【作者】 刘晓刚；

【导师】 吴晓平；

【作者基本信息】 解放军信息工程大学 ， 大地测量学与测量工程， 2008， 硕士

【摘要】 时间作为基础物理量,在各领域中都有十分重要的意义。高精度的时间比对技术是实现高精度时间系统的关键,也是建立卫星导航定位系统的重要技术基础之一,直接影响系统导航、定位以及授时精度。本文围绕卫星导航定位系统中高精度时间同步算法进行了系统地研究和探讨,主要内容如下:1.简要回顾了时间同步技术在国内外的发展历程,论述了本论文研究的理论意义和实际应用价值。2.推导了星地无线电双向时间比对法的基本计算模型。根据星地无线电双向时间比对法的基本原理,详细推导了该方法在地心惯性系中精确到卫星和地面站速度的二次幂以及加速度的一次幂的计算模型。3.计算分析了星地无线电双向时间比对法基本计算模型中距离改正项时延对星地间相对钟差的影响量级。当采用GEO、GPS、GLONASS、Galileo卫星与地面站之间进行时问比对时,计算了模型中距离改正项时延对星地间相对钟差的影响量级,总结了在1ns和1ps的计算精度下分别需要考虑距离改正项中哪几项时延对星地间相对钟差的影响。4.分析总结了各主要误差源对星地无线电双向法时间比对的影响。分析了主要误差源对时间比对结果的影响,总结了在不同的精度要求下各主要误差源需要达到的精度。5.推导了Sagnac效应的计算模型。在卫星共视法时间比对中,以GEO、IGSO、MEO卫星为例,当地面站在赤道上和不在赤道上时,推导了这三种类型卫星在地心惯性系中Sagnac效应的具体表达式,编制了Sagnac效应的计算软件。6.总结了其它几种相对论效应对时间传递的影响。总结了引力频移、时间膨胀、偏心率效应等其它几种相对论效应对时间传递的影响。7.分析比较了几种时间预报模型的钟差预报效果。针对四颗不同时期发射的GPS卫星的卫星钟,对多项式模型、切比雪夫多项式模型以及灰色系统模型的短期、中长期钟差预报效果进行了分析和比较。更多还原

【Abstract】 As a basic physical variable, time has very important meaning in every field. The technology of time comparison in high precision is the key in the realization of high precision time system, and it is also one of the important technologies in constructing the satellite navigation and positioning system, and it affects the precision of navigation, location and time transfer of the system directly. Then the high precision time synchronization method in satellite navigation and positioning system is systematically studied and discussed in this paper. The main works are summarized as follows:1. The history of the technologies of time synchronization development at home and abroad is simply reviewed, and the theoretical meaning and practical application of this paper are dissertated.2. According to the principle of the method of two-way satellite-ground time comparison by wireless radio, the computation model in the ECI frame, which is expanded to the second order of the velocity and the first order of acceleration of satellite and ground-station, is derived.3. When having time comparison between the GEO, GPS, GLONASS, Galileo satellites and the ground-station, the influences magnitude of distance correction time delay in the computation model of the method of two-way satellite-ground time comparison by wireless radio on the relative satellite-ground clock bias have been computed and analyzed, and the influences of the items of distance correction time delay on the relative satellite-ground clock bias that should be accounted for are summarized in the 1ns and 1ps computation precision.4. The influences of the main error sources to the method of two-way satellite-ground time comparison by wireless radio are analyzed and summarized, and the quantity levels that the error sources should reach are also summarized in different precision demands.5. The detailed expressions of the Sagnac effect on GEO, IGSO, MEO satellites in the ECI frame are formulated when the ground-station is on the equator and the inverse aspect in the method of satellite common-view time comparison. The software of the computation of Sagnac effect is worked out.6. The influences of the other relative effects on time transfer, such as the gravitational frequency shift, time dilation, eccentricity effect, and so on, are also analyzed and summarized.7. Some basic models, such as the polynomial model, the interpolation model with Tchebytchev polynomials, and the gray system model, which are used to predict the clock bais of atomic clock in short- medium- and long-term, are discussed and analyzed, using four satellite clocks which were launched at different times.更多还原