论文部分内容阅读
ＧＰＳ系统是现阶段功能最全、精度最高的卫星导航系统，大气层对ＧＰＳ系统定位和定时的影响已成为一个不可忽略的重要因素．本文从广州地区两天各两个时刻的气象探空资料中分析了各个时刻高空中几个已知高度点的折射指数，然后用线性处理的办法得到了１７ｋｍ范围左右高空中折射指数的模型，大气指数模型与此模型相比较，几个点折射指数的均方差很小，最后用这两种模型分别计算两天各两个时刻大气层对ＧＰＳ信号在垂直传播时所引起的附加时间延迟，二者之差最大不大于０．３ｎｓ，用指数模型可基本反映广州地区大气层对ＧＰＳ信号传播时间延迟的影响。
The GPS system is the most complete and accurate satellite navigation system at this stage. The influence of the atmosphere on the positioning and timing of the GPS system has become an important factor that can not be ignored. Based on the meteorological sounding data of two days and two days in Guangzhou, this paper analyzes the refraction index of several known altitude points at various times at high altitude, then obtains the model of high altitude refraction index about 17km by linear processing method, Compared with this model, the mean square error of several points of refraction index is very small. Finally, the two models are used to calculate the additional time delay caused by the atmosphere in the vertical propagation of GPS signal at two different time intervals. The maximum difference is not greater than 0.3ns, using the exponential model can basically reflect the atmosphere of Guangzhou on GPS signal propagation time delay.