Channel estimation for multiple radio access technologies in high-speed scenarios

Abstract

Methods, systems, and devices for wireless communication are described. The described techniques provide a user equipment (UE) that uses information identified through a radio access technology (RAT) (e.g., Long Term Evolution (LTE)) to support communications over another RAT (e.g., New Radio (NR)). For example, the UE may receive a high-speed indication associated with the UE's first radio access with the first base station from a first base station operating according to a first radio access technology. The UE may perform a channel estimation procedure for the first radio access to generate a Doppler value based on receiving the indication. The UE may apply the generated Doppler value to a frequency tracking loop or a time tracking loop for communications with a second base station over a second radio access, wherein the second base station operates according to a second RAT.

Description

Technology Field

[0001] Technology field

[0002] The following relates to wireless communications including channel estimation for multiple radio access technologies in high-speed scenarios. Background Technology

[0003] background

[0004] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, and broadcast. These systems may be able to support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include 4th generation (4G) systems, such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and 5th generation (5G) systems, which may be referred to as New Radio (NR) systems. These systems may employ technologies such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal FDMA (OFDMA), or Discrete Fourier Transform-Spread-Orthogonal Frequency Division Multiplexing (DFT-S-OFDM). A wireless multiple access communication system may include one or more base stations or one or more network access nodes, each of which simultaneously supports communication to multiple communication devices, which may otherwise be known as user equipment (UE).

[0005] In some cases, a wireless communication device, such as a user equipment (UE) or a base station, may support communications through more than one multi-access system. For example, a UE may be configured to communicate through both LTE and NR procedures. In some cases, a UE may use LTE and NR simultaneously or concurrently.

[0006] summation

[0007] The described techniques relate to improved methods, systems, devices, and apparatus that support channel estimation for multiple radio access technologies in high-speed scenarios. Generally, the described techniques provide a user equipment (UE) that uses information identified via a radio access technology (RAT) (e.g., Long Term Evolution (LTE)) to support communications over different RATs (e.g., New Radio (NR)). For example, the UE may receive a high-speed indication associated with the UE's first radio access with the first base station from a first base station operating according to a first radio access technology. The high-speed indication may be transmitted in system information such as System Information Block Type 2 (SIB2). The UE may perform a channel estimation procedure for the first radio access to generate Doppler values ​​based on receiving the indication. The UE may apply a Doppler value generated in a frequency tracking loop or a time tracking loop for communications with a second base station through a second wireless access, wherein the second base station is operating according to the second RAT.

[0008] A method for wireless communication in user equipment (UE) is described. The method may include receiving a high-speed indication associated with a first wireless connection of the UE with the first base station from a first base station operating according to a first radio access technique; performing a channel estimation procedure for the first wireless connection to generate a Doppler value based on receiving the high-speed indication; and communicating with a second base station operating according to a second radio access technique based on applying the generated Doppler value to a frequency tracking loop or time tracking loop for a second wireless connection of the UE with the second base station.

[0009] An apparatus for wireless communication in a UE is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive a high-speed indication associated with a first wireless connection of the UE with the first base station from a first base station operating according to a first radio access technique, to perform a channel estimation procedure for the first wireless connection to generate a Doppler value based on receiving the high-speed indication, and to communicate with a second base station operating according to a second radio access technique based on applying the generated Doppler value to a frequency tracking loop or time tracking loop for a second wireless connection of the UE with the second base station.

[0010] Another device for wireless communication in a UE is described. The device may include means for receiving a high-speed indication associated with a first wireless connection of a UE with a first base station from a first base station operating according to a first wireless access technology, means for performing a channel estimation procedure for the first wireless connection to generate a Doppler value based on receiving the high-speed indication, and means for communicating with a second base station operating according to a second wireless access technology based on applying the generated Doppler value to a frequency tracking loop or time tracking loop for a second wireless connection of a UE with a second base station.

[0011] A non-transient computer-readable medium for storing code for wireless communication in a UE is described. The code may include instructions executable by a processor to communicate with a second base station operating according to a second wireless access technology based on receiving a high-speed indication associated with a first wireless connection of the UE with the first base station from a first base station operating according to a first wireless access technology, performing a channel estimation procedure for the first wireless connection to generate a Doppler value based on receiving the high-speed indication, and applying the generated Doppler value to a frequency tracking loop or time tracking loop for a second wireless connection of the UE with the second base station.

[0012] Some examples of the methods, apparatuses, and non-transient computer-readable media described herein may further include operations, features, means, or commands for receiving a command to perform a handover procedure to a second base station, and, based on receiving the command, generating a random access preamble for a handover procedure to a second base station using a Doppler value generated using a channel estimation procedure with a first base station, and communicating with the second base station includes transmitting the random access preamble generated in response to the received command to the second base station.

[0013] In some examples of the methods, apparatuses, and non-transient computer-readable media described herein, the Doppler value comprises a first Doppler value, and the methods, apparatuses, and non-transient computer-readable media may perform a second channel estimation procedure to generate a second Doppler value associated with communications with a second base station operating using a second radio access technique, and may include additional operations, features, means, or instructions for applying the second Doppler value to communications with a first base station using a first radio access technique.

[0014] In some examples of the methods, apparatuses, and non-transient computer-readable media described herein, applying a second Doppler value may include operations, features, means, or commands for adjusting a frequency tracking loop or a time tracking loop for a first radio connection with a first base station operating according to a first radio access technology.

[0015] Some examples of the methods, devices, and non-transient computer-readable media described herein may further include operations, features, means, or instructions for determining that the difference between a second Doppler value and a first Doppler value may be greater than or equal to a Doppler threshold, and for performing a new channel estimation procedure for a first wireless access to generate a new Doppler value based on determining that the difference may be greater than or equal to a Doppler threshold.

[0016] Some examples of the methods, apparatuses, and non-transient computer-readable media described herein may further include operations, features, means, or instructions for monitoring decoding performance metrics associated with downlink communications via a first radio access technology and downlink communications via a second radio access technology, and for a time tracking loop, a frequency tracking loop, or coordinating the first radio access technology, the second radio access technology, or both thereof based on monitoring the decoding performance metrics.

[0017] Some examples of the methods, apparatuses, and non-transient computer-readable media described herein may further include operations, features, means, or instructions for determining the relationship between a first base station associated with a first radio access technology and a second base station associated with a second radio access technology by monitoring a first Doppler metric associated with a first radio access technology and a second Doppler metric associated with a second radio access technology during a monitoring period, based on receiving an indication.

[0018] Some examples of the methods, devices, and non-transient computer-readable media described herein may further include operations, features, means, or instructions for applying an adjusted Doppler value to adjust a frequency tracking loop or a time tracking loop for a second wireless access based on the generated Doppler value.

[0019] Some examples of the methods, devices, and non-transient computer-readable media described herein may further include operations, features, means, or instructions for determining a Doppler value adjusted based on a scaling factor associated with a second radio frequency spectrum band corresponding to a second radio access technology.

[0020] Some examples of the methods, devices, and non-transient computer-readable media described herein may further include operations, features, means, or instructions for applying a scaling factor when the difference between a first radio frequency spectrum band and a second radio frequency spectrum band associated with a first radio access technology may be greater than a frequency threshold.

[0021] In some examples of the methods, devices, and non-transient computer-readable media described herein, receiving a mark may include operations, features, means, or commands for receiving system information including a high-speed mark from a first base station.

[0022] In some examples of the methods, apparatuses, and non-transient computer-readable media described herein, system information may be a system information block type 2 (SIB2), and a high-speed indication may be a high-speed flag in a system information block (SIB).

[0023] In some examples of the methods, apparatuses, and non-transient computer-readable media described herein, the first radio access technology operates in a first radio frequency spectrum band, and the second radio access technology operates in a second radio frequency spectrum band. Brief explanation of the drawing

[0024] A brief explanation of the drawings FIG. 1 illustrates an example of a wireless communication system that supports channel estimation for a number of radio access technologies in a high-speed scenario, according to embodiments of the present disclosure. FIG. 2 illustrates an example of a wireless communication system that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. FIG. 3 illustrates an example of a process flow that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. FIGS. 4 and 5 illustrate block diagrams of devices that support channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. FIG. 6 illustrates a block diagram of a communication manager that supports channel estimation for a number of radio access technologies in a high-speed scenario, according to embodiments of the present disclosure. FIG. 7 illustrates a diagram of a system including a device that supports channel estimation for a number of radio access technologies in a high-speed scenario, according to embodiments of the present disclosure. FIGS. 8 through 11 illustrate flowcharts illustrating methods for supporting channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. Specific details for implementing the invention

[0025] details

[0026] User Equipment (UE) devices may operate in high-mobility environments, such as trains and vehicles. In New Radio (NR) systems, base stations may be densely distributed in these environments to support communication at high frequencies (e.g., millimeter wave (mmW) frequencies). When UEs are operating in high-mobility environments, they may experience significant Doppler shifting in communications between the UEs and base stations. This Doppler shifting can be particularly problematic when communicating at high frequencies. For example, in high-band NR systems, a UE may need to estimate when it is operating in a high-mobility scenario using channel estimation procedures that may consume significant processing resources.

[0027] Aspects of the present disclosure describe techniques for a UE to leverage information determined by communications over a first radio access technology (RAT) (e.g., Long Term Evolution (LTE)) for communications over a second RAT (e.g., NR). For example, an LTE base station may transmit to the UE a set of system information (e.g., in a System Information Block (SIB) message) that includes a flag (e.g., a high-speed flag in SIB2) indicating that the UE is operating in a high-mobility scenario. Upon identifying a high-mobility flag for LTE, the UE may enable an operating mode that allows the UE to apply Doppler information (e.g., Doppler values) generated using a channel estimation procedure over the first communication link (LTE) to the second communication link (NR). For example, the UE may apply Doppler values ​​to the time tracking loop (TTL) or frequency tracking loop (FTL) of the radio frequency chain (e.g., RF circuitry) corresponding to the NR communications. In some cases, Doppler shift values ​​may not be appropriate for the second communication link (e.g., due to differences in frequency bands). To address this, in some examples, the UE may apply a scaling factor to the Doppler shift values ​​before applying them to the second communication link. The scaling factor may be based on channel conditions, predefined by the UE, signaled by the base station, or similar. The application of Doppler values ​​determined using LTE versus NR communications may support improved channel estimation or capture. More specifically, channel estimation in high-band NR may entail significant process overhead compared to LTE channel estimation.In this way, rather than performing channel estimation in both RATs, the UE may use channel estimation information (e.g., Doppler values) from the first RAT for communications in the second RAT.

[0028] Additionally or alternatively, information identified for one RAT may be used to determine communication efficiency in another RAT. That is, the UE may use information from one RAT to cross-check communications in another RAT. For example, the UE may compare decoding performance, Doppler metrics, etc., for both RATs to determine whether communications in one or both RATs need to be coordinated. In some examples, coordinating communications may involve applying the outputs of the FTL or TTL in one RAT to the FTL or TTL in another RAT. These and other techniques are further described in conjunction with the drawings.

[0029] Aspects of the present disclosure are first described in the context of wireless communication systems. Aspects of the present disclosure are further described in process flow diagrams for a UE operating in a high-speed scenario. Aspects of the present disclosure are further illustrated and described by reference to device diagrams, system diagrams, and flowcharts relating to channel estimation for a number of radio access technologies in a high-speed scenario.

[0030] FIG. 1 illustrates an example of a wireless communication system (100) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. The wireless communication system (100) may include one or more base stations (105), one or more UEs (115), and a core network (130). In some examples, the wireless communication system (100) may be an LTE network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or an NR network. In some examples, the wireless communication system (100) may support enhanced broadband communication, ultra-high reliability (e.g., mission-critical) communication, low-latency communication, communication with low-cost and low-complexity devices, or any combination thereof.

[0031] Base stations (105) may be scattered across a geographical area to form a wireless communication system (100) and may be devices of different forms or different capabilities. Base stations (105) and UEs (115) may communicate wirelessly through one or more communication links (125). Each base station (105) may provide a coverage area (110) in which UEs (115) and base stations (105) may establish one or more communication links (125). The coverage area (110) may be an example of a geographical area in which base stations (105) and UEs (115) may support the communication of signals according to one or more radio access technologies.

[0032] UEs (115) may be scattered throughout the coverage area (110) of the wireless communication system (100), and each UE (115) may be stationary, mobile, or both at different times. UEs (115) may be devices having different forms or different capabilities. Some examples of UEs (115) are illustrated in FIG. 1. The UEs (115) described herein may be able to communicate with various types of devices, such as other UEs (115), base stations (105), or network equipment (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network equipment), as illustrated in FIG. 1.

[0033] Base stations (105) may communicate with the core network (130), with each other, or with both. For example, base stations (105) may interface with the core network (130) through one or more backhaul links (120) (e.g., through S1, N2, N3, or other interfaces). Base stations (105) may communicate with each other over the backhaul links (120) (e.g., through X2, Xn, or other interfaces) directly (e.g., directly between base stations (105)) or indirectly (e.g., through the core network (130)) or both indirectly and directly. In some examples, the backhaul links (120) may be one or more wireless links or may include them.

[0034] One or more of the base stations (105) described in this specification may include a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB or a gigabit NodeB (any of these may be referred to as a gNB), a home NodeB, a home eNodeB, or other suitable terms, or may be referred to as such by those skilled in the art.

[0035] The UE (115) may include or be referred to as a mobile device, wireless device, remote device, handheld device, or subscriber device, or some other suitable term, wherein “device” may also be referred to as a unit, station, terminal, or client, among other examples. The UE (115) may also include or be referred to as a personal electronic device such as a cellular phone, personal digital assistant (PDA), tablet computer, laptop computer, or personal computer. In some examples, the UE (115) may include or be referred to as a wireless local loop (WLL) station, Internet of Things (IoT) device, Internet of Everything (IoE) device, or machine type communication (MTC) device, among other examples, which may be implemented in various objects such as appliances, or vehicles, meters, among other examples.

[0036] The UEs (115) described in this specification may be able to communicate with various types of devices, such as network equipment and base stations (105) including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, as shown in FIG. 1, among other embodiments, as well as other UEs (115) that may sometimes operate as relays.

[0037] UEs (115) and base stations (105) may communicate wirelessly with each other over one or more communication links (125) on one or more carriers. The term "carrier" may refer to a set of radio frequency spectrum resources having a defined physical layer structure to support the communication links (125). For example, a carrier used for a communication link (125) may include a portion of a radio frequency spectrum band (e.g., a bandwidth portion (BWP)) that operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquired signaling (e.g., synchronization signals, system information), control signaling that coordinates the operation for the carrier, user data, or other signaling. A wireless communication system (100) may support communication with the UE (115) using carrier aggregation or multi-carrier operation. The UE (115) may be composed of multiple downlink component carriers and one or more uplink component carriers depending on the carrier aggregation configuration. Carrier aggregation may be used with both frequency division duplexing (FDD) and time division duplexing (TDD) component carriers.

[0038] In some examples (e.g., in a carrier aggregation configuration), the carrier may also have control signaling or capture signaling that coordinates operations for other carriers. The carrier may be associated with a frequency channel (e.g., an Advanced Universal Mobile Telecommunications System Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN)) and may be positioned according to a channel raster for discovery by UEs (115). The carrier may operate in a standalone mode where initial capture and access may be performed through the carrier by UEs (115), or the carrier may operate in a non-standalone mode where access is anchored using a different carrier (e.g., of the same or different radio access technology).

[0039] The communication links (125) illustrated in the wireless communication system (100) may include uplink transmissions from the UE (115) to the base station (105), or downlink transmissions from the base station (105) to the UE (115). The carriers may carry downlink or uplink communications (e.g., in FDD mode), or may be configured to carry downlink and uplink communications (e.g., in TDD mode).

[0040] A carrier may be associated with a specific bandwidth of the radio frequency spectrum, and in some examples, the carrier bandwidth may be referred to as the "system bandwidth" of the carrier or the wireless communication system (100). For example, the carrier bandwidth may be one of a number of determined bandwidths (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz)) for carriers of a specific radio access technology. Devices of the wireless communication system (100) (e.g., base stations (105), UEs (115), or both) may have hardware configurations that support communication over a specific carrier bandwidth, or may be configurable to support communication over one of the sets of carrier bandwidths. In some examples, the wireless communication system (100) may include base stations (105) or UEs (115) that support simultaneous communication over carriers associated with multiple carrier bandwidths. In some examples, each served UE (115) may be configured to operate on parts of the carrier bandwidth (e.g., sub-band, BWP) or the entirety.

[0041] Signal waveforms transmitted over a carrier may consist of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM). In systems employing MCM techniques, a resource element may consist of one symbol period (e.g., the duration of one modulation symbol) and one subcarrier, wherein the symbol period and the subcarrier interval are inversely proportional. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both). Thus, the more resource elements the UE (115) receives and the higher the order of the modulation scheme, the higher the data rate may be for the UE (115). Wireless communication resources may refer to a combination of radio frequency spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial layers may further increase the data rate or data integrity for communication with the UE (115).

[0042] One or more numerologies for the carrier may be supported, where, the numerology is the subcarrier interval ( It may include ) and cyclic prefixes. The carrier may be divided into one or more BWPs having the same or different numerologies. In some examples, the UE (115) may be composed of multiple BWPs. In some examples, a single BWP for the carrier may be active at a given time, and communication to the UE (115) may be limited to one or more active BWPs.

[0043] Time intervals for base stations (105) or UEs (115) are, for example, It may also be expressed as a multiple of a basic time unit that may refer to a sampling period of seconds, where may also indicate the maximum supported subcarrier interval, and may also represent the maximum supported Discrete Fourier Transform (DFT) size. The time intervals of the communication resources may be organized according to radio frames, each having a specified duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0044] Each frame may contain multiple consecutively numbered subframes or slots, and each subframe or slot may have the same duration. In some examples, a frame may be divided into subframes (e.g., in the time domain), and each subframe may be further divided into multiple slots. Alternatively, each frame may contain a variable number of slots, and the number of slots may depend on the subcarrier interval. Each slot may contain multiple symbol periods (e.g., depending on the length of the cyclic prefix pre-defending each symbol period). In some wireless communication systems (100), a slot may be further divided into multiple mini-slots containing one or more symbols. Excluding the cyclic prefix, each symbol period may contain one or more (e.g., It may include sampling periods of ). The duration of the symbol period may depend on the subcarrier interval or frequency band of the operation.

[0045] A subframe, slot, mini-slot, or symbol may be the minimum scheduling unit of the wireless communication system (100) (e.g., in the time domain) and may be referred to as a transmission time interval (TTI). In some examples, the TTI duration (e.g., the number of symbol periods in the TTI) may be variable. Additionally or alternatively, the minimum scheduling unit of the wireless communication system (100) may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs).

[0046] Physical channels may be multiplexed on a carrier according to various techniques. Physical control channels and physical data channels may be multiplexed on a downlink carrier using, for example, one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A control domain for a physical control channel (e.g., a control resource set (CORESET)) may be defined by a number of symbol periods and may extend over a system bandwidth or a subset of the carrier's system bandwidth. One or more control domains (e.g., CORESETs) may be configured for a set of UEs (115). For example, one or more of the UEs (115) may monitor or search for a control domain for control information according to one or more search space sets, and each search space set may include one or more control channel candidates in one or more aggregation levels arranged in a cascade manner. The aggregation level for control channel candidates may mean the number of control channel resources (e.g., control channel elements (CCEs)) associated with encoded information for a control information format having a given payload size. The search space sets may include common search space sets configured to transmit control information to a plurality of UEs (115) and UE-specific search space sets for transmitting control information to a specific UE (115).

[0047] Each base station (105) may provide communication coverage through one or more cells, e.g., macro cells, small cells, hot spots, or other types of cells, or any combination thereof. The term “cell” may refer to a logical communication entity used for communication with the base station (105) (e.g., via a carrier) and may be associated with an identifier to distinguish neighboring cells (e.g., physical cell identifier (PCID), virtual cell identifier (VCID), etc.). In some examples, a cell may also refer to a geographic coverage area (110) or a part (e.g., a sector) of the geographic coverage area (110) where the logical communication entity operates. Such cells may range from smaller areas (e.g., structures, subsets of structures) to larger areas depending on various factors such as the capabilities of the base station (105). For example, the cell may be or include external spaces that are between or overlap with buildings, a subset of buildings, or geographical coverage areas (110) among other examples.

[0048] Macro cells generally cover a relatively large geographical area (e.g., a radius of several kilometers) and may allow unrestricted access by UEs (115) having service subscriptions to a network provider that supports the macro cells. Small cells may be associated with a low-power base station (105) compared to macro cells, and small cells may operate in frequency bands that are the same or different (e.g., licensed, unlicensed) as the macro cells. Small cells may provide unrestricted access to UEs (115) having service subscriptions to a network provider, or may provide restricted access to UEs (115) associated with small cells (e.g., UEs (115) in a closed subscriber group (CSG), UEs (115) associated with users in a home or office). The base station (105) may support one or multiple cells and may also support communication over one or more cells using one or multiple component carriers.

[0049] In some examples, the carrier may support multiple cells, and the different cells may be configured according to different protocol types (e.g., MTC, Narrowband IoT (NB-IoT), Enhanced Mobile Broadband (eMBB)) that may provide access to different types of devices.

[0050] In some examples, the base station (105) is mobile and thus may provide communication coverage for a moving geographical coverage area (110). In some examples, different geographical coverage areas (110) associated with different technologies may overlap, but different geographical coverage areas (110) may be supported by the same base station (105). In other examples, overlapping geographical coverage areas (110) associated with different technologies may be supported by different base stations (105). The wireless communication system (100) may include a heterogeneous network in which base stations (105) of different types provide coverage for various geographical coverage areas (110) using the same or different radio access technologies.

[0051] A wireless communication system (100) may support synchronous or asynchronous operation. For synchronous operation, base stations (105) may have similar frame timings, and transmissions from different base stations (105) may be roughly time-aligned. For asynchronous operation, base stations (105) may have different frame timings, and transmissions from different base stations (105) may not be time-aligned in some examples. The techniques described herein may be used for either synchronous or asynchronous operation.

[0052] Some UEs (115), such as MTCs or IoT devices, may be low-cost or low-complexity devices and may provide automated communication between machines (e.g., via machine-to-machine (M2M) communication). M2M communication or MTC may refer to data communication technologies that allow devices to communicate with each other or with a base station (105) without human intervention. In some examples, M2M communication or MTC may include communication from devices that incorporate sensors or meters for measuring or capturing information and relay such information to a central server or application program, which then uses the information or presents the information to humans interacting with the application program. Some UEs (115) may be designed to collect information or enable automated behavior of machines or other devices. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geological event monitoring, vehicle management and tracking, remote security sensing, physical access control, and transaction-based business charging.

[0053] Some UEs (115) may be configured to adopt operating modes that reduce power consumption, such as half-duplex communication (e.g., a mode that supports unidirectional communication through transmission or reception, but does not support simultaneous transmission and reception). In some examples, half-duplex communication may be performed at a reduced peak rate. Other power conservation techniques for UEs (115) include entering a power-saving "deep sleep" mode when not participating in active communication, operating on a limited bandwidth (e.g., depending on narrowband communications), or a combination of these techniques. For example, some UEs (115) may be configured for operation using a narrowband protocol type associated with a predefined portion or range (e.g., a set of subcarriers or sets of resource blocks (RBs)) within the carrier, within the carrier's guard band, or outside the carrier.

[0054] The wireless communication system (100) may be configured to support ultra-reliable communication or low-latency communication, or various combinations thereof. For example, the wireless communication system (100) may be configured to support ultra-reliable low-latency communication (URLLC) or mission-critical communication. UEs (115) may be designed to support ultra-reliable, low-latency, or critical functions (e.g., mission-critical functions). Ultra-reliable communication may include private communication or group communication and may be supported by one or more mission-critical services, such as mission-critical push-to-talk (MCPTT), mission-critical video (MCVideo), or mission-critical data (MCData). Support for mission-critical functions may include the prioritization of services, and mission-critical services may be used for public safety or general commercial applications. The terms ultra-high reliability, low latency, mission critical, and ultra-high reliability low latency may be used interchangeably in this specification.

[0055] In some examples, a UE (115) may also be able to communicate directly with other UEs (115) via a device-to-device (D2D) communication link (135) (e.g., using a peer-to-peer (P2P) or D2D protocol). One or more UEs (115) utilizing D2D communication may be within the geographical coverage area (110) of a base station (105). Other UEs (115) in such a group may be outside the geographical coverage area (110) of the base station (105) or otherwise may not be able to receive transmissions from the base station (105). In some examples, a group of UEs (115) communicating via D2D communication may utilize a one-to-many (1:M) system in which each UE (115) transmits to all other UEs (115) in the group. In some examples, the base station (105) facilitates the scheduling of resources for D2D communication. In other cases, D2D communication is performed between UEs (115) without the involvement of the base station (105).

[0056] In some systems, the D2D communication link (135) may be an example of a communication channel such as a sidelink communication channel between vehicles (e.g., UEs (115)). In some examples, vehicles may communicate using V2X (vehicle-to-everything) communication, V2V (vehicle-to-vehicle) communication, or some combination thereof. Vehicles may signal information related to traffic conditions, signal scheduling, weather, safety, urgency, or any other information related to the V2X system. In some examples, vehicles in the V2X system may communicate with road-side infrastructure, such as road-side units, or with a network, or both, through one or more network nodes (e.g., base stations (105)) using V2N (vehicle-to-network) communication.

[0057] The core network (130) may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network (130) may be an advanced packet core (EPC) or a 5G core (5GC), and may include at least one control plane entity that manages access and mobility (e.g., Mobility Management Entity (MME), Access and Mobility Management Functional Unit (AMF)) and at least one user plane entity that interconnects to external networks or routes packets (e.g., Serving Gateway (S-GW), Packet Data Network (PDN) Gateway (P-GW), or User Plane Functional Unit (UPF)). The control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management for UEs (115) served by base stations (105) associated with the core network (130). User IP packets may be transmitted through a user plane entity that may provide other functions as well as IP address allocation. The user plane entity may be connected to IP services (150) for one or more network operators. The IP services (150) may include access to the Internet, intranet(s), IP multimedia subsystem (IMS), or packet switching streaming services.

[0058] Some of the network devices, such as base stations (105), may include subcomponents, such as access network entities (140), which may be examples of access node controllers (ANCs). Each access network entity (140) may communicate with UEs (115) through one or more other access network transmitting entities (145), which may be referred to as radio heads, smart radio heads, or transmitting / receiving points (TRPs). Each access network transmitting entity (145) may include one or more antenna panels. In some configurations, various functions of each access network entity (140) or base station (105) may be distributed across various network devices (e.g., radio heads and ANCs) or integrated into a single network device (e.g., base station (105)).

[0059] A wireless communication system (100) may operate using one or more frequency bands, typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Generally, the range from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range in length from approximately 1 decimeter to 1 meter. UHF waves may be blocked or redirected due to buildings and surrounding features, but these waves may also pass through structures sufficiently for macrocells to provide service to UEs (115) located indoors. Transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to transmission using smaller frequencies and longer waves in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0060] The wireless communication system (100) may also operate in the super high frequency (SHF) region using a frequency band of 3 GHz to 30 GHz (also known as the centimeter band), or in the ultra high frequency (EHF) region of the spectrum (e.g., 30 GHz to 300 GHz) (also known as the millimeter band). In some examples, the wireless communication system (100) may support millimeter wave (mmW) communications between UEs (115) and base stations (105), and the EHF antennas of individual devices may be smaller or more closely spaced than UHF antennas. In some examples, this may facilitate the use of antenna arrays within the device. However, the propagation of EHF transmissions may undergo much greater atmospheric attenuation and a shorter range than SHF or UHF transmissions. The techniques disclosed herein may be employed across transmissions using one or more different frequency ranges, and the designated use of bands across these frequency ranges may vary depending on the country or regulatory body.

[0061] A wireless communication system (100) may utilize both licensed and unlicensed radio frequency spectrum bands. For example, a wireless communication system (100) may employ Licensed Assisted Access (LAA), LTE Unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band, such as the 5 GHz Industrial Scientific and Medical (ISM) band. When operating in an unlicensed radio frequency spectrum band, devices such as base stations (105) and UEs (115) may employ carriers for detecting collision detection and avoidance. In some examples, operations in unlicensed bands (e.g., LAA) may be based on carrier aggregation configurations with component carriers operating in a licensed band. Operations in the unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.

[0062] A base station (105) or UE (115) may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of the base station (105) or UE (115) may be located within one or more antenna arrays or antenna panels that may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be placed in an antenna assembly such as an antenna tower. In some examples, the antennas or antenna arrays associated with the base station (105) may be located at various geographical locations. The base station (105) may have an antenna array having multiple rows and columns of antenna ports that the base station (105) may use to support beamforming of communication with the UE (115). Likewise, the UE (115) may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support radio frequency beamforming for signals transmitted through the antenna ports.

[0063] Base stations (105) or UEs (115) may use MIMO communications to increase spectral efficiency and utilize multipath signal propagation by transmitting or receiving multiple signals through different spatial layers. Such techniques may be referred to as spatial multiplexing. Multiple signals may be transmitted by a transmitting device, for example, through different antennas or different combinations of antennas. Likewise, multiple signals may be received by a receiving device through different antennas or different combinations of antennas. Each of the multiple signals may be referred to as a separate spatial stream and may carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords). Different spatial layers may be associated with different antenna ports used for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO), where multiple spatial layers are transmitted to the same receiving device, and multi-user MIMO (MU-MIMO), where multiple spatial layers are transmitted to multiple devices.

[0064] Beamforming, which may also be referred to as spatial filtering, directional transmission, or directional reception, is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., base station (105), UE (115)) to shape or steer an antenna beam (e.g., transmit beam, receive beam) along a spatial path between a transmitting device and a receiving device. Beamforming may be achieved by combining signals communicated through antenna elements of an antenna array such that some signals propagating toward specific orientations experience constructive interference while others experience destructive interference. The adjustment of signals communicated through antenna elements may include the transmitting device or the receiving device applying amplitude offsets, phase offsets, or both to the signals carried through the antenna elements associated with the device. The adjustments associated with each of the antenna elements may be defined by a set of beamforming weights associated with a specific orientation (e.g., for the antenna array of the transmitting device or the receiving device or for some other orientation).

[0065] A base station (105) or a UE (115) may use beam sweeping techniques as part of beamforming operations. For example, the base station (105) may use multiple antennas or antenna arrays (e.g., antenna panels) to perform beamforming operations for directional communication with the UE (115). Some signals (e.g., synchronization signals, reference signals, beam select signals, or other control signals) may be transmitted multiple times in different directions by the base station (105). For example, the base station (105) may transmit signals according to different beamforming weight sets associated with different transmission directions. Transmitters to different beam directions may be used to identify the beam direction for later transmission or reception by the base station (105) (e.g., by a transmitting device such as the base station (105) or by a receiving device such as the UE (115).

[0066] Some signals, such as data signals associated with a specific receiving device, may be transmitted by the base station (105) in a single beam direction (e.g., a direction associated with a receiving device such as the UE (115)). In some examples, the beam direction associated with the transmissions along the single beam direction may be determined based on signals transmitted in one or more beam directions. For example, the UE (115) may receive one or more of the signals transmitted in different directions by the base station (105) and may report to the base station (105) an indication of the signal received by the UE (115) with the best signal quality or otherwise acceptable signal quality.

[0067] In some cases, transmission by a device (e.g., by a base station (105) or a UE (115)) may be performed using multiple beam directions, and the device may generate a combined beam for transmission (e.g., from a base station (105) to a UE (115)) using a combination of digital precoding or radio frequency beamforming. The UE (115) may report feedback indicating precoding weights for one or more beam directions, and the feedback may correspond to multiple beams configured across the system bandwidth or one or more sub-bands. The base station (105) may transmit a reference signal (e.g., a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS)) that may or may not be precoded. The UE (115) may provide feedback for beam selection, and this feedback may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., multi-panel type codebook, linear combination type codebook, port selection type codebook). Although these techniques are described with reference to signals transmitted in one or more directions by the base station (105), the UE (115) may employ similar techniques to transmit signals multiple times in different directions (e.g., to identify a beam direction for subsequent transmission or reception by the UE (115)) or to transmit a signal in a single direction (e.g., to transmit data to a receiving device).

[0068] A receiving device (e.g., UE (115)) may attempt to receive configurations (e.g., directional listening) multiple times when receiving various signals from a base station (105), such as synchronization signals, reference signals, beam select signals, or other control signals. For example, the receiving device may attempt multiple receiving directions by receiving through different antenna subarrays, by processing signals received according to different antenna subarrays, by receiving according to different sets of receiving beamforming weights (e.g., different directional listening weights) applied to signals received from multiple antenna elements of an antenna array, or by processing signals received according to different sets of receiving beamforming weights applied to signals received from multiple antenna elements of an antenna array, any of which may be referred to as "listening" according to different receiving configurations or receiving directions. In some examples, the receiving device may use a single receiving configuration to receive along a single beam direction (e.g., when receiving a data signal). A single receiving configuration may be aligned to a beam direction determined based on listening according to different receiving configuration directions (e.g., a beam direction determined based on listening according to multiple beam directions to have the highest signal strength, highest signal-to-noise ratio (SNR), or otherwise acceptable signal quality).

[0069] The wireless communication system (100) may be a packet-based network operating according to a layered protocol stack. In the user plane, communications at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. The Radio Link Control (RLC) layer may communicate over logical channels by performing packet segmentation and reassembly. The Medium Access Control (MAC) layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer may also improve link efficiency by using error detection techniques, error correction techniques, or both to support retransmissions at the MAC layer. In the control plane, the Radio Resource Control (RRC) protocol layer may provide the establishment, configuration, and maintenance of RRC connections between the core network (130) or base station (105) supporting radio bearers for user plane data and the UE (115). In the physical layer, transport channels may be mapped to physical channels.

[0070] UEs (115) and base stations (105) may support data retransmissions to increase the likelihood that data will be successfully received. Hybrid Auto Repeat Request (HARQ) feedback is a technique that increases the likelihood that data will be accurately received over a communication link (125). HARQ may include a combination of error detection (e.g., using Cyclic Redundancy Check (CRC)), Forward Error Correction (FEC), and retransmission (e.g., Auto Repeat Request (ARQ)). HARQ may improve throughput at the MAC layer under poor radio conditions (e.g., low signal-to-noise conditions). In some examples, the device may support same-slot HARQ feedback, where the device may provide HARQ feedback in a specific slot for data received in the previous symbol in the slot. In other cases, the device may provide HARQ feedback in a subsequent slot or according to some other time interval.

[0071] Some UEs (115) and / or base stations (105) may operate in high-mobility environments, such as high-speed train environments. In these environments, base stations (105) may be distributed along tracks or other fixed paths where UEs (115) may move at high speeds. In these cases, it may be difficult for the UE (115) to perform channel estimation for decoding performance due to the high speeds. This difficulty may be more pronounced in NR communications due to high operating frequencies. Some RATs, such as LTE, may support high-speed indicators that the UE can use to improve channel estimation. However, other RATs, such as NR, may not support these indicators and may rely on the UE (115) to detect when operating in a high-speed scenario, but such detection may be associated with resource overhead.

[0072] The implementations described herein support a UE (115) that leverages information determined for a first RAT (e.g., LTE) for communications over a second RAT (e.g., NR). In some examples, these techniques may be applicable in a non-standalone (NSA) network, where LTE and NR access points may be placed in parallel or implemented at the same access point. In such cases, the UE (115) may receive an indication that the UE (115) is operating at high speed. The indication may be an example of a high-speed flag of SIB2. Upon receiving the indication, the UE (215) may activate an operating mode that allows the UE to apply Doppler values ​​determined using a channel estimation procedure in the first RAT (e.g., LTE) to communications in the second RAT (e.g., NR). The Doppler values ​​may be applied to the FTL or TTL in the second RAT. By using these and other techniques described herein, the UE (115) may improve communication efficiency and reduce processing overhead by reducing or limiting the UE channel estimation in one of the RATs.

[0073] FIG. 2 illustrates an example of a wireless communication system (200) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. In some examples, the wireless communication system (200) may include a UE (215), base stations (205), etc., which may be examples of the corresponding devices described with reference to FIG. 1. For example, the base stations (205) may be examples of base stations (105), access network transmitting entities (145), repeaters, transmit / receive points (TRPs), remote radio heads (RRHs), access points (APs), or any combination thereof. Additionally, the base stations (205) may serve the same geographical area or different geographical areas. In some cases, one or more base stations may be juxtaposed with one another. For example, base station (205-a) may be juxtaposed with base station (205-b). In some cases, juxtaposed base stations (e.g., base stations (205-a and 205-b)) may represent multiple cells supported by the same access point. For example, base station (205-a) may represent a first cell and base station (205-b) may represent a second cell. Thus, base stations 205-a and 205-b may correspond to the same access point. The wireless communication system (200) may also include a high-speed train (210). Generally, the high-speed train (210) may be an example of any high-mobility device (e.g., a car) that may move at high speed. The high-speed train (210) may carry any number of UEs (215) configured to support the implementations described herein.

[0074] In some cases, the wireless communication system (200) may support multiple RATs. For example, base stations (205-a and 205-d) (or corresponding embodiments of access points) may be examples of LTE base stations, while base stations (205-b and 205-c) (or corresponding embodiments of access points) may be examples of NR base stations. Each of these base stations may support different communication bandwidths. More specifically, LTE base stations may support communications in radio frequency bands corresponding to LTE communications, while NR base stations may support communications in NR radio frequency bands (e.g., mmW frequencies). In some examples, different RATs may be implemented using a non-standalone (NSA) arrangement so that a first RAT (e.g., LTE) may be used to support communications in a second RAT (e.g., NR). To support NSA deployment, each base station may be placed in parallel, or different RATs may be implemented at the same access point as described in this specification and as illustrated in FIG. 2. Additionally, the UE (215) may be implemented with various components, such as each RF chain, to support communications through multiple RATs, such as LTE and NR.

[0075] In some cases, base stations (205) may be positioned along the train tracks in such a way that they provide continuous or nearly continuous coverage for UEs (215) on the high-speed train (210). In these cases, base stations (205) may be distributed to support communication over various frequencies, such as high frequencies (e.g., mmW frequencies). However, high-speed movement of the UE (215) (e.g., through the high-speed train (210)) combined with communication over various frequencies with distributed base stations (205) may cause communication challenges, including high Doppler fluctuations and difficulties in efficiently estimating channel conditions. Doppler fluctuations (e.g., Doppler shift, Doppler spread, path delays) may occur when the transmitter, the receiver, or both are moving relative to each other. Relative movement may shift and / or spread the frequency of the signal, causing the frequency of the signal at the receiver to be different from that at the transmitter. As such, the frequency perceived by the receiver may differ from the frequency at which the signal was originally transmitted. For example, the UE (215) may receive transmissions from the base station (205-a) via the communication link (225-a) and transmissions from the base station (205-d) via the communication link (225-d), while the UE (215) moves at a speed away from the base station (205-a) and toward the base station (205-d). Transmitters received by the UE (215) from base stations (205-a and 205-d) may both undergo a Doppler shift, or a Doppler diffusion, or both, wherein the Doppler shift and diffusion of the two transmitters may be different (e.g., the UE (215) receives a frequency lower than the transmitter frequency from base station (205-a) and a frequency higher than the transmitter frequency from base station (205-d).In some cases, the Doppler shift may be the same or opposite.

[0076] In some cases, the Doppler shift may be significant enough to introduce communication failures. For example, if the UE (215) monitors the frequency range for transmissions from the base station (205) and the Doppler shift is sufficiently large, the UE (215) may receive a transmission at a different frequency outside the monitoring frequency range (e.g., overlapping with or separated from the monitoring frequency range), thereby interrupting communications between the UE (215) and the base station (205). Therefore, various techniques may be used to account for Doppler shifting in wireless communication systems.

[0077] In some RATs, such as LTE, base stations (205) notify UEs (215) when the UE is operating in a high-speed scenario. In some cases, base stations (205) may determine that the UE (115) is operating in a high-speed scenario by monitoring the speed of the UE and / or by information or signals received from the UE (115). For example, base station (205-b) may be an example of an LTE base station. The UE (215) may communicate with the base station (205-b) via a communication link (225-b) using LTE communication protocols. When the UE (215) is traveling on a high-speed train (210), the base station (205-b) may determine that the UE (215) is operating at high speed by monitoring the speed of the UE (215) or by monitoring signals received from the UE (215) (e.g., reference signals). In some examples, the base station (205-b) may transmit system information (e.g., System Information Block (SIB) type 2) containing a high-speed indication (e.g., highSpeedFlag) to the UE (215). When the UE (215) receives an indication that the UE (215) is operating in a high-speed scenario (e.g., highSpeedFlag is true), the UE (215) may perform one or more various procedures to consider the high-speed scenario. In one example, when the high-speed flag is true, the UE (215) may determine a Random Access Channel (RACH) request preamble using a cyclic shift interval (e.g., N_CS) based on the indication of the high-speed scenario.More specifically, the UE (215) may use a first set of cyclic shift intervals (e.g., a limited set) when the UE (215) is not operating in a high-speed scenario (e.g., when highSpeedFlag is False), and the UE (215) may use a second set of cyclic shift intervals (e.g., an unrestricted set) when the UE (215) is operating in a high-speed flag scenario (e.g., when highSpeedFlag is True). It should be understood that the UE (215) may perform other procedures differently based on the high-speed indication.

[0078] Additionally or alternatively, the UE (215) may use a frequency tracking loop (FTL) or a time tracking loop (TTL) to mitigate Doppler shifting inherent to high-speed movement. While the FTL may be used by the UE (215) to account for errors in frequency detection (e.g., due to Doppler shifting), the time tracking loop (time-delay tracking loop) may be used to account for time delays between the UE (215) and the base stations (205). In some cases, the UE (215) may perform a channel estimation procedure that results in Doppler values ​​among other channel metrics. Doppler values ​​may be used to adjust or applied to the FTL or TTL to provide more accurate frequency and time-delay tracking.

[0079] In some cases, base stations (205) may not transmit system information including high-speed indications. For example, base station (205-a) may be an NR base station that is not configured to indicate that the UE is operating in a high-mobility environment. In these cases, the UE (115) may use various procedures, such as channel estimation procedures, to detect that the UE (215) is operating in a high-mobility environment. However, high-mobility detection may result in significant resource overhead. Additionally, due to the high mobility and speed of the UE (e.g., on a high-speed train (210)), repeating high-speed detection (e.g., channel estimation) may significantly increase this overhead.

[0080] The techniques described in this specification may provide for the UE (215) to use high-speed information from the first base station (205) (e.g., LTE base station) for communication with the second base station (e.g., NR base station).

[0081] As described herein, the UE (215) may be configured to support multiple communications through multiple RATs. For example, the UE (215) may have an LTE RAT component and an NR RAT component. Each RAT component may correspond to RF circuits and logic associated with communications in different RATs. In these cases, the UE (215) may be able to communicate with more than one base station using multiple RATs. For example, base station (205-b) may be an example of an LTE base station, and base station (205-a) may be an NR base station. While the UE (215) may communicate with base station (205-b) over a communication link (225-a) via NR, the UE (215) may also communicate with base station (205-b) over a communication link (225-b) via LTE. As described in this specification, since mobility detection in NR may be resource-intensive, the UE (215) may use information received through a communication link (225-b) (e.g., LTE link) with a base station (205-b) to support communications through a communication link (225-a) (e.g., NR link) with a base station (205-a), and vice versa.

[0082] For example, upon receiving a high-speed indication (e.g., highSpeedFlag is true), the UE (115) may decide to apply information determined using LTE procedures to communications over the NR. In one example, the UE (115) may apply a Doppler value (e.g., frequency offset or value) resulting from a channel estimation procedure over an LTE link (e.g., communication link (225-b)) to communications over an NR link (e.g., communication link (225-a)). This Doppler value may be applied to the FTL and / or TTL corresponding to the NR communications. Thus, rather than performing a channel estimation procedure to generate a Doppler value in the NR, which may be resource-intensive, the UE (215) may apply a Doppler value determined using the LTE link, which may result in reduced processing and resource overhead.

[0083] In some cases, the UE (215) may identify the relationship between base station (205-a) and base station (205-b) (e.g., juxtaposition, proximity frequency bands, non-standalone (NSA) deployment, standalone (SA) deployment, etc.) based on receiving a high-speed indication. To determine the relationship between base stations (205-a and 205-b), during the monitoring period, the UE (215) may monitor a first Doppler metric associated with a first RAT (e.g., determined using a channel estimation procedure) and a second Doppler metric associated with a second RAT. By comparing these Doppler metrics, the UE (215) may determine whether base stations associated with different RATs are juxtaposed or positioned in other patterns, such as alternating patterns. In some cases, the UE (215) may determine Doppler values ​​for each RAT (e.g., using each channel estimation procedure) and decide to drop the determined Doppler values ​​due to differences between the metrics. More specifically, if the metrics indicate that there may be some error in the Doppler shift estimation (e.g., the difference between the values ​​is greater than the Doppler threshold difference), the UE (215) may decide to drop the Doppler values ​​and perform a new channel estimation procedure for one or both RATs to determine new Doppler values.

[0084] As described, the UE (215) may use Doppler values ​​corresponding to communications between the base stations (205-a and 205-b) and the UE (215) to coordinate communication links (225). For example, the UE (215) may apply a first Doppler value to coordinate FTL or TTL for the NR communication link (225-a). In some examples, the UE (215) may directly apply a Doppler value to communications between the base station (205-a) and the UE (215). However, that Doppler value (corresponding to the LTE communication link (225-b)) may not be suitable for the NR communication link (225-a) due to differences in radio frequency bandwidths. For example, the UE (215) may determine that the difference between the first radio frequency spectrum band associated with the NR communication link (225-a) and the second radio frequency spectrum associated with the LTE communication link (225-b) is greater than a frequency threshold. The frequency threshold may be signaled to the UE (215) by one or more of the base stations (205), may be predefined in the UE (215), or may be determined autonomously, etc. In this way, the UE (215) may apply a scaling factor to the Doppler value before applying the Doppler value to communications between the base station (205-a) and the UE (215). The scaling factor may be signaled by one or more of the base stations (205), may be predefined in the UE (215), or may be determined autonomously (e.g., calculated based on frequency curves, trends, etc.). In other examples, the UE (215) may apply a second Doppler value to adjust the FTL or TTL for the LTE communication link (225-b).

[0085] In some cases, the UE (215) may monitor decoding performance metrics associated with downlink communications (e.g., via the LTE communication link (225-b) and the NR communication link (225-a)). Decoding performance metrics may be error rates such as bit rate error, the number of bit flips in the UE (215), throughput, etc. Based on monitoring decoding performance metrics, the UE (215) may determine that the quality of one or more communication links is unsatisfactory (e.g., that the decoding performance metrics satisfy a threshold). As such, the UE (215) may adjust the FTL, TTL, or both for the NR communication link (225-a), the LTE communication link (225-b), or both of these. In some cases, adjusting the TTL, FTL, or both of these for one or more RATs may involve applying Doppler values ​​determined using a channel estimation procedure in other RATs.

[0086] Additionally, as the UE (215) moves on the high-speed train (210), the UE (215) may exit the coverage area corresponding to base stations (205-a and 205-b) and enter the coverage area corresponding to base stations (205-c and 205-d). In this case, the UE (215) may receive a handover command to initiate a handover procedure (e.g., a random access procedure). Likewise, the UE (215) may drop the communication links (225-a and 225-b) and establish communication links (225-c and 225-d) with base stations (205-c and 205-d), respectively. As part of a random access procedure and to establish communications with at least one of the base stations (205-c and 205-d), the UE (215) may generate a random access preamble that is transmitted to one or both of the base stations (205-c and 205-d) in a random access request. The UE (215) may generate a random access preamble based on Doppler values ​​generated using a channel estimation procedure with one of the RATs. For example, if the UE (215) receives a high-speed indication (e.g., from base station (205-b)), the UE (215) may use Doppler values ​​generated along with a set of cyclic shift intervals (e.g., corresponding to the high-speed flag) to generate a random access preamble. In this way, the UE (215) may transmit the random access preamble to base station (205-c) as part of a connection establishment procedure.More specifically, the UE (215) may generate a random access preamble to be transmitted to another base station (e.g., base station (205-d)) associated with a second RAT (e.g., NR) in a random access request, using a high-speed indication (e.g., highSpeedFlag is true) transmitted through the first RAT (e.g., LTE) and a Doppler value determined using a channel estimation procedure in the first RAT.

[0087] The UE (215) may also support the use of information from one RAT to support another RAT by applying an output of FTL or TTL from one RAT to another RAT. For example, the UE (215) may apply an output of FTL or TTL associated with LTE communications to an FTL or TTL associated with NR communications and vice versa (for example, the UE applies an output of NR TTL or FTL to an LTE TTL or FTL). The output may be a frequency offset / spread or a time delay. In some examples, the application of FTL or TTL may be useful in handover scenarios where sudden frequency / time delay changes or aliasing may occur.

[0088] Applying information from communications with the first base station (205) through the first RAT to communications with the second base station (205) through the second RAT may allow the UE (215) to support more efficient connections to the base stations (205), perform channel estimation procedures, and improve system efficiency. Additionally, by monitoring various metrics (e.g., Doppler metrics) associated with the two RATs, the UE may use information identified using the first RAT to perform coordination for communications through the second RAT.

[0089] FIG. 3 illustrates an example of a process flow (300) that supports channel estimation for a plurality of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. The process flow (300) may include a UE (315) which may be an example of a UE (115) or a UE (215) as described with reference to FIG. 1 and FIG. 2, respectively. The process flow (300) may include one or more wireless network devices (e.g., base stations (305)) which may be examples of a base station (105), a base station (205), etc., as described with reference to FIG. 1 and FIG. 2.

[0090] The UE (315) may be an example of a multi-RAT UE (315), wherein the UE (315) may be configured to support more than one RAT. For example, the UE (315) may be configured to support both an LTE RAT for communication with an LTE base station and an NR RAT for communication with an NR base station.

[0091] In some examples, base stations (305) may correspond to different RATs. For example, base station (305-a) may support LTE, while base station (305-b) may support NR. Additionally or alternatively, base station (305-a) or base station (305-b), or both, may be examples of a base station, an IAB node, a repeater node (e.g., composed of some retransmission capability). In some examples, base station (305-a) and base station (305-b) may be distinct entities located in different physical spaces. However, in some examples, base station (305-a) and base station (305-b) may be juxtaposed, or they may be the same network entity operating in the role of a first base station (305) (e.g., as part of a first communication system) and subsequently operating in the role of a second base station (e.g., as part of a second communication system). In some cases, base stations (305) may be included in a deployment (e.g., an NSA system or an SA system). An NSA system may use 4G core networks for the deployment of 5G communications, and an SA system may use 5G core networks and devices for the deployment of 5G communications.

[0092] In some cases, formatting control information, reference signals, data transmissions, etc. may vary between different RATs. For example, a base station (305-a) (e.g., an LTE base station) may transmit control information including a high-speed indication to the UE (315), whereas a base station (305-b) (e.g., an NR base station) may not. The techniques described herein provide for the UE (315) to apply high-speed information from a first communication link to a second communication link.

[0093] In 320, the base station (305-a) may transmit system information to the UE (315). In some cases, the base station (305-a) may include a high-speed indicator within the system information. In some examples, the system information may be SIB2, and the high-speed indicator may be a high-speed flag. The UE (315) may receive the system information.

[0094] In 325, in some cases, the base station (305-a) may also send a handover command to the UE (315) to perform a handover procedure to the base station (305-b).

[0095] In 330, the UE (315) may determine the relationship between base stations (305-a and 305-b) based on receiving indications in 320. The relationship may be the collocation of base stations (305), the proximity of carrier frequencies corresponding to communications with base stations (305), NSA deployment, and SA deployment, etc. When determining the relationship, the UE (315) monitors a first Doppler metric associated with a first radio access technology (e.g., LTE RAT) and monitors a second Doppler metric associated with a second radio access technology (e.g., NR RAT) during the monitoring period. The Doppler metric may be a Doppler value (e.g., frequency offset), time delay, some other value corresponding to the Doppler effect, or a combination thereof.

[0096] In 335, the UE (315) may perform a channel estimation procedure for a first radio access (e.g., associated with an LTE RAT) to generate a Doppler value based on receiving a sign at 320. In some examples, when the UE (315) receives a handover command at 325, the UE (315) may generate a random access preamble for a handover procedure (e.g., a random access request) with a base station (305-a), which is described in more detail with reference to FIG. 2.

[0097] In 340, in some cases, the UE (315) may perform a second channel estimation procedure to generate a second Doppler value associated with communications with the base station (305-a).

[0098] In 345, the UE (315) may determine that the difference between the second Doppler value and the first Doppler value (e.g., the Doppler value generated in 335) is greater than or equal to a Doppler threshold. The Doppler threshold may be signaled to the UE (315) by one or more of the base stations (305), predefined in the UE (315), or determined autonomously, etc.

[0099] In 350, when it is determined that the difference between the first and second Doppler values ​​is greater than the Doppler threshold, the UE (315) may perform a new channel estimation procedure to generate a new Doppler value.

[0100] In 355, in some cases, the UE (315) may identify that the difference between the first radio frequency spectrum associated with the first radio access technology (e.g., LTE RAT) and the second radio frequency spectrum associated with the second radio access technology (e.g., NR RAT) is greater than a frequency threshold. The frequency threshold may be signaled to the UE (315) by one or more of the base stations (305), predefined by the UE (315), or determined autonomously. Thus, the UE (315) may determine an adjusted Doppler value based on a scaling factor associated with the second radio frequency spectrum corresponding to the second radio access technology (e.g., NR RAT). The scaling factor may be signaled by one or more of the base stations (205), predefined by the UE (215), or determined autonomously (e.g., calculated based on frequency curves, trends, etc.).

[0101] In 360, the UE (315) may apply Doppler value(s) to communication links between the UE (315) and one or more of the base stations (305). For example, the UE (315) may apply a generated Doppler value (e.g., a first Doppler value, an adjusted Doppler value, a new Doppler value, etc.) to a communication link between the UE (315) and the base station (305-b). Similarly, the UE (315) may apply another generated Doppler value (e.g., a second Doppler value, a new Doppler value, etc.) to a communication link between the UE (315) and the base station (305-a). Applying Doppler value(s) to communication links may include applying the Doppler value to the FTL or TTL associated with each communication link. For example, the UE (315) may apply a first Doppler value to the FTL of the communication link between the UE (315) and the base station (305-b).

[0102] In 365, the UE (315) may communicate with the base station (305-b). The UE (315) may communicate with the base station (305-b) based on applying the Doppler value generated in 360. In some cases, communicating with the base station (305-b) may include transmitting a random access preamble generated in 335 to the base station (305-b) in response to a handover command in 325.

[0103] In 370, the UE (315) may also monitor decoding performance metrics associated with downlink communications via a first radio access technology (e.g., LTE RAT) and downlink communications via a second radio access technology (e.g., NR RAT). Decoding performance monitoring is described in more detail with reference to FIG. 2.

[0104] Based on monitoring the decoding performance metrics in 375, 370, the UE (315) may adjust the FTL, TTL, or both for a first radio access technology (e.g., LTE RAT), a second radio access technology (e.g., NR RAT), or both. In some cases, the UE (315) may adjust the FTL / TTL by applying the output of the FTL / TTL corresponding to one RAT (e.g., LTE) to the FTL / TTL corresponding to another RAT (e.g., NR).

[0105] FIG. 4 illustrates a block diagram (400) of a device (405) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. The device (405) may be an example of embodiments of the TRP (115) as described herein. The device (405) may include a receiver (410), a transmitter (415), and a communication manager (420). The device (405) may also include a processor. Each of these components may communicate with one another (e.g., via one or more buses).

[0106] The receiver (410) may provide means for receiving information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to channel estimation for multiple radio access technologies in high-speed scenarios), user data, control information, or any combination thereof. The information may be transmitted to other components of the device (405). The receiver (410) may utilize a single antenna or a set of multiple antennas.

[0107] The transmitter (415) may provide means for transmitting signals generated by other components of the device (405). For example, the transmitter (415) may transmit information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to channel estimation for multiple radio access technologies in high-speed scenarios), user data, control information, or any combination thereof. In some examples, the transmitter (415) may be co-located with the receiver (410) in the transceiver module. The transmitter (415) may utilize a single antenna or a set of multiple antennas.

[0108] A communication manager (420), a receiver (410), a transmitter (415), or various combinations thereof or various components thereof may be examples of means for performing various aspects of channel estimation for a number of radio access technologies in high-speed scenarios as described herein. For example, the communication manager (420), the receiver (410), the transmitter (415), or various combinations thereof or components thereof may support a method for performing one or more of the functions described herein.

[0109] In some examples, a communication manager (420), a receiver (410), a transmitter (415), or various combinations or components thereof may be implemented in hardware (e.g., in a communication management circuit). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as a means for performing or otherwise supporting the functions described in this disclosure. In some examples, a processor and memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by executing instructions stored in memory by the processor).

[0110] Additionally or alternatively, in some examples, the communication manager (420), receiver (410), transmitter (415), or various combinations thereof or components may be implemented in code executed by a processor (e.g., as communication management software or firmware). When implemented in code executed by a processor, the functions of the communication manager (420), receiver (410), transmitter (415), or various combinations thereof or components may be performed by a general-purpose processor, DSP, central processing unit (CPU), ASIC, FPGA, or any combination of these or other programmable logic devices (e.g., configured as a means to perform the functions described in this disclosure or otherwise supporting them).

[0111] In some examples, the communication manager (420) may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using the receiver (410), the transmitter (415), or both, or otherwise in cooperation with them. For example, the communication manager (420) may receive information from the receiver (410), transmit information to the transmitter (415), or be integrated in combination with the receiver (410), the transmitter (415), or both, to receive information, transmit information, or perform various other operations as described herein.

[0112] The communication manager (420) may support wireless communications in the UE according to examples as disclosed in this specification. For example, the communication manager (420) may be configured as a means for receiving a high-speed indication associated with the UE's first wireless connection with the first base station from a first base station operating according to a first radio access technology, or otherwise support such. The communication manager (420) may be configured as a means for performing a channel estimation procedure for the first wireless connection to generate a Doppler value based on receiving the high-speed indication, or otherwise support such. The communication manager (420) may be configured as a means for communicating with a second base station operating according to a second radio access technology based on applying the generated Doppler value to a frequency tracking loop or time tracking loop for the UE's second wireless connection with the second base station, or otherwise support such.

[0113] By including or configuring a communication manager (420) according to examples described herein, the device (405) (e.g., a processor controlling a receiver (410), a transmitter (415), a communication manager (420), or a combination thereof, or coupled thereto in a different way) may support techniques for reducing processing overhead by reducing processor-intensive channel estimation in high radio frequency bands (e.g., NR mmW bands) by using channel estimation information determined using a lower radio frequency band (e.g., LTE band).

[0114] FIG. 5 illustrates a block diagram (500) of a device (505) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. The device (505) may be an example of embodiments of the device (405) or UE (115) as described herein. The device (505) may include a receiver (510), a transmitter (515), and a communication manager (520). The device (505) may also include a processor. Each of these components may communicate with one another (e.g., via one or more buses).

[0115] The receiver (510) may provide means for receiving information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to channel estimation for multiple radio access technologies in high-speed scenarios), user data, control information, or any combination thereof. The information may be transmitted to other components of the device (505). The receiver (510) may utilize a single antenna or a set of multiple antennas.

[0116] The transmitter (515) may provide means for transmitting signals generated by other components of the device (505). For example, the transmitter (515) may transmit information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to channel estimation for multiple radio access technologies in high-speed scenarios), user data, control information, or any combination thereof. In some examples, the transmitter (515) may be juxtaposed with the receiver (510) in the transceiver module. The transmitter (515) may utilize a single antenna or a set of multiple antennas.

[0117] The device (505) or various components thereof may be examples of means for performing various aspects of channel estimation for a number of radio access technologies in a high-speed scenario as described herein. For example, the communication manager (520) may include a high-speed display interface (525), a channel estimation component (530), a communication interface (535), or any combination thereof. The communication manager (520) may be an example of an aspect of the communication manager (420) as described herein. In some examples, the communication manager (520) or various components thereof may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using a receiver (510), a transmitter (515), or both, or otherwise in cooperation with them. For example, the communication manager (520) may receive information from the receiver (510), transmit information to the transmitter (515), or be integrated with the receiver (510), the transmitter (515), or both to receive or transmit information, or perform various other operations as described in this specification.

[0118] The communication manager (520) may support wireless communications in the UE according to examples as disclosed in this specification. The high-speed indication interface (525) may be configured as a means for receiving a high-speed indication associated with the UE's first wireless connection with the first base station from a first base station operating according to a first radio access technology, or otherwise may support such an indication. The channel estimation component (530) may be configured as a means for performing a channel estimation procedure for the first wireless connection to generate a Doppler value based on receiving the high-speed indication, or otherwise may support such an indication. The communication interface (535) may be configured as a means for communicating with a second base station operating according to a second radio access technology based on applying the generated Doppler value to a frequency tracking loop or time tracking loop for the UE's second wireless connection with the second base station, or otherwise may support such an indication.

[0119] FIG. 6 illustrates a block diagram (600) of a communication manager (620) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. The communication manager (620) may be an example of embodiments of the communication manager (420), the communication manager (520), or both as described herein. The communication manager (620) or various components thereof may be examples of means for performing various embodiments of channel estimation for a number of radio access technologies in a high-speed scenario as described herein. For example, the communication manager (620) may include a high-speed display interface (625), a channel estimation component (630), a communication interface (635), a control interface (640), a RACH component (645), a RAT adjustment component (650), a decoding performance component (655), a RAT comparison component (660), a system information interface (665), a Doppler comparison component (670), or any combination thereof. Each of these components may communicate with one another directly or indirectly (e.g., through one or more buses).

[0120] The communication manager (620) may support wireless communications in the UE according to examples as disclosed in this specification. The high-speed indication interface (625) may be configured as a means for receiving a high-speed indication associated with the UE's first wireless connection with the first base station from a first base station operating according to a first radio access technology, or otherwise may support such an indication. The channel estimation component (630) may be configured as a means for performing a channel estimation procedure for the first wireless connection to generate a Doppler value based on receiving the high-speed indication, or otherwise may support such an indication. The communication interface (635) may be configured as a means for communicating with a second base station operating according to a second radio access technology based on applying the generated Doppler value to a frequency tracking loop or time tracking loop for the UE's second wireless connection with the second base station, or otherwise may support such an indication.

[0121] In some examples, the control interface (640) may be configured as a means for receiving a command to perform a handover procedure to a second base station, or otherwise support it. In some examples, the RACH component (645) may be configured as a means for generating a random access preamble for a handover procedure to a second base station using a Doppler value generated using a channel estimation procedure with a first base station based on receiving the command, or otherwise support it, wherein communication with the second base station is included. In some examples, the RACH component (645) may be configured as a means for transmitting the random access preamble generated in response to the received command to the second base station, or otherwise support it.

[0122] In some examples, the Doppler value includes a first Doppler value, and the channel estimation component (630) may be configured as a means for performing a second channel estimation procedure to generate a second Doppler value associated with communications with a second base station operating using a second radio access technique, or may otherwise support it. In some examples, the Doppler value includes a first Doppler value, and the RAT adjustment component (650) may be configured as a means for applying a second Doppler value to communications with a first base station using a first radio access technique, or may otherwise support it.

[0123] In some examples, to support the application of a second Doppler value, the RAT adjustment component (650) may be configured as a means for adjusting a frequency tracking loop or a time tracking loop for a first radio connection with a first base station operating according to a first radio access technology, or otherwise may support this.

[0124] In some examples, the Doppler comparison component (670) may be configured as a means to determine that the difference between the second Doppler value and the first Doppler value is greater than or equal to the Doppler threshold, or otherwise support this. In some examples, the channel estimation component (630) may be configured as a means to perform a new channel estimation procedure for the first wireless access to generate a new Doppler value based on determining that the difference is greater than or equal to the Doppler threshold, or otherwise support this.

[0125] In some examples, the decoding performance component (655) may be configured as a means for monitoring decoding performance metrics associated with downlink communications via the first radio access technology and downlink communications via the second radio access technology, or otherwise may support this. In some examples, the RAT coordination component (650) may be configured as a means for coordinating a time tracking loop, a frequency tracking loop, or both for the first radio access technology, the second radio access technology, or both, based on monitoring decoding performance metrics, or otherwise may support this.

[0126] In some examples, the RAT comparison component (660) may be configured as a means to determine the relationship between the first base station associated with the first radio access technology and the second base station associated with the second radio access technology by monitoring the first Doppler metric associated with the first radio access technology and the second Doppler metric associated with the second radio access technology during the monitoring period based on receiving an indication, or may otherwise support it.

[0127] In some examples, the RAT adjustment component (650) may be configured as a means for applying an adjusted Doppler value to adjust a frequency tracking loop or a time tracking loop for a second wireless connection based on the generated Doppler value, or may otherwise support it.

[0128] In some examples, the RAT adjustment component (650) may be configured as a means for determining an adjusted Doppler value based on a scaling factor associated with a second radio frequency spectrum band corresponding to the second radio access technology, or otherwise may support this.

[0129] In some examples, the RAT adjustment component (650) may be configured as a means to apply a scaling factor when the difference between the first radio frequency spectrum band and the second radio frequency spectrum band associated with the first radio access technology is greater than or equal to a frequency threshold, or otherwise may support it.

[0130] In some examples, to support receiving a display, the system information interface (665) may be configured as a means for receiving system information including a high-speed display from a first base station, or otherwise may support it.

[0131] In some examples, the system information is the system information block type 2 (SIB2), and the high-speed indication is the high-speed flag in the SIB.

[0132] In some examples, the first radio access technology operates in the first radio frequency spectrum band, and the second radio access technology operates in the second radio frequency spectrum band.

[0133] FIG. 7 illustrates a diagram of a system (700) comprising a device (705) that supports channel estimation for a plurality of wireless access technologies in a high-speed scenario according to embodiments of the present disclosure. The device (705) may be an example of or may include components of a device (405), a device (505), or a UE (115) as described herein. The device (705) may communicate wirelessly with one or more base stations (105), UEs (115), or any combination thereof. The device (705) may include components for bidirectional voice and data communications, such as a communication manager (720), an input / output (I / O) controller (710), a transceiver (715), an antenna (725), a memory (730), a code (735), and a processor (740), for transmitting and receiving communications. These components may communicate electronically through one or more buses (e.g., bus (745)) or otherwise be coupled (e.g., operablely, communically, functionally, electronically, electrically).

[0134] The I / O controller (710) may manage input and output signals for the device (705). The I / O controller (710) may also manage peripherals that are not integrated into the device (705). In some cases, the I / O controller (710) may represent a physical connection or port to an external peripheral. In some cases, the I / O controller (710) may utilize an operating system such as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS / 2®, UNIX®, LINUX®, or other known operating systems. Additionally or alternatively, the I / O controller (710) may represent and interact with a modem, keyboard, mouse, touchscreen, or similar device. In some cases, the I / O controller (710) may be implemented as part of a processor, such as the processor (740). In some cases, the user may interact with the device (705) through the I / O controller (1015) or through hardware components controlled by the I / O controller (710).

[0135] In some cases, the device (705) may include a single antenna (725). However, in some other cases, the device (705) may have more than one antenna (725) capable of simultaneously transmitting or receiving multiple wireless transmissions. The transceiver (715) may communicate bidirectionally through one or more antennas (725), wired or wireless links, as described herein. For example, the transceiver (715) may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver (715) may also include a modem for modulating packets, providing the modulated packets to one or more antennas (725) for transmission, and demodulating packets received from one or more antennas (725). The transceiver (715), or the transceiver (715) and one or more antennas (725) may be an example of a transmitter (415), a transmitter (515), a receiver (410), a receiver (510), or any combination thereof or a component thereof, as described herein.

[0136] Memory (730) may include random access memory (RAM) and read-only memory (ROM). Memory (730) may store computer-readable, computer-executable code (735) containing instructions that, when executed by the processor (740), enable the device (705) to perform the various functions described herein. The code (735) may be stored in a non-transient computer-readable medium, such as system memory or other types of memory. In some cases, the code (735) may not be directly executable by the processor (740), but may enable the computer to perform the functions described herein (e.g., when compiled and executed). In some cases, memory (730) may include a basic I / O system (BIOS) that, among other things, may control basic hardware or software operations, such as interactions with peripheral components or devices.

[0137] The processor (740) may include intelligent hardware devices (e.g., general-purpose processor, DSP, CPU, microcontroller, ASIC, FPGA, programmable logic device, discrete gate or transistor logic component, discrete hardware component, or any combination thereof). In some cases, the processor (740) may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor (740). The processor (740) may be configured to execute computer-readable instructions stored in memory (e.g., memory (730)) to enable the device (705) to perform various functions (e.g., functions or tasks supporting channel estimation for multiple radio access technologies in high-speed scenarios). For example, the device (705) or a component of the device (705) may include a processor (740) and a memory (730) coupled to the processor (740), and the processor (740) and the memory (730) are configured to perform various functions described in this specification.

[0138] The communication manager (720) may support wireless communications in the UE according to examples as disclosed herein. For example, the communication manager (720) may be configured as a means for receiving a high-speed indication associated with the UE's first wireless connection with the first base station from a first base station operating according to a first radio access technology, or otherwise support such. The communication manager (720) may be configured as a means for performing a channel estimation procedure for the first wireless connection to generate a Doppler value based on receiving the high-speed indication, or otherwise support such. The communication manager (720) may be configured as a means for communicating with a second base station operating according to a second radio access technology based on applying the generated Doppler value to a frequency tracking loop or time tracking loop for the UE's second wireless connection with the second base station, or otherwise support such.

[0139] By including or configuring a communication manager (720) according to examples as described herein, the device (705) may support techniques for improved communication reliability and efficient utilization of communication resources. For example, by applying a Doppler value determined using a channel estimation procedure performed on a first RAT (e.g., LTE) based on receiving a high-speed indication to another RAT (e.g., NR), the UE may avoid or limit the use of resources associated with channel estimation in the second RAT. Additionally, the UE may use communication information determined for one or both RATs to cross-check communication efficiency in the other RAT to determine whether to coordinate various modes of communication.

[0140] In some examples, the communication manager (720) may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise cooperating with the transceiver (715), one or more antennas (725), or any combination thereof. Although the communication manager (720) is exemplified as a separate component, in some examples, one or more functions described with reference to the communication manager (720) may be supported by or performed by the processor (740), memory (730), code (735), or any combination thereof. For example, the code (735) may include instructions executable by the processor (740) to enable the device (705) to perform various modes of channel estimation for multiple radio access technologies in high-speed scenarios as described herein, or the processor (740) and memory (730) may otherwise be configured to perform or support such operations.

[0141] FIG. 8 illustrates a flowchart illustrating a method (800) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. Operations of method (800) may be implemented by a UE or its components as described herein. For example, operations of method (800) may be performed by a UE (115) as described with reference to FIGS. 1 through 7. In some examples, the UE may execute a set of commands to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use special-purpose hardware to perform embodiments of the described functions.

[0142] In 805, the method may include the step of receiving a high-speed indication associated with the UE's first radio connection with the first base station from a first base station operating according to the first radio access technology. The operations of 805 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 805 may be performed by a high-speed indication interface (625) as described with reference to FIG. 6.

[0143] In 810, the method may include the step of performing a channel estimation procedure for a first wireless access to generate a Doppler value based on receiving a high-speed indication. The operations of 810 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 810 may be performed by a channel estimation component (630) as described with reference to FIG. 6.

[0144] In 815, the method may include the step of communicating with a second base station operating according to a second radio access technique based on applying a Doppler value generated in a frequency tracking loop or a time tracking loop for the UE's second radio access with the second base station. The operations of 815 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 815 may be performed by a communication interface (635) as described with reference to FIG. 6.

[0145] FIG. 9 illustrates a flowchart illustrating a method (900) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. Operations of method (900) may be implemented by a UE or its components as described herein. For example, operations of method (900) may be performed by a UE (115) as described with reference to FIGS. 1 through 7. In some examples, the UE may execute a set of commands to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may perform embodiments of the described functions using special-purpose hardware.

[0146] In 905, the method may include the step of receiving a high-speed indication associated with the UE's first radio connection with the first base station from a first base station operating according to the first radio access technology. The operations of 905 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 905 may be performed by a high-speed indication interface (625) as described with reference to FIG. 6.

[0147] In 910, the method may include the step of performing a channel estimation procedure for a first wireless access to generate a Doppler value based on receiving a high-speed indication. The operations of 910 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 910 may be performed by a channel estimation component (630) as described with reference to FIG. 6.

[0148] In 915, the method may include the step of performing a second channel estimation procedure to generate a second Doppler value associated with communications with a second base station operating using a second radio access technique. The operations of 915 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 915 may be performed by a channel estimation component (630) as described with reference to FIG. 6.

[0149] In 920, the method may include the step of applying a second Doppler value to communications with a first base station using a first radio access technology. The operations of 920 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 920 may be performed by a RAT adjustment component (650) as described with reference to FIG. 6.

[0150] In 925, the method may include the step of communicating with a second base station operating according to a second radio access technique based on applying a Doppler value generated in a frequency tracking loop or a time tracking loop for the UE's second radio access with the second base station. The operations of 925 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 925 may be performed by a communication interface (635) as described with reference to FIG. 6.

[0151] FIG. 10 illustrates a flowchart illustrating a method (1000) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. Operations of the method (1000) may be implemented by a UE or its components as described herein. For example, operations of the method (1000) may be performed by a UE (115) as described with reference to FIGS. 1 through 7. In some examples, the UE may execute a set of commands to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may perform embodiments of the described functions using special-purpose hardware.

[0152] In 1005, the method may include the step of receiving a high-speed indication associated with the UE's first radio connection with the first base station from a first base station operating according to the first radio access technology. The operations of 1005 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1005 may be performed by a high-speed indication interface (625) as described with reference to FIG. 6.

[0153] In 1010, the method may include the step of performing a channel estimation procedure for a first wireless access to generate a Doppler value based on receiving a high-speed indication. The operations of 1010 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1010 may be performed by a channel estimation component (630) as described with reference to FIG. 6.

[0154] In 1015, the method may include the step of performing a second channel estimation procedure to generate a second Doppler value associated with communications with a second base station operating using a second radio access technique. The operations of 1015 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1015 may be performed by a channel estimation component (630) as described with reference to FIG. 6.

[0155] In 1020, the method may include the step of applying an adjusted Doppler value to adjust a frequency tracking loop or a time tracking loop for a second wireless access based on the generated Doppler value. The operations of 1020 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1020 may be performed by a RAT adjustment component (650) as described with reference to FIG. 6.

[0156] In 1025, the method may include the step of applying a second Doppler value to communications with a first base station using a first radio access technology. The operations of 1025 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1025 may be performed by a RAT adjustment component (650) as described with reference to FIG. 6.

[0157] In 1030, the method may include the step of coordinating a frequency tracking loop or a time tracking loop for a first radio connection with a first base station operating according to a first radio access technology. The operations of 1030 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1030 may be performed by a RAT coordination component (650) as described with reference to FIG. 6.

[0158] In 1035, the method may include the step of communicating with a second base station operating according to a second radio access technique based on applying a Doppler value generated in a frequency tracking loop or a time tracking loop for a second radio access of the UE with the second base station. The operations of 1035 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1035 may be performed by a communication interface (635) as described with reference to FIG. 6.

[0159] FIG. 11 illustrates a flowchart illustrating a method (1100) that supports channel estimation for a number of radio access technologies in a high-speed scenario according to embodiments of the present disclosure. Operations of the method (1100) may be implemented by a UE or its components as described herein. For example, operations of the method (1100) may be performed by a UE (115) as described with reference to FIGS. 1 through 7. In some examples, the UE may execute a set of commands to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may perform embodiments of the described functions using special-purpose hardware.

[0160] In 1105, the method may include the step of receiving a high-speed indication associated with the UE's first radio connection with the first base station from a first base station operating according to the first radio access technology. The operations of 1105 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1105 may be performed by a high-speed indication interface (625) as described with reference to FIG. 6.

[0161] In 1110, the method may include the step of receiving system information including a high-speed indication from a first base station. The operations of 1110 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1110 may be performed by a system information interface (665) as described with reference to FIG. 6.

[0162] In 1115, the method may include the step of performing a channel estimation procedure for a first wireless access to generate a Doppler value based on receiving a high-speed indication. The operations of 1115 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1115 may be performed by a channel estimation component (630) as described with reference to FIG. 6.

[0163] In 1120, the method may include the step of communicating with a second base station operating according to a second radio access technique based on applying a Doppler value generated in a frequency tracking loop or a time tracking loop for the UE's second radio access with the second base station. The operations of 1120 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1120 may be performed by a communication interface (635) as described with reference to FIG. 6.

[0164] The following provides an overview of the embodiments of the present disclosure:

[0165] Aspect 1: A method for wireless communications in a UE, comprising: receiving a high-speed indication associated with a first wireless connection of the UE with the first base station from a first base station operating according to a first radio access technique; performing a channel estimation procedure for the first wireless connection to generate a Doppler value based at least partially on receiving the high-speed indication; and communicating with a second base station operating according to a second radio access technique, based at least partially on applying the generated Doppler value to a frequency tracking loop or a time tracking loop for a second wireless connection of the UE with the second base station.

[0166] Aspect 2: A method according to Aspect 1, comprising: receiving a command for performing a handover procedure to the second base station; and, at least partially based on receiving the command, generating a random access preamble for the handover procedure to the second base station using the Doppler value generated using the channel estimation procedure with the first base station, wherein the step of communicating with the second base station further comprises the step of transmitting the random access preamble to the second base station in response to the received command, the step of generating the random access preamble further comprising the step of transmitting the random access preamble.

[0167] Embodiment 3: A method of any one of embodiments 1 to 2, wherein the Doppler value comprises a first Doppler value, and the method further comprises: performing a second channel estimation procedure to generate a second Doppler value associated with communications with the second base station operating using the second radio access technique; and applying the second Doppler value to communications with the first base station using the first radio access technique.

[0168] Aspect 4: A method according to Aspect 3, wherein the step of applying a second Doppler value comprises the step of adjusting a frequency tracking loop or a time tracking loop for a first radio connection with a first base station operating according to a first radio access technique.

[0169] Aspect 5: A method of any one of Aspects 3 to 4, further comprising the step of determining that the difference between the second Doppler value and the first Doppler value is greater than or equal to a Doppler threshold; and the step of performing a new channel estimation procedure for the first wireless access to generate a new Doppler value based at least partially on the determination that the difference is greater than or equal to the Doppler threshold.

[0170] Aspect 6: A method of any one of Aspects 1 to 5, comprising the step of monitoring a decoding performance metric associated with downlink communications through a first radio access technology and downlink communications through a second radio access technology; and further comprising the step of coordinating a time tracking loop, a frequency tracking loop, or both of the first radio access technology, the second radio access technology, or both thereof, at least in part based on monitoring the decoding performance metric.

[0171] Aspect 7: A method of any one of Aspects 1 to 6, further comprising the step of determining the relationship between a first base station associated with a first radio access technology and a second base station associated with a second radio access technology by monitoring a first Doppler metric associated with a first radio access technology and a second Doppler metric associated with a second radio access technology during a monitoring period, at least partially based on receiving an indication.

[0172] Aspect 8: A method of any one of Aspects 1 to 7, further comprising the step of applying an adjusted Doppler value to adjust a frequency tracking loop or a time tracking loop for a second wireless access at least partially based on a generated Doppler value.

[0173] Aspect 9: The method of Aspect 8, further comprising the step of determining an adjusted Doppler value based at least partially on a scaling factor associated with a second radio frequency spectrum band corresponding to a second radio access technology.

[0174] Embodiment 10: The method of Embodiment 9, further comprising the step of applying a scaling factor when the difference between a first radio frequency spectrum band and a second radio frequency spectrum band associated with a first radio access technology is greater than or equal to a frequency threshold.

[0175] Aspect 11: A method of any one of Aspects 1 to 10, wherein the step of receiving the indication comprises receiving system information including the high-speed indication from the first base station.

[0176] Aspect 12: A method according to Aspect 11, wherein the system information is a system information block type 2 (SIB2) and the high-speed indication is a high-speed flag in the SIB.

[0177] Aspect 13: A method of any one of Aspects 1 to 12, wherein the first radio access technology operates in a first radio frequency spectrum band and the second radio access technology operates in a second radio frequency spectrum band.

[0178] Aspect 14: A device for wireless communication in a UE, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to enable the device to perform the method of any one of Aspects 1 to 13.

[0179] Aspect 15: A device for wireless communication in a UE, comprising at least one means for performing the method of any one of Aspects 1 to 13.

[0180] Aspect 16: A non-transient computer-readable medium for storing code for wireless communication in a UE, wherein the code comprises instructions executable by a processor to perform the method of any one of Aspects 1 to 13.

[0181] It should be noted that the methods described herein describe possible implementations, and that the operations and steps may be rearranged or otherwise modified, and that other implementations are possible. Additionally, modes from two or more of the methods may be combined.

[0182] Although embodiments of LTE, LTE-A, LTE-A Pro, or NR systems may be described for illustrative purposes and the terms LTE, LTE-A, LTE-A Pro, or NR may be used in most descriptions, the techniques described herein are applicable to networks other than LTE, LTE-A, LTE-A Pro, or NR. For example, the described techniques may be applicable to various other wireless communication systems, such as UMB (Ultra Mobile Broadband), IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and wireless technologies not explicitly mentioned herein.

[0183] The information and signals described herein may be represented using any various different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be mentioned throughout the description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0184] The various exemplary blocks and components described in connection with the disclosure herein may be implemented or performed as general-purpose processors, DSPs, ASICs, CPUs, FPGAs or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration).

[0185] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. Where implemented in software executed by a processor, the functions may be stored on or transmitted through a computer-readable medium as one or more instructions or code. Other examples and implementations are within the scope of this disclosure and the appended claims. For example, due to the nature of the software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination thereof. Features implementing the functions may also be physically located at various positions, including distributed so that parts of the functions are implemented at different physical locations.

[0186] Computer-readable media include both communication media comprising any medium that facilitates the transmission of a computer program from one place to another, and non-transient computer storage media. A non-transient storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By example, but not by limitation, non-transient computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disc storage, magnetic disc storage or other magnetic storage devices, or any other non-transient medium that may be used to record or store desired program code means in the form of instructions or data structures and may be accessed by a general-purpose or special-purpose computer or a general-purpose or special-purpose processor. Additionally, any connection is appropriately named as a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, the definition of computer-readable media includes coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave. Disks and discs, as used herein, include CDs, laser discs, optical discs, digital multifunction discs (DVDs), floppy discs, and Blu-ray discs, wherein disks typically reproduce data magnetically, while discs reproduce data optically using lasers. Combinations of the above are also included within the scope of computer-readable media.

[0187] As used herein, including in the claims, the word “or” as used in a list of items (e.g., a list of items beginning with phrases such as “at least one of” or “one or more of”) indicates a comprehensive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A, B, and C). Furthermore, as used herein, the phrase “based on” should not be interpreted as a reference to a closed set of conditions. For example, an exemplary step described as “based on condition A” may be based on both condition A and condition B without departing from the scope of this disclosure. That is, as used herein, the phrase “based on” should be interpreted in the same way as the phrase “at least partially based on”.

[0188] The term “decision” or “decision” encompasses a wide variety of actions, and thus “decision” may include calculation, computing, processing, derivation, investigation, inquiry (e.g., through querying a table, database, or other data structure), verification, etc. Additionally, “decision” may include receiving (such as receiving information), access (such as accessing data in memory), etc. Additionally, “decision” may include solving, selecting, electing, establishing, and other such similar actions.

[0189] In the attached drawings, similar components or features may have the same reference label. Additionally, various components of the same type may be distinguished by having a dash and a second label that distinguishes between similar components following the reference label. If only the first reference label is used in this specification, the description is applicable to any component among similar components having the same first reference label, regardless of the second reference label or other subsequent reference labels.

[0190] The description provided herein in connection with the accompanying drawings describes exemplary configurations and does not represent all examples that may be implemented or are within the scope of the claims. As used herein, the term “example” means “an example, case, or functioning as an example,” and does not mean “advantageous over other examples” or “preferable.” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some cases, known structures and devices are depicted in block diagram form to avoid obscuring the concepts of the described examples.

[0191] The description in this specification is provided to enable those skilled in the art to manufacture and use the present disclosure. Various modifications to the present disclosure will be apparent to those skilled in the art, and general principles defined in this specification may be applied to other variations without departing from the scope of the present disclosure. Accordingly, the present disclosure is not limited to the examples and designs described in this specification, but is consistent with the broadest scope of the principles and novel features disclosed in this specification.

Claims

Claim 1 A method for wireless communication in a user device (UE), comprising: receiving a high-speed indication associated with a first wireless connection of the UE with the first base station from a first base station operating according to a first radio access technique; performing a channel estimation procedure for the first wireless connection to generate a Doppler value based at least partially on receiving the high-speed indication; and communicating with the second base station operating according to a second radio access technique, based at least partially on applying the generated Doppler value to a frequency tracking loop or a time tracking loop for a second wireless connection of the UE with the second base station. Claim 2 A method for wireless communication in user equipment according to claim 1, wherein the method further comprises: receiving a command for performing a handover procedure to the second base station; and, at least partially based on receiving the command, generating a random access preamble for the handover procedure to the second base station using the Doppler value generated using the channel estimation procedure with the first base station, and the step of communicating with the second base station comprises transmitting the generated random access preamble to the second base station in response to the received command. Claim 3 A method for wireless communication in user equipment, wherein, in claim 1, the Doppler value includes a first Doppler value, and the method further comprises: performing a second channel estimation procedure to generate a second Doppler value associated with communications with the second base station operating using the second radio access technique; and applying the second Doppler value to communications with the first base station using the first radio access technique. Claim 4 A method for wireless communication in user equipment, wherein the step of applying the second Doppler value comprises the step of adjusting a frequency tracking loop or a time tracking loop for the first wireless connection with the first base station operating according to the first radio access technology. Claim 5 A method for wireless communication in user equipment according to claim 3, further comprising: a step of determining that the difference between the second Doppler value and the first Doppler value is greater than or equal to a Doppler threshold; and a step of performing a new channel estimation procedure for the first wireless connection to generate a new Doppler value based at least partially on determining that the difference is greater than or equal to the Doppler threshold. Claim 6 A method for wireless communication in user equipment according to claim 1, further comprising: a step of monitoring a decoding performance metric associated with downlink communications through the first radio access technology and downlink communications through the second radio access technology; and a step of adjusting the time tracking loop, the frequency tracking loop, or both for the first radio access technology, the second radio access technology, or both, at least in part based on monitoring the decoding performance metric. Claim 7 A method for wireless communication in user equipment according to claim 1, further comprising the step of determining the relationship between the first base station associated with the first radio access technology and the second base station associated with the second radio access technology by monitoring the first Doppler metric associated with the first radio access technology and the second Doppler metric associated with the second radio access technology during a monitoring period, at least partially based on receiving the indication. Claim 8 A device for wireless communication in a user device (UE), comprising: a processor; a memory coupled to the processor; and instructions stored in the memory, wherein the instructions are executable by the processor to: receive a high-speed indication associated with a first wireless connection of the UE with the first base station from a first base station operating according to a first radio access technology; perform a channel estimation procedure for the first wireless connection to generate a Doppler value based at least partially on receiving the high-speed indication; and communicate with the second base station operating according to a second radio access technology based at least partially on applying the generated Doppler value to a frequency tracking loop or a time tracking loop for a second wireless connection of the UE with the second base station. Claim 9 In claim 8, the commands are further executable by the processor to cause the device to: receive a command to perform a handover procedure to the second base station; and, at least partially based on receiving the command, to generate a random access preamble for the handover procedure to the second base station using the Doppler value generated using the channel estimation procedure with the first base station, and communicating with the second base station comprises transmitting the generated random access preamble to the second base station in response to the received command. Claim 10 A device for wireless communication in user equipment, wherein, in claim 8, the Doppler value includes a first Doppler value, and the commands are further executable by the processor to cause the device to: perform a second channel estimation procedure to generate a second Doppler value associated with communications with the second base station operating using the second radio access technique; and apply the second Doppler value to communications with the first base station using the first radio access technique. Claim 11 A device for wireless communication in user equipment, wherein, in claim 10, the commands for applying the second Doppler value are executable by the processor to cause the device to: adjust a frequency tracking loop or a time tracking loop for the first wireless connection with the first base station operating according to the first radio access technology. Claim 12 A device for wireless communication in user equipment, wherein, in claim 10, the commands are further executable by the processor to cause the device to determine that the difference between the second Doppler value and the first Doppler value is greater than or equal to a Doppler threshold; and, at least partially based on determining that the difference is greater than or equal to the Doppler threshold, to perform a new channel estimation procedure for the first wireless connection to generate a new Doppler value. Claim 13 A device for wireless communication in user equipment, wherein, in claim 8, the commands are further executable by the processor to cause the device to: monitor a decoding performance metric associated with downlink communications through the first radio access technology and downlink communications through the second radio access technology; and, at least in part, to coordinate the time tracking loop, the frequency tracking loop, or both for the first radio access technology, the second radio access technology, or both. Claim 14 A device for wireless communication in user equipment, wherein, in claim 8, the commands are further executable by the processor to cause the device to: determine the relationship between the first base station associated with the first radio access technology and the second base station associated with the second radio access technology by monitoring the first Doppler metric associated with the first radio access technology and the second Doppler metric associated with the second radio access technology during a monitoring period, at least in part, based on receiving the indication. Claim 15 A device for wireless communication in user equipment, wherein, in claim 8, the commands are further executable by the processor to cause the device to: apply an adjusted Doppler value to adjust the frequency tracking loop or the time tracking loop for the second wireless connection based at least partially on the generated Doppler value. Claim 16 A device for wireless communication in user equipment, wherein, in claim 15, the commands are further executable by the processor to cause the device to determine the adjusted Doppler value based at least partially on a scaling factor associated with a second radio frequency spectrum band corresponding to the second radio access technology. Claim 17 A device for wireless communication in user equipment, wherein, in claim 16, the commands are further executable by the processor to cause the device to: apply the scaling factor when the difference between the first radio frequency spectrum band associated with the first radio access technology and the second radio frequency spectrum band is greater than or equal to a frequency threshold. Claim 18 In claim 8, the commands for receiving the indication are executable by the processor to cause the device to: receive system information including the high-speed indication from the first base station, a device for wireless communication in user equipment. Claim 19 A device for wireless communication in user equipment, wherein, in claim 18, the system information is a system information block type 2 (SIB2) and the high-speed indication is a high-speed flag in the system information block (SIB). Claim 20 A device for wireless communication in user equipment, wherein, in claim 8, the first radio access technology operates in a first radio frequency spectrum band and the second radio access technology operates in a second radio frequency spectrum band. Claim 21 delete Claim 22 delete Claim 23 delete Claim 24 delete Claim 25 delete Claim 26 delete Claim 27 delete Claim 28 delete Claim 29 delete Claim 30 delete

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