UWB LFM echo signal detection and time-delay estimation based on compressive sensing

Abstract

UWB linear frequency modulated (LFM) signals are widely used in radar, sonar and communication systems. In some applications, the detection of LFM signals and estimation of time-delay are very important. It needs very high sampling rate to address the problems for UWB LFM signal under Nyquist sampling theory which exceeds the current ADC capacity. In this paper, we propose a Compressive Sensing (CS) based method to solve the problem with ultra low sampling rate. We adopt an FrFt based sparse dictionary for CS because of the energy concentration property of LFM signal in the fractional Fourier domain. The performance is much better than the already existed method which used signal-matched sparse dictionary in noise condition. Experiments based on simulated data are carried out to testify the results.