Spectral and spatial stitching for radio frequency sensing

1 . A device comprising:

a transmitter coupled to at least one antenna;

a receiver coupled to the at least one antenna; and

a processing device coupled to the transmitter and the receiver, the processing device for performing operations comprising:

responsive to receiving a plurality of channel frequency response (CFR) measurements from an antenna operating at a low-bandwidth range, generating, based on the plurality of CFR measurements, a channel state information (CSI) across a high-bandwidth range; and

determining, based on the CSI, a Doppler shift across the high-bandwidth range.

2 . The device of claim 1 , wherein each CFR measurement of the plurality of CFR measurements is measured from different channels of the antenna at varying times.

3 . The device of claim 1 , wherein the high-bandwidth range is greater than the low-bandwidth range.

4 . The device of claim 1 , wherein generating the CSI across the high-bandwidth range comprises:

identifying a subset of the plurality of CFR measurements;

obtaining, from each CFR measurement of the subset, one or more subcarrier CFR measurements from a plurality of subcarrier CFR measurements of a respective CFR measurement; and

converting the one or more subcarrier CFR measurements associated with each CFR measurement of the subset to the CSI across the high-bandwidth range.

5 . The device of claim 4 , wherein obtaining, from each CFR measurement of the subset, the one or more subcarrier CFR measurements from the plurality of subcarrier CFR measurements of the respective CFR measurement comprises:

for each CFR measurement of the subset, determining an age of the respective CFR measurement;

identifying, based on the age, a number of subcarrier CFR measurements to select from the plurality of subcarrier CFR measurements of the respective CFR measurement; and

selecting, based on the identified number, the one or more subcarrier CFR measurements.

6 . The device of claim 5 , wherein identifying, based on the age, the number of subcarrier CFR measurements to select from the plurality of subcarrier CFR measurements of the respective CFR measurement comprises:

determining the number of subcarrier CFR measurements associated with the plurality of subcarrier CFR measurements of the respective CFR measurement; and

applying, based on the age, a weight value to the number of subcarrier CFR measurements to determine the number of subcarrier CFR measurements to select from the plurality of subcarrier CFR measurements of the respective CFR measurement.

7 . The device of claim 1 , wherein generating the CSI across the high-bandwidth range comprises:

providing each CFR measurement of the plurality of CFR measurements to a predictive filter;

obtaining, from the predictive filter, a plurality of predicted CSIs across the high-bandwidth range; and

combining the plurality of predicted CSIs across the high-bandwidth range into the CSI across the high-bandwidth range.

8 . The device of claim 1 , wherein generating the CSI across the high-bandwidth range comprises:

providing the plurality of CFR measurements to a machine learning model; and

obtaining, from the machine learning model, the CSI across the high-bandwidth range.