The Impact Of Rotary Joint On Deviations Of Amplitude And Phase And Its Calibration For Dual-Polarization Weather Radar

The variation of rotary joint is one of the primary reasons that result in dynamic deviation of Z(DR) and Phi(DP) as polarimetric parameters, and external instruments are needed to detect and calibrate to ensure the amplitude and phase consistency for dual-polarization weather radar. This paper analyzes the impact of rotary joint of dual-polarization weather radar on Z(DR) and Phi(DP), and it proposes a detection and calibration method using external instrument based on baseline curve of deviation. Then this method is used to test and calibrate a S-band dual-polarization weather radar produced by Beijing Metstar Radar Co., Ltd., and the results are analyzed. It is shown that Z(DR) and Phi(DP) deviation introduced by rotary joint can satisfy requirement of relevant technical specifications, and this method can reduce deviation of amplitude and phase through calibration to enhance the reliability of radar observation data effectively.