GEO移动通信卫星多波束天线指向测量与精度分析

摘要

In this paper,the multibeam antenna pointing measurement for geostationary mobile communications satellites is discussed.Based on amplitude comparison monopulse principle,a maximum likelihood estimation of the antenna pointing is given.The estimation gives the pointing measurement precision and error distribution.The pointing error is composed of calibration error and estimation error,while the pointing error follows normal distribution.Simulation results show that the precision improvement slows down and the precision mainly depends on the calibration error when SNR is greater than 20 dB.Moreover,it is largely affected by channel stability when the uncertainty is greater than 1 dB（σ） in the simulation.%讨论了地球静止轨道移动通信卫星多波束天线指向测量问题。基于比幅单脉冲原理,给出了天线指向测量的最大似然估计方法,并分析了该方法的测量精度和测量误差分布,指出测量误差的构成包括系统定标误差和估计误差,误差分布服从正态分布。仿真结果表明,当信噪比高于20dB时,测量精度随信噪比增大的改善变缓,此时精度主要取决于定标误差。当通道不确定性高于1dB（σ）时,测量精度受通道稳定性影响显著。