Beamforming (BF) often requires the base station (BS) to master precise angle information from the uplink channel impulse response (CIR). Based on the three-dimensional (3D) wireless multipath channel in the fifth generation (5G) new radio (NR) system, we can easily obtain the channel frequency response (CFR) of the orthogonal frequency division multiplexing (OFDM) structure using the sounding reference signal (SRS). However, when CFR is converted into CIR by the inverse fast Fourier transform (IFFT), the phenomenon of leakage will occur. In this paper, we combine the time-delay and spatial domains to design an algorithm for analyzing ultra-high-resolution paths in the presence of coherent sources and energy leakage. And we theoretically expound the advantages of using leaked CIR instead of CFR to extract angle information. The experimental results show that the proposed algorithm can perfectly construct the power angle spectrum (PAS) and reconstruct the CIR in beam domain based on the data received by the uplink at the BS. The original CIR in beam domain received by the BS further verifies the correctness of our results.
Paper
Full text
Angular Information Extraction Algorithm of 5G-NR Uplink Wireless Channel Based on SRS
Semantic Scholar · Engineering · 2022
Abstract
Beamforming (BF) often requires the base station (BS) to master precise angle information from the uplink channel impulse response (CIR). Based on the three-dimensional (3D) wireless multipath channel in the fifth generation (5G) new radio (NR) system, we can easily obtain the channel frequency response (CFR) of the orthogonal frequency division multiplexing (OFDM) structure using the sounding reference signal (SRS). However, when CFR is converted into CIR by the inverse fast Fourier transform (IFFT), the phenomenon of leakage will occur. In this paper, we combine the time-delay and spatial domains to design an algorithm for analyzing ultra-high-resolution paths in the presence of coherent sources and energy leakage. And we theoretically expound the advantages of using leaked CIR instead of CFR to extract angle information. The experimental results show that the proposed algorithm can perfectly construct the power angle spectrum (PAS) and reconstruct the CIR in beam domain based on the data received by the uplink at the BS. The original CIR in beam domain received by the BS further verifies the correctness of our results.