以中国气象科学研究院灾害天气国家重点实验室C波段双线偏振雷达2011年完成升级改造后观测的一次降水过程资料为例,讨论其探测资料质量及其对降水粒子的探测性能,统计分析降水回波的差分反射率因子ZDR、零滞后互相关系数ρHV（0）与信噪比SNR的关系,以及系统初始相位的稳定性,反射率因子ZH分别与差分反射率因子ZDR和差传播相移率KDP资料的一致性。结果表明：差分反射率因子ZDR及零滞后互相关系数ρHV（0）在信噪比小于15 dB时受噪声影响较大,资料变得不可信;距离雷达3 km以内的偏振参量不稳定,资料不可用。系统初始相位在观测过程中相对稳定,无明显波动。利用垂直扫描数据进行系统误差订正后的ZDR资料能较好地反映降水粒子的实际情况,而对差传播相移ΦDP分类处理后拟合的差传播相移率KDP资料也与实际情况相一致。%Based on the large area of stratiform precipitation observation in 2011 by an upgraded C-band dual linear polarimetric radar which was installed in the State Key Laboratory of Severe Weather（LaSW）,Chinese Academy of Meteorological Sciences（CAMS）,the radar’s measurement quality and detection ability are presented.Differential reflectivity ZDR,cross-correlation coefficient ρHV（0） and their relationships with signal-to-noise ratio SNR respectively,the stability of radar system initial differential phase and the consistency of rainfall data are all analyzed.The results indicate that if theis less than 15dB,ZDR is greatly impacted by the noise,and ρHV（0） becomes incredible.Polarimetric variables of radial bins within a range of 3km from radar are too instable to use.The radar system is stable relatively during the observation procedure and the system initial differential phase doesn’t fluctuate obviously.The system error revised ZDR by the vertical incidence method and the specific differential phase KDP calculated from differential propagation phase shift ΦDP which is processed by the classification processing method coincide with the actual situation.
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