Compressed Sensing Theory In The Application Of The Uwb System

Ultra-wideband (UWB) has wide applications in high speed wireless communications, ranging and imaging, wireless sensor networks, and radar detection because of its characteristics of good anti-interference, high transmission rate, large information capacity and low power consumption etc. However, the traditional sampling technology based on the Nyquist-Shannon law can not meet the demand of high-speed sampling in UWB system. The high rate sampling technology becomes a big technical bottleneck in the UWB systems.Compressive sensing (CS) is a novel sampling and processing theory that can utilize quite lower rate for accurately sampling and reconstruction of the compressible signals without the limitation of Nyquist-Shannon sampling theorem. CS theory breaks the traditional signal sampling and processing mode and provides a novel technical solution to the sampling of UWB signals.We carry out research work on the application of CS theory in UWB sampling system. First, in order to put the CS theory used in UWB sampling system well, we analysis and introduce the main content and algorithm of the CS theory. Secondly, we propose a UWB signal processing method based on the CS theory. As examples, numerical simulations are given to processing the Gaussian-modulated time-domain transient UWB array signals received by a linear dipole array and a circular dipole array. The numerical results demonstrate that the proposed CS method is feasible and effective. Finally, in order to further reduce the sampling rate, we optimize the proposed CS-based UWB signal processing method. At the same time, we provide some effective method to select a set of suitable sparse basis functions. Numerical results show that, Gaussian-modulated time-domain transient UWB array signals can be sampled and exactly reconstructed at about5%of the Nyquist-Shannon sampling rate using the improved UWB signal processing method, which has great significance to overcome the technical bottleneck of the high rate sampling in the UWB system. The UWB signal processing method based on the CS theory and the method to select sparse basis functions provided by us can provide researchers some useful guidance to low rate sample or sparse process other kinds of signals.