一种适用于卫星导航系统星间链路的可抢占时隙TDMA体制

A Timeslot Seize-Able TDMA Technique for Satellite Navigation System with Crosslinks

针对传统TDMA体制数据传输时延较大的缺点,提出了一种适用于卫星导航系统星间链路的可抢占时隙的TDMA体制,并抽象出了该TDMA体制下的时隙编排优化目标,结合卫星导航系统星座的星间可视性,以顶点着色为理论基础提出了一种优化的时隙编排算法。仿真结果表明,与GPS星间链路的TDMA体制相比,所提出的TDMA体制可达到相同的卫星自主定轨精度以及系统用户等效观测误差(URE)性能,同时大幅提高了系统通信性能。

A new TDMA technique is introduced into inter-satellite network of satellite navi- gation system, which allows a satellite to seize the timeslot of another satellite. The delay of waiting for transmitting signal is reduced significantly comparing with the traditional TD- MA. The optimum object of timeslot assignment is formulated for the new TDMA tech- nique. According to the inter-satellite visibility of the navigation constellation, an algorithm is proposed to achieve the object of the timeslot assignment based on the vertices coloring theory. The simulation results show that the communication system is improved significantly by the new TDMA technique without influencing the satellite obit determination and URE performance comparing with the TDMA adopted by GPS.