VHF雷达回波距离拓展特性频率依赖关系研究

针对相干散射雷达探测中受方向敏感性的影响产生距离拓展的现象，研究了在不规则体尺度参数影响下回波距离拓展特性与雷达频率之间的依赖关系. 基于相干散射雷达回波方程，对回波展宽随不规则体尺度变化进行了计算，开展了雷达工作频率与距离拓展特性依赖关系的仿真，得到了雷达工作频率-展宽宽度拟合斜率随不规则体尺度变化规律. 结果表明，回波展宽宽度与雷达频率之间为线性相关，拟合斜率与不规则体纵向尺度之间存在一一对应的关系，通过线性回归计算的斜率可以用于反推不规则体的纵向尺度参数. 由于斜率计算无需获取绝对的雷达天线增益、馈线损耗和发射功率等参数，因此可为未标定的 VHF雷达提供一种新的不规则体尺度探测方法，这对开发新的不规则体探测技术具有重要意义.

Research on frequency dependence of range extension in VHF radar echo

According to facts that the range extension of the echo due to the influence of the aspect sensitivity in the detection of coherent scattering radar, this paper studies the dependence of the echo range extension and radar frequency are affected by the scales of the irregularities. Based on the coherent scattering radar echo equation, the echo broadening with the scales of the irregularities is calculated, and the simulation of the dependence of the radar operating frequency and the range extension is carried out, the variation of the fitting slope of the radar operating frequency and the broadening width with the scales of the irregularities is obtained. The results show that there is a linear correlation between the echo broadening width and the radar frequency, and there is the only correspondence between the fitting slope and the longitudinal scale of the irregularities. The slope calculated by linear regression can be used to reverse the scale of the irregularities. Since the calculation of slope does not require the acquisition of absolute radar antenna gain, feeder loss and transmission power, it can provide a new scale detection method of the irregularities for non-calibration VHF radar. The result is of significance for the development of new detection techniques for the irregularities.