为了说明载荷和平台参数设置对星载毫米波雷达探测性能的影响,文中构建了由9 个子模块构成的星载毫米波雷达正演模拟器,利用天气研究与预报模型模拟云场景以及随机数据正演仿真对载荷和平台参数进行了敏感性分析。分析发现:星载毫米波雷达载荷平台采用天线直径为2. 5 m、轨道高度为400 km~450 km 的配置时,其探测性能相较于云廓线雷达提升超过7 倍;其信噪比达到25 dB 时,可以很好地减小噪声对反射率因子提取的影响;雷达标定常数误差在3. 36%以内时,可以满足反射率因子±1 dB 的探测精度要求;对于轨道高度为400 km 的星载毫米波雷达平台,当姿态角变化大于0. 13°时,其前后两次星下点观测区域完全错位,而当姿态角变化大于0. 75°时,其前后两次星下点位置相差5 km。

A forward simulation model for spaceborne millimeter wave radar consisting of 9 sub modules is constructed in this paper. Weather research and forecasting simulation of cloud scenarios and random data simulated by this forward model are used for the sensitivity analysis of payload and platform parameters which is carried out to illustrate the influence of payload and platform parameter settings on the detection performance of the spaceborne millimeter wave radar. Analysis shows that the detection performance of the spaceborne millimeter wave radar with the configuration of antenna diameter of 2. 5 m and orbital altitude of 400 km~ 450 km is more than 7 times higher than CloudSat cloud profile radar; the impact of noise on the extraction of reflectivity factor can be effectively reduced when the signal-to-noise ratio reaches 25 dB; the detection accuracy of reflectivity factor within ±1 dB can be met when the radar calibration constant error is within 3. 36%; for a spaceborne millimeter wave radar platform with an orbital altitude of 400 km, the two sub-satellite observation areas before and after are completely misaligned when the attitude angle changes by more than 0. 13 °, meanwhile the positions of the two sub-satellite points before and after differ by 5 km when the attitude angle changes by more than 0. 75 °.

P412.25