Techniques for srs estimation in wireless systems

An apparatus for use in a base station, the apparatus comprising:

• processing circuitry, wherein to configure the base station for sounding reference signal (SRS) estimation in a Fifth Generation New Radio (5G NR) and beyond wireless network, the processing circuitry is to:
• perform SRS sequence de-mapping of orthogonal frequency division multiplexing (OFDM) symbols to generate a de-mapped sequence, the OFDM symbols corresponding to an uplink (UL) stream with SRS transmissions from a plurality of user equipments (UEs);
• perform a first least square (LS) estimation based on the de-mapped sequence to obtain a first LS sequence;
• apply a time domain (TD) transformation and a frequency domain (FD) transformation to the first LS sequence to generate a first partial SRS channel estimate sequence;
• perform a second LS estimation based on the de-mapped sequence to obtain a second LS sequence;
• filter the second LS sequence to generate a second partial SRS channel estimate sequence;
• and
• generate a full SRS channel estimate sequence corresponding to the SRS transmissions, based on the first partial SRS channel estimate sequence and the second partial SRS channel estimate sequence;
• and
• memory coupled to the processing circuitry and configured to store the OFDM symbols.

A computer-readable storage medium that stores instructions for execution by one or more processors of a base station, the instructions to configure the base station for sounding reference signal (SRS) estimation in a Fifth Generation New Radio (5G NR) and beyond wireless network, and to cause the base station to perform operations comprising:

• performing SRS sequence de-mapping of orthogonal frequency division multiplexing (OFDM) symbols to generate a de-mapped sequence, the OFDM symbols corresponding to an uplink (UL) stream with SRS transmissions from a plurality of user equipments (UEs);
• performing a first least square (LS) estimation based on the de-mapped sequence to obtain a first LS sequence;
• applying a time domain (TD) transformation and a frequency domain (FD) transformation to the first LS sequence to generate a first partial SRS channel estimate sequence;
• performing a second LS estimation based on the de-mapped sequence to obtain a second LS sequence;
• filtering the second LS sequence to generate a second partial SRS channel estimate sequence;
• and
• generating a full SRS channel estimate sequence corresponding to the SRS transmissions, based on the first partial SRS channel estimate sequence and the second partial SRS channel estimate sequence.

A method for sounding reference signal (SRS) estimation in a Fifth Generation New Radio (5G NR) and beyond wireless network, the method comprising:

• performing SRS sequence de-mapping of orthogonal frequency division multiplexing (OFDM) symbols to generate a de-mapped sequence, the OFDM symbols corresponding to an uplink (UL) stream with SRS transmissions from a plurality of user equipments (UEs);
• performing a discrete Fourier transformation (DFT)-based signal processing sequence using the OFDM symbols to obtain a first partial SRS channel estimate sequence corresponding to the SRS transmissions;
• performing a minimum mean square error (MMSE)-based signal processing sequence using the OFDM symbols to obtain a second partial SRS channel estimate sequence corresponding to the SRS transmissions;
• concatenating the first partial SRS channel estimate sequence and the second partial SRS channel estimate sequence to generate a full SRS channel estimate sequence corresponding to the SRS transmissions;
• and
• estimating a UL channel associated with the plurality of UEs based on the full SRS channel estimate sequence.