In order to play a part in evaluation and manage of water resource for weather radar, the quantitative rainfall measurement of dual polarization doppler weather radar is developed. And based on the observed values of ombrometer, the differences of the measured values derived from different methods are analysed. The results show: The rainfall using KDP to calculate, i.e. R(KDP) method, is proximal to the data of ombrometer; R(ZH) and R(ZH, ZDR) method is underestimate rainfall obviously; R(ZDR, KDP) method is overestimate rainfall. With further analysis, rainfall measured by dual-polarization radar, especially from R(KDP) method, has higher precision, and provide the spatial distribution of the rainfall and the position of strong center well.

The active phased array antenna is a direction of modern radar development. But it is expensive. So the key in meteorological radar design is to get high ratio of capability and cost. We used 400 cross-polarization half wave diploes as radiation unit to get a high efficiency and reliability antenna, it also has low side lobe by Taylor weighting. 20 transmit/receive(T/R) modules produced too little heat to disperse, so it can be cooled by nature wind. 40 power dividers which one is divided into twenty parts and 1 power combiner decreased transmission loss. This antenna is fit for the need of wind profiling radar.