Research On Satellite Time Service Receiver And Testing System

As a new timing technology, satellite time service can effectively reduce the error caused by geometric factors and achieve precise timing on a global scale, so it has become the mainstream method in the time synchronization field. The satellite receiver is a connector between satellite and ground users. Its performance will directly affect the reliability of time service system and determines the competitiveness of the satellite system as a key component.Aim to provide domestic application of satellite time service using Beidou satellite systems, this thesis studies on the performance optimization and testing technique of a satellite time service receiver. The main work includes two parts, the design of time reference source based on rubidium atomic frequency and the testing system of satellite time service receiver.(1) In order to improve the timing precision and stability of satellite receiver, the atomic frequency standard, which is the most accurate and stability among all the standard equipment, is adopted instead of quartz crystal oscillators,thus helps to reduce the receiver clock error and optimizes the accuracy and performance of the receiver. According to the operating principle, control methods and frequency characteristic of the rubidium atomic frequency standard X72, the thesis designs the data communication, signal output and expansion, frequency adjustment, alarm and other auxiliary hardware modules. The PCB circuit board for the whole time reference source is finished and the equipment calibration and maintenance method are given briefly.(2) The testing system provides a measure for controling and optimizing the quality of the satellite receiver. According to the specific requirements, a software design scheme for the testing system is proposed. Data communication module, which accomplishes real-time data monitoring and alarm on faults, is realized using C++ Builder software. Combing with a database, the test system can storage and playback information of testing results between the receiver and computer massively. The testing system can carry on comprehensive analysis of the dynamic performance, long-term stability of the receiver,improve the efficiency of the receiver data analysis, as well as record more accurate running status and working conditions of the receiver.The performance characteristics of the proposed time reference source has been tested, its frequency accuracy is±5×10^-11. The device satisfies harsh technical requirements and has practical application values. The testing system can be utilized for real-time testing and monitoring of the dual-mode satellite timing receiver. It plays a key role in performance analysis and fault location in the production process, which effectively reduces labor intensity of the testing workers.