Research On High-precision Baseline Resolution Algorithm Of GPS/COMPASS Combination

With the increasing popularity of the satellite technology, global navigation and positioning satellite system has become the main way for positioning.Nowadays,four global navigation satellite systems:the U.S. GPS, the Russian GLONASS, the EU’s GALILEO under construction, and our second-generation Beidou Navigation Satellite System (Compass). The data processing is a key element of GNSS positioning technology, can be divided into two stages comprised of baseline solution and network adjustment. The time is occupied longest by baseline solution as the base of network adjustment and the workload is the largest in GNSS processing. The quality of baseline solution has a direct impact on the positioning accuracy and reliability of the GNSS network.The using-permissions and observing conditions of independent satellite navigation system’s positioning accuracy are limited, so the accuracy, security, reliability and availability of providing satellite positioning sometimes can not be fully guaranteed, even difficult to meet the requirements of the navigation and positioning.However,a combination of multi-constellation can solution this problem,greatly increase the number of visible satellites, reduce the the dilution factor of accuracy, consist a better geometric distribution, provide the possibility of improving positioning accuracy, and have a very important significance to the high-precision positioning.Recently, research on high-precision baseline resolution algorithm of GPS/COMPASS combination is limited to the stage of theoretical discussion, this paper first analyzes Beidou satellite broadcast ephemeris of three tracks, and develop a common set of satellite coordinates calculation program according to the difference of the orbital ephemeris, and achieve the unity of coordinate system and time system of GPS and Compass. The high-precision baseline solution is based on a high-precision carrier phase observations, because of observing environmental reasons, it is likely to cause the observed datas arise cycle slips, this paper first analyzes the nature of the the Beidou carrier phase observation data, and then develop a more comprehensive program for Beidou-data cycle slip detecting and repairing. On this basis, a set of high-precision baseline resolution algorithm suitable for this model is developed according to the mathematical model of constructed baseline solution of GPS/Beidou combination.The research for GPS/Compass combination of high-precision baseline solver technology will be widely used in various fields of engineering measurements, from the common control measurement (such as urban control network engineering control network and mapping control network) to precision engineering measurement,has shown great advantages, has a very real and important significance for China’s disaster prevention, mitigation and disaster prediction.