改进射线描迹的低仰角散射斜延迟实时估计  

Real-time Estimation of Tropospheric Scattering Slant Delay of Low-elevation Obtained by Improved Ray Tracing

作　　者：吴文溢 钟方平[1] 王万鹏[1] 陈西宏[2] 朱丹[1] WU Wenyi;ZHONG Fangping;WANG Wanpeng;CHEN Xihong;ZHU Dan(Northwest Institute of Nuclear Technology,Xi’an 710024,China;Air and Missile Defense College,Air Force Engineering University,Xi’an 710051,China)

机构地区：[1]西北核技术研究所,西安710024 [2]空军工程大学防空反导学院,西安710051

出　　处：《电子与信息学报》2019年第10期2366-2372,共7页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(611701525)~~

摘　　要：针对任意测站的对流层散射斜延迟估算时存在探空气象数据不易实时获取的不足,该文提出一种利用地面气象参数内插改进射线描迹计算公式的对流层散射斜延迟估计算法。该算法利用中纬度大气气象参数公式推导了折射指数随地心距变化的关系式,并采用气象参数内插方法获取温度变化率和水汽压变化率,克服了射线描迹法对探空数据的依赖。根据亚洲地区6个国际GPS服务(IGS)测站2012年的实测气象数据,验证了该文算法解算天顶延迟年平均偏差的绝对值在1 cm以内;选取基线距离适宜的3个测站分成3组散射通信比对站,利用射线描迹法计算了其在0°~5°入射角下全年的斜延迟,结果表明,3组比对站进行单向传输的最大斜延迟为17.03~33.10 m;进行双向时间比对相互抵消95%时,时间延迟为2.88~5.52 ns。Considering the disadvantage of oblique delay estimation of tropospheric scattering at arbitrary stations,which is difficult to obtain real-time sounding meteorological data,an oblique delay estimation algorithm of tropospheric scattering based on improved ray tracing method with ground meteorological parameters is proposed.In order to get rid of the method’s dependence on radiosonde data,the algorithm infers the relationship between refractive index and altitude through the formula of meteorological parameters in the model of medium latitude atmosphere.The interpolation of meteorological parameters in the model of UNB3m is used to gain the coefficient of temperature and water vapor pressure.Meteorological data for 2012 from 6 International GNSS Service(IGS)stations in Asia are selected to test the applicability of new method,the results suggest that precision is less than 1 cm.Then,the tropospheric slant delays of three parts observation stations under different angles of incidence(0°~5°)are calculated by the modified algorithm.The results suggest that the maximum delay is 17.03~33.10 m in a single way time transfer.In two way time transfer,when the delay can counteract 95%,time delay is 2.88~5.52 ns.

关 键 词：对流层散射 斜延迟 射线描迹法 折射指数 

分 类 号：TN011[电子电信—物理电子学]