handovers between cells are based on measurements of the cells rather than capability of the cell to provide 5G access. For instance, when a UE is connected to a cell that is not capable of providing 5G access but has a strong signal, the UE may not be handed over to a 5G capable cell even when the UE has a high throughput data request.

In an aspect, the present disclosure provides techniques for inducing a handover to a 5G anchor cell in a non-stand-alone 5G NR deployment. While connected to a non-5G capable serving cell, a UE may be configured with a list of neighbor cells. The UE may determine that a frequency of at least one neighbor cell in the neighbor cell list corresponds to a frequency band supporting a 5G non-stand-alone network. Accordingly, the at least one neighbor cell may be considered a 5G anchor cell. The UE may measure a signal strength of the at least one anchor neighbor cell, and any other neighbor cells. The UE may determine that the signal strength of an anchor neighbor cell satisfies a minimum threshold. The UE may add a compensation value to the signal strength of the anchor neighbor cell to determine a compensated signal strength in response to the determination that anchor neighbor cell satisfies a minimum threshold. The UE may determine that the signal strength of the anchor neighbor cell satisfies an event reporting condition based on the compensated signal strength. The UE may transmit a measurement report in response to the determination that the anchor neighbor cell satisfies the event reporting condition. The UE may receive a handover command for a handover to the anchor neighbor cell in response to the measurement report. Accordingly, the UE may induce a handover to the anchor neighbor cell, which may be able to provide 5G access with greater throughput than other potential serving cells.

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.

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.

In an aspect, as illustrated, one or more of the UEs 104 may include a handover component 140 that enables a UE to induce a handover to a 5G anchor cell is a non-stand-alone deployment. The handover component 140 may include: a configuration component 141 configured to receive a neighbor cell list indicating a plurality of neighbor cells; an anchor band component 142 configured to determine that a frequency of at least one anchor neighbor cell in the neighbor cell list corresponds to a frequency band supporting a 5G non-stand-alone network; a measurement component 143 configured to measure a signal strength of the at least one anchor neighbor cell; a threshold component 144 configured to determine that the signal strength of the anchor neighbor cell satisfies a minimum threshold; a compensation component 145 configured to add a compensation value to the signal strength of the anchor neighbor cell to determine a compensated signal strength in response to the determination; an evaluation component 146 configured to determine that the anchor neighbor cell satisfies an event reporting condition based on the compensated signal strength; and a reporting component 147 configured to transmit a measurement report in response to the determination that the anchor neighbor cell satisfies the event reporting condition. The handover component 140 may be configured receive a handover command for a handover to the anchor neighbor cell in response to the measurement report.

In an aspect, one or more of the base station 102 may include a serving cell component 198. The serving cell component 198 may transmit a configuration message including the neighbor cell list and transmit one or more reference signals to be used for measurements. The serving cell component 198 also may transmit the handover command in response to a measurement report.

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) , which may be wired or wireless. 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, which may be wired or wireless. 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 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, FlashLinQ, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the 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 in a 5 GHz unlicensed frequency spectrum. 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 5 GHz unlicensed frequency spectrum 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.

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 (mmW) frequencies, and/or near mmW frequencies in communication with the UE 104. When the gNB 180 operates in mmW or near mmW frequencies, the gNB 180 may be referred to as an mmW base station. Extremely high frequency (EHF) is part of the RF in the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10 millimeters. Radio waves in the band may be referred to as a millimeter wave. Near mmW may extend down to a frequency of 3 GHz with a wavelength of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, also referred to as centimeter wave. Communications using the mmW /near mmW radio frequency band (e.g., 3 GHz –300 GHz) has extremely high path loss and a short range. The mmW base station 180 may utilize beamforming 182 with the UE 104 to compensate for the extremely high 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 a 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 PS Streaming 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.

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 including future 6G 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 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 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 X is flexible for use between DL/UL, and subframe 3 being configured with slot format 34 (with mostly UL) . While

subframes

3, 4 are shown with slot formats 34, 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 5 allow for 1, 2, 4, 8, 16, and 32 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 5. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=5 has a subcarrier spacing of 480 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.

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 _x for one particular configuration, where 100x is the port number, 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 (PTRS) .

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) , each CCE including nine RE groups (REGs) , each REG including four consecutive REs in an OFDM symbol. 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. 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 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 318TX. Each transmitter 318TX may modulate an RF carrier with a respective spatial stream for transmission.

At the UE 350, each receiver 354RX receives a signal through its respective antenna 352. Each receiver 354RX 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 handover component 140 of FIG. 1.

FIG. 4 is a diagram 400 illustrating example communications and components of base stations 102-a and 102-b and a UE 104. The UE 104 may include the handover component 140. The base station 102-a may be a cell that is not capable of providing 5G access. For example, the base station 102-a may be a non-5G capable LTE cell. The base station 102-b may be an LTE cell that acts as a 5G anchor cell. Each of the base stations 102-a and 102-b may include a serving cell component 198. The serving cell component 198 may transmit a configuration message 410 for a cell of the respective base station 102. The configuration message 410 may include a neighbor cell list 412. The serving cell component 198 also may transmit reference signals 420. The reference signals 420 also may be referred to as pilot signals.

As discussed above regarding FIG. 1, handover component 140 may include the configuration component 141, the anchor band component 142, the measurement component 143, the threshold component 144, the compensation component 145, the evaluation component 146, and the reporting component 147. The handover component 140 may also include a receiver component 470 and a transmitter component 472. The receiver component 470 may include, for example, a radio frequency (RF) receiver for receiving the signals described herein. The transmitter component 472 may include, for example, an RF transmitter for transmitting the signals described herein. In an aspect, the receiver component 470 and the transmitter component 472 may be co-located in a transceiver.

Initially, the UE 104 may be in a connected mode with the base station 102-a as the primary serving cell. For instance, the UE 104 may be configured based on one or more configuration message 410. The UE 104 may monitor reference signals 420, as well as a control channel 422 from the base station 102-a. The UE 104 may be scheduled to transmit or receive on one or more data channels 430 via the base station 102-a. The UE 104 may be capable of 5G access, but the base station 102-a may not be capable of providing 5G access. The handover component 140 may induce a handover to a 5G anchor cell (e.g., base station 102-b) such that the UE 104 is able to obtain 5G access after the handover. For example, the handover component 140 and/or the configuration component 141 may receive the configuration message 410 from the base station 102-a. The handover component 140 and/or the anchor band component 142 may determine the neighbor cell list 412, which may include the frequency of the base station 102-b. The handover component 140 and/or the anchor band component 142 may determine that the frequency of the base station 102-b corresponds to a frequency band supporting a 5G non-stand-alone network. The handover component 140 and/or the measurement component 143 may perform inter-frequency and/or inter-RAT measurements to determine a signal strength of at least the base station 102-b. The handover component 140 and/or the threshold component 144 may determine that the signal strength of the base station 102-b satisfies a minimum threshold. The handover component 140 and/or the compensation component 145 may add a compensation value to the signal strength of the base station 102-b to determine a compensated signal strength in response to the determination that the signal strength of the base station 102-b satisfies the minimum threshold. The handover component 140 and/or the evaluation component 146 may determine whether the base station 102-b satisfies an event reporting condition based on the compensated signal strength. If the base station 102-b satisfies the event reporting condition, the handover component 140 and/or the reporting component 147 may transmit a measurement report 440 including the compensated signal strength. The handover component 140 may receive a handover command 450 for a handover to the base station 102-b in response to the measurement report.

FIG. 5 is a flow diagram illustrating an example method 500 of inducing a handover to a 5G anchor cell. The method 500 may be performed by the UE 104 including the handover component 140.

At block 510, the UE 104 may be in a connected mode with a non-5G cell. For example, the serving cell may be an LTE cell. The UE 104 may determine that the serving cell is not a 5G anchor cell based on the frequency of the serving cell not being in a 5G anchor band. At block 520, the UE 104 may execute LTE neighbor cell measurements to determine a signal strength (e.g., reference signal received power (RSRP) ) of each neighbor cell indicated on the neighbor cell list 412. At block 530, the UE 104 may determine whether the measured cell is a 5G anchor cell based on the frequency of the measured cell. If the measured cell is not a 5G anchor cell, the UE 104 may proceed directly to block 560. If the measured cell is a 5G anchor cell, the UE 104 may proceed to block 540. At block 540, the UE 104 may determine whether the measured RSRP of a 5G anchor cell is greater than a threshold. If the measured RSRP is not greater than the threshold, the UE 104 may proceed directly to block 560. If the measured RSRP is greater than the threshold, the UE 104 may proceed to block 550. At block 550, the UE 104 may add a compensation value to the measured RSRP, then proceed to block 560. At block 560, the UE may evaluate one or more event reporting conditions. The event reporting conditions may be events configured for the UE 104. In an aspect, the event reporting conditions may include an event 3A indicating that a signal strength of a neighbor cell has become greater than the signal strength of the serving cell by an offset and/or an event 4A indicating that the signal strength of a neighbor cell has become greater than a threshold. The 5G anchor cells may be more likely to satisfy the event reporting condition due to the compensation value added to the measured RSRP. If the measured cell fails the event reporting condition, the UE 104 may return to block 520. If the measured cell passes the event reporting condition, the UE 104 may proceed to block 570. At block 570, the UE may transmit a measurement report. The measurement report may include an indication of the event reporting condition. At block 580, the UE may perform a handover to a 5G anchor cell. For example, the UE may receive a handover command from the current serving cell and begin receiving on the frequency of the 5G anchor cell.

FIG. 6 is a conceptual data flow diagram 600 illustrating the data flow between different means/components in an example UE 604, which may be an example of the UE 104 and include the handover component 140.

The receiver component 470 may receive downlink signals such as the configuration message 410 and reference signals 420 from one or more base stations 102. The receiver component 470 may provide the configuration message to the configuration component 141. The receiver component 470 may provide the reference signals 420 to the measurement component 143. The receiver component 470 also may receive a handover command 450 indicating a new serving cell. The receiver component 470 may provide the handover command 450 to the configuration component 141.

The configuration component 141 may receive the configuration message 410 from the receiver component 470. The configuration component 141 may extract the neighbor cell list 412 from the configuration message 410. The neighbor cell list 412 may be a list of frequencies of neighbor cells. The configuration component 141 may provide the neighbor cell list 412 to the measurement component 143 and the anchor band component 142. The configuration component 141 also may receive a configuration of event reporting conditions 630. The configuration of event reporting conditions 630 may be in the configuration message 410 or another message. The configuration of event reporting conditions 630 may indicate which events are configured as well as event parameters such as an offset for event 3A or a threshold for event 4A. The configuration component 141 may configure the evaluation component 146 with the event reporting conditions. When the configuration component 141 receives the handover command 450, the configuration component 141 may configure the UE 604 for communication with the new serving cell.

The anchor band component 142 may receive the neighbor cell list 412 from the configuration component 141. The anchor band component 142 may determine whether each neighbor cell is a 5G anchor cell. In particular, the anchor band component 142 may determine whether a frequency of a neighbor cell is within a 5G anchor band 610. The anchor band component 142 may determine the 5G anchor band based on a network operator 612. For example, the handover component 140 may be configured with a list of anchor bands 610 for different network operators according to a mobile country code (MCC) and mobile network code (MNC) . The anchor bands may be based on licensing information for the different network operators. In some implementations, the anchor bands 610 may be configured within the firmware of the UE 104 and/or the handover component 140 and may be updated via a system update for the UE 104. The anchor band component 142 may provide an indication of the 5G anchor cells to the threshold component 144 and the compensation component 145.

The measurement component 143 may receive the reference signals 420 from the receiver component 470. The reference signals 420 may be received periodically while operating in the idle mode. The measurement component 143 may receive the neighbor cell list 412 from the configuration component 141. The measurement component 143 may determine a signal strength for each cell on the neighbor cell list 412. In an aspect, the measurement component 143 may determine a RSRP 620 for LTE cells including the 5G anchor cells. For legacy cells, the measurement component 143 may determine a signal strength such as a common pilot channel (CPICH) received energy per chip to total received power ratio (Ec/No) or a pilot-common control physical channel (P-CCPCH) received signal code power (RSCP) . The measurement component 143 may provide the measured signal strengths, including RSRP 620 for the 5G anchor cells, to the threshold component 144.

The threshold component 144 may receive the indication of the 5G anchor cells from the anchor band component and the signal strength from the measurement component 143. For each 5G anchor cell, the threshold component 144 may compare the signal strength to the minimum threshold 622. The minimum threshold 622 may be a minimum acceptable signal strength for the UE 104. In some implementations, the minimum threshold 622 may be configured within the firmware of the UE 104 and/or the handover component 140 and may be updated via a system update for the UE 104. In some implementations, the minimum threshold 622 may have a value between -110 dBm and -100 In some implementations, the minimum threshold 622 may be based on a network configured threshold such as a threshold for event A2, where the serving cell becoming worse than the threshold would be reported. If the signal strength for a 5G anchor cell satisfies the minimum threshold 622, the threshold component 144 may pass the signal strength to the compensation component 145.

The compensation component 145 may receive the signal strength for a 5G anchor cell from the threshold component 144. The compensation component 145 may add the compensation value 624 to the signal strength to determine a compensated signal strength. The compensation value 624 may be a positive compensation to induce a handover to the 5G anchor cell. For example, the compensation value 624 may be between 2 dB and 20 dB. In some implementations, the compensation value 624 may be between 3 dB and 5 dB. In some implementations, the compensation value 624 may be 15 dB. In some implementations, the compensation value 624 may account for RF performance defects in some bands and may be defined per band. Generally, a higher value of the compensation value 624 will be more likely to induce a handover to the 5G anchor cell. The compensation component 145 may provide the compensated signal strength to the evaluation component 146.

The evaluation component 146 may receive the compensated signal strength from the compensation component 145. The evaluation component 146 may determine whether the anchor neighbor cell satisfies any event reporting conditions 630 based on the compensated signal strength. For example, for event 3A, the evaluation component 146 may compare the compensated signal strength with the signal strength of the serving cell plus an offset. As another example, for event 4A, the evaluation component 146 may compare the compensated signal strength a threshold configured for event 4A. In some implementations, a 5G anchor cell with an RSRP 620 that would not satisfy the event reporting conditions 630 may satisfy the event reporting conditions 630 based on the addition of the compensation value 624. Accordingly, the handover component 140 may increase the likelihood that the UE 104 will generate a measurement report for the anchor neighbor cell. The evaluation component 146 may indicate the event corresponding to the satisfied event reporting conditions 630 to the reporting component 147,

The reporting component 147 may receive the indication of the event from the evaluation component 146. The reporting component 147 may generate a measurement report 440 based on the event. The measurement report 440 may include an indication of the event triggering the measurement report and measurement values associated with the event. For example, the measurement report 440 may include a cell identifier of the anchor neighbor cell and the compensated signal strength. The reporting component 147 may transmit the measurement report 440 to the current serving cell via the transmitter component 472. The receiver component 470 may receive the handover command 450 in response to the measurement report 440.

FIG. 7 is a flowchart of an example method 700 for inducing a handover to a 5G anchor cell. The method 700 may be performed by a UE (such as the UE 104, which may include the memory 360 and which may be the entire UE 104 or a component of the UE 104 such as the handover component 140, TX processor 368, the RX processor 356, or the controller/processor 359) . The method 700 may be performed by the handover component 140 in communication with a serving cell component 198 of the base station 102. The method 700 may be performed while the UE 104 is in the connected mode with the base station 102.

At block 710, the method 700 may include receiving, from the serving cell, a neighbor cell list indicating a plurality of neighbor cells. In an aspect, for example, the UE 104, the RX processor 356 and/or the controller/processor 359 may execute the handover component 140 and/or the configuration component 141 to receive the neighbor cell list 412 indicating the plurality of neighbor cells. For example, at sub-block 712, the block 710 may optionally include receiving a list of 4G neighbor cells in a configuration message from the serving cell. In an aspect, at sub-block 714, the block 710 may optionally include receiving a configuration of event reporting conditions 630. For instance, the event reporting conditions may be indicated in the configuration message. Accordingly, the UE 104, the RX processor 356, and/or the controller/processor 359 executing the handover component 140 and/or the configuration component 141 may provide means for receiving a neighbor cell list indicating a plurality of neighbor cells.

At block 720, the method 700 may include determining that a frequency of at least one anchor neighbor cell on the neighbor cell list corresponds to a frequency band supporting a 5G non-stand-alone network. In an aspect, for example, the UE 104, the RX processor 356 and/or the controller/processor 359 may execute the handover component 140 and/or the anchor band component 142 to determine that a frequency of at least one anchor neighbor cell on the neighbor cell list corresponds to a frequency band supporting a 5G non-stand-alone network. For instance, at sub-block 722, the block 720 may optionally include determining the frequency band supporting the 5G non-stand-alone network based on a network operator. That is, the anchor band component 142 may determine an operator of the current serving cell, for example, as indicated by a MCC and MNC, and look up one or more corresponding anchor bands for the network operator. Accordingly, the UE 104, the RX processor 356, and/or the controller/processor 359 executing the handover component 140 and/or the anchor band component 142 may provide means for determining that a frequency of at least one anchor neighbor cell on the neighbor cell list corresponds to a frequency band supporting a 5G non-stand-alone network.

At block 730, the method 700 may include measuring a signal strength of the at least one anchor neighbor cell. In an aspect, for example, the UE 104, the RX processor 356 and/or the controller/processor 359 may execute the handover component 140 and/or the measurement component 143 to measure a signal strength of the at least one anchor neighbor cell. In some implementations, the measurement component 143 may measure each of the plurality of neighbor cells. For example, for an LTE cell including 5G anchor cells, the signal strength may be the RSRP 620. For legacy cells, the signal strength may be a CPICH Ec/No or a P-CCPCH RSCP. Accordingly, the UE 104, the RX processor 356, and/or the controller/processor 359 executing the handover component 140 and/or the measurement component 143 may provide means for measuring a signal strength of the at least one anchor neighbor cell.

At block 740, the method 700 may include determining that the signal strength of an anchor neighbor cell satisfies a minimum threshold. In an aspect, for example, the UE 104, the RX processor 356 and/or the controller/processor 359 may execute the handover component 140 and/or the threshold component 144 to determine that the signal strength (e.g., RSRP 620) of the anchor neighbor cell satisfies the minimum threshold 622. For instance, in some implementations, the minimum threshold 622 the minimum threshold is between -110 dBm and -100 dBm. Accordingly, the UE 104, the RX processor 356, and/or the controller/processor 359 executing the handover component 140 and/or the threshold component 144 may provide means for determining that the signal strength of an anchor neighbor cell satisfies a minimum threshold.

At block 750, the method 700 may include adding a compensation value to the signal strength of the anchor neighbor cell to determine a compensated signal strength. The block 750 may be in response to the determination that the signal strength of the anchor neighbor cell satisfies the minimum threshold in block 740. In an aspect, for example, the UE 104, the RX processor 356 and/or the controller/processor 359 may execute the handover component 140 and/or the threshold component 144 to add the compensation value 624 to the signal strength (e.g., RSRP 620) of the anchor neighbor cell to determine a compensated signal strength. For instance, in some implementations, the compensation value 624 is between 2 dB and 20 dB. Accordingly, the UE 104, the RX processor 356, and/or the controller/processor 359 executing the handover component 140 and/or the compensation component 145 may provide means for adding a compensation value to the signal strength of the anchor neighbor cell to determine a compensated signal strength in response to the determination that the signal strength of the anchor neighbor cell satisfies the minimum threshold.

At block 760, the method 700 may include determining that the anchor neighbor cell satisfies an event reporting condition based on the compensated signal strength. In an aspect, for example, the UE 104, the RX processor 356 and/or the controller/processor 359 may execute the handover component 140 and/or the evaluation component 146 to determine that the anchor neighbor cell satisfies one or more of the event reporting conditions 630 based on the compensated signal strength. For instance, in some implementations, the event reporting conditions 630 correspond to an event 3A where the event reporting condition is satisfied when the compensated signal strength of the anchor neighbor cell is better than a signal strength of the serving cell by an offset. In some instances, the signal strength of the anchor neighbor cell without the compensation value 624 is less than the signal strength of the serving cell. In some implementations, the event reporting conditions 630 correspond to an event 4A where the event reporting condition is satisfied when the compensated signal strength of the anchor neighbor cell is better than an event threshold. Accordingly, the UE 104, the RX processor 356, and/or the controller/processor 359 executing the handover component 140 and/or the evaluation component 146 may provide means for determining that the anchor neighbor cell satisfies an event reporting condition based on the compensated signal strength.

At block 770, the method 700 may include transmitting a measurement report to the serving cell in response to the determination that the anchor neighbor cell satisfies the event reporting condition. In an aspect, for example, the UE 104, the RX processor 356 and/or the controller/processor 359 may execute the handover component 140 and/or the reporting component 147 to transmit the measurement report 440 to the serving cell in response to the determination that the anchor neighbor cell satisfies the event reporting condition 630. Accordingly, the UE 104, the RX processor 356, and/or the controller/processor 359 executing the handover component 140 and/or the configuration component 141 may provide means for transmitting a measurement report to the serving cell in response to the determination that the anchor neighbor cell satisfies the event reporting condition.

At block 780, the method 700 may include receiving a handover command from the serving cell for a handover to the anchor neighbor cell in response to the measurement report. In an aspect, for example, the UE 104, the RX processor 356 and/or the controller/processor 359 may execute the handover component 140 and/or the receiver component 470 to receive the handover command 450 from the serving cell (e.g., base station 102-a) for a handover to the anchor neighbor cell in response to the measurement report 440. Accordingly, the UE 104, the RX processor 356, and/or the controller/processor 359 executing the handover component 140 and/or the receiver component 470 may provide means for receiving a handover command from the serving cell for a handover to the anchor neighbor cell in response to the measurement report.

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 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. ” 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 for a user equipment (UE) , comprising:

receiving, from a serving cell, a neighbor cell list indicating a plurality of neighbor cells;

determining that a frequency of at least one anchor neighbor cell on the neighbor cell list corresponds to a frequency band supporting a 5G non-stand-alone network;

measuring a signal strength of the at least one anchor neighbor cell;

determining that the signal strength of an anchor neighbor cell satisfies a minimum threshold;

adding a compensation value to the signal strength of the anchor neighbor cell to determine a compensated signal strength in response to the determination that the signal strength of the anchor neighbor cell satisfies the minimum threshold;

determining that the anchor neighbor cell satisfies an event reporting condition based on the compensated signal strength;

transmitting a measurement report to the serving cell in response to the determination that the anchor neighbor cell satisfies the event reporting condition; and

receiving a handover command for a handover to the anchor neighbor cell in response to the measurement report.
The method of claim 1, wherein determining that the frequency of the at least one anchor neighbor cell in the neighbor cell list corresponds to the frequency band supporting the 5G non-stand-alone network comprises determining the frequency band supporting the 5G non-stand-alone network based on a network operator.
The method of claim 1, wherein the minimum threshold is between -110 dBm and -100 dBm.
The method of claim 1, wherein the compensation value is between 2 dB and 20 dB.
The method of claim 1, wherein the event reporting condition is satisfied when the compensated signal strength of the anchor neighbor cell is better than a signal strength of the serving cell by an offset.
The method of claim 5, wherein the signal strength of the anchor neighbor cell without the compensation value is less than the signal strength of the serving cell.
The method of claim 1, wherein the event reporting condition is satisfied when the compensated signal strength of the anchor neighbor cell is better than an event threshold.
The method of claim 1, wherein the signal strength is a reference signal received power (RSRP) .
An apparatus for wireless communication, comprising:

a memory storing computer-executable instructions; and

at least one processor coupled to the memory and configured to execute the computer-executable instructions to perform the method of any of claims 1-8.
An apparatus for wireless communication, comprising:

means for performing the method of any of claims 1-8.
A non-transitory computer-readable medium storing computer executable code, the code when executed by a processor causes the processor to perform the method of any of claims 1-8.