关键词: 合成超宽带, 多普勒色散, 距离多普勒耦合, 补偿量化误差, 快速傅里叶变换

Abstract: The synthetical ultra-wideband (UWB) range profile and velocity information of a target can be obtained directly via the signal processing of a signal, i.e., via the waveform of stepped frequency during pulse trains. However, mismatch error of fast Fourier transform (FFT) output introduced by Doppler dispersion and range-Doppler coupling often results in serious distortion of the range profile. This article introduces a method of eliminating the effect of Doppler dispersion on range profile, analyzes the influence of the coupling between range and Doppler on range profile and compensates the influence. The article then proceeds from discussing the impact on range profile to the existence of quantified compensation errors caused by the error in calculating velocity, and derives an equation to estimate the shift of range profile brought by the errors of quantified compensation. A technique by the name of iterative and dimidiate approach is proposed to improve the N resolution of the calculated target velocity (where N denotes the number of pulse trains). Therefore, the proposed approach can finally yield true target high resolution range profile. The simulation results show that Doppler dispersion is eliminated and the restriction of N is relieved.

Key words: synthetical ultra-wideband, Doppler dispersion, range-Doppler coupling, error of quantified compensation, fast Fourier transform