Compressing and reporting PRS/SRS measurements for LMF-sided AI/ML positioning
Aspects presented herein may improve the efficiency and performance of artificial intelligence (AI)/machine learning (ML) (AI/ML) positioning by enabling a user equipment (UE) to compress downlink (DL) reference signal measurements to reduce reporting overhead for the DL reference signal measurements. In one aspect, a UE performs at least one channel impulse response (CIR) measurement or at least one channel frequency response (CFR) measurement for a set of positioning reference signals (PRSs). The UE compresses the at least one CIR measurement or the at least one CFR measurement for the set of PRSs. The UE reports, for a network entity, one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs.
1 . An apparatus for wireless communication at a user equipment (UE), comprising:
at least one memory; and
at least one processor coupled to the at least one memory and, based at least in part on information stored in the at least one memory, the at least one processor, individually or in any combination, is configured to:
perform at least one channel impulse response (CIR) measurement or at least one channel frequency response (CFR) measurement for a set of positioning reference signals (PRSs);
compress the at least one CIR measurement or the at least one CFR measurement for the set of PRSs;
report, for a network entity, one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs;
receive, from the network entity, a request to indicate whether the UE is capable of reporting the at least one compressed CIR measurement or the at least one compressed CFR measurement; and
transmit, to the network entity based on the request, a capability indication of the UE to report the at least one compressed CIR measurement or the at least one compressed CFR measurement and at least one compression method supported by the UE.
2 . The apparatus of claim 1 , wherein the at least one compressed CIR measurement or the at least one compressed CFR measurement includes at least one of: an absolute value of the at least one compressed CIR measurement, an absolute value of the at least one compressed CFR measurement, a complex value of the at least one compressed CIR measurement, a complex value of the at least one compressed CFR measurement, a timing indicator of the at least one compressed CIR measurement, or a frequency indication of the at least one compressed CFR measurement.
3 . The apparatus of claim 1 , wherein the at least one processor, individually or in any combination, is further configured to:
receive, from the network entity, a configuration for compressing the at least one CIR measurement or the at least one CFR measurement.
4 . The apparatus of claim 1 , wherein the at least one processor, individually or in any combination, is further configured to:
receive the set of PRSs from at least one network node.
5 . The apparatus of claim 1 , wherein to compress the at least one CIR measurement or the at least one CFR measurement for the set of PRSs, the at least one processor, individually or in any combination, is configured to:
select a fraction of PRSs from the set of PRSs for the at least one CIR measurement or the at least one CFR measurement, or for reporting one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement.
6 . The apparatus of claim 5 , wherein to select the fraction of PRSs from the set of PRSs, the at least one processor, individually or in any combination, is configured to:
select every k th subcarrier of occupied subcarriers in the set of PRSs, where k is an integer.
7 . The apparatus of claim 6 , wherein the at least one processor, individually or in any combination, is further configured to:
select every first unoccupied subcarrier that is adjacent to the selected every k th subcarrier.
8 . The apparatus of claim 1 , wherein to compress the at least one CIR measurement or the at least one CFR measurement for the set of PRSs, the at least one processor, individually or in any combination, is configured to:
select a portion of samples from the at least one CIR measurement or the at least one CFR measurement for reporting one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement.
9 . The apparatus of claim 8 , wherein to select the portion of samples from the at least one CIR measurement or the at least one CFR measurement, the at least one processor, individually or in any combination, is configured to:
select first N contiguous samples with magnitudes exceeding a magnitude threshold, where N is an integer;
select a set of samples whose magnitude is associated with a maximum CIR measurement or a maximum CFR measurement; or
select first M peaks in the CIR measurement or the CFR measurement.
10 . The apparatus of claim 1 , wherein to compress the at least one CIR measurement or the at least one CFR measurement for the set of PRSs, the at least one processor, individually or in any combination, is configured to:
select a subset of PRSs from the set of PRSs for reporting one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement based on at least one of:
the subset of PRSs having a signal-to-noise ratio (SNR) above an SNR threshold,
the subset of PRSs having a delay spread above or below a delay spread threshold, or
the subset of PRSs having a Rician factor above or below a Rician factor threshold.
11 . The apparatus of claim 10 , wherein the subset of PRSs corresponds to top L PRSs with highest measurements in the at least one CIR measurements or the at least one CFR measurement.
12 . The apparatus of claim 1 , wherein to compress the at least one CIR measurement or the at least one CFR measurement for the set of PRSs, the at least one processor, individually or in any combination, is configured to:
provide the at least one CIR measurement or the at least one CFR measurement for the set of PRSs for an artificial intelligence (AI)/machine learning (ML) (AI/ML) model; and
receive, from the AI/ML model, the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs.
13 . The apparatus of claim 1 , further comprising a transceiver coupled to the at least one processor, wherein to report the one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs, the at least one processor, individually or in any combination, is configured to:
report, via the transceiver, the one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs.
14 . A method of wireless communication at a user equipment (UE), comprising:
performing at least one channel impulse response (CIR) measurement or at least one channel frequency response (CFR) measurement for a set of positioning reference signals (PRSs);
compressing the at least one CIR measurement or the at least one CFR measurement for the set of PRSs;
reporting, for a network entity, one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs;
receiving, from the network entity, a request to indicate whether the UE is capable of reporting the at least one compressed CIR measurement or the at least one compressed CFR measurement; and
transmitting, to the network entity based on the request, a capability indication of the UE to report the at least one compressed CIR measurement or the at least one compressed CFR measurement and at least one compression method supported by the UE.
15 . An apparatus for wireless communication at a network entity, comprising:
at least one memory; and
at least one processor coupled to the at least one memory and, based at least in part on information stored in the at least one memory, the at least one processor, individually or in any combination, is configured to:
transmit, for a user equipment (UE), an indication to report one or more of at least one compressed channel impulse response (CIR) measurement or at least one compressed channel frequency response (CFR) measurement for a set of positioning reference signals (PRSs);
receive, from the UE, one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs;
transmit, to the UE, a request to indicate whether the UE is capable of reporting the at least one compressed CIR measurement or the at least one compressed CFR measurement; and
receive, from the UE based on the request, a capability indication of the UE to report the at least one compressed CIR measurement or the at least one compressed CFR measurement and at least one compression method supported by the UE.
16 . The apparatus of claim 15 , wherein the at least one compressed CIR measurement or the at least one compressed CFR measurement includes at least one of: an absolute value of the at least one compressed CIR measurement, an absolute value of the at least one compressed CFR measurement, a complex value of the at least one compressed CIR measurement, a complex value of the at least one compressed CFR measurement, a timing indicator of the at least one compressed CIR measurement, or a frequency indication of the at least one compressed CFR measurement.
17 . The apparatus of claim 15 , wherein the at least one processor, individually or in any combination, is further configured to:
configure at least one network node to transmit the set of PRSs to the UE.
18 . The apparatus of claim 15 , wherein the at least one processor, individually or in any combination, is further configured to:
transmit, for the UE, a configuration for compressing the at least one CIR measurement or the at least one CFR measurement.
19 . The apparatus of claim 18 , wherein the configuration configures the UE to select a fraction of PRSs from the set of PRSs for the at least one CIR measurement or the at least one CFR measurement, or for reporting one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement.
20 . The apparatus of claim 19 , wherein the configuration further configures the UE to select every k th subcarrier of occupied subcarriers in the set of PRSs, where k is an integer.
21 . The apparatus of claim 20 , wherein the configuration further configures the UE to select every first unoccupied subcarrier that is adjacent to the selected every k th subcarrier.
22 . The apparatus of claim 18 , wherein the configuration configures the UE to select a portion of samples from the at least one CIR measurement or the at least one CFR measurement for reporting one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement.
23 . The apparatus of claim 22 , wherein the configuration further configures the UE to select first N contiguous samples with magnitudes exceeding a magnitude threshold, where N is an integer,
select a set of samples whose magnitude is associated with a maximum CIR measurement or a maximum CFR measurement, or
select first M peaks in the CIR measurement or the CFR measurement.
24 . The apparatus of claim 18 , wherein the configuration configures the UE to select a subset of PRSs from the set of PRSs for reporting one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement based on at least one of:
the subset of PRSs having a signal-to-noise ratio (SNR) above an SNR threshold,
the subset of PRSs having a delay spread above or below a delay spread threshold, or
the subset of PRSs having a Rician factor above or below a Rician factor threshold.
25 . The apparatus of claim 24 , wherein the subset of PRSs corresponds to top L PRSs with highest measurements in the at least one CIR measurements or the at least one CFR measurement.
26 . The apparatus of claim 18 , wherein the configuration configures the UE to provide the at least one CIR measurement or the at least one CFR measurement for the set of PRSs for an artificial intelligence (AI)/machine learning (ML) (AI/ML) model and receive, from the AI/ML model, the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs.
27 . The apparatus of claim 15 , further comprising a transceiver coupled to the at least one processor, wherein to transmit the indication, the at least one processor, individually or in any combination, is configured to transmit the indication via the transceiver, and wherein to receive one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs, the at least one processor, individually or in any combination, is configured to receive, via the transceiver, one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs.
28 . A method of wireless communication at a network entity, comprising:
transmitting, for a user equipment (UE), an indication to report one or more of at least one compressed channel impulse response (CIR) measurement or at least one compressed channel frequency response (CFR) measurement for a set of positioning reference signals (PRSs);
receiving, from the UE, one or more of the at least one compressed CIR measurement or the at least one compressed CFR measurement for the set of PRSs;
transmitting, to the UE, a request to indicate whether the UE is capable of reporting the at least one compressed CIR measurement or the at least one compressed CFR measurement; and
receiving, from the UE based on the request, a capability indication of the UE to report the at least one compressed CIR measurement or the at least one compressed CFR measurement and at least one compression method supported by the UE.