色散特性对毫米波频率步进雷达影响的研究

对影响毫米波频率步进雷达分辨率的主要因素进行了分析。除目标速度以外,为毫米波频率步进雷达提供频率信号的频率源的色散特性也会对雷达分辨率造成恶化影响。微波频段上的色散特性会被搬移到毫米波频段,导致毫米波发射信号和本振信号的初始相位差不为常数,对雷达系统尤其是距离分辨率造成严重影响。仿真结果与实验结果一致。为了抵消色散特性对雷达分辨率的恶化影响,可以通过对色散特性的补偿来实现。色散特性补偿的方法被应用到实现W波段频率步进频率源的设计中,满足了0.45 m距离分辨率的要求。

Effect of Dispersion to Millimeter Wave Stepped Frequency Waveforms Radar

As one of high-resolution radars, millimeter wave stepped frequency waveforms radar is successfully and widely used in many military applications. Main factors affecting the performance of radar are analyzed. Apart from target velocity, the dispersion of frequency synthesizer providing signals to radar also deteriorates the performance of radar. Specifically speaking, the dispersion in microwave band will be transferred to millimeter-wave band, this will result in the fact that the initial phase difference between transmitter and local oscillator is not constant, and brings bad impact on the resolution of radar. In order to ameliorate such effect, one possible way is to compensate dispersion. In this paper, an effective way to compensate dispersion is successfully applied in the design of a W-band stepped frequency waveforms radar. The final experiment shows that it can meet the requirement of 0.45 m range resolution.