An Arithmetic to Enhance the Detecting Ability of Dual-polarization Weather Radar for Weak Echoes

Because the dual-polarization weather radar transmitted power in each polarimetric channel two times or 3 dB lower than in the "legacy" single polarization channel, which can cause the decrease of sensitivity. It means that the weakest signals just above the noise level are lost in the polarimetric system. Some important weather features in weak signal may become harder to identify with the polarimetric radar. In order to mitigate this systematic problem, this paper estimate the echo power based on coherent summation of two channel signals to enhance the detecting ability for dual-polarization weather radar. And also do some experiment by using IQ data of dual-polarization weather radar and analysis according to the coherent summation arithmetic. The result shows that using coherent summation arithmetic can enhance the detecting sensitivity by 3.77dB for dual-polarization weather radar and increase the detecting ability for weak echoes. In this way, the radar echoes can be more accurate and abundant.