Gradual frequency adjustment for dual-loop frequency control in non-terrestrial network
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine, after an update to a location or a velocity of the UE, a closed-loop frequency pre-compensation and an open-loop frequency pre-compensation. The UE may transmit, after the update to the location or the velocity of the UE, an uplink signal using a frequency pre-compensation that is based at least in part on the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation. Numerous other aspects are described.
1 . A user equipment (UE), comprising:
one or more memories; and
one or more processors, coupled to the one or more memories, configured to:
receive one or more frequency pre-compensation commands from a network node;
determine, after an update to a location or a velocity of the UE, a closed-loop frequency pre-compensation and an open-loop frequency pre-compensation, wherein:
the closed-loop frequency pre-compensation is determined based at least in part on the one or more frequency pre-compensation commands, and
the open-loop frequency pre-compensation is determined based at least in part on the update to the location or the velocity of the UE; and
transmit, after the update to the location or the velocity of the UE, an uplink signal using a frequency pre-compensation that is based at least in part on the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation.
2 . The UE of claim 1 ,
wherein the one or more processors, to determine the closed-loop frequency pre-compensation, are configured to reset the closed-loop frequency pre-compensation to zero.
3 . The UE of claim 2 ,
wherein the closed-loop frequency pre-compensation is reset to zero after the update to the location or the velocity of the UE.
4 . The UE of claim 2 ,
wherein the closed-loop frequency pre-compensation is reset to zero based at least in part on one or more of a change to the location of the UE satisfying a first threshold, a change to the velocity of the UE satisfying a second threshold, or an elapsed time since a most recent reset of the closed-loop frequency pre-compensation satisfying a third threshold.
5 . The UE of claim 4 ,
wherein one or more of the first threshold, the second threshold, or the third threshold are configured in cell-specific or UE-specific signaling.
6 . The UE of claim 1 ,
wherein the one or more processors, to determine the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation, are configured to:
determine that a physical random access channel (PRACH) was previously transmitted using a value for the open-loop frequency pre-compensation that was based on first values for the location and the velocity of the UE;
calculate the open-loop frequency pre-compensation according to the first values for the location and the velocity of the UE and current values for a satellite location and a satellite velocity; and
calculate the closed-loop frequency pre-compensation according to the one or more frequency pre-compensation commands received from the network node.
7 . The UE of claim 1 ,
wherein the one or more processors, to determine the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation, are configured to:
calculate, at a time of the update to the location or the velocity of the UE, a change to the open-loop frequency pre-compensation caused by the update to the location or the velocity of the UE; and
subtract the change to the open-loop frequency pre-compensation from the closed-loop frequency pre-compensation.
8 . The UE of claim 1 ,
wherein the one or more processors, to determine the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation, are configured to:
calculate, at a time of the update to the location or the velocity of the UE, a change to the open-loop frequency pre-compensation caused by the update to the location or the velocity of the UE;
estimate a fraction of the change to the open-loop frequency pre-compensation that has been corrected by the one or more frequency pre-compensation commands received from the network node; and
subtract the estimated fraction of the change to the open-loop frequency pre-compensation from the closed-loop frequency pre-compensation.
9 . The UE of claim 1 ,
wherein the one or more processors are further configured to:
transmit, to the network node, a notification indicating that a global navigation satellite system (GNSS) location update will be performed within a time period; and
receive, from the network node, an indication that control over one or more of the closed-loop frequency pre-compensation or a closed-loop timing advance is suspended based at least in part on the notification.
10 . The UE of claim 1 ,
wherein the one or more processors are further configured to:
transmit, to the network node, a notification indicating that a global navigation satellite system (GNSS) location update will be performed within a time period; and
receive, from the network node, one or more closed-loop timing advance or closed-loop frequency pre-compensation commands that offset a change in a total timing advance or a total frequency pre-compensation caused by the GNSS location update.
11 . A method of wireless communication performed by a user equipment (UE), comprising:
receiving one or more frequency pre-compensation commands from a network node;
determining, after an update to a location or a velocity of the UE, a closed-loop frequency pre-compensation and an open-loop frequency pre-compensation, wherein:
the closed-loop frequency pre-compensation is determined based at least in part on the one or more frequency pre-compensation commands, and
the open-loop frequency pre-compensation is determined based at least in part on the update to the location or the velocity of the UE; and
transmitting, after the update to the location or the velocity of the UE, an uplink signal using a frequency pre-compensation that is based at least in part on the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation.
12 . The method of claim 11 ,
wherein determining the closed-loop frequency pre-compensation includes resetting the closed-loop frequency pre-compensation to zero.
13 . The method of claim 12 ,
wherein the closed-loop frequency pre-compensation is reset to zero after the update to the location or the velocity of the UE.
14 . The method of claim 12 ,
wherein the closed-loop frequency pre-compensation is reset to zero based at least in part on one or more of a change to the location of the UE satisfying a first threshold, a change to the velocity of the UE satisfying a second threshold, or an elapsed time since a most recent reset of the closed-loop frequency pre-compensation satisfying a third threshold.
15 . The method of claim 14 ,
wherein one or more of the first threshold, the second threshold, or the third threshold are configured in cell-specific or UE-specific signaling.
16 . The method of claim 11 ,
wherein determining the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation includes:
determining that a physical random access channel (PRACH) was previously transmitted using a value for the open-loop frequency pre-compensation that was based on first values for the location and the velocity of the UE;
calculating the open-loop frequency pre-compensation according to the first values for the location and the velocity of the UE and current values for a satellite location and a satellite velocity; and
calculating the closed-loop frequency pre-compensation according to the one or more frequency pre-compensation commands received from the network node.
17 . The method of claim 11 ,
wherein determining the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation includes:
calculating, at a time of the update to the location or the velocity of the UE, a change to the open-loop frequency pre-compensation caused by the update to the location or the velocity of the UE; and
subtracting the change to the open-loop frequency pre-compensation from the closed-loop frequency pre-compensation.
18 . The method of claim 11 ,
wherein determining the closed-loop frequency pre-compensation and the open-loop frequency pre-compensation includes:
calculating, at a time of the update to the location or the velocity of the UE, a change to the open-loop frequency pre-compensation caused by the update to the location or the velocity of the UE;
estimating a fraction of the change to the open-loop frequency pre-compensation that has been corrected by the one or more frequency pre-compensation commands received from the network node; and
subtracting the estimated fraction of the change to the open-loop frequency pre-compensation from the closed-loop frequency pre-compensation.
19 . The method of claim 11 , further comprising:
transmitting, to the network node, a notification indicating that a global navigation satellite system (GNSS) location update will be performed within a time period; and
receiving, from the network node, an indication that control over one or more of the closed-loop frequency pre-compensation or a closed-loop timing advance is suspended based at least in part on the notification.
20 . The method of claim 11 , further comprising:
transmitting, to the network node, a notification indicating that a global navigation satellite system (GNSS) location update will be performed within a time period; and
receiving, from the network node, one or more closed-loop timing advance or closed-loop frequency pre-compensation commands that offset a change in a total timing advance or a total frequency pre-compensation caused by the GNSS location update.
21 . A network node, comprising:
one or more memories; and
one or more processors, coupled to the one or more memories, configured to:
transmit one or more frequency pre-compensation commands to a user equipment (UE); and
receive, after an update to a location or a velocity of the UE, an uplink signal using a frequency pre-compensation that is based at least in part on a closed-loop frequency pre-compensation and an open-loop frequency pre-compensation, wherein:
the closed-loop frequency pre-compensation is based at least in part on the one or more frequency pre-compensation commands, and
the open-loop frequency pre-compensation is based at least in part on the update to the location or the velocity of the UE.
22 . The network node of claim 21 ,
wherein the one or more processors are further configured to:
receive, from the UE, a notification indicating that a global navigation satellite system (GNSS) location update will be performed within a time period; and
transmit, to the UE, an indication that control over one or more of the closed-loop frequency pre-compensation or a closed-loop timing advance is suspended based at least in part on the notification.
23 . The network node of claim 21 ,
wherein the one or more processors are further configured to:
receive, from the UE, a notification indicating that a global navigation satellite system (GNSS) location update will be performed within a time period; and
transmit, to the UE, one or more closed-loop timing advance or closed-loop frequency pre-compensation commands that offset a change in a total timing advance or a total frequency pre-compensation caused by the GNSS location update.
24 . The network node of claim 21 ,
wherein the closed-loop frequency pre-compensation is reset to zero after the update to the location or the velocity of the UE.
25 . The network node of claim 21 ,
wherein the closed-loop frequency pre-compensation is reset to zero based at least in part on one or more of a change to the location of the UE satisfying a first threshold, a change to the velocity of the UE satisfying a second threshold, or an elapsed time since a most recent reset of the closed-loop frequency pre-compensation satisfying a third threshold.
26 . A method of wireless communication performed by a network node, comprising:
transmitting one or more frequency pre-compensation commands to a user equipment (UE); and
receiving, after an update to a location or a velocity of the UE, an uplink signal using a frequency pre-compensation that is based at least in part on a closed-loop frequency pre-compensation and an open-loop frequency pre-compensation, wherein:
the closed-loop frequency pre-compensation is based at least in part on the one or more frequency pre-compensation commands, and
the open-loop frequency pre-compensation is based at least in part on the update to the location or the velocity of the UE.
27 . The method of claim 26 , further comprising:
receiving, from the UE, a notification indicating that a global navigation satellite system (GNSS) location update will be performed within a time period; and
transmitting, to the UE, an indication that control over one or more of the closed-loop frequency pre-compensation or a closed-loop timing advance is suspended based at least in part on the notification.
28 . The method of claim 26 , further comprising:
receiving, from the UE, a notification indicating that a global navigation satellite system (GNSS) location update will be performed within a time period; and
transmitting to the UE, one or more closed-loop timing advance or closed-loop frequency pre-compensation commands that offset a change in a total timing advance or a total frequency pre-compensation caused by the GNSS location update.
29 . The method of claim 26 ,
wherein the closed-loop frequency pre-compensation is reset to zero after the update to the location or the velocity of the UE.
30 . The method of claim 26 ,
wherein the closed-loop frequency pre-compensation is reset to zero based at least in part on one or more of a change to the location of the UE satisfying a first threshold, a change to the velocity of the UE satisfying a second threshold, or an elapsed time since a most recent reset of the closed-loop frequency pre-compensation satisfying a third threshold.