Apparatus, method, and computer program

Abstract

A method, apparatus, and computer program are provided for causing user equipment to receive, from a first network node, first information activating an identifier associated with a target network node; determining to transmit random access channel signaling using a configuration corresponding to the identifier associated with the target network node; and transmitting the random access channel signaling.

Description

[Technical Field]

[0001] The examples described herein relate generally to apparatus, methods, and computer programs, and more particularly (but not exclusively) to apparatus, methods, and computer programs for apparatus. [Background technology]

[0002] A communication system may be considered a facility that enables a communication session between two or more entities, such as communication devices, base stations, and / or other nodes, by providing a carrier between the various entities necessarily involved in the communication path.

[0003] The communication system may be a wireless communication system. Examples of wireless systems include public land mobile networks (PLMNs) operating according to radio standards such as those provided by 3GPP, satellite-based communication systems, and various wireless local networks, e.g., wireless local area networks (WLANs). Wireless systems may typically be divided into cells and are therefore often referred to as cellular systems.

[0004] Communication systems and associated devices typically operate according to a given standard or specification that sets out what various entities associated with the system are allowed to do and how that should be accomplished. The communication protocols and / or parameters to be used for the connection are also typically defined. An example of a standard is the so-called 5G standard. Summary of the Invention [Means for solving the problem]

[0005] According to a first aspect, there is provided a method for a user equipment, the method comprising: receiving, from a first network node, first information activating an identifier associated with a target network node; determining to transmit random access channel signaling using a configuration corresponding to the identifier associated with the target network node; and transmitting the random access channel signaling.

[0006] The determining may include: monitoring for an instruction from the first network node to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target network node for a first predetermined time period; and determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node when no instruction is received during the first predetermined time period.

[0007] The determining may include: determining that uplink transmission timing for transmitting an uplink transmission to a target network node is misaligned with respect to reception of the uplink transmission at the target network node; and in response to determining the misalignment, determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node.

[0008] The determining to transmit may be made in response to determining that timing alignment adjustments made by the user equipment cannot correct the misalignment.

[0009] The receiving may include: a handover command; and the determining may include: in response to determining that the handover command relates to a physical cell identifier different from a physical cell identifier associated with the first network node, determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with a target network node.

[0010] The method may include: receiving a random access response to the random access channel signaling from the target network node during a second predetermined time period; and configuring uplink and / or downlink communications with the target network node using spatial information associated with an identifier associated with the target network node in response to the received random access.

[0011] The method may include: monitoring for receipt of a random access response to the random access channel signaling from the target network node during a second predetermined time period; and following expiration of the second predetermined time period without a random access response being received, configuring uplink and / or downlink communications with the target network node using spatial information associated with an identifier associated with the target network node.

[0012] The handover command may include a conditional handover command.

[0013] Determining may include: identifying that an identifier associated with the target network node has been activated by receiving spatial information and / or power control parameters associated with the identifier associated with the target network node.

[0014] The method may include: receiving, via at least one of downlink control information, and / or a medium access control control element, and / or a configuration for Sounding Reference Signal signaling, spatial information and / or power control parameters associated with an identifier associated with the target network node.

[0015] The method may include: identifying spatial information associated with an identifier associated with a target network node; and configuring uplink and / or downlink communications with the target network node using the spatial information.

[0016] The method may include: receiving, from at least one of the first network node and the target network node, a calculated timing advance configuration to apply to transmissions made to the target network node; and transmitting to the target network node after applying the received calculated timing advance configuration.

[0017] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a Timing Advance Group identifier, a control resource set pool index, a transmit-receive point identifier, at least one Transmission Configuration Indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0018] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0019] The first network node may include at least one of the target network node or a network node different from the target network node.

[0020] According to a second aspect, there is provided a method for a system, the system including: a user equipment configured to perform any of the methods according to the first aspect; a first network node; and a target network node, the method further including: receiving, at the target network node, random access channel signaling from the user equipment subsequent to the user equipment receiving the first information activating an identifier associated with the target network node; calculating, at at least one of the first network node and the target network node, a timing advance configuration to be applied by the user equipment to transmissions made by the user equipment to the target transmission reception point; and causing, by at least one of the first network node and the target network node, the calculated timing advance configuration to be signaled to the user equipment to modify a transmission time of the transmission made to the target transmission reception point.

[0021] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0022] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0023] The first network node may include at least one of the target network node or a network node different from the target network node.

[0024] According to a third aspect, there is provided an apparatus for user equipment, comprising: means for receiving first information from a first network node and a target network node, the first information activating an identifier associated with the target network node; means for determining to transmit random access channel signaling using a configuration corresponding to the identifier associated with the target network node; and means for transmitting the random access channel signaling.

[0025] The means for determining may comprise means for monitoring for instructions from the first network node and / or the target network node to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target network node for a first predetermined time period; and means for determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node when no instructions are received during the first predetermined time period.

[0026] The means for determining may comprise: means for determining that uplink transmission timing for transmitting an uplink transmission to a target network node is misaligned with respect to reception of the uplink transmission at the target network node; and means for determining, in response to determining the misalignment, to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node.

[0027] The means for determining to transmit may be performed in response to determining that timing alignment adjustments made by the user equipment cannot correct the misalignment.

[0028] The means for receiving may include means for receiving a handover command, and the means for determining may comprise: means for determining, in response to determining that the handover command relates to a physical cell identifier different from a physical cell identifier associated with the first network node, to transmit the random access channel signaling using a configuration corresponding to an identifier associated with a target network node.

[0029] The apparatus may comprise: means for receiving a random access response to random access channel signaling from a target network node during a second predetermined time period; and means for configuring uplink and / or downlink communication with the target network node using spatial information associated with an identifier associated with the target network node in response to the received random access.

[0030] The apparatus may comprise: means for monitoring for arrival of a random access response to the random access channel signaling from the target network node during a second predetermined time period; and means for configuring uplink and / or downlink communications with the target network node using spatial information associated with an identifier associated with the target network node following expiration of the second predetermined time period without a random access response being received.

[0031] The handover command may include a conditional handover command.

[0032] The means for determining may comprise: means for identifying that the identifier associated with the target network node has been activated by receiving spatial information and / or power control parameters associated with the identifier associated with the target network node.

[0033] The apparatus may comprise means for receiving, by at least one of: downlink control information, and / or a medium access control control element, and / or a configuration for sounding reference signal signaling, spatial information and / or power control parameters associated with an identifier associated with the target network node.

[0034] The apparatus may comprise: means for identifying spatial information associated with an identifier associated with a target network node; and means for configuring uplink and / or downlink communications to the target network node using the spatial information.

[0035] The apparatus may comprise: means for receiving, from at least one of the first network node and the target network node, a calculated timing advance configuration to apply to transmissions made to the target network node; and means for transmitting to the target network node after applying the received calculated timing advance configuration.

[0036] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0037] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0038] The first network node may include at least one of the target network node or a network node different from the target network node.

[0039] According to a fourth aspect, there is provided a system comprising: a user equipment according to any of the third aspect; a first network node; and a target network node, wherein the target network node comprises means for random access channel signaling from the user equipment following the user equipment receiving the first information activating an identifier associated with the target network node, at least one of the first network node and the target network node comprises means for calculating a timing advance configuration to be applied by the user equipment to transmissions made by the user equipment to a target transmission reception point, and at least one of the first network node and the target network node comprises means for causing the calculated timing advance configuration to be signaled to the user equipment to alter transmission times of transmissions made to the target transmission reception point.

[0040] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0041] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0042] The first network node may include at least one of the target network node or a network node different from the target network node.

[0043] According to a fifth aspect, there is provided an apparatus for user equipment, comprising: at least one processor; and at least one memory containing code that, when executed by the at least one processor, causes the apparatus to: receive, from a first network node, first information that activates an identifier associated with a target network node; determine to transmit random access channel signaling using a configuration corresponding to the identifier associated with the target network node; and transmit the random access channel signaling.

[0044] The determining may include: monitoring for an instruction from the first network node and / or the target network node to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target network node for a first predetermined time period; and determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node when no instruction is received during the first predetermined time period.

[0045] The determining may include: determining that uplink transmission timing for transmitting an uplink transmission to a target network node is misaligned with respect to reception of the uplink transmission at the target network node; and in response to determining the misalignment, determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node.

[0046] The determining to transmit may be made in response to determining that timing alignment adjustments made by the user equipment cannot correct the misalignment.

[0047] The receiving may include receiving a handover command, and the determining may include: determining, in response to determining that the handover command relates to a physical cell identifier different from a physical cell identifier associated with the first network node, to transmit the random access channel signaling using a configuration corresponding to an identifier associated with a target network node.

[0048] The apparatus may be configured to: receive, from the target network node, a random access response to the random access channel signaling during a second predetermined time period; and, in response to the received random access, configure uplink and / or downlink communications with the target network node using spatial information associated with an identifier associated with the target network node.

[0049] The device may be caused to monitor for an arrival of a random access response to the random access channel signaling from the target network node during a second predetermined time period; and following expiration of the second predetermined time period without a random access response being received, may be caused to configure uplink and / or downlink communications with the target network node using spatial information associated with an identifier associated with the target network node.

[0050] The handover command may include a conditional handover command.

[0051] Determining may include: identifying that an identifier associated with the target network node has been activated by receiving spatial information and / or power control parameters associated with the identifier associated with the target network node.

[0052] The device may be caused to receive spatial information and / or power control parameters associated with an identifier associated with the target network node by at least one of: downlink control information, and / or a medium access control control element, and / or a configuration for sounding reference signal signaling.

[0053] The device may be caused to: identify spatial information associated with an identifier associated with a target network node; and use the spatial information to configure uplink and / or downlink communications with the target network node.

[0054] The apparatus may be caused to: receive, from at least one of the first network node and the target network node, a calculated timing advance configuration to apply to transmissions made to the target network node; and, after applying the received calculated timing advance configuration, transmit to the target network node.

[0055] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0056] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0057] The first network node may include at least one of the target network node or a network node different from the target network node.

[0058] According to a sixth aspect, there is provided a system comprising: a user equipment according to any of the fifth aspect; a first network node; and a target network node, wherein each of the first network node and the target network node comprises: at least one respective processor and at least one respective memory containing code, wherein the respective code associated with the target network node, when executed by the at least one processor of each of the target network nodes, causes a target transmission reception point to receive random access channel signaling from the user equipment subsequent to the user equipment receiving the first information activating an identifier associated with the target network node; and causes at least one of the first network node and the target network node, by its respective stored code executing on its respective processor, to calculate a timing advance configuration to be applied by the user equipment to transmissions made by the user equipment to the target transmission reception point, and to signal the calculated timing advance configuration to the user equipment to modify a transmission time of the transmission made to the target transmission reception point.

[0059] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0060] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0061] The first network node may include at least one of the target network node or a network node different from the target network node.

[0062] According to a seventh aspect, there is provided an apparatus for user equipment, comprising: a receiving circuit for receiving, from a first network node, first information activating an identifier associated with a target network node; a determining circuit for determining to transmit random access channel signaling using a configuration corresponding to the identifier associated with the target network node; and a transmitting circuit for transmitting the random access channel signaling.

[0063] The decision circuit for making the decision may comprise: a monitoring circuit for monitoring for an instruction from the first network node and / or the target network node to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target network node for a first predetermined time period; and a decision circuit for determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node when no instruction is received during the first predetermined time period.

[0064] The determination circuit for making a determination may comprise: a determination circuit for determining that an uplink transmission timing for transmitting an uplink transmission to a target network node is misaligned with respect to reception of the uplink transmission at the target network node; and a determination circuit for determining, in response to determining the misalignment, to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node.

[0065] The decision circuitry for deciding to transmit may be made in response to determining that timing alignment adjustments made by user equipment cannot correct the misalignment.

[0066] The receiving circuitry for receiving may include receiving circuitry for receiving a handover command, and the determining circuitry for determining may comprise: a determining circuit for determining, in response to determining that the handover command relates to a physical cell identifier different from a physical cell identifier associated with the first network node, to transmit the random access channel signaling using a configuration corresponding to an identifier associated with a target network node.

[0067] The apparatus may comprise a receiving circuit for receiving a random access response to the random access channel signaling from the target network node during a second predetermined time period, and a using circuit for configuring uplink and / or downlink communications with the target network node using spatial information associated with an identifier associated with the target network node in response to the received random access.

[0068] The apparatus may comprise: a monitoring circuit for monitoring for arrival of a random access response to the random access channel signaling from the target network node during a second predetermined time period; and a using circuit for configuring uplink and / or downlink communications to the target network node using spatial information associated with an identifier associated with the target network node following expiration of the second predetermined time period without a random access response being received.

[0069] The handover command may include a conditional handover command.

[0070] The determination circuit for determining may include: an identification circuit for identifying that the identifier associated with the target network node has been activated by receiving spatial information and / or power control parameters associated with the identifier associated with the target network node.

[0071] The apparatus may comprise: a receiving circuit for receiving, by at least one of downlink control information, and / or a medium access control control element, and / or a configuration for sounding reference signal signaling, spatial information and / or power control parameters associated with an identifier associated with the target network node.

[0072] The apparatus may include: an identification circuit for identifying spatial information associated with an identifier associated with a target network node; and a usage circuit for using the spatial information to configure uplink and / or downlink communications with the target network node.

[0073] The apparatus may include: a receiving circuit for receiving, from at least one of the first network node and the target network node, a calculated timing advance configuration to apply to a transmission made to the target network node; and a transmitting circuit for transmitting to the target network node after applying the received calculated timing advance configuration.

[0074] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0075] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0076] The first network node may include at least one of the target network node or a network node different from the target network node.

[0077] According to an eighth aspect, there is provided a system comprising: a user equipment according to any of the seventh aspect; a first network node; and a target network node, wherein the target network node comprises receiving circuitry for receiving random access channel signaling from the user equipment following the user equipment receiving the first information activating an identifier associated with the target network node, and at least one of the first network node and the target network node comprises: calculating circuitry for calculating a timing advance configuration to be applied by the user equipment to transmissions made by the user equipment to the target transmission reception point, and at least one of the first network node and the target network node comprises causing circuitry for causing the calculated timing advance configuration to be signaled to the user equipment to alter transmission times of transmissions made to the target transmission reception point.

[0078] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0079] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0080] The first network node may include at least one of the target network node or a network node different from the target network node.

[0081] According to a ninth aspect, there is provided a non-transitory computer-readable medium comprising program instructions to cause an apparatus for user equipment to: receive, from a first network node, first information activating an identifier associated with a target network node; determine to transmit random access channel signaling using a configuration corresponding to the identifier associated with the target network node; and transmit the random access channel signaling.

[0082] The determining may include: monitoring for an instruction from the first network node and / or the target network node to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target network node for a first predetermined time period; and determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node when no instruction is received during the first predetermined time period.

[0083] The determining may include: determining that uplink transmission timing for transmitting an uplink transmission to a target network node is misaligned with respect to reception of the uplink transmission at the target network node; and in response to determining the misalignment, determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target network node.

[0084] The determining to transmit may be made in response to determining that timing alignment adjustments made by the user equipment cannot correct the misalignment.

[0085] The receiving may include receiving a handover command, and the determining may include: determining, in response to determining that the handover command relates to a physical cell identifier different from a physical cell identifier associated with the first network node, to transmit the random access channel signaling using a configuration corresponding to an identifier associated with a target network node.

[0086] The apparatus may be configured to: receive, from the target network node, a random access response to the random access channel signaling during a second predetermined time period; and, in response to the received random access, configure uplink and / or downlink communications with the target network node using spatial information associated with an identifier associated with the target network node.

[0087] The device may be caused to: monitor for arrival of a random access response to the random access channel signaling from the target network node during a second predetermined time period; and, following expiration of the second predetermined time period without a random access response being received, configure uplink and / or downlink communications with the target network node using spatial information associated with an identifier associated with the target network node.

[0088] The handover command may include a conditional handover command.

[0089] Determining may include: identifying that an identifier associated with the target network node has been activated by receiving spatial information and / or power control parameters associated with the identifier associated with the target network node.

[0090] The device may be caused to receive spatial information and / or power control parameters associated with an identifier associated with the target network node by at least one of: downlink control information, and / or a medium access control control element, and / or a configuration for sounding reference signal signaling.

[0091] The device may be caused to: identify spatial information associated with an identifier associated with a target network node; and use the spatial information to configure uplink and / or downlink communications to the target network node.

[0092] The apparatus may be caused to: receive, from at least one of the first network node and the target network node, a calculated timing advance configuration to apply to transmissions made to the target network node; and, after applying the received calculated timing advance configuration, transmit to the target network node.

[0093] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0094] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0095] The first network node may include at least one of the target network node or a network node different from the target network node.

[0096] According to a tenth aspect, there is provided a system including: a user equipment according to any of the ninth aspect; a first network node; and a target network node, wherein respective non-transitory computer-readable media including program instructions for each of the target network node and the first network node are provided, wherein the respective non-transitory computer-readable medium including program instructions associated with the target network node causes the target transmission reception point to receive random access channel signaling from the user equipment subsequent to the user equipment receiving the first information activating an identifier associated with the target network node; and the respective non-transitory computer-readable medium including program instructions causes at least one of the first network node and the target network node to calculate a timing advance configuration to be applied by the user equipment to transmissions made by the user equipment to the target transmission reception point, and to signal the calculated timing advance configuration to the user equipment to alter the transmission time of the transmission made to the target transmission reception point.

[0097] The identifier associated with the target network node may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource set pool index, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0098] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of the target network node; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0099] The first network node may include at least one of the target network node or a network node different from the target network node.

[0100] According to an eleventh aspect, there is provided a computer program product stored on a medium capable of causing an apparatus to perform any of the methods as described herein.

[0101] According to a twelfth aspect, there is provided an electronic device, which may comprise an apparatus as described herein.

[0102] According to a thirteenth aspect, there is provided a chipset, which may comprise an apparatus as described herein.

[0103] According to a fourteenth aspect, there is provided a method comprising: receiving, from a first network node, an indication indicating information associated with a transmission associated with a second network node; determining to transmit RACH signaling using a random access channel, a RACH configuration, corresponding to the information associated with the transmission associated with the second network node; and transmitting the RACH signaling to the second network node.

[0104] The information associated with the transmission may include at least one of: spatially related information for at least one uplink channel transmission, power control parameter set information, an identifier of the second network node, a sounding reference signal resource indicator (SRI), spatially related information update for the SRI, or a transmission configuration indicator (TCI) state.

[0105] The identifier of the second network node may include one of: a physical cell identifier, a control resource set, CORESET, a pool index, and a transmission reception point identifier, TRP ID.

[0106] The at least one uplink channel transmission may include: a transmission on a physical uplink shared channel and / or a transmission on a physical uplink control channel.

[0107] The method may further include: determining, based on receipt of information associated with the transmission, that the identifier of the second network node is active.

[0108] The indication may be sent by a downlink control information (DCI), a medium access control control element (MAC CE), and / or a handover command message.

[0109] According to a fifteenth aspect, there is provided an apparatus, comprising: means for receiving an indication from a first network node indicating information associated with a transmission associated with a second network node; means for determining to transmit RACH signaling using a random access channel, a RACH configuration corresponding to the information associated with the transmission associated with the second network node; and means for transmitting the RACH signaling to the second network node.

[0110] The information associated with the transmission may include at least one of: spatially related information for at least one uplink channel transmission, power control parameter set information, an identifier of the second network node, a sounding reference signal resource indicator (SRI), spatially related information update for the SRI, or a transmission configuration indicator (TCI) state.

[0111] The identifier of the second network node may include one of: a physical cell identifier, a control resource set, CORESET, a pool index, and a transmission reception point identifier, TRP ID.

[0112] The at least one uplink channel transmission may include a transmission on a physical uplink shared channel and / or a transmission on a physical uplink control channel.

[0113] The apparatus further includes means for determining, based on receipt of the information associated with the transmission, that the identifier of the second network node is active.

[0114] The indication may be sent by a downlink control information (DCI), a medium access control control element (MAC CE), and / or a handover command message.

[0115] According to a sixteenth aspect, there is provided an apparatus comprising: at least one processor; and at least one memory containing code, which, when executed by the at least one processor, causes the apparatus to: receive an indication from a first network node indicating information associated with a transmission associated with a second network node; determine to transmit RACH signaling using a random access channel, a RACH configuration corresponding to the information associated with the transmission associated with the second network node; and cause the second network node to transmit the RACH signaling.

[0116] The information associated with the transmission may include at least one of: spatially related information for at least one uplink channel transmission, power control parameter set information, an identifier of the second network node; a sounding reference signal resource indicator (SRI), spatially related information update for the SRI, or a transmission configuration indicator (TCI) state.

[0117] The identifier of the second network node may include one of: a physical cell identifier, a control resource set, CORESET, a pool index, and a transmission reception point identifier, TRP ID.

[0118] The at least one uplink channel transmission may include a transmission on a physical uplink shared channel and / or a transmission on a physical uplink control channel.

[0119] The apparatus may further be caused to determine, based on receipt of information associated with the transmission, that the identifier of the second network node is active.

[0120] The indication may be sent by a downlink control information (DCI), a medium access control control element (MAC CE), and / or a handover command message.

[0121] According to a seventeenth aspect, there is provided an apparatus comprising: a receiving circuit for receiving an indication from a first network node indicating information associated with a transmission associated with a second network node; a deciding circuit for deciding to transmit RACH signaling using a random access channel, a RACH configuration corresponding to the information associated with the transmission associated with the second network node; and a transmitting circuit for transmitting the RACH signaling to the second network node.

[0122] The information associated with the transmission may include at least one of: spatially related information for at least one uplink channel transmission, power control parameter set information, an identifier of the second network node, a sounding reference signal resource indicator (SRI), spatially related information update for the SRI, or a transmission configuration indicator (TCI) state.

[0123] The identifier of the second network node may include one of: a physical cell identifier, a control resource set, CORESET, a pool index, and a transmission reception point identifier, TRP ID.

[0124] The at least one uplink channel transmission may include a transmission on a physical uplink shared channel and / or a transmission on a physical uplink control channel.

[0125] The apparatus further includes a determination circuit for determining, based on receipt of the information associated with the transmission, that the identifier of the second network node is active.

[0126] The indication may be sent by a downlink control information (DCI), a medium access control control element (MAC CE), and / or a handover command message.

[0127] According to an eighteenth aspect, there is provided a non-transitory computer-readable medium comprising program instructions to cause an apparatus to: receive an indication from a first network node indicating information associated with a transmission associated with a second network node; determine to transmit RACH signaling using a random access channel, a RACH configuration, corresponding to the information associated with the transmission associated with the second network node; and transmit the RACH signaling to the second network node.

[0128] The information associated with the transmission may include at least one of: spatially related information for at least one uplink channel transmission, power control parameter set information, an identifier of the second network node; a sounding reference signal resource indicator (SRI), spatially related information update for the SRI, or a transmission configuration indicator (TCI) state.

[0129] The identifier of the second network node may include one of: a physical cell identifier, a control resource set, CORESET, a pool index, and a transmission reception point identifier, TRP ID.

[0130] The at least one uplink channel transmission may include a transmission on a physical uplink shared channel and / or a transmission on a physical uplink control channel.

[0131] The apparatus may further be caused to determine, based on receipt of information associated with the transmission, that the identifier of the second network node is active.

[0132] The indication may be sent by a downlink control information (DCI), a medium access control control element (MAC CE), and / or a handover command message.

[0133] Some examples will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0134] [Figure 1A] FIG. 1 illustrates a schematic representation of a 5G system. [Figure 1B] FIG. 1 illustrates a schematic representation of a 5G system. [Figure 2] FIG. 1 shows a schematic representation of a network device. [Figure 3] FIG. 1 shows a schematic representation of a user equipment. [Figure 4]FIG. 1 illustrates a schematic representation of a non-volatile memory medium that stores instructions that, when executed by a processor, enable the processor to perform one or more of several example methodologies. [Figure 5] FIG. 1 shows a schematic representation of a network. [Figure 6] FIG. 1 is a diagram illustrating Timing Advance. [Figure 7] 1 is a diagram illustrating example signaling between entities described herein. [Figure 8] FIG. 1 illustrates example operations that may be performed by user equipment described herein. [Figure 9] 10A-10C illustrate example operations that may be performed by the devices described herein. [Figure 10] 10A-10C illustrate example operations that may be performed by the devices described herein. DETAILED DESCRIPTION OF THE INVENTION

[0135] Before describing the examples in detail, some general principles of 5G wireless communication systems will be briefly explained with reference to Figures 1A and 1B.

[0136] 1A shows a schematic representation of a 5G system (5GS) 100. The 5GS may include a user equipment (UE) 102 (which may also be referred to as a communication device or terminal), a 5G access network (AN) (which may be a 5G radio access network (RAN) or any other type of 5G AN, such as a Non-3GPP Interworking Function (N3IWF) / Trusted Non-3GPP Gateway Function (TNGF) for untrusted / trusted non-3GPP access or a Wireline Access Gateway Function (W-AGF) for wireline access) 104, a 5G core (5GC) 106, one or more application functions (AFs) 108, and one or more data networks (DNs) 110.

[0137] The 5G RAN may include one or more gNodeB (gNB) distributed unit functions connected to one or more gNB unit functions. The RAN may include one or more access nodes.

[0138] The 5GC 106 may include one or more Access and Mobility Management Functions (AMFs) 112, one or more Session Management Functions (SMFs) 114, one or more Authentication Server Functions (AUSFs) 116, one or more Unified Data Management (UDM) Functions 118, one or more User Plane Functions (UPFs) 120, one or more Unified Data Repository (UDR) Functions 122, one or more Network Repository Functions (NRFs) 128, and / or one or more Network Exposure Functions (NEFs) 124. The role of the NEFs is to provide secure exposure of network services (e.g., voice, data connectivity, billing, subscriber data, etc.) towards third parties. The NRF 128 is not depicted with its interfaces, although it is understood that this is for reasons of clarity and that the NRF 128 may have multiple interfaces with other network functions.

[0139] The 5GC 106 also includes a network data analytics function (NWDAF) 126. The NWDAF is responsible for providing network analytics information based on requests from one or more network functions or devices in the network. A network function may also subscribe to the NWDAF 126 to receive information therefrom. Thus, the NWDAF 126 is also configured to receive and store network information from one or more network functions or devices in the network. Data collection by the NWDAF 126 may be based on at least one subscription to events provided by at least one network function.

[0140] The network may further include a management data analytics service (MDAS) producer or MDAS Management Service (MnS) producer. The MDAS MnS producer may provide data analytics in the management plane, taking into account parameters including, for example, load levels and / or resource utilization. For example, an MDAS MnS producer for a network function (NF) may collect performance data related to the load of the NF, such as the resource usage status of the NF. Analysis of the collected data may result in a prediction of resource usage information for a predefined future time window. This analysis may also recommend appropriate actions, such as resource scaling, admission control, traffic load balancing, etc.

[0141] Figure 1B shows a schematic representation of 5GC as expressed in current 3GPP specifications. This architecture is intended to illustrate potential components that may be included in a core network, it being understood that the principles currently described are not limited to core networks comprising only the components described.

[0142] 1B shows a 5G Core 106' that includes a UPF 120' connected to an SMF 114' over an N4 interface. The SMF 114' is connected to each of the UDM 122', NEF 124', NWDAF 126', AF 108', Policy Control Function (PCF) 130', AMF 112', and Charging Function 132', and to each other over an interconnection medium connecting these network functions. The 5G Core 106' further includes a Network Repository Function (NRF) 133' and a Network Function 134', which connect to the interconnection medium.

[0143] The concept and functionality of NR timing advance are the same as LTE timing advance. Simply put, timing advance is a special command (notification) from a transmitting / receiving point (e.g., an access point such as an eNB / gNB) to a UE to configure the UE to adjust its uplink transmission (uplink frame) with respect to its downlink reception timing (downlink frame). This type of uplink adjustment applies to any of a variety of uplink channels, such as the Physical Uplink Shared Channel (PUSCH), the Physical Uplink Control Channel (PUCCH), and the Sounding Reference Signal (SRS). Incidentally, SRS is an uplink-only, UE-specific signal transmitted by the UE to help the access point acquire channel state information (CSI) for each user.

[0144] Generally, timing advance is a mechanism used (usually by a medium access control (MAC) control element) to control uplink signal transmission timing. The access point continuously measures the time difference between PUSCH / PUCCH / SRS reception at the access point and the subframe time, and may send a "timing advance" command to the UE to change the uplink transmission timing so that it is better aligned with the subframe timing on the network side. When the PUSCH / PUCCH / SRS transmission timer arrives at the network too early, the access point sends a timing advance command to the UE to instruct the UE to send its uplink signal a little later. When the PUSCH / PUCCH / SRS transmission timer arrives at the network too late, the access point sends a timing advance command to the UE to instruct the UE to send its uplink signal a little earlier.

[0145] The timing advance is illustrated with respect to FIG.

[0146] 6 illustrates a downlink frame 601, the reception of which is offset from the start of the transmission of an uplink frame 602 by a time T, where T is: T=(N TA +N TAOffset )T c It can be written as:

[0147] N TA represents the timing advance value received from the network (e.g., by a Medium Access Control (MAC) control element (CE) and / or by Random Access Response (RAR) signaling). TA can be defined in several different ways. For example, the MAC CE Timing Advance value is: N TA-New =N TA-Old +(T A -31)*16.64 / 2 M (However, T A =0, 1, 2, …, 63) It can be defined as:

[0148] As another example, the RAR timing advance value is: N TA =T A *16.64 / 2 μ (However, T A = 0, 1, 2, …, 3846) It can be defined as:

[0149] T c is a predefined timing unit (T in the current specification) c =0.509ns).

[0150] N TAOffsetis identified by the UE based on information received from the network or (if the network has not provided a specific value) according to a default value. This default value may depend on the currently used frequency range (e.g., FR1 or FR2), whether the uplink transmission is made using frequency division duplex (FDD) or time division duplex (TDD) techniques, and whether the transmission is made with or without LTE-NR coexistence. These default values ​​are illustrated below with respect to Table 1.

[0151] [Table 1]

[0152] This type of uplink timing advance adjustment applies to several different channels, such as the physical uplink shared channel (PUSCH), the physical uplink control channel (PUCCH), and the sounding reference signal (SRS).

[0153] As mentioned above, the timing advance information may be provided to the UE through random access response (RAR) signaling or by MAC CE signaling.

[0154] When RAR signaling is used, the UE calculates the timing advance value to be used from information contained in two different MAC layer commands. For the first uplink message after Physical Random Access Channel (PRACH) signaling, the UE applies the timing advance value it extracts from the received RAR signaling. After the initial RACH process, the UE may apply the timing advance value it extracts from the Timing Advance MAC CE, if received.

[0155] When MAC CE signaling is used, the UE adjusts its UL transmission based on the MAC CE-Timing Advance received after the initial attach procedure. The Timing Advance Command Field is 6 bits, which means that the actual timing can range from -32 to 32T. c This means that a total of 64 timing advance steps can be signaled, ranging from 0.509 to 16.3 μs. Since Tc is 0.509 according to the current specification, the physical timing range for MAC CE-based timing advance is -16.3 μs to 16.3 μs, with a 15 kHz subcarrier spacing.

[0156] A timing advance group includes a set of one or more serving cells with the same uplink timing advance and the same downlink timing reference cell. Each timing advance group includes at least one serving cell with a configured uplink, and the mapping of each serving cell to a timing advance group is configured by radio resource control (RRC) signaling. 3GPP TS 38.321 defines a timing advance group as a group of serving cells configured by RRC and that group of serving cells that use the same timing reference cell and the same timing advance value for cells with configured uplinks. A timing advance group that includes a MAC entity's Secondary Primary Cell (SpCell) is called a Primary Timing Advance Group (P Timing Advance Group), while the term Secondary Timing Advance Group (S Timing Advance Group) refers to other timing advance groups.

[0157] Rel-17 introduced and specified the use of inter-cell Multi-Transmit-Receive-Point (Multi-TRP) operation in 3GPP networks.

[0158] Multi-TRP is a feature that allows an access point, such as a gNB, to use more than one TRP to communicate with a UE. There are several different ways for this type of communication to take place.

[0159] For example, the first TRP and the second TRP may transmit data to the UE using different Physical Downlink Shared Channels (PDSCHs), while control signals for the two PDSCHs are transmitted only by the first TRP (e.g., by a Physical Downlink Control Channel (PDCCH transmission or by a Downlink Control Information (DCI) transmission). In this case, if there is any problem with the radio link between the UE and the first TRP, such as PDCCH reception failing, the UE's communication over the second TRP will be affected as well.

[0160] As another example, a first TRP and a second TRP may transmit data to a UE using different physical downlink shared channels (PDSCHs), while also transmitting their own control information for these PDSCHs (e.g., via respective PDCCH or DCI transmissions). In this case, if there is any problem in the radio link with one of the TRPs, communication with the other TRP may remain unimpaired.

[0161] As a third example, the first and second TRPs are jointly used to process downlink and uplink signals (similar scenario with coordinated multipoint (CoMP) transmission).

[0162] Under the Multi-TRP definition provided by Rel-17, a Transmission Configuration Indicator (TCI) state may be associated with either one or two Physical Cell Identities (PCIs), or may otherwise correspond to those PCIs.

[0163] The PCI is an identifier used to identify a cell during the cell selection procedure. According to the current definition (which may be subject to change), the PCI has a value that depends on the combination of the cell's Primary Synchronization Signal (PSS) and the cell's Secondary Synchronization Signal (SSS).

[0164] The TCI state is dynamically sent from the network to the UE. The TCI state may be signaled using a downlink control information (DCI) message, which includes a configuration such as a quasi-colocated relationship between downlink reference signals in one Channel State Indicator Reference Signal (CSI-RS) set and a PDSCH Demodulation reference signal port. Two antenna ports are said to be quasi-colocated when the characteristics of the channel through which symbols on one antenna port are carried can be inferred from the channel through which symbols on the other antenna port are carried. Therefore, indicating the TCI state to the UE may indicate to the UE a quasi-colocated relationship between a PDSCH demodulation reference signal and at least one downlink reference signal.

[0165] Rel-17 specifies that for inter-cell Multi-TRP, one PCI associated with one or more activated TCI states for the Physical Downlink Shared Channel / Physical Downlink Control Channel (PDSCH / PDCCH) will be associated with one set of resources (e.g., with one CORESETPoolIndex), and another PCI associated with one or more activated TCI states for the PDSCH / PDCCH will be associated with another set of resources (e.g., with another CORESETPoolIndex). Activated TCI states can be considered as TCI states that are included in a restricted subset of the total number of TCI states (i.e., fewer than all possible TCI states), where the restricted subset is configured by the medium access control control element commands for a given channel and / or signal and / or transmission. CORESETPoolIndex is the index of the CORESET pool for the corresponding CORESET. CORESET refers to the control resource set, which refers to a set of resources. For example, in the frequency domain, a CORESET is a set of contiguous or distributed physical resource blocks (PRBs), while in the time domain, a CORESET is a set of contiguous Orthogonal Frequency Division Multiplex (OFDMA) symbols.

[0166] The association between PCI and CORESETPoolIndex when switching between intra-cell multi-TRP and inter-cell multi-TRP was determined to be for future study.

[0167] Rel-18 introduced several goals related to multiple-input multiple-output (MIMO) enhancements, including the use of two timing advances for signaling in uplink multiple DCI for use in multiple TRPs.

[0168] Some of these goals are as follows:

[0169] First, using the Rel-17 TCI framework described above, it was decided to extend the Rel-17 Unified TCI framework for indication of multiple downlink and uplink TCI states with emphasis on multi-TRP use cases.

[0170] Second, it was decided to investigate the use of a larger number of orthogonal Demodulation Reference Signal (DMRS) ports for downlink and uplink multi-user MIMO (without increasing DM-RS overhead) for Cyclic Prefix (CP)-OFDM transmissions. This investigation will consider both the use of up to 24 orthogonal DM-RS ports and / or the aim of a common design between downlink and uplink DMRS transmissions, where the maximum number of orthogonal ports for each applicable DMRS type is doubled for both single- and double-symbol DMRS.

[0171] Third, it was decided to investigate uplink DMRS, SRS, and SRS Resource Indicator (SRI), and precoding information enhancements (including codebooks) to enable up to eight transmitter uplink operation supporting more than four layers per UE in the uplink, targeting a range of different application scenarios (e.g., vehicles / industrial devices, etc.).

[0172] Fourth, it was decided to investigate simultaneous multi-panel uplink transmission for higher uplink throughput / reliability, focusing on Frequency Range 2 (FR2) and multi-TRP, assuming up to two TRPs and up to two panels, targeting a range of different application scenarios (e.g., vehicles / industrial devices, etc.).

[0173] This study will include investigating uplink precoding indications for use on PUSCH, considering single DCI and multi-DCI based multi-TRP operation, no new codebooks are introduced for multi-panel simultaneous transmission, and the total number of layers is up to 4 across all panels and the total number of codewords is up to 2 across all panels.

[0174] This study will further include the use of uplink beam indication for transmission along PUCCH and / or PUSCH, considering single DCI and multi-DCI based multi-TRP operation. For the multi-DCI based multi-TRP operation case, only PUSCH+PUSCH or PUCCH+PUCCH are transmitted across two panels on the same component carrier (CC).

[0175] Fifth, research may be conducted to consider the use of two timing advances for uplink multi-DCI for multi-TRP operation and to consider power control for uplink single DCI for multi-TRP operation.

[0176] General support for two timing advance enhancements is provided in Rel-18 and beyond for both intra-cell and inter-cell multi-DCI multi-TRP scenarios.

[0177] The following concerns addressing issues that may arise when seeking to support the use of two timing advance enhancements for both intra-cell and inter-cell multi-DCI multi-TRP scenarios, in other words, the following concerns addressing issues that arise with respect to the fifth goal stated above.

[0178] The following aims to address the issues associated with obtaining / determining timing advance for inter-cell multi-TRP without necessarily increasing the current level of downlink control overhead.

[0179] As mentioned above, Rel-17 defined inter-cell M-TRP operation. According to this definition, a TCI state can be associated with a PCI, and at most two PCIs can be associated with an activated TCI state. It should be noted that the associated PCI of the serving cell cannot be explicitly associated with a TCI state; only additional PCIs, i.e., PCIs other than the serving cell PCI, can be explicitly associated with a TCI state. This explicit association of the additional PCI can be done, for example, through a synchronization signal (e.g., a synchronization signal block (SSB) and / or a CSI-RS) associated with the additional PCI.

[0180] To address at least one of the above-mentioned problems, the following discloses a mechanism under which a UE autonomously sends a RACH (or PRACH) transmission based on a preconfigured random access configuration. A network-based entity (e.g., a serving TRP and / or a target TRP and / or their controllers) may subsequently use the arrival of such random access channel transmissions at the target TRP to calculate a timing advance configuration for the UE for transmissions to the target TRP. This timing advance configuration may be provided back to the UE, which may then apply the calculated timing advance configuration for subsequent transmissions from the UE to the target TRP.

[0181] Because the random access channel transmissions made by the UE are made autonomously, the UE does not receive a trigger from the network specifically to cause the random access channel transmission to occur, thereby reducing the amount of overhead signaling in the network compared to the case when an explicit command is received.

[0182] The pre-configured random access configuration may be, for example, contention based random access (CBRA) and / or contention free random access (CFRA).

[0183] A RACH / PRACH transmission may be sent for a cell / TRP with a given PCI (different from the PCI of the UE's serving cell) when the given PCI is activated. The UE may then use a pre-configured random access configuration, such as a RACH occasion and / or preamble and / or a PUSCH occasion (for a 2-step RACH), that corresponds to the activated PCI for the RACH transmission.

[0184] More details regarding when a UE may perform autonomous signaling are provided below, but in general, a UE may perform autonomous signaling in response to determining that a cell / TRP associated with a PCI different from the PCI associated with the UE's serving cell / TRP has been activated.

[0185] The UE may determine whether the PCI is activated in any of several different ways, which are discussed further below.

[0186] The UE may consider a PCI to be active or activated when the UE determines that at least one of the following information has been signaled to the UE:

[0187] Activation or indication in a MAC control element of spatial relationship information for at least one PUCCH resource, where this spatial relationship information indicates the Reference Signal (RS) associated with the PCI being considered. The association may be signaled to the UE using higher layer signaling (i.e., above MAC layer signaling). In the current specification, the spatial relationship information is indicated using the "PUCCH-SpatialRelationInfo" control element.

[0188] Activation or indication in a MAC control element of power control parameter set information for at least one PUCCH resource, where this power control parameter set information is associated with the PCI under consideration. The power control information sets the power for the UE transmitting uplink signals. The association can be signaled to the UE using higher layer signaling (i.e., above MAC layer signaling).

[0189] Indication, e.g. by the MAC Control element, of spatial relationship information update for the SRI, where this spatial relationship information is associated with the PCI being considered. The association can be signaled to the UE using higher layer signaling (i.e. above MAC layer signaling).

[0190] · Downlink Control Information (DCI) of the SRI of the PUSCH, an indication included in the DCI for which spatial relationship information or quasi-co-location information is associated with the PCI under consideration.

[0191] Indication of spatial relationship information for the SRS, where this spatial relationship information is associated with the PCI being considered. The association can be signaled to the UE using higher layer signaling (i.e., above MAC layer signaling).

[0192] Indication of MAC CE and / or downlink control information activating and / or indicating at least one TCI state for downlink and / or uplink channels / signals, where this at least one TCI state indicates quasi-co-location information containing reference signals associated with the PCI under consideration. The association can be signaled to the UE using higher layer signaling (i.e., above MAC layer signaling).

[0193] In an example application, when a cell associated with a PCI under consideration represents or is configured with multiple TRPs (e.g., multiple TRPs share the same given PCI), the UE may autonomously send a RACH transmission when that PCI and TCI state / TRP identity / or different uplink transmission is activated (or indicated) for the UE based on a random access configuration corresponding to the considered PCI and TCI state, TRP identity (e.g., CORESETpoolIndex or TRP ID, etc.), or other representation of a different uplink link / transmission. The association of CORESETPoolIndex and / or TRP ID to a PCI state may be configured using higher layer signaling (e.g., by RRC configuration signaling / signaling above the MAC layer).

[0194] In another example application, a RACH transmission towards a different Cell / TRP may be triggered by the reception of a PDCCH signal received from a (newly) activated PCI (e.g., a PDCCH order from or pointing to the activated PCI).

[0195] In such a case, the UE may send a RACH transmission based on a random access configuration corresponding to an activated PCI when the UE has not received a PDCCH (or PDCCH order) from the activated PCI within a predefined / preconfigured time duration (e.g., the time after the PCI is activated).

[0196] Furthermore, when the UE receives a PDCCH (or a PDCCH order) from an activated PCI within a predefined / preconfigured time duration (e.g., a time after the PCI is activated), the UE may send a RACH transmission based on the indicated / preconfigured random access configuration corresponding to the activated PCI.

[0197] The above-mentioned time durations may be configured or defined with respect to a reference point / time, such as the first or last symbol of an uplink transmission (e.g., a transmission on a Physical Uplink Control Channel (PUCCH) or a transmission on a Physical Uplink Shared Channel (PUSCH)) or a downlink reception (e.g., a transmission on a Physical Downlink Control Channel (PDCCH) or a transmission on a Physical Downlink Shared Channel (PDSCH)).

[0198] For example, the reference point / time may be the last symbol of a PUCCH transmitted in response to a PDSCH carrying a MAC CE that activates the PCI. As another example, the reference point / time may be the last symbol of a PUCCH transmitted in response to a PDCCH carrying downlink control information that activates the PCI.

[0199] In an example, a Random Access Channel (RACH) transmission toward (or corresponding to) a different Cell / TRP may be triggered by receiving a handover command associated with a given PCI other than the serving cell PCI. When such a handover command is received, the UE may send a RACH transmission based on a random access configuration corresponding to the given PCI.

[0200] When the UE receives a RACH response (or a positive RACH response) from the network (e.g., a Random Access Response (RAR) from a different Cell / TRP), the UE may consider the RACH response as a PCI activation command to enable the UE to receive PDCCH / PDSCH and / or transmit PUCCH / PUSCH / SRS using the TCI state associated with the given PCI. In other words, the UE may consider the RACH response as an indication that the TCI state associated with the given PCI may be considered activated / indicated.

[0201] When the UE does not receive a random access response (or does not correctly receive a random access response (RAR) from the network), the UE may still receive a PDCCH / PDSCH and transmit a PUCCH / PUSCH using the TCI state associated with a given PCI after a predefined / preconfigured time duration. The time duration may be configured or defined with respect to a reference point / time, such as the first or last symbol of a RACH transmission.

[0202] In the case of a conditional handover (CHO) handover, a RACH transmission toward (or corresponding to) a different Cell / TRP may be triggered by a conditional handover triggered by a UE associated with or otherwise corresponding to a given PCI other than the PCI associated with the serving cell. When such a conditional handover event occurs, the UE may send a RACH transmission to the target cell based on a random access configuration corresponding to the given PCI.

[0203] The UE may be configured to use and / or apply one or more of the above operations via signaling from the network, for example, the UE may be configured to use and / or apply one or more of the above operations via RRC signaling from the network.

[0204] The currently described mechanism can be used by the network to obtain / determine / calculate an updated timing advance of the TRP in a cell with an activated PCI.

[0205] These exemplary operations are illustrated in more detail below.

[0206] FIG. 7 illustrates example signaling that may occur between the entities described herein.

[0207] 7 illustrates signaling that may take place between a UE 701, a first transmission / reception point TRP1 702, and a second transmission / reception point TRP2 703. The first transmission / reception point 702 is associated with a first PCI, PCI1. The second transmission / reception point 703 is associated with a second PCI, PCI2. In other words, the first and second transmission / reception points 702, 703 belong to different physical cells.

[0208] During 7001, the network (e.g., the first TRP, AP, or gNB) configures the UE with a random access configuration for the second PCI. This random access configuration may include RACH resources and / or RACH preambles (and / or even PUSCH occasions) for the second PCI. The random access configuration may be performed using RRC signaling. The random access configuration may be performed using an entity located in the access point / gNB. For example, the random access configuration may be signaled from a central unit to the UE 701. The entity configuring the UE with the random access configuration may be at least one of the first transmit / receive point, the second transmit / receive point, and / or a controller of at least one of the first and / or second transmit / receive points.

[0209] During 7002, the first transmitting / receiving point 702 signals to the UE 701. This signaling may include an indication of at least one TCI state. In this example, the indication of the at least one TCI state includes an indication of a TCI state corresponding to a second PCI. The indicated TCI state provides quasi-co-location information including a reference signal corresponding to or otherwise associated with the second PCI. The quasi-co-location information may be inferred using previously received signaling from a network that provides such association. This association information is currently provided by higher layer signaling (i.e., above the MAC layer) in Rel-17.

[0210] The indication may include an instruction to activate at least one indicated TCI state.

[0211] The signaling of 7002 may be performed in any number of ways. For example, the signaling of 7002 may be achieved by the first transmit / receive point 702 sending a MAC control element. As another example, the signaling of 7002 may be achieved by the first transmit / receive point 702 sending downlink control information. The MAC control element and / or the downlink control information may be signaled using a physical downlink channel, such as a PDSCH or a PDCCH.

[0212] During 7003, the UE 701 determines that a second PCI is activated based on the received signaling of 7002. For example, the UE 701 may determine that a second PCI is newly activated based on the received MAC CE / DCI, and specifically, the indicated TCI state, because a TCI state is associated with or otherwise corresponds to the second PCI.

[0213] In response to this determination of 7003, the UE then decides / determines to transmit on the random access channel using the random access configuration for the second PCI.

[0214] Therefore, during 7004, the UE 701 signals a RACH preamble (or PRACH) using the random access configuration for the second PCI. This signaling in 7004 is subsequently received by the second transmission / reception point 703.

[0215] During 7005, the first and / or second transmit / receive point (or some other network entity (not shown) that controls at least one of these first and / or second transmit / receive points) uses the received RACH transmission of 7004 to determine a timing advance corresponding to the second transmit / receive point 703 and / or the second PCI.

[0216] For example, the second TRP 703 may calculate a timing advance associated with the second PCI based on the RACH reception. Details of how this is done in the TRP are described later in this specification.

[0217] As one example, the second TRP 703 may determine a time difference between the time the RACH transmission of 7004 is received and the downlink transmission timing used by the TRP. This determined time difference may later be used to calculate a one-way propagation delay from the UE 701 to the second TRP 703. The calculation may occur when any network entity, such as the first TRP 702, the second TRP 703, and / or any controller thereof, provides the determined time difference. The calculated one-way propagation delay may be used when determining an uplink timing shift. For example, the uplink timing shift may be twice the propagation delay. The uplink timing shift indicates a timing offset that the second TRP 703 should apply in order to receive the uplink transmission from the UE 701 at the desired uplink receive timing at the second TRP 703. The uplink timing shift may correspond to a timing advance indicated toward the UE 701.

[0218] FIG. 8 illustrates some additional features of the presently described mechanism from the perspective of a UE (such as UE 701 of FIG. 7).

[0219] During 801, the UE determines that a given PCI is activated. This may be, for example, as a result of the signaling of 7002.

[0220] During 802, the UE determines that the UE has not received a PDCCH order that triggers the UE to make a RACH transmission corresponding to the given PCI within a preconfigured time period for determining that the given PCI is activated.

[0221] During 803, in response to the determination of 802, the UE makes a RACH transmission using the RACH configuration corresponding to the given PCI. This transmission may be as follows:

[0222] 9 and 10 illustrate aspects of the above example. It is therefore understood that the features described above may find correspondence below. Furthermore, it is understood that the above-described examples may provide additional features for understanding how the presently described examples may be implemented, and without limiting the same.

[0223] Furthermore, although the following refers to "transmit-receive points," these entities may simply be thought of as network nodes. Network nodes may include access points to the network, TRPs, and gNBs, among others. Network nodes may include controllers of access points to the network.

[0224] FIG. 9 illustrates operations that may be performed by user equipment.

[0225] During 901, the user equipment receives first information from at least one of the first transmit-receive point and the target transmit-receive point, activating an identifier associated with the target transmit-receive point. The first transmit-receive point may include a serving transmit-receive point of the user equipment or a non-serving transmit-receive point of the user equipment. The phrase “associated with” may be used herein to indicate that a configured association exists between two entities. For example, when an identifier is associated with the target transmit-receive point, a configured association exists that associates the identifier with the target transmit-receive point. Alternatively, the phrase “associated with” may not necessarily mean that a configured (explicit) association exists. For example, when an identifier is associated with the target transmit-receive point (or network node), the identifier is essentially used to represent the target transmit-receive point (or network node).

[0226] The identifier may be preconfigured in the UE. For example, the identifier may be preconfigured in the UE using RRC signaling. The identifier may be preconfigured in the UE as part of a set of identifiers for identifying the target TRP. The first information activating the identifier may be received by MAC and / or physical layer signaling. The first information activating the identifier may be received by a MAC control element and / or by downlink control information signaling.

[0227] During 902, the UE autonomously decides to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target transmission-reception point. In this context, the term “autonomously” includes the UE taking an action (i.e., deciding to transmit) without explicit instructions to do so from the network (e.g., the first TRP and / or the target TRP).

[0228] During 903, the UE transmits the random access channel signaling.

[0229] Autonomously determining may include: monitoring for instructions from the first transmit-receive point and / or the target transmit-receive point for a first predetermined time period to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target transmit-receive point; and determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target transmit-receive point when no instructions are received during the first predetermined time period.

[0230] Autonomously determining may include: determining that an uplink transmission timing for transmitting an uplink transmission to a target transmit-receive point is misaligned with respect to reception of the uplink transmission at the target transmit-receive point; and in response to determining the misalignment, determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with the target transmit-receive point.

[0231] The deciding to transmit may be made in response to determining that autonomous timing alignment adjustment by the user equipment cannot correct the misalignment. For example, in response to detecting a misalignment, the UE may apply a timing adjustment to the timing of an uplink transmission to the first TRP to correct the misalignment without receiving an explicit command from the network to make such an adjustment. The deciding to transmit may be made in response to a subsequent determination that the adjustment did not correct the misalignment sufficiently for the uplink transmission to the first TRP to be successful. As another example, the UE may determine that the misalignment is relatively large, e.g., greater than a threshold, in which case the UE may determine that autonomous timing alignment adjustment cannot correct the misalignment. The UE may then decide to transmit RACH signaling in this case. On the other hand, the UE may determine that the misalignment is relatively small, e.g., less than (or equal to) a threshold, in which case the UE may determine that an autonomous timing alignment adjustment can correct this misalignment. The UE may then decide not to transmit RACH signaling in this case.

[0232] The receiving may include a handover command, and the autonomously determining may include: determining to transmit the random access channel signaling using a configuration corresponding to an identifier associated with a target transmitting-receiving point in response to determining that the handover command relates to a physical cell identifier different from a physical cell identifier associated with the first transmitting-receiving point.

[0233] The user equipment may further: receive a random access response to the random access channel signaling from the target transmit-receive point during a second predetermined time period; and in response to the received random access, configure uplink and / or downlink communication with the target transmit-receive point using spatial information associated with an identifier associated with the target transmit-receive point, where the spatial information may include at least one of: a TCI state, a spatial relationship, an SRS resource indicator, an SRS resource, or a power control parameter set.

[0234] The UE: monitors for the arrival of a random access response to the random access channel signaling from the target transmit-receive point during a second predetermined time period; and following expiration of the second predetermined time period without a random access response being received, may configure uplink and / or downlink communications with the target transmit-receive point using spatial information associated with an identifier associated with the target transmit-receive point.

[0235] The handover command may include a conditional handover command.

[0236] Autonomously determining may include: identifying that an identifier associated with the target transmit-receive point has been activated by receiving spatial information and / or power control parameters associated with the identifier associated with the target transmit-receive point.

[0237] The UE may receive spatial information and / or power control parameters associated with an identifier associated with the target transmit-receive point via at least one of downlink control information, and / or a medium access control control element, and / or a configuration for sounding reference signal signaling.

[0238] The user equipment: identifies spatial information associated with an identifier associated with the target transmit-receive point; and may use the spatial information to configure uplink and / or downlink communication with the target transmit-receive point. The spatial information may be pre-configured in the UE using higher layer signaling. For example, the spatial information may be pre-configured in the UE using RRC signaling.

[0239] The user equipment may: receive, from at least one of the first transmit-receive point and the target transmit-receive point, a calculated timing advance configuration to apply to transmissions made to the target transmit-receive point; and transmit to the target transmit-receive point after applying the received calculated timing advance configuration. The timing advance configuration may have been calculated using the transmitted random access signaling of 903.

[0240] FIG. 10 illustrates features of a system including a user equipment according to FIG. 9, a first TRP as described with respect to FIG. 9, and a target TRP as described with respect to FIG.

[0241] During 1001, a target transmission-reception point receives random access channel signaling from a user equipment subsequent to the user equipment receiving the first information activating an identifier associated with the target transmission-reception point.

[0242] During 1002, at least one of the first transmit-receive point and the target transmit-receive point calculates a timing advance configuration to be applied by the user equipment to transmissions made by the user equipment to the target transmit-receive point.

[0243] During 1003, at least one of the first transmit-receive point and the target transmit-receive point causes the calculated timing advance configuration to be signaled to the user equipment to modify the transmission time of a transmission made to the target transmit-receive point. Although not shown in FIG. 10, the user equipment may use the received calculated timing advance configuration to adjust the uplink timing of a transmission to the target TRP.

[0244] In all of the above examples of Figures 9 and 10, the identifier associated with the target transmitting-receiving point may include at least one of: a physical cell identity identifier, a timing advance group identifier, a control resource (coreset) pool index, a transmitting-receiving point identifier, at least one transmission configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0245] The first information may include at least one of: information related to at least one uplink channel or space for transmission; power control parameter set information; an identifier of a target TRP; a sounding reference signal resource indicator; information updates related to space for the sounding reference signal resource indicator; and / or a transmission configuration indicator status.

[0246] Although the present mechanism is described in the context of handover, the present mechanism may be applied to any operation involving a UE and two separate transmission / reception points. For example, the presently described mechanism may also be configured for carrier aggregation (CA). In other words, the presently described operation may be configured / applicable per component carrier (or group of component carriers).

[0247] It is further understood that references throughout to "RACH" transmissions also cover PRACH transmissions. For example, preamble transmissions in the case of a 4-step RACH, and preamble and PUSCH transmissions in the case of a 2-step RACH. The term "RACH transmission" may also refer to any subsequent message transmitted by the UE to the second transmission / reception point after making a determination that the second PCI is active. For example, using current terminology, a PUCCH transmission corresponding to Msg3(PUSCH) or Msg4 may be used for signaling 7004.

[0248] The mechanism described above provides a technique for obtaining / determining timing advance for a newly activated cell or PCI in inter-cell multi-TRP cases that does not increase downlink control signaling overhead compared to current signaling mechanisms.

[0249] It is understood that the terms "activated" and "active" are used interchangeably above.

[0250] Furthermore, while the above examples have focused on PCI, it is understood that the presently described techniques may also be applied in relation to a UE detecting other identifiers corresponding to (or otherwise associated with) a TRP. Identifiers associated with a TRP may include one or more of the following: a PCI, a timing advance group (TAG) identifier, an index into a set of control resources, a transmit-receive point identifier, at least one transmit configuration indicator state, at least one spatial relationship identifier, and / or at least one power control parameter set configuration.

[0251] For example, a TAG may be considered active if at least one TCI state or spatial relationship information or power control parameter set associated with this TAG is activated or otherwise indicated to the UE, which may be indicated to the UE by, for example, a MAC control element and / or by downlink control information.

[0252] Furthermore, when a TAG is activated, the UE may decide to autonomously transmit the RACH using the RACH configuration corresponding to this TAG, in a similar manner as proposed above, when the UE detects that the PCI for the TRP is active.

[0253] As another example, when a new TCI state is updated / indicated to the UE, an indication, which when the UE detects that the PCI for the TRP is active, may trigger the UE to autonomously transmit a RACH using the RACH configuration corresponding to this TCI state, in a similar manner as proposed above.

[0254] As yet another example, a set of TCI states may be configured, and when at least one of these TCI states is indicated to the UE as being activated, this may trigger the UE to autonomously transmit a RACH using the RACH configuration corresponding to this set of TCI states, in a similar manner as proposed above, when the UE detects that the PCI for the TRP is active.

[0255] FIG. 2 illustrates an example of a controller for a communication system, which may be coupled to and / or for controlling, for example, a RAN node, e.g., a base station, a station of an access system such as a gNB, a central unit of a cloud architecture, or a node of a core network such as an MME or S-GW, a scheduling entity such as a spectrum management entity, or a device hosting a server or host, e.g., an NRF, an NWDAF, an AMF, an SMF, a UDM / UDR, etc. The controller may be integrated with a node or module of the core network or RAN, or may be external to those nodes or modules. In some examples, a base station includes a separate controller unit or module. In other examples, the controller may be another network element, such as a radio network controller or a spectrum controller. The controller 200 may be configured to provide control over communications in a service area of ​​the system. The device 200 comprises at least one memory 201, at least one data processing unit 202, 203, and an input / output interface 204. Via the interface, the controller may be coupled to a receiver and a transmitter of the device. The receiver and / or transmitter may be implemented as a radio front end or a remote radio head. For example, the controller 200 or processor 201 may be configured to execute appropriate software code to provide the control functionality.

[0256] Possible wireless communication devices will now be described in more detail with reference to FIG. 3, which shows a schematic, partially cross-sectional view of a communication device 300. Such communication devices are often referred to as user equipment (UE) or terminal. A suitable mobile communication device may be any device capable of transmitting and receiving radio signals. Non-limiting examples include a mobile station (MS) or mobile device, such as a mobile phone or "smartphone," a computer equipped with a wireless interface card or other wireless interface facility (e.g., a USB dongle), a personal digital assistant (PDA) or tablet equipped with wireless communication capabilities, or any combination thereof, or the like. Mobile communication devices may provide data communications to carry communications such as voice, electronic mail (email), text messages, multimedia, etc. A user may thus be provided with and be offered numerous services by means of their communication device. Non-limiting examples of these services include two-way or multi-way calls, data communication or multimedia services, or simply access to a data communication network system such as the Internet. Users may also be provided with broadcast or multicast data. Non-limiting examples of content include downloads, television and radio programs, videos, advertisements, various alerts, and other information.

[0257] The wireless communication device may be, for example, a mobile device, i.e., a device that is not fixed to a particular location, or the wireless communication device may be a stationary device. The wireless device may or may not require human interaction for communication. As described herein, the term UE or "user" is used to refer to any type of wireless communication device.

[0258] The wireless device 300 may receive signals over the air or radio interface 307 via appropriate equipment for receiving and may transmit signals via appropriate equipment for transmitting radio signals. In Figure 3, a transceiver unit is shown schematically by block 306. The transceiver unit 306 may be implemented, for example, by a radio portion and an associated antenna arrangement. The antenna arrangement may be internal or external to the wireless device.

[0259] A wireless device is typically provided with at least one data processing entity 301, at least one memory 302, and possibly other components 303 for use in the software- and hardware-assisted execution of the tasks the wireless device is designed to perform, including controlling access to and communication with access systems and other communication devices. Data processing, storage, and other associated control may be provided on a suitable circuit board and / or within a chipset. This feature is represented by reference numeral 304. A user may control the operation of the wireless device by a suitable user interface, such as a keypad 305, voice commands, a touch-sensitive screen or pad, a combination thereof, or the like. A display 308, a speaker, and a microphone may also be provided. Furthermore, the wireless communication device may include appropriate connectors (either wired or wireless) to other devices and / or for connecting external accessories, such as hands-free equipment, to the wireless communication device.

[0260] FIG. 4 shows schematic representations of non-volatile memory media 400a (e.g., a computer disk (CD) or digital versatile disk (DVD)) and 400b (e.g., a universal serial bus (USB) memory stick) that store instructions and / or parameters 402 that, when executed by a processor, enable the processor to perform one or more of the steps of the method of FIG. 9 and / or FIG. 10 and / or methods otherwise previously described.

[0261] As provided herein, various aspects are described in the detailed description of examples and in the claims. Generally, some examples may be implemented in hardware or special purpose circuits, software, logic, or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software that may be executed by, for example, but not limited to, a controller, microprocessor, or other computing device. While various examples may be illustrated and described as block diagrams, flowcharts, or using some other graphical representation, it is well understood that the blocks, apparatus, systems, techniques, or methods described herein may be implemented in, for example, but not limited to, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller, or other computing device, or any combination thereof.

[0262] Examples may be implemented by computer software stored in memory and executable by at least one data processor of the participating entities, by hardware, or by a combination of software and hardware. Furthermore, in this regard, it should be noted that any procedure, e.g., in Figures 9 and / or 10 and / or as otherwise previously described, may represent program steps, or interconnected logic circuits, blocks, and functions, or a combination of program steps and logic circuits, blocks, and functions. Software may be stored on physical media, such as memory chips or memory blocks embodied in a processor, magnetic media (such as hard disks or floppy disks), and optical media (e.g., DVDs and their data variants, CDs, etc.).

[0263] The memory may be of any type suitable for the local technology environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory. The data processor may be of any type suitable for the local technology environment and may include, by way of non-limiting examples, one or more of a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a gate-level circuit, and a processor based on a multi-core processor architecture.

[0264] Additionally or alternatively, some examples may be implemented using circuitry configured to perform one or more of the previously described functions and / or method steps, which may be provided in a base station, a communication device, and / or a core network entity.

[0265] As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) a hardware-only circuit implementation (such as an implementation in purely analog and / or digital circuitry); (b) A combination of hardware circuitry and software, such as: (i) a combination of analog and / or digital hardware circuitry with software / firmware; and (ii) any portion of a hardware processor, software, and memory along with software (including a digital signal processor), that cooperates to cause an apparatus, such as a communications device or base station, to perform the various functions previously described; and (c) A hardware circuit and / or processor, such as a microprocessor or portion of a microprocessor, that requires software (e.g., firmware) to operate, although software may not be present when it is not required for operation.

[0266] This definition of circuit applies to all uses of the term in this application, including in any claims. As a further example, as used in this application, the term circuit also covers solely a hardware circuit or processor (or processors), or a portion of a hardware circuit or processor, as well as its (or their) accompanying software and / or firmware implementations. The term circuit also covers, for example, integrated devices.

[0267] The foregoing description has provided a complete and informative description of several examples, by way of non-limiting example. However, various modifications and adaptations will become apparent to those skilled in the relevant art in view of the foregoing description, when read in conjunction with the accompanying drawings and claims. However, all such and similar modifications of the teachings will still fall within the scope of the claims.

[0268] In the above, various examples are described using radio access architectures based on Long Term Evolution Advanced (LTE-Advanced, LTE-A) or New Radio (NR, 5G) as examples of access architectures to which the described techniques can be applied, without limiting the examples to such architectures. The examples may also be applied to other types of communication networks having suitable means by appropriately adjusting parameters and procedures. Some examples of other options for suitable systems are universal mobile telecommunications system (UMTS) radio access network (UTRAN), wireless local area network (WLAN or WiFi), worldwide interoperability for microwave access (WiMAX), Bluetooth®, personal communications services (PCS), ZigBee®, wideband code division multiple access (WCDMA), systems using ultra-wideband (UWB) technology, sensor networks, mobile ad hoc networks (MANET), and Internet Protocol Multimedia Subsystem (IMS), or any combination thereof.

[0269] 5 depicts a simplified example of a system architecture that merely shows some elements and functional entities that are all logical units, and the implementation of those elements and functional entities may differ from those shown. The connections shown in FIG. 5 are logical connections, and the actual physical connections may differ. It will be apparent to those skilled in the art that a system typically also includes functions and structures other than those shown in FIG. 5.

[0270] However, the example is not limited to the system given as an example, and a person skilled in the art can apply the solution to other communication systems provided with the required characteristics.

[0271] The example of Figure 5 shows portions of an exemplary radio access network. For example, the radio access network may support sidelink communications, which are described in more detail below.

[0272] 5 shows devices 500 and 502. Devices 500 and 502 are configured to wirelessly connect over one or more communication channels with node 504. Node 504 is further connected to a core network 506. In one example, node 504 may be an access node, such as an (e / g) Node B, serving devices within a cell. In one example, node 504 may be a non-3GPP access node. The physical link from a device to an (e / g) Node B is referred to as an uplink or reverse link, and the physical link from an (e / g) Node B to a device is referred to as a downlink or forward link. It should be understood that the (e / g) Node B or their functionality may be implemented using any node, host, server, access point, or other entity suitable for such use.

[0273] A communication system typically includes more than one (e / g)Node B, in which case the (e / g)Node Bs may also be configured to communicate with each other by wired or wireless links designed for that purpose. These links may be used for signaling purposes. An (e / g)Node B is a computing device configured to control the radio resources of the communication system to which the (e / g)Node B is coupled. A Node B may also be referred to as any other type of interfacing device, including a base station, an access point, or a relay station, capable of operating in a wireless environment. An (e / g)Node B includes or is coupled to a transceiver. A connection is made from the transceiver of the (e / g)Node B to an antenna unit that establishes a bidirectional radio link to the device. The antenna unit may include multiple antennas or antenna elements. The (e / g)Node B is further connected to a core network 506 (CN or Next Generation Core NGC). Depending on the deployed technology, the (e / g) Node B is connected to a Serving and Packet Data Network Gateway (S-GW+P-GW) or User Plane Function (UPF) for routing and forwarding user data packets and for providing device connectivity to one or more external packet data networks, and to a Mobile Management Entity (MME) or Access Mobility Management Function (AMF) for controlling device access and mobility.

[0274] Examples of devices are subscriber units, user devices, user equipment (UE), user terminals, terminal devices, mobile stations, mobile devices, and the like.

[0275] A device typically refers to a mobile or stationary device (e.g., a portable or non-portable computing device), including a wireless mobile communication device that operates with or without a universal subscriber identification module (USIM), and includes, but is not limited to, the following types of devices: mobile phones, smartphones, personal digital assistants (PDAs), handsets, devices that use wireless modems (alarm or measurement devices, etc.), laptop and / or touchscreen computers, tablets, game consoles, notebooks, and multimedia devices. It should be understood that a device may also be almost exclusively an uplink-only device, an example of which is a camera or video camera that loads images or video clips onto a network. A device may also be a device capable of operating in an Internet of Things (IoT) network, a scenario in which objects are provided with the ability to transmit data across a network without the need for human-to-human or human-to-computer interaction, such as will be used in smart power grids and connected vehicles. A device may also utilize the cloud. In some applications, the device may include a user portable device with a wireless portion (such as a watch, earphones, or glasses) and the computation is performed in the cloud.

[0276] A device illustrates one type of apparatus to which resources over the air interface are allocated and assigned, and thus any feature described herein with respect to a device may be implemented by a corresponding apparatus, such as a relay node. An example of such a relay node is a Layer 3 repeater (self-backhauling repeater) toward a base station. The device (or, in some examples, a Layer 3 relay node) is configured to perform one or more of the user equipment functionalities.

[0277] The various techniques described herein may also be applied to cyber-physical systems (CPSs), systems of collaborative computational elements that control physical entities. CPSs may enable the realization and utilization of a large number of interconnected information and communication technology (ICT) devices (sensors, actuators, processors, microcontrollers, etc.) embedded in physical objects in various locations. Mobile cyber-physical systems, in which the physical systems in question have inherent mobility, are a subcategory of cyber-physical systems. Examples of mobile physical systems include mobile robotics and electronic devices carried by people or animals.

[0278] In addition, although the device is depicted as a single entity, various units, processors and / or memory units (not all of which are shown in FIG. 5) may be implemented.

[0279] 5G will enable the use of many more base stations or nodes than LTE (the so-called small cell concept), including multiple-input, multiple-output (MIMO) antennas, macro sites operating in conjunction with smaller stations, and various radio technologies depending on service needs, use cases, and / or available spectrum. 5G mobile communications will support a wide range of use cases and related applications, including video streaming, augmented reality, various methods of data sharing, and various methods of machine-type applications (such as (massive) machine-type communications (mMTC) including vehicle safety systems, various sensors, and real-time control). 5G is expected to have multiple air interfaces, e.g., below 6 GHz, above 24 GHz, centimeter-wave, and millimeter-wave, and will be able to integrate with existing legacy radio access technologies such as LTE. Integration with LTE may be realized, at least in the early stages, as a system in which macro coverage is provided by LTE and 5G air interface access comes from small cells through aggregation to LTE. In other words, 5G is planned to support both inter-RAT operability (such as LTE-5G) and inter-RI operability (operability between air interfaces such as below 6 GHz - cmWave, 6 GHz, or above 24 GHz - cmWave and mmWave). One of the concepts expected to be used in 5G networks is network slicing, where multiple independent and dedicated virtual sub-networks (network instances) can be created within the same infrastructure to run services with different requirements regarding latency, reliability, throughput, and mobility.

[0280] The LTE network architecture is fully distributed in the radio and fully centralized in the core network. Low latency applications and services in 5G require bringing content closer to the radio, which leads to local breakout and multi-access edge computing (MEC). 5G enables analytics and knowledge generation to occur at the source of the data. This approach requires leveraging resources that may not be continuously connected to the network, such as laptops, smartphones, tablets, and sensors. MEC provides a distributed computing environment for application and service hosting. It also has the ability to store and process content close to cellular subscribers for faster response times. Edge computing covers a wide range of technologies, including wireless sensor networks, mobile data acquisition, mobile signature analysis, collaborative distributed peer-to-peer ad-hoc networking and processing that can be categorized as local cloud / fog computing and grid / mesh computing, dew computing, mobile edge computing, cloudlets, distributed data storage and retrieval, autonomous self-healing networks, remote cloud services, augmented and virtual reality, data caching, Internet of Things (massive connectivity and / or latency critical), and critical communications (autonomous vehicles, road safety devices, real-time analytics, time-critical control, healthcare applications).

[0281] The communications system may also communicate with or use services provided by other networks 512, such as the public switched telephone network, or a VoIP network, or the Internet, or a private network. The communications network may also be able to support the use of cloud services; for example, at least a portion of the core network operations may be performed as cloud services (depicted in FIG. 5 by "cloud" 514). This may also be referred to as edge computing when performed away from the core network. The communications system may also include a central control entity, or the like, that provides facilities for various operators' networks to cooperate, for example, in spectrum sharing.

[0282] Edge computing technologies can be incorporated into the Radio Access Network (RAN) by utilizing Network Function Virtualization (NFV) and Software-Defined Networking (SDN). Using edge cloud technologies can mean that access node operations are performed at least in part in a server, host, or node that is operatively coupled to a remote radio head or base station that includes a radio portion. It is also possible that node operations can be distributed among multiple servers, nodes, or hosts. The application of a Cloud RAN architecture allows RAN real-time functions to be performed at or near a remote antenna site (in a distributed unit, DU 508) and non-real-time functions to be performed in a centralized manner (in a centralized unit, CU 510).

[0283] It should also be understood that the distribution of labor between core network operations and base station operations may be different from that of LTE or may even be non-existent. Some other technological advances that will likely be used are big data and all-IP, which may change the way networks are built and managed. 5G (or New Radio, NR) networks are designed to support multiple tiers, and edge computing servers may be located between the core and base stations or Node Bs (gNBs). One example of edge computing is MEC, defined by the European Telecommunications Standards Institute. It should be understood that MEC (and other edge computing protocols) may also be applied in 4G networks.

[0284] 5G may also use satellite communications to enhance or complement the coverage of 5G services, for example by providing backhauling. Possible use cases are providing service continuity for machine-to-machine (M2M) or Internet of Things (IoT) devices or for vehicle occupants, ensuring service availability for Mobile Broadband (MBB) or critical communications, and future rail, maritime, and aviation communications. Satellite communications may use geostationary Earth orbit (GEO) satellite systems, but also low Earth orbit (LEO) satellite systems, especially megaconstellations (systems in which hundreds of (micro)satellites are deployed). Each satellite in a megaconstellation may cover several satellite-enabled network entities, which create ground cells. Ground cells may be created by terrestrial relay nodes or by gNBs located on the ground or within the satellites.

[0285] The depicted system is merely an example of a portion of a radio access system; in practice, the system may include multiple (e / g) Node Bs, a device may access multiple radio cells, and the system may also include other devices, such as physical layer relay nodes or other network elements, etc. At least one of the (e / g) Node Bs may be a home (e / g) Node B. In addition, in the geographic area of ​​a wireless communication system, multiple radio cells, as well as multiple different types of radio cells, may be provided. A radio cell may be a macrocell (or umbrella cell), which is a large cell typically having a diameter of up to tens of kilometers, or a smaller cell, such as a micro, femto, or picocell. The (e / g) Node B in FIG. 5 may provide any type of these cells. A cellular radio system may be realized as a multi-layer network including several types of cells.

Claims

1. 1. A method for a user equipment, comprising: receiving, from a first network node, first information activating an identifier associated with the target network node; determining to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target network node; transmitting random access channel signaling; A method comprising:

2. To decide, monitoring for instructions from the first network node and / or the target network node to transmit random access channel signaling using a configuration corresponding to the identifier for a first predetermined time period; determining, when no instructions are received within a first predetermined time period, to transmit random access channel signaling using a configuration corresponding to the identifier; The method of claim 1 , comprising:

3. To decide, determining that an uplink transmission timing for transmitting an uplink transmission to a target network node is misaligned with respect to reception of the uplink transmission at the target network node; determining, in response to determining the mismatch, to transmit random access channel signaling using a configuration corresponding to the identifier node; The method of claim 1 , comprising:

4. 4. The method of claim 3, wherein the determining to transmit is made in response to determining that timing alignment adjustments made by the user equipment cannot correct the misalignment.

5. The receiving includes a handover command, and the determining includes: and in response to determining that the handover command relates to a physical cell identifier different from a physical cell identifier associated with the first network node, determining to transmit the random access channel signaling using a configuration corresponding to the identifier. The method of claim 1 , comprising:

6. The method is receiving a random access response to the random access channel signaling from the target network node during a second predetermined time period; In response to the received random access, configuring uplink and / or downlink communications with the target network node using spatial information associated with the identifier. The method of claim 5 , comprising:

7. The method is monitoring for an arrival of a random access response to the random access channel signaling from the target network node during a second predetermined time period; and configuring uplink and / or downlink communications with the target network node using spatial information associated with the identifier following expiration of a second predetermined time period without a random access response being received. The method of claim 5 , comprising:

8. To decide, Identifying that an identifier associated with the target network node has been activated by receiving spatial information and / or power control parameters associated with the identifier associated with the target network node.

8. The method of claim 1, comprising:

9. 9. The method of claim 8, wherein the method comprises receiving spatial information and / or power control parameters associated with an identifier associated with the target network node by at least one of downlink control information, and / or a medium access control control element, and / or a configuration for sounding reference signal signaling.

10. receiving, from a first network node, first information activating an identifier associated with the target network node; determining to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target network node; transmitting random access channel signaling; An apparatus comprising: means for performing

11. When executed by the device, the device: receiving, from a first network node, first information activating an identifier associated with the target network node; determining to transmit random access channel signaling using a configuration corresponding to an identifier associated with the target network node; transmitting random access channel signaling; A computer program containing instructions to perform the following:

12. at least one processor; and at least one memory that stores instructions, which when executed by the at least one processor, cause the apparatus to perform at least: receiving an indication from a first network node indicating information associated with a transmission associated with a second network node; determining to transmit RACH signaling using a random access channel, RACH configuration corresponding to information related to a transmission associated with the second network node; transmitting RACH signaling to a second network node; A device that performs the following.

13. The information associated with the transmission is information related to a space for at least one uplink channel transmission; power control parameter set information, an identifier of the second network node; Sounding Reference Signal Resource Indicator, SRI, Space-related information updates for SRI, or Transmit Configuration Indicator, TCI Status 13. The apparatus of claim 12, comprising at least one of:

14. an identifier of the second network node; Physical cell identifier, A control resource set, CORESET, a pool index, and Transmission Reception Point Identifier, TRP ID 14. The apparatus of claim 13, comprising one of:

15. 15. The apparatus of claim 12, wherein the at least one uplink channel transmission comprises a transmission on a physical uplink shared channel and / or a transmission on a physical uplink control channel.

16. determining that the identifier of the second network node is active based on receiving information associated with the transmission; 16. The apparatus of claim 12, further comprising:

17. The apparatus according to any one of claims 12 to 16, wherein the indication is transmitted by a Downlink Control Information, DCI, Medium Access Control control element, MAC CE, and / or a Handover Command message.

18. receiving an indication from a first network node indicating information associated with a transmission associated with a second network node; determining to transmit RACH signaling using a random access channel, RACH configuration corresponding to information related to a transmission associated with the second network node; transmitting RACH signaling to a second network node; A method comprising:

19. When executed by the device, the device: receiving an indication from a first network node indicating information associated with a transmission associated with a second network node; determining to transmit RACH signaling using a random access channel, RACH configuration corresponding to information related to a transmission associated with the second network node; transmitting RACH signaling to a second network node; A computer program containing instructions to perform the following:

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