US-20260129525-A1 - TECHNIQUES FOR CELL HANDOVER USING APERIODIC CHANNEL STATE INFORMATION REFERENCE SIGNALS

US20260129525A1US 20260129525 A1US20260129525 A1US 20260129525A1US-20260129525-A1

Abstract

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive, from a serving cell, a control signal indicating a set of parameters for a target cell available for handover for the UE and indicating the target cell is configured to transmit an aperiodic reference signal during a handover procedure. The UE may receive a command that identifies the target cell for a handover from the serving cell, and the command may indicate one or more resources associated with the aperiodic reference signal. The UE may receive, from the target cell, the aperiodic reference signal over the one or more resources. The UE may transmit a random access message based on time information or frequency information obtained from the aperiodic reference signal.

Inventors

Sandeep Kumar Aitha
Changhwan Park
Mahdi Zamani
Dominic BOIKO

Assignees

QUALCOMM INCORPORATED

Dates

Publication Date: 20260507
Application Date: 20241107

Claims (20)

1 . A user equipment (UE), comprising: one or more memories storing processor-executable code; and one or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the UE to: receive, from a serving cell, a control signal indicating a set of parameters for a target cell available for handover for the UE and indicating the target cell is configured to transmit an aperiodic reference signal during a handover procedure; receive, from the serving cell, a command that identifies the target cell for a handover from the serving cell, wherein the command indicates one or more resources associated with the aperiodic reference signal; receive, from the target cell, the aperiodic reference signal over the one or more resources; and transmit, based at least in part on the aperiodic reference signal, a random access message based at least in part on time information or frequency information obtained from the aperiodic reference signal.
2 . The UE of claim 1 , wherein, to receive the aperiodic reference signal, the one or more processors are individually or collectively operable to execute the code to cause the UE to: receive the aperiodic reference signal in accordance with a configuration, indicated by the set of parameters, for the one or more resources.
3 . The UE of claim 2 , wherein, to receive the aperiodic reference signal, the one or more processors are individually or collectively operable to execute the code to cause the UE to: receive the aperiodic reference signal after a time duration.
4 . The UE of claim 2 , wherein the configuration indicates a quantity of the one or more resources.
5 . The UE of claim 2 , wherein the one or more resources comprise a plurality of subsets of resources including first subset of resources and a second subset of resources separated by a time gap.
6 . The UE of claim 5 , wherein the configuration indicates a quantity of the plurality of subsets of resources and indicates a duration for the time gap.
7 . The UE of claim 1 , wherein, to receive the command, the one or more processors are individually or collectively operable to execute the code to cause the UE to: receive the command that indicates an identification associated with the one or more resources.
8 . The UE of claim 1 , wherein, to receive the command, the one or more processors are individually or collectively operable to execute the code to cause the UE to: receive the command that indicates the one or more resources associated with the aperiodic reference signal as a time duration after reception of the command, wherein receiving the aperiodic reference signal comprises: receive the aperiodic reference signal after the time duration.
9 . The UE of claim 1 , wherein, to receive the command, the one or more processors are individually or collectively operable to execute the code to cause the UE to: receive the command that indicates a quantity of the one or more resources.
10 . The UE of claim 1 , wherein a quantity of the one or more resources is based at least in part on a frequency range associated with the target cell, a status of the target cell, or a combination thereof.
11 . The UE of claim 1 , wherein, to receive the command, the one or more processors are individually or collectively operable to execute the code to cause the UE to: receive the command that triggers a cell switch procedure or a physical random access channel procedure.
12 . The UE of claim 1 , wherein, to receive the control signal, the one or more processors are individually or collectively operable to execute the code to cause the UE to: receive the control signal that indicates a plurality of periodic resources associated with periodic reference signals, wherein the aperiodic reference signal is associated with a single quasi co location (QCL) associated with the periodic reference signals.
13 . A method for wireless communications by a user equipment (UE), comprising: receiving, from a serving cell, a control signal indicating a set of parameters for a target cell available for handover for the UE and indicating the target cell is configured to transmit an aperiodic reference signal during a handover procedure; receiving, from the serving cell, a command that identifies the target cell for a handover from the serving cell, wherein the command indicates one or more resources associated with the aperiodic reference signal; receiving, from the target cell, the aperiodic reference signal over the one or more resources; and transmitting, based at least in part on the aperiodic reference signal, a random access message based at least in part on time information or frequency information obtained from the aperiodic reference signal.
14 . The method of claim 13 , wherein receiving the aperiodic reference signal comprises: receiving the aperiodic reference signal in accordance with a configuration, indicated by the set of parameters, for the one or more resources.
15 . The method of claim 14 , wherein the configuration of the one or more resources comprises a time domain configuration indicating the one or more resources as a time duration after reception of the command, wherein receiving the aperiodic reference signal comprises: receiving the aperiodic reference signal after the time duration.
16 . The method of claim 14 , wherein the configuration indicates a quantity of the one or more resources.
17 . The method of claim 14 , wherein the one or more resources comprise a plurality of subsets of resources including first subset of resources and a second subset of resources separated by a time gap.
18 . The method of claim 13 , wherein receiving the command comprises: receiving the command that indicates an identification associated with the one or more resources.
19 . The method of claim 13 , wherein receiving the command comprises: receiving the command that indicates the one or more resources associated with the aperiodic reference signal as a time duration after reception of the command, wherein receiving the aperiodic reference signal comprises: receiving the aperiodic reference signal after the time duration.
20 . A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by one or more processors to: receive, from a serving cell, a control signal indicating a set of parameters for a target cell available for handover and indicating the target cell is configured to transmit an aperiodic reference signal during a handover procedure; receive, from the serving cell, a command that identifies the target cell for a handover from the serving cell, wherein the command indicates one or more resources associated with the aperiodic reference signal; receive, from the target cell, the aperiodic reference signal over the one or more resources; and transmit, based at least in part on the aperiodic reference signal, a random access message based at least in part on time information or frequency information obtained from the aperiodic reference signal.

Description

FIELD OF TECHNOLOGY The following relates to wireless communications, including techniques for cell handover using aperiodic channel state information reference signals. BACKGROUND Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth 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 communications system may include one or more base stations, each supporting wireless communication for communication devices, which may be known as user equipment (UE). SUMMARY The systems, methods, and devices of this disclosure each have several innovative aspects, no single one of which is solely responsible for the desirable attributes disclosed herein. A method for wireless communications by a user equipment (UE) is described. The method may include receiving, from a serving cell, a control signal indicating a set of parameters for a target cell available for handover for the UE and indicating the target cell is configured to transmit an aperiodic reference signal during a handover procedure, receiving, from the serving cell, a command that identifies the target cell for a handover from the serving cell, where the command indicates one or more resources associated with the aperiodic reference signal, receiving, from the target cell, the aperiodic reference signal over the one or more resources, and transmitting, based on the aperiodic reference signal, a random access message based on time information or frequency information obtained from the aperiodic reference signal. A UE for wireless communications is described. The UE may include one or more memories storing processor executable code, and one or more processors coupled with the one or more memories. The one or more processors may individually or collectively be operable to execute the code to cause the UE to receive, from a serving cell, a control signal indicating a set of parameters for a target cell available for handover for the UE and indicating the target cell is configured to transmit an aperiodic reference signal during a handover procedure, receive, from the serving cell, a command that identifies the target cell for a handover from the serving cell, where the command indicates one or more resources associated with the aperiodic reference signal, receive, from the target cell, the aperiodic reference signal over the one or more resources, and transmit, based on the aperiodic reference signal, a random access message based on time information or frequency information obtained from the aperiodic reference signal. Another UE for wireless communications is described. The UE may include means for receiving, from a serving cell, a control signal indicating a set of parameters for a target cell available for handover for the UE and indicating the target cell is configured to transmit an aperiodic reference signal during a handover procedure, means for receiving, from the serving cell, a command that identifies the target cell for a handover from the serving cell, where the command indicates one or more resources associated with the aperiodic reference signal, means for receiving, from the target cell, the aperiodic reference signal over the one or more resources, and means for transmitting, based on the aperiodic reference signal, a random access message based on time information or frequency information obtained from the aperiodic reference signal. A non-transitory computer-readable medium storing code for wireless communications is described. The code may include instructions executable by one or more processors to receive, from a serving cell, a control signal indicating a set of parameters for a target cell available for handover for the UE and indicating the target cell is configured to transmit an aperiodic reference signal during a handover procedure, receive, from the serving cell, a command that identifies the target cell for a handover from the serving cell, where the command indicates one or more resources associated with the aperiodic reference signal, receive, from the target cell, the aperiodic reference signal over the one or more resources, and transmit, based on the aperiodic reference signal, a random access message based on time information or frequency information ob