WO2016090609A1

WO2016090609A1 - Neighbor cell measurements for high-speed user equipment

Info

Publication number: WO2016090609A1
Application number: PCT/CN2014/093610
Authority: WO
Inventors: Ming Yang; Hui Zhao; Xiaoping Wu; Yilan SUN
Original assignee: Qualcomm Incorporated
Priority date: 2014-12-11
Filing date: 2014-12-11
Publication date: 2016-06-16

Abstract

In some aspects, a user equipment (UE) for wireless communication may determine a speed of the UE. The UE may determine, based on the speed, an amount of time to wait before measuring a parameter of a communication with a neighbor base station. The UE may measure the parameter of the communication with the neighbor base station after waiting the amount of time.

Description

NEIGHBOR CELL MEASUREMENTS FOR HIGH-SPEED USER EQUIPMENT

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communications, and more particularly to techniques and apparatuses for measuring parameters of neighbor base stations when a user equipment (UE) is travelling at a high speed.

BACKGROUND

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 (e.g., bandwidth, transmit power, etc. ) . 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 divisional 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 of a telecommunication standard is Long Term Evolution (LTE) . LTE is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by Third Generation Partnership Project (3GPP) . LTE is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, using new spectrum, and integrating with other open standards using OFDMA on the downlink (DL) , SC-FDMA on the uplink (UL) , and multiple-input multiple-output (MIMO) antenna technology.

SUMMARY

In some aspects, a method for wireless communication may include determining, by a user equipment (UE) , a speed of the UE. The method may include determining, by the UE and based on the speed, an amount of time to wait before measuring a parameter of a communication with a neighbor base station. The method may include measuring, by the UE and after waiting the amount of time, the parameter of the communication with the neighbor base station.

In some aspects, a user equipment (UE) for wireless communication may comprise one or more processors configured to determine a speed of the UE, determine, based on the speed, an amount of time to wait before measuring a parameter of a communication with a neighbor base station, and measure the parameter of the communication with the neighbor base station after waiting the amount of time.

In some aspects, a non-transitory computer-readable medium may include instructions for wireless communication. The instructions may cause a processor of a user equipment (UE) to determine a speed of the UE, to determine, based on the speed, an amount of time to wait before measuring a parameter of a communication with a neighbor base station, and to measure the parameter of the communication with the neighbor base station after waiting the amount of time.

In some aspects, an apparatus for wireless communication may include means for determining a speed of a user equipment (UE) , a means for determining, based on the speed, an amount of time to wait before measuring a parameter of a communication with a neighbor base station, and a means for measuring the parameter of the communication with the neighbor base station after waiting the amount of time.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, and user equipment as substantially described herein with reference to and as illustrated by the accompanying drawings.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purpose of illustration and description, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements.

Fig. 1 is a diagram illustrating an example deployment in which multiple wireless networks have overlapping coverage, in accordance with various aspects of the present disclosure.

Fig. 2 is a diagram illustrating an example access network in an LTE network architecture, in accordance with various aspects of the present disclosure.

Fig. 3 is a diagram illustrating an example of a downlink frame structure in LTE, in accordance with various aspects of the present disclosure.

Fig. 4 is a diagram illustrating an example of an uplink frame structure in LTE, in accordance with various aspects of the present disclosure.

Fig. 5 is a diagram illustrating an example of a radio protocol architecture for a user plane and a control plane in LTE, in accordance with various aspects of the present disclosure.

Fig. 6 is a diagram illustrating example components of an evolved Node B and a user equipment in an access network, in accordance with various aspects of the present disclosure.

Figs. 7A and 7B are diagrams illustrating an overview of example aspects described herein, in accordance with various aspects of the present disclosure.

Fig. 8 is a diagram illustrating an example process performed, for example, by a user equipment, in accordance with various aspects of the present disclosure.

Fig. 9 is a diagram illustrating an example of the process illustrated in Fig. 8, in accordance with various aspects of the present disclosure.

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 providing a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details.

The techniques described herein may be used for one or more of various wireless communication networks such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single carrier FDMA (SC-FDMA) networks, or other types of networks. A CDMA network may implement a radio access technology (RAT) such as universal terrestrial radio access (UTRA) , CDMA2000, or the like. UTRA may include wideband CDMA (WCDMA) and/or other variants of CDMA. CDMA2000 may include Interim Standard (IS) -2000, IS-95 and IS-856 standards. IS-2000 may also be referred to as 1x radio transmission technology (1xRTT) , CDMA2000 1X, or the like. A TDMA network may implement a RAT such as global system for mobile communications (GSM) , enhanced data rates for GSM evolution (EDGE) , or GSM/EDGE radio access network (GERAN) . An OFDMA network may implement a RAT such as evolved UTRA (E-UTRA) , ultra mobile broadband (UMB) , Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi- Fi), IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM, or the like. UTRA and E-UTRA may be part of the universal mobile telecommunication system (UMTS) . 3GPP long-term evolution (LTE) and LTE-Advanced (LTE-A) are example releases of UMTS that use E-UTRA, which employs OFDMA on the downlink and SC-FDMA on the uplink. UTRA, E-UTRA, UMTS, LTE, LTE-Aand GSM are described in documents from an organization named “3rd Generation Partnership Project” (3GPP) . CDMA2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2) . The techniques described herein may be used for the wireless networks and RATs mentioned above as well as other wireless networks and RATs.

Fig. 1 is a diagram illustrating an example deployment 100 in which multiple wireless networks have overlapping coverage, in accordance with various aspects of the present disclosure. As shown, example deployment 100 may include a dedicated radio access network (RAN) 105, which may include one or more evolved Node Bs (eNBs) 110, and which may communicate with other devices or networks via a serving gateway (SGW) 115 and/or a mobility management entity (MME) 120. As further shown, example deployment 100 may include a public RAN 125, which may include one or more eNBs 130, and which may communicate with other devices or networks via an MME 135 and/or an inter-working function (IWF) 140. In some aspects, dedicated RAN 105 may be a non-public RAN or may be a public RAN. In some aspects, public RAN 125 may be a non-public RAN or may be a dedicated RAN. As further shown, example deployment 100 may include one or more user equipments (UEs) 145 capable of communicating via dedicated RAN 105 and/or public RAN 125.

Dedicated RAN 105 may support LTE or another type of RAT and may include eNBs 110 and other network entities that can support wireless communication for UEs 145. Each eNB 110 may provide communication coverage for a particular geographic area. The term “cell” may refer to a coverage area of eNB 110 and/or an eNB subsystem serving the coverage area.

SGW 115 may communicate with dedicated RAN 105 and may perform various functions, such as packet routing and forwarding, mobility anchoring, packet buffering, initiation of network-triggered services, or the like. MME 120 may communicate with dedicated RAN 105 and SGW 115 and may perform various functions, such as mobility management, bearer management, distribution of paging messages, security control, authentication, gateway selection, or the like, for UEs 145 located within a geographic region served by MME 120 of dedicated RAN 105. The network entities in LTE are described in 3GPP TS 36.300, entitled “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN) ； Overall description, ” which is publicly available.

Public RAN 125 may support LTE or another type of RAT and may include eNBs 130 and other network entities that can support wireless communication for UEs 145. MME 135 may communicate with public RAN 125 and may perform various functions, such as mobility management, bearer management, distribution of paging messages, security control, authentication, gateway selection, or the like, for UEs 145 located within a geographic region served by MME 135 of public RAN 125. In some aspects, IWF 140 may facilitate communication between MME 120 and MME 135 (e.g., when dedicated RAN 105 and public RAN 125 use different RATs) . Additionally, or alternatively, MME 120 and MME 135 may communicate directly without IWF 140 (e.g., when dedicated RAN 105 and public RAN 125 use a same RAT) .

In some aspects, dedicated RAN 105 may be reserved for particular UEs 145, such as UEs 145 travelling at high speeds. For example, eNBs 110 of dedicated RAN 105 may be located along or proximate to a path of a train (e.g., along train tracks) , along or proximate to a path of a subway, or along or proximate to the path of another vehicle capable of travelling at high speeds (e.g.， speeds greater than a threshold, such as 150 kilometers per hour (kph) ) . Conversely, public RAN 125 may not be reserved for UEs 145 travelling at high speeds, and may be accessible by other UEs 145. In this case, dedicated RAN 105 and public RAN 125 may use different frequencies to communicate with UEs 145.

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, etc. A frequency or frequency ranges may also be referred to as a carrier, a frequency channel, or the like. Each frequency or frequency range may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs.

UE 145 may be stationary or mobile and may also be referred to as a mobile station, a terminal, an access terminal, a subscriber unit, a station, or the like. UE 145 may be a cellular phone, a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, etc.

Upon power up, UE 145 may search for wireless networks from which UE 145 can receive communication services. If UE 145 detects more than one wireless network, then a wireless network with the highest priority may be selected to serve UE 145 and may be referred to as the serving network. UE 145 may perform registration with the serving network, if necessary. UE 145 may then operate in a connected mode to actively communicate with the serving network. Alternatively, UE 145 may operate in an idle mode and camp on the serving network if active communication is not required by UE 145.

UE 145 may operate in the idle mode as follows. UE 145 may identify all frequencies/RATs on which it is able to find a "suitable"cell in a normal scenario or an “acceptable” cell in an emergency scenario, where “suitable” and “acceptable” are specified in the LTE standards. UE 145 may then camp on the frequency/RAT with the highest priority among all identified frequencies/RATs. UE 145 may remain camped on this frequency/RAT until either (i) the frequency/RAT is no longer available at a predetermined threshold or (ii) another frequency/RAT with a higher priority reaches this threshold. This operating behavior for UE 145 in the idle mode is described in 3GPP TS 36.304, entitled “Evolved Universal Terrestrial Radio Access (E-UTRA) ； User Equipment (UE) procedures in idle mode, ” which is publicly available.

The number and arrangement of devices and networks shown in Fig. 1 are provided as an example. In practice, there may be additional devices and/or networks, fewer devices and/or networks, different devices and/or networks, or differently arranged devices and/or networks than those shown in Fig. 1. Furthermore, two or more devices shown in Fig. 1 may be implemented within a single device, or a single device shown in Fig. 1 may be implemented as multiple, distributed devices. Additionally, or alternatively, a set of devices (e.g., one or more devices) shown in Fig. 1 may perform one or more functions described as being performed by another set of devices shown in Fig. 1.

Fig. 2 is a diagram illustrating an example access network 200 in an LTE network architecture, in accordance with various aspects of the present disclosure. As shown, access network 200 may include a set of eNBs 210 that serve a corresponding set of cellular regions (cells) 220, a set of low power eNBs 230 that serve a corresponding set of cells 240, and a set of UEs 250.

Each eNB 210 may be assigned to a respective cell 220 and may be configured to provide an access point to a RAN. For example, eNB 210 may provide an access point for UE 250 to dedicated RAN 105 (e.g., eNB 210 may correspond to eNB 110, shown in Fig. 1) or may provide an access point for UE 250 to public RAN 125 (e.g., eNB 210 may correspond to eNB 130, shown in Fig. 1) . UE 250 may correspond to UE 145, shown in Fig. 1. Fig. 2 does not illustrate a centralized controller for example access network 200, but access network 200 may use a centralized controller in some aspects. The eNBs 210 may perform radio related functions including radio bearer control, admission control, mobility control, scheduling, security, and network connectivity (e.g., to SGW 115) .

As shown in Fig. 2, one or more low power eNBs 230 may serve respective cells 240, which may overlap with one or more cells 230 served by eNBs 210. The eNBs 230 may correspond to eNB 110 associated with dedicated RAN 105 and/or eNB 130 associated with public RAN 125, shown in Fig. 1. A low power eNB 230 may be referred to as a remote radio head (RRH) . The low power eNB 230 may include a femto cell eNB (e.g., home eNB (HeNB) ) , a pico cell eNB, a micro cell eNB, or the like.

A modulation and multiple access scheme employed by access network 200 may vary depending on the particular telecommunications standard being deployed. In LTE applications, OFDM is used on the downlink (DL) and SC-FDMA is used on the uplink (UL) to support both frequency division duplexing (FDD) and time division duplexing (TDD) . The various concepts presented herein are well suited for LTE applications. However, these concepts may be readily extended to other telecommunication standards employing other modulation and multiple access techniques. By way of example, these concepts may be extended to Evolution-Data Optimized (EV-DO) or Ultra Mobile Broadband (UMB) . EV-DO and UMB are air interface standards promulgated by the 3rd Generation Partnership Project 2 (3GPP2) as part of the CDMA2000 family of standards and employs CDMA to provide broadband Internet access to mobile stations. As another example, these concepts may also be extended to UTRA employing WCDMA and other variants of CDMA (e.g., such as TD-SCDMA, GSM employing TDMA, E-UTRA, or the like) , UMB, IEEE 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM employing OFDMA, or the like. UTRA, E-UTRA, UMTS, LTE and GSM are described in documents from the 3GPP organization. CDMA2000 and UMB are described in documents from the 3GPP2 organization. The actual wireless communication standard and the multiple access technology employed will depend on the specific application and the overall design constraints imposed on the system.

The eNBs 210 may have multiple antennas supporting MIMO technology. The use of MIMO technology enables eNBs 210 to exploit the spatial domain to support spatial multiplexing, beamforming, and transmit diversity. Spatial multiplexing may be used to transmit different streams of data simultaneously on the same frequency. The data streams may be transmitted to a single UE 250 to increase the data rate or to multiple UEs 250 to increase the overall system capacity. This may be achieved by spatially precoding each data stream (e.g., applying a scaling of an amplitude and a phase) and then transmitting each spatially precoded stream through multiple transmit antennas on the DL. The spatially precoded data streams arrive at the UE (s) 250 with different spatial signatures, which enables each of the UE (s) 250 to recover the one or more data streams destined for that UE 250. On the UL, each UE 250 transmits a spatially precoded data stream, which enables eNB 210 to identify the source of each spatially precoded data stream.

Spatial multiplexing is generally used when channel conditions are good. When channel conditions are less favorable, beamforming may be used to focus the transmission energy in one or more directions. This may be achieved by spatially precoding the data for transmission through multiple antennas. To achieve good coverage at the edges of the cell, a single stream beamforming transmission may be used in combination with transmit diversity.

In the detailed description that follows, various aspects of an access network will be described with reference to a MIMO system supporting OFDM on the DL. OFDM is a spread-spectrum technique that modulates data over a number of subcarriers within an OFDM symbol. The subcarriers are spaced apart at precise frequencies. The spacing provides “orthogonality” that enables a receiver to recover the data from the subcarriers. In the time domain, a guard interval (e.g., cyclic prefix) may be added to each OFDM symbol to combat inter-OFDM-symbol interference. The UL may use SC-FDMA in the form of a DFT-spread OFDM signal to compensate for high peak-to-average power ratio (PAPR) .

The number and arrangement of devices and cells shown in Fig. 2 are provided as an example. In practice, there may be additional devices and/or cells, fewer devices and/or cells, different devices and/or cells, or differently arranged devices and/or cells than those shown in Fig. 2. Furthermore, two or more devices shown in Fig. 2 may be implemented within a single device, or a single device shown in Fig. 2 may be implemented as multiple, distributed devices. Additionally, or alternatively, a set of devices (e.g., one or more devices) shown in Fig. 2 may perform one or more functions described as being performed by another set of devices shown in Fig. 2.

Fig. 3 is a diagram illustrating an example 300 of a downlink (DL) frame structure in LTE. A frame (e.g., of 10 ms) may be divided into 10 equally sized sub-frames with indices of 0 through 9. Each sub-frame may include two consecutive time slots. A resource grid may be used to represent two time slots, each time slot including a resource block (RB) . The resource grid is divided into multiple resource elements. In LTE, a resource block contains 12 consecutive subcarriers in the frequency domain and, for a normal cyclic prefix in each OFDM symbol, 7 consecutive OFDM symbols in the time domain, or 84 resource elements. For an extended cyclic prefix, a resource block contains 6 consecutive OFDM symbols in the time domain and has 72 resource elements. Some of the resource elements, as indicated as R 310 and R 320, include DL reference signals (DL-RS) . The DL-RS include Cell-specific RS (CRS) (also sometimes called common RS) 310 and UE-specific RS (UE-RS) 320. UE-RS 320 are transmitted only on the resource blocks upon which the corresponding physical DL shared channel (PDSCH) is mapped. The number of bits carried by each resource element depends on the modulation scheme. Thus, the more resource blocks that a UE receives and the higher the modulation scheme, the higher the data rate for the UE.

In LTE, an eNB may send a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) for each cell in the eNB. The primary and secondary synchronization signals may be sent in

symbol periods

6 and 5, respectively, in each of

subframes

0 and 5 of each radio frame with the normal cyclic prefix (CP) . The synchronization signals may be used by UEs for cell detection and acquisition. The eNB may send a Physical Broadcast Channel (PBCH) in symbol periods 0 to 3 in slot 1 of subframe 0. The PBCH may carry certain system information.

The eNB may send a Physical Control Format Indicator Channel (PCFICH) in the first symbol period of each subframe. The PCFICH may convey the number of symbol periods (M) used for control channels, where M may be equal to 1, 2 or 3 and may change from subframe to subframe. M may also be equal to 4 for a small system bandwidth, e.g., with less than 10 resource blocks. The eNB may send a Physical HARQ Indicator Channel (PHICH) and a Physical Downlink Control Channel (PDCCH) in the first M symbol periods of each subframe. The PHICH may carry information to support hybrid automatic repeat request (HARQ) . The PDCCH may carry information on resource allocation for UEs and control information for downlink channels. The eNB may send a Physical Downlink Shared Channel (PDSCH) in the remaining symbol periods of each subframe. The PDSCH may carry data for UEs scheduled for data transmission on the downlink.

The eNB may send the PSS, SSS, and PBCH in the center 1.08 MHz of the system bandwidth used by the eNB. The eNB may send the PCFICH and PHICH across the entire system bandwidth in each symbol period in which these channels are sent. The eNB may send the PDCCH to groups of UEs in certain portions of the system bandwidth. The eNB may send the PDSCH to specific UEs in specific portions of the system bandwidth. The eNB may send the PSS, SSS, PBCH, PCFICH, and PHICH in a broadcast manner to all UEs, may send the PDCCH in a unicast manner to specific UEs, and may also send the PDSCH in a unicast manner to specific UEs.

A number of resource elements may be available in each symbol period. Each resource element (RE) may cover one subcarrier in one symbol period and may be used to send one modulation symbol, which may be a real or complex value. Resource elements not used for a reference signal in each symbol period may be arranged into resource element groups (REGs) . Each REG may include four resource elements in one symbol period. The PCFICH may occupy four REGs, which may be spaced approximately equally across frequency, in symbol period 0. The PHICH may occupy three REGs, which may be spread across frequency, in one or more configurable symbol periods. For example, the three REGs for the PHICH may all belong in symbol period 0 or may be spread in

symbol periods

0, 1, and 2. The PDCCH may occupy 9, 18, 36, or 72 REGs, which may be selected from the available REGs, in the first M symbol periods, for example. Only certain combinations of REGs may be allowed for the PDCCH.

A UE may know the specific REGs used for the PHICH and the PCFICH. The UE may search different combinations of REGs for the PDCCH. The number of combinations to search is typically less than the number of allowed combinations for the PDCCH. An eNB may send the PDCCH to the UE in any of the combinations that the UE will search.

As indicated above, Fig. 3 is provided as an example. Other examples are possible and may differ from what was described above in connection with Fig. 3.

Fig. 4 is a diagram illustrating an example 400 of an uplink (UL) frame structure in LTE. The available resource blocks for the UL may be partitioned into a data section and a control section. The control section may be formed at the two edges of the system bandwidth and may have a configurable size. The resource blocks in the control section may be assigned to UEs for transmission of control information. The data section may include all resource blocks not included in the control section. The UL frame structure results in the data section including contiguous subcarriers, which may allow a single UE to be assigned all of the contiguous subcarriers in the data section.

A UE may be assigned

resource blocks

410a, 410b in the control section to transmit control information to an eNB. The UE may also be assigned

resource blocks

420a, 420b in the data section to transmit data to the eNB. The UE may transmit control information in a physical UL control channel (PUCCH) on the assigned resource blocks in the control section. The UE may transmit only data or both data and control information in a physical UL shared channel (PUSCH) on the assigned resource blocks in the data section. A UL transmission may span both slots of a subframe and may hop across frequencies.

A set of resource blocks may be used to perform initial system access and achieve UL synchronization in a physical random access channel (PRACH) 430. The PRACH 430 carries a random sequence and cannot carry any UL data/signaling. Each random access preamble occupies a bandwidth corresponding to six consecutive resource blocks. The starting frequency is specified by the network. That is, the transmission of the random access preamble is restricted to certain time and frequency resources. There is no frequency hopping for the PRACH. The PRACH attempt is carried in a single subframe (e.g., of 1 ms) or in a sequence of few contiguous subframes and a UE can make only a single PRACH attempt per frame (e.g., of 10 ms) .

As indicated above, Fig. 4 is provided as an example. Other examples are possible and may differ from what was described above in connection with Fig. 4.

Fig. 5 is a diagram illustrating an example 500 of a radio protocol architecture for a user plane and a control plane in LTE. The radio protocol architecture for the UE and the eNB is shown with three layers: Layer 1, Layer 2, and Layer 3. Layer 1 (L1 layer) is the lowest layer and implements various physical layer signal processing functions. The L1 layer will be referred to herein as the physical layer 510. Layer 2 (L2 layer) 520 is above the physical layer 510 and is responsible for the link between the UE and eNB over the physical layer 510.

In the user plane, the L2 layer 520 includes a media access control (MAC) sublayer 530, a radio link control (RLC) sublayer 540, and a packet data convergence protocol (PDCP) 550 sublayer, which are terminated at the eNB on the network side. Although not shown, the UE may have several upper layers above the L2 layer 520 including a network layer (e.g., IP layer) that is terminated at a packet data network (PDN) gateway on the network side, and an application layer that is terminated at the other end of the connection (e.g., far end UE, server, etc. ) .

The PDCP sublayer 550 provides multiplexing between different radio bearers and logical channels. The PDCP sublayer 550 also provides header compression for upper layer data packets to reduce radio transmission overhead, security by ciphering the data packets, and handover support for UEs between eNBs. The RLC sublayer 540 provides segmentation and reassembly of upper layer data packets, retransmission of lost data packets, and reordering of data packets to compensate for out-of-order reception due to hybrid automatic repeat request (HARQ) . The MAC sublayer 530 provides multiplexing between logical and transport channels. The MAC sublayer 530 is also responsible for allocating the various radio resources (e.g., resource blocks) in one cell among the UEs. The MAC sublayer 530 is also responsible for HARQ operations.

In the control plane, the radio protocol architecture for the UE and eNB is substantially the same for the physical layer 510 and the L2 layer 520 with the exception that there is no header compression function for the control plane. The control plane also includes a radio resource control (RRC) sublayer 560 in Layer 3 (L3 layer) . The RRC sublayer 560 is responsible for obtaining radio resources (i.e., radio bearers) and for configuring the lower layers using RRC signaling between the eNB and the UE.

As indicated above, Fig. 5 is provided as an example. Other examples are possible and may differ from what was described above in connection with Fig. 5.

Fig. 6 is a diagram illustrating example components 600 of eNB 210 and UE 250 in an access network, in accordance with various aspects of the present disclosure. As shown in Fig. 6, eNB 210 may include a controller/processor 605, a TX processor 610, a channel estimator 615, an antenna 620, a transmitter 625TX, a receiver 625RX, an RX processor 630, and a memory 635. As further shown in Fig. 6, UE 250 may include a receiver 640RX, a transmitter 640TX, an antenna 645, an RX processor 650, a channel estimator 655, a controller/processor 660, a memory 665, a data sink 670, a data source 675, and a TX processor 680.

In the DL, upper layer packets from the core network are provided to controller/processor 605. The controller/processor 605 implements the functionality of the L2 layer. In the DL, the controller/processor 605 provides header compression, ciphering, packet segmentation and reordering, multiplexing between logical and transport channels, and radio resource allocations to the UE 250 based on various priority metrics. The controller/processor 605 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the UE 250.

The TX processor 610 implements various signal processing functions for the L1 layer (e.g., physical layer) . The signal processing functions includes coding and interleaving to facilitate forward error correction (FEC) at the UE 250 and 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 are then split into parallel streams. Each stream is then 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 615 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 250. Each spatial stream is then provided to a different antenna 620 via a separate transmitter 625TX. Each transmitter 625TX modulates an RF carrier with a respective spatial stream for transmission.

At the UE 250, each receiver 640RX receives a signal through its respective antenna 645. Each receiver 640RX recovers information modulated onto an RF carrier and provides the information to the receiver (RX) processor 650. The RX processor 650 implements various signal processing functions of the L1 layer. The RX processor 650 performs spatial processing on the information to recover any spatial streams destined for the UE 250. If multiple spatial streams are destined for the UE 250, the spatial streams may be combined by the RX processor 650 into a single OFDM symbol stream. The RX processor 650 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 eNB 210. These soft decisions may be based on channel estimates computed by the channel estimator 655. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the eNB 210 on the physical channel. The data and control signals are then provided to the controller/processor 660.

The controller/processor 660 implements the L2 layer. The controller/processor 660 can be associated with a memory 665 that stores program codes and data. The memory 665 may include a non-transitory computer-readable medium. In the UL, the control/processor 660 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the core network. The upper layer packets are then provided to a data sink 670, which represents all the protocol layers above the L2 layer. Various control signals may also be provided to the data sink 670 for L3 processing. The controller/processor 660 is also responsible for error detection using an acknowledgement (ACK) and/or negative acknowledgement (NACK) protocol to support HARQ operations.

In the UL, a data source 675 is used to provide upper layer packets to the controller/processor 660. The data source 675 represents all protocol layers above the L2 layer. Similar to the functionality described in connection with the DL transmission by the eNB 210, the controller/processor 660 implements the L2 layer for the user plane and the control plane by providing header compression, ciphering, packet segmentation and reordering, and multiplexing between logical and transport channels based on radio resource allocations by the eNB 210. The controller/processor 660 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the eNB 210.

Channel estimates derived by a channel estimator 655 from a reference signal or feedback transmitted by the eNB 210 may be used by the TX processor 680 to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor 680 are provided to different antenna 645 via separate transmitters 640TX. Each transmitter 640TX modulates an RF carrier with a respective spatial stream for transmission.

The UL transmission is processed at the eNB 210 in a manner similar to that described in connection with the receiver function at the UE 250. Each receiver 625RX receives a signal through its respective antenna 620. Each receiver 625RX recovers information modulated onto an RF carrier and provides the information to a RX processor 630. The RX processor 630 may implement the L1 layer.

The controller/processor 605 implements the L2 layer. The controller/processor 605 can be associated with a memory 635 that stores program code and data. The memory 635 may be referred to as a computer-readable medium. In the UL, the control/processor 605 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the UE 250. Upper layer packets from the controller/processor 605 may be provided to the core network. The controller/processor 605 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

One or more components of UE 250 may be configured to perform neighbor cell measurements based on a speed of UE 250, as described in more detail elsewhere herein. For example, the controller/processor 660 and/or other processors and modules of UE 250 may perform or direct operations, for example process 800 in Fig. 8, and/or other processes for the techniques described herein, for example. In some aspects, one or more of the components shown in Fig. 6 may be employed to perform example process 800 and/or other processes for the techniques (e.g., to perform neighbor cell measurements based on a speed of UE 250) described herein.

The number and arrangement of components shown in Fig. 6 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in Fig. 6. Furthermore, two or more components shown in Fig. 6 may be implemented within a single components, or a single components shown in Fig. 6 may be implemented as multiple, distributed components. Additionally, or alternatively, a set of components (e.g., one or more components) shown in Fig. 6 may perform one or more functions described as being performed by another set of components shown in Fig. 6.

Figs. 7A and 7B are diagrams illustrating an overview of an example aspect 700 described herein. As shown in Fig. 7A, assume that dedicated RAN 105 includes multiple eNBs 210 positioned to provide access to dedicated RAN 105 for a UE 250 located on a train that is travelling at a high speed. As further shown, assume that a UE 250 is in communication with a serving eNB 210a that provides access to dedicated RAN 105. Assume that the serving eNB 210a provides, to UE 250, information that identifies one or more eNBs 210 as neighbor eNBs (e.g., identifies eNB 210b as a neighbor eNB) that cover one or more respective neighbor cells adjacent to a serving cell covered by serving eNB 210a.

Using the information that identifies the one or more eNBs 210 as neighbor eNBs, assume that UE 250 performs neighbor cell measurements of communications with neighbor eNBs 210b. A neighbor cell measurement may measure, for example, a power parameter (e.g., a reference signal received power (RSRP) parameter, a received signal code power (RSCP) parameter, etc. ) of a communication with neighbor eNB 210b, a quality parameter (e.g., a reference signal received quality (RSRQ) parameter, a signal to noise ratio (SINR) , etc. ) , or the like. If the measured power parameter or the measured quality parameter associated with neighbor eNB 210b is below a threshold (e.g., for a threshold quantity of consecutive neighbor cell measurements, such as three consecutive neighbor cell measurements) , UE 250 may pause before performing another neighbor cell measurement, as shown.

However, when UE 250 pauses when travelling at a high speed, UE 250 may be located in a different geographic region when UE 250 attempts to perform another neighbor cell measurement. In this case, and as shown, UE 250 may not recognize any of the neighboring eNBs 210 (e.g., may not recognize eNBs 210c-e) because these eNBs 210c-e may be different from the neighbor eNBs 210b identified by serving eNB 210a. In the case where UE 250 does not recognize the neighboring eNBs 210c-e, UE 250 may perform an LTE power scan to select an eNB 210 via which to connect to a RAN (e.g., an eNB 210 with which UE 250 detects a high power parameter and/or a high quality parameter for a communication, as compared to communications with other eNBs 210) .

In some cases, UE 250 may select an eNB 210 associated with public RAN 125, shown as eNB 210f, such as when an eNB 210f associated with public RAN 125 has a higher power parameter or quality parameter than an eNB 210c-e associated with dedicated RAN 105. As shown, when UE 250 selects an eNB 210f associated with public RAN 125, UE 250 may disconnect from dedicated RAN 105. This behavior may be undesirable because dedicated RAN 105 may be designed to improve performance for UEs 250 travelling at high speeds, while public RAN 125 may not be designed in this manner. Furthermore, once UE 250 has left dedicated RAN 105 for public RAN 125, UE 250 may be less likely to reconnect to dedicated RAN 105 because serving eNBs 210 associated with public RAN 125 may only identify neighbor eNBs 210 associated with public RAN 125, thereby reducing or eliminating the possibility that UE 250 is handed over to an eNB 210 associated with dedicated RAN 105. Thus, by pausing before performing a neighbor cell measurement, UE 250 may reduce performance.

In accordance with various aspects of the present disclosure, and as shown in Fig. 7B, assume that UE 250 detects that UE 250 is travelling at a high rate of speed (e.g., greater than a threshold, such as 150 kph) . Based on this detection, UE 250 may reduce and/or eliminate the pause before performing a neighbor cell measurement, as described in more detail elsewhere herein. As shown, because UE 250 has reduced and/or eliminated the pause (e.g., an amount of time to wait before performing a neighbor cell measurement) , UE 250 increases the likelihood that UE 250 will recognize one or more eNBs 210 as neighbor eNBs 210b-e. Thus, as shown, UE 250 is more likely to remain connected to dedicated RAN 105, thereby increasing performance of UE 250 when travelling at a high rate of speed. This and other techniques for increasing the likelihood that UE 250 remains connected to dedicated RAN 105 when UE 250 is travelling at a high rate of speed are described in more detail elsewhere herein.

Fig. 8 is a diagram illustrating an example process 800 performed, for example, by a user equipment, in accordance with various aspects of the present disclosure. In some aspects, one or more process blocks of Fig. 8 may be performed by UE 250.

As shown in Fig. 8, process 800 may include determining a speed of a user equipment (UE) (block 810) . For example, UE 250 may determine a rate of speed at which UE 250 is moving. In some aspects, UE 250 may determine the speed of UE 250 using global positioning system (GPS) measurements. Additionally, or alternatively, UE 250 may determine the speed based on a Doppler frequency (e.g., a measured and filtered Doppler frequency) . Additionally, or alternatively, UE 250 may determine the speed based on a quantity of times UE 250 reselects a cell (e.g., is handed over from a serving eNB 210 to a neighbor eNB 210) within a time period. Additionally, or alternatively, UE 250 may determine the speed using another technique.

As shown in Fig. 8, process 800 may include determining, based on the speed, an amount of time to wait before measuring a parameter of a communication with a neighbor base station (block 820) . For example, UE 250 may determine an amount of time to wait (e.g., to pause) before performing a neighbor cell measurement of neighbor eNB 210. In some aspects, UE 250 may determine to pause before performing a neighbor cell measurement after performing one or more preceding neighbor cell measurements. For example, UE 250 may determine that a threshold quantity of preceding neighbor cell measurements (e.g., three consecutive neighbor cell measurements) satisfied a condition, such as a measured parameter (e.g., a power parameter, a quality parameter, etc. ) failing to satisfy a threshold. Based on this determination, UE 250 may determine to pause before performing one or more additional neighbor cell measurements.

UE 250 may determine a pause time (e.g., an amount of time to wait) based on the speed of UE 250. For example, UE 250 may adjust the pause time when the speed satisfies a threshold (e.g., greater than 150 kph, greater than 200 kph, greater than 250 kph, greater than 300 kph, etc. ) . As the speed of UE 250 increases (e.g., satisfies a first threshold, satisfies a second threshold that is greater than the first threshold, etc. ) , UE 250 may decrease the pause time.

In some aspects, UE 250 may decrease the pause time by an amount of time (e.g., a predetermined, preconfigured, or computed amount of time) based on the speed and/or the satisfied threshold. In some aspects, the amount of time may be the same amount for different thresholds. In some aspects, the amount of time may be different for different thresholds. Additionally, or alternatively, UE 250 may calculate the pause time using a formula that incorporates the speed. In some aspects, UE 250 may calculate the pause time such that the pause time is inversely proportional to the speed (e.g., as the speed increases, the pause time decreases) . In some aspects, UE 250 may set the pause time to zero (e.g., may not wait before performing an additional neighbor cell measurement) . In this way, UE 250 is more likely to recognize neighbor eNBs 210 (e.g., an eNB 210 identified as a neighbor eNB by a UE’s serving eNB) when moving at a high speed, thereby increasing the likelihood that UE 250 remains connected to dedicated RAN 105.

In some aspects, UE 250 may store information that identifies a default amount of time to wait before performing the neighbor cell measurement. In this case, UE 250 may reduce the default amount of time, based on the speed, to determine an updated pause time. UE 250 may store the updated pause time, and may adjust the pause time as the speed of UE 250 changes.

In some aspects, UE 250 may measure a serving cell parameter (e.g., a power parameter, a quality parameter, etc. ) associated with serving eNB 210 that provides service to UE 250 (e.g., to access dedicated RAN 105) . In some cases, such as when UE 250 is not travelling at a high rate of speed, UE 250 may determine not to perform a neighbor cell measurement based on the serving cell parameter. For example, when the serving cell parameter satisfies a threshold, indicating that communications with serving eNB 210 are high power and/or high quality, UE 250 may determine not to perform the neighbor cell measurement. Additionally, or alternatively, UE 250 may determine, based on the serving cell parameter, to increase an amount of time that UE 250 waits before performing a neighbor cell measurement. However, when UE 250 is travelling at a high rate of speed, in aspects, UE 250 may determine to perform the neighbor cell measurement regardless of the serving cell parameter (e.g., regardless of whether the serving cell parameter satisfies a threshold) . In this way, UE 250 is more likely to recognize neighbor eNBs 210b-e when moving at a high speed, thereby increasing the likelihood that UE 250 remains connected to dedicated RAN 105.

Additionally, or alternatively, UE 250 may store information that identifies a default time adjustment to the pause time based on the serving cell parameter. When UE 250 is travelling at a high speed (e.g., greater than or equal to a threshold) , UE 250 may modify the default time adjustment. For example, assume that UE 250 normally (e.g., by default and/or when UE 250 is not travelling at a high speed) increases a pause time by ten seconds when a serving cell parameter satisfies a threshold. In this case, when UE 250 is travelling at a high speed, UE 250 may increase the pause time by five seconds (e.g., a smaller amount of time) when the serving cell parameter satisfies the same threshold. As another example, UE 250 may determine not to increase the pause time when the serving cell parameter satisfies the same threshold. In other words, UE 250 may reduce the time increase to the pause timer, when the serving cell parameter satisfies a threshold, when UE 250 is travelling at a high speed.

As shown in Fig. 8, in some aspects, process 800 may optionally include determining one or more components of the UE to be used to measure the parameter (block 830) . For example, UE 250 may determine one or more components, of UE 250, to be used to perform the neighbor cell measurement. In some aspects, the component (s) of UE 250 may correspond to one or more components described herein in connection with Fig. 6. In some aspects, UE 250 may perform neighbor cell measurements based on a discontinuous reception (DRX) cycle. Using a DRX cycle, UE 250 may set one or more components to an idle mode (e.g., a low power state, such as deactivated, powered down, in sleep mode, in standby mode, etc. ) for a time period. After the time period has elapsed, UE 250 may set the component (s) to a connected mode (e.g., a high power state, such as activated, powered on, in operational mode, etc. ) to communicate with eNBs 210. After communicating with eNBs 210, UE 250 may set the component (s) back to the idle mode, and may repeat the DRX cycle.

When UE 250 is travelling at a high speed (e.g., greater than a threshold) , UE 250 may determine to set fewer components to connected mode than when UE 250 is travelling at a low speed (e.g., below a threshold) . For example, when UE 250 is travelling at a low speed, UE 250 may power on a receiver component, a communication measurement component, a paging/monitoring component, a system information collection component, a call processing component, a data processing component, or the like. When UE 250 is travelling at a high speed, however, UE 250 may power on only the receiver component and the communication measurement component. In other words, when travelling at a high speed, UE 250 may power on only components required to receive and/or measure a communication with neighbor eNB 210. In this way, UE 250 may conserve battery power. In some aspects, when UE 250 is travelling at a high speed, UE 250 may wake up during an off period of a DRX cycle to increase the likelihood that UE 250 remains connected to dedicated RAN 105. For example, when travelling at a high speed, UE 250 may wake up during an off period of a DRX cycle by powering on, for example, only components required to receive and/or measure a communication with neighbor eNB 210. In this way, UE 250 may conserve battery power.

Additionally, or alternatively, UE 250 may use two different DRX cycles when travelling at a high speed, with a first cycle being shorter than a second cycle. When the first cycle elapses, UE 250 may power on only components required to receive and measure the communication, and when the second cycle elapses, UE 250 may power on other components (and/or may also power on the components required to receive and measure the communication) . For example, every 1 second, UE 250 may power on a smaller quantity of components required to receive and measure the communication. As another example, every 3 seconds, UE 250 may power on a larger quantity of components. In this way, UE 250 may conserve battery power, and UE 250 is more likely to recognize neighbor eNBs 210 when moving at a high speed, due to receiving and measuring neighbor cell measurements more often, thereby increasing the likelihood that UE 250 remains connected to dedicated RAN 105.

As shown in Fig. 8, process 800 may include measuring the parameter using one or more components of the UE to be used to measure the parameter and/or after waiting the amount of time (block 840) . For example, UE 250 may measure the parameter of the communication with neighbor eNB 210b-e after waiting the amount of time. As described above, UE 250 may have reduced or eliminated the amount of time. In the case where UE 250 sets the amount of time to zero, waiting the amount of time (e.g., zero seconds) may mean that UE 250 performs a neighbor cell measurement without waiting any additional amount of time (e.g., using a default DRX cycle, such as every 1.28 seconds, every 2 seconds, etc., or waking up during an off duration of a DRX cycle to at least measure the parameter of the communication with neighbor eNB 210b-e) .

Additionally, or alternatively, UE 250 may measure the parameter using one or more components determined as described above. For example, UE 250 may power on only the component (s) required to measure the parameter, and may use those component (s) to measure the parameter. In this way, UE 250 may conserve power while also increasing the likelihood that UE 250 remains connected to dedicated RAN 105.

In some aspects, the amount of time is inversely proportional to the speed. In some aspects, determining the amount of time comprises setting the amount of time to zero based on the speed. In some aspects, the amount of time is associated with a pause timer that indicates a default amount of time to wait before measuring the parameter, and determining the amount of time comprises reducing the default amount of time to obtain the amount of time. In some aspects, process 800 further includes measuring a serving cell parameter associated with a communication with a serving base station and determining the amount of time regardless of the serving cell parameter. In some aspects, process 800 further includes measuring a serving cell parameter associated with a communication with a serving base station, and determining the amount of time comprises determining the amount of time based on the serving cell parameter. In some aspects, process 800 further includes determining, based on the speed, one or more components of the UE to be used to measure the parameter, and measuring the parameter comprises measuring the parameter using the one or more components.

In some aspects, process 800 further includes activating a component of the UE to measure the parameter, at least one other component of the UE being deactivated, and measuring the parameter comprises measuring the parameter using the component. In some aspects, process 800 further includes determining that a threshold quantity of neighbor cell measurements do not satisfy a threshold value, and determining the speed of the UE comprises determining the speed of the UE based on determining that the threshold quantity of neighbor cell measurements do not satisfy the threshold value. In some aspects, the neighbor base station uses at least one of a different frequency or a different radio access technology than a serving base station associated with the UE. In some aspects, process 800 further includes reporting the parameter to a serving base station for transitioning communication of the UE to the neighbor base station, and the neighbor base station and the serving base station are associated with a dedicated network associated with a cause of the speed of the UE.

In some aspects, the measured parameter may include, for example, a power parameter (e.g., RSRP, RSCP, etc. ) , a quality parameter (e.g., RSRQ, SINR, etc. ) , or the like, associated with a communication between UE 250 and neighbor eNB 210b-e. In some aspects, serving eNB 210 and neighbor eNB 210b-e may use a same RAT (e.g., LTE) and/or a same frequency (e.g., a frequency associated with dedicated RAN 105) to communicate with UE 250. Additionally, or alternatively, serving eNB 210 and neighbor eNB 210b-e may use a different RAT and/or a different frequency to communicate with UE 250. UE 250 may report the measured parameter to serving eNB 210 (and/or neighbor eNB 210b-e) , which may initiate a handoff or reselection of UE 250 from serving eNB 210 to neighbor eNB 210b-e based on the measured parameter (e.g., when the measured parameter satisfies a threshold) . In this way, UE 250 may increase a likelihood of a successful handoff or reselection from serving eNB 210 to neighbor eNB 210 (e.g., both of which may be associated with dedicated RAN 105) , thereby increasing a likelihood that UE 250 benefits from performance enhancements associated with dedicated RAN 105, and also increasing a likelihood that UE 250 stays connected to dedicated RAN 105.

Consequently, UE 250 may avoid being handed over to another RAN (e.g., public RAN 125) , different than dedicated RAN 105, and being unable to return to dedicated RAN 105 (e.g., due to network and/or UE configuration issues) . Additionally or alternatively, UE 250 may reduce and/or eliminate loading another RAN (e.g., public RAN 125) by remaining on dedicated RAN 105. For example, during a first time period, UE 250 may be served by eNB 210a, and eNB 210b may be identified as a neighbor eNB. As the train moves, during a second time period, UE 250 may be successfully handed off to neighbor eNB 210b such that UE 250 is served by eNB 210b, and eNB 210c may be identified as a neighbor eNB. Thereafter, as the train moves, during a third time period, UE 250 may be successfully handed off to neighbor eNB 210c such that UE 250 is served by eNB 210c, and eNB 210d may be identified as a neighbor eNB, and so on.

Although Fig. 8 shows example blocks of process 800, in some aspects, process 800 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 8. Additionally, or alternatively, two or more of the blocks of process 800 may be performed in parallel.

Fig. 9 is a diagram illustrating an example 900 of process 800 illustrated in Fig. 8. Fig. 9 shows an example of adjusting an amount of time to wait before performing a neighbor cell measurement based on a speed of UE 250.

As shown in Fig. 9, assume that UE 250 is located on a high-speed train, and is travelling at a high speed (e.g., greater than a threshold, such as 150 kph) . Assume that UEs 250 located on the high-speed train are served by dedicated RAN 105. Further, assume that UE 250 is served by serving eNB 210, and performs neighbor cell measurements of one or more neighbor eNBs 210. As shown, assume that three consecutive neighbor cell measurements include a parameter that falls below a threshold (e.g., a power threshold, a quality threshold, etc. ) .

Based on the low parameters in the three consecutive neighbor cell measurements, UE 250 may normally wait to perform another neighbor cell measurement, and may fail to stay connected to dedicated RAN 105 (e.g., as described above in connection with Fig. 7A) . However, as shown, assume that UE 250 measures a speed of UE 250 and determines that the speed of UE 250 satisfies a threshold (e.g., shown as 150 kph) . Based on the speed, UE 250 determines to pause for zero seconds (e.g., determines not to pause) before performing an additional neighbor cell measurement. As shown, UE 250 continues performing neighbor cell measurements without pausing (e.g., without pausing for an additional amount of time after a DRX cycle elapses) , and thus remains connected to dedicated RAN 105.

In this way, UE 250 may benefit from performance enhancements associated with dedicated RAN 105 when UE 250 is travelling at a high speed. Furthermore, UE 250 may conserve resources of public RAN 125 that would otherwise be used to communicate with the high-speed UE 250.

As indicated above, Fig. 9 is provided merely as an example. Other examples are possible and may differ from what was described with regard to Fig. 9.

Techniques described herein increase the likelihood that UE 250 remains connected to dedicated RAN 105 when UE 250 is travelling at a high rate of speed, thereby improving performance of dedicated RAN 105, UE 250, and public RAN 125.

The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practice of the aspects.

As used herein, the term component is intended to be broadly construed as hardware, firmware, or a combination of hardware and software.

Some aspects are described herein in connection with thresholds. As used herein, satisfying a threshold may refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, or the like.

It will be apparent that systems and/or methods, described herein, may be implemented in different forms of hardware, firmware, or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described herein without reference to specific software code—it being understood that software and hardware can be designed to implement the systems and/or methods based on the description herein.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of possible aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of possible aspects includes each dependent claim in combination with every other claim in the claim set. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover: a； b； c； a and b； a and c； b and c； and a, b and c.

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more. ” Furthermore, as used herein, the term “set” is intended to include one or more items, and may be used interchangeably with “one or more. ” Where only one item is intended, the term “one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.

Claims

A method for wireless communication， comprising：

determining， by a user equipment (UE) ， a speed of the UE；

determining， by the UE and based on the speed， an amount of time to wait before measuring a parameter of a communication with a neighbor base station； and

measuring， by the UE and after waiting the amount of time， the parameter of the communication with the neighbor base station.
The method of claim 1， wherein the amount of time is inversely proportional to the speed.
The method of claim 1， wherein determining the amount of time comprises：

setting the amount of time to zero based on the speed.
The method of claim 1， wherein the amount of time is associated with a pause timer that indicates a default amount of time to wait before measuring the parameter； and

wherein determining the amount of time comprises reducing the default amount of time to obtain the amount of time.
The method of claim 1， further comprising：

measuring a serving cell parameter associated with a communication with a serving base station； and

determining the amount of time regardless of the serving cell parameter.
The method of claim 1， further comprising：

measuring a serving cell parameter associated with a communication with a serving base station； and

wherein determining the amount of time comprises determining the amount of time based on the serving cell parameter.
The method of claim 1， further comprising：

determining， based on the speed， one or more components of the UE to be used to measure the parameter； and

wherein measuring the parameter comprises measuring the parameter using the one or more components.
The method of claim 1， further comprising：

activating a component of the UE to measure the parameter，

at least one other component of the UE being deactivated； and

wherein measuring the parameter comprises measuring the parameter using the component.
The method of claim 1， further comprising：

determining that a threshold quantity of neighbor cell measurements do not satisfy a threshold value； and

wherein determining the speed of the UE comprises determining the speed of the UE based on determining that the threshold quantity of neighbor cell measurements do not satisfy the threshold value.
The method of claim 1， wherein the neighbor base station uses at least one of a different frequency or a different radio access technology than a serving base station associated with the UE.
The method of claim 1， further comprising：

reporting the parameter to a serving base station for transitioning communication of the UE to the neighbor base station； and

wherein the neighbor base station and the serving base station are associated with a dedicated network associated with a cause of the speed of the UE.
A user equipment (UE) for wireless communication， comprising：

one or more processors configured to：

determine a speed of the UE；

determine， based on the speed， an amount of time to wait before measuring a parameter of a communication with a neighbor base station； and

measure the parameter of the communication with the neighbor base station after waiting the amount of time.
The UE of claim 12， wherein the amount of time is inversely proportional to the speed.
The UE of claim 12， wherein the one or more processors， when determining the amount of time， are further configured to：

set the amount of time to zero based on the speed.
The UE of claim 12， wherein the amount of time is associated with a pause timer that indicates a default amount of time to wait before measuring the parameter； and

wherein the one or more processors， when determining the amount of time， are further configured to reduce the default amount of time to obtain the amount of time.
The UE of claim 12， wherein the one or more processors are further configured to：

measure a serving cell parameter associated with a communication with a serving base station； and

determine the amount of time regardless of the serving cell parameter.
The UE of claim 12， wherein the one or more processors are further configured to：

determine， based on the speed， one or more components of the UE to be used to measure the parameter； and

wherein the one or more processors， when measuring the parameter， are further configured to measure the parameter using the one or more components.
The UE of claim 12， wherein the one or more processors are further configured to：

activate a component of the UE to measure the parameter，

at least one other component of the UE being deactivated； and

wherein the one or more processors， when measuring the parameter， are further configured to measure the parameter using the component.
The UE of claim 12， wherein the one or more processors are further configured to：

determine that a threshold quantity of neighbor cell measurements do not satisfy a threshold value； and

wherein the one or more processors， when determining the speed of the UE， are further to configured determine the speed of the UE based on determining that the threshold quantity of neighbor cell measurements do not satisfy the threshold value.
The UE of claim 11， wherein the one or more processors are further configured to：

report the parameter to a serving base station for a handoff to the neighbor base station； and

wherein the neighbor base station and the serving base station are associated with a dedicated network associated with a cause of the speed of the UE.
A non-transitory computer-readable medium storing instructions for wireless communication， the instructions comprising：

one or more instructions that， when executed by one or more processors of a user equipment (UE) ， cause the one or more processors to：

determine a speed of the UE；

determine， based on the speed， an amount of time to wait before measuring a parameter of a communication with a neighbor base station； and

measure the parameter of the communication with the neighbor base station after waiting the amount of time.
The non-transitory computer-readable medium of claim 21， wherein the amount of time is inversely proportional to the speed.
The non-transitory computer-readable medium of claim 21， wherein the one or more instructions， that cause the one or more processors to determine the amount of time， further cause the one or more processors to：

set the amount of time to zero based on the speed.
The non-transitory computer-readable medium of claim 21， wherein the amount of time is associated with a pause timer that indicates a default amount of time to wait before measuring the parameter； and

wherein the one or more instructions， that cause the one or more processors to determine the amount of time， further cause the one or more processors to reduce the default amount of time to obtain the amount of time.
The non-transitory computer-readable medium of claim 21， wherein the one or more instructions further cause the one or more processors to：

measure a serving cell parameter associated with a communication with a serving base station； and

determine the amount of time regardless of the serving cell parameter.
The non-transitory computer-readable medium of claim 21， wherein the one or more instructions further cause the one or more processors to：

determine， based on the speed， one or more components of the UE to be used to measure the parameter； and

wherein the one or more instructions， that cause the one or more processors to measure the parameter， further cause the one or more processors to measure the parameter using the one or more components.
The non-transitory computer-readable medium of claim 21， wherein the one or more instructions further cause the one or more processors to：

activate a component of the UE to measure the parameter，

at least one other component of the UE being deactivated； and

wherein the one or more instructions， that cause the one or more processors to measure the parameter， further cause the one or more processors to measure the parameter using the component.
The non-transitory computer-readable medium of claim 21， wherein the one or more instructions further cause the one or more processors to：

determine that a threshold quantity of neighbor cell measurements do not satisfy a threshold value； and

wherein the one or more instructions， that cause the one or more processors to determine the speed of the UE， further cause the one or more processors to determine the speed of the UE based on determining that the threshold quantity of neighbor cell measurements do not satisfy the threshold value.
The non-transitory computer-readable medium of claim 21， wherein the neighbor base station uses at least one of a different frequency or a different radio access technology than a serving base station associated with the UE.
A method， apparatus， system， computer program product， non-transitory computer-readable medium， and user equipment as substantially described herein with reference to and as illustrated by the accompanying drawings.