伪码辅助载波星间自主测距技术

A Pseudo-random Code-Aided Carrier-Based Inter-Satellite Autonomous Ranging Technique

提出了一种存在弱相对运动的卫星之间基于载波高精度自主相对测距技术,它借助伪码测距技术所得到的粗测距离和cm级测距精度选择载波频率,消除了载波测距中存在的整周模糊度问题,避开了复杂的整周模糊度求解算法;借助伪码高精度时间差测量技术,使不同卫星上面伪码和载波相位观测时间之差的测量精度(标准偏差)优于0.1ns,并使得星间钟差可忽略不计。最终测距3σ精度有基于伪码的cm级提高到了mm级。文中不仅分析了相对静止时卫星间的距离测量精度,而且分析了存在弱相对运动(相对运动速度不大于10m/s)时卫星间距离测量精度。理论分析和工程可实现性分析都表明:该技术切实可行且易于实现。

A novel inter-satellite autonomous ranging technique based on carrier is proposed in the case of weak relative motion.With the help of the pseudo-random code,a coarse range measurement value with low accuracy but without ambiguity can be gotten.The coarse measurements with low accuracy are used to select the carrier frequencies to make the carrier-cycle integer ambiguity vanish in case the carrier-based ranging is used.in case the carrier-based ranging is used.The proposed carrier-based ranging technique is used to measure the distance again and the measurement accuracy can reach to the millimeter-level from the centimeter-level reached by the code-based method.This paper analyses the measurement accuracy in both relative stationary and motional cases,and the results show this novel ranging technique is practicable and easy to be implemented.