Compressive Wideband Spectrum Sensing and Carrier Frequency Estimation with Unknown Mimo Channels
We consider the problem of joint wideband spectrum sensing and carrier frequency estimation in a sub Nyquist sampling framework. Specifically, a multi antenna receiver is used to estimate the carrier frequencies and power spectra of multiple narrowband transmissions that spread over a wide frequency band. Unlike existing works that assume the source signals impinge on the receiver via a line of sight (LOS) path, we consider a more practical multiple input multiple output (MIMO) channel characterized by multipath propagation. A new sub Nyquist sampling architecture is proposed, where each antenna output passes through two channels, namely, a direct path and a delayed path with a predetermined time delay. The signal at each channel is then sampled by a synchronized low rate analog to digital converter (ADC) We utilize the collected data samples to build a set of cross correlation matrices with different time lags and develop a CANDECOMP/PARAFAC (CP) decomposition based method to recover the carrier frequencies and power spectra of the source signals. Simulation results are presented to illustrate the effectiveness of the proposed method.
ICASSP 2021 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)