A Method for Radar Beam Occultation Analysis Using SNR of Receiver

The situation of terrain blockage is known as a vital part for selecting radar site, which is rather important to the quality of radar data. In the past few years, it is popular to use DEM (Digital Elevation Model) data to analyze the radar beam occultation area. However, this method can only reveal a gross feature of terrain blockage distribution and is dependent on the precision of DEM data. Besides, the application of DEM calculation requires some preconditions, which are not always satisfied in most occasions. All these limitations aforementioned will cause uncertainties. In order to solve this problem, the authors proposed a new method, namely SNR method, via analyzing the “noise” amplitude of the radar receiver. According to the classic blackbody radiation theory, the entire object in the world will emits radiation based on its temperature. The radiation could be reflected as a fluctuation of base signal (or “noise signal”) and can be interpreted to recognize the terrain blockage. By checking the “noise” signal in IQ data, a terrain blockage distribution can be identified. Based on real time radar data, the SNR method is effective in recognizing immobile targets around radar. Meanwhile, without including extra hardware or financial budget, the SNR method is simple and feasible.