Ultra-wideband Distance System Signal Processing Methods

Ultra Wide-Band fixed distance system transmits extremely narrow pulse strings modulated by pseudo-code position, receives the target reflection signal of distance range which is realized through the range gate delay, and by demodulating, sampling accumulation, and processing the low-frequency signal, finally outputs identification information. With its high fixed distance precision and strong anti-interference ability, the Ultra Wide-Band fixed distance system has attracted more and more attention recently. The theory and critical techniques relating to UWB fixed distance system have developed rapidly. However, because the target has multiple scattering centers in the UWB signal’s shinning, echo signal has a complex waveform, which is a superposition of multiple reflection signal. The signal processing methods for narrowband signal is not suitable, so this paper researches on the signal processing method of UWB fixed distance system.Based on the study of UWB fixed distance system’s principle, firstly, the echo signal of the UWB fixed distance system is modeled and simulated. Also, the paper gives the effects that some high frequency continuous wave interferences make on UWB system. Then, an acquisition system is designed. Through the acquisition experiment, the echo of UWB fixed distance system in actual working environment is obtained. And through the analysis of the echo’s characteristics, the paper comes to the conclusion that the main interference contained in echo signal is narrow band interference. After that, according to the interference’s type, the existing signal processing algorithms have been improved. Advanced signal processing methods, for example, the wavelet transform and short time Fourier transform are applied to suppress interference and recognize signal for UWB fixed distance system. And the suggested signal processing method is carried out in the Matlab software environment, through the analysis of improvement on signal-to-noise ratio and anti-jamming performance, a good simulation results is given. Finally, the hardware simulation platform of UWB signal processing algorithm is established, the fast implementation algorithm of the key algorithm is introduced, which is realized through DSP programming, and achieves good results. The simulation results verify the feasibility, reliability and real-time performance of the new algorithm.