基于修正瑞利分布的S/Ka双频天线捕获概率分析

Capture probability of S/Ka band antenna based on modified Rayleigh distribution

为了满足星地链路间海量数据的传输需求,数据传输频段已由传统的X频段扩展到Ka频段。Ka频段卫星目标具有窄波束、高动态等特性,对地面接收系统的捕获跟踪性能提出了更高要求。针对Ka频段的不同工作模式,对捕获过程中天线跟踪精度、电轴一致性及搜索捕获范围等影响因素进行了分析,提出了一种近似为修正瑞利分布的捕获概率模型。仿真分析了不同影响因素对目标捕获的敏感性,总结了Ka频段捕获概率的性质。最后对某设备实际跟踪情况进行了验证分析,为有效提高Ka频段捕获跟踪能力提供了分析依据。

With the requirements of massive data transmission between satellite platform and ground sensors,the frequency band of data transmission has been extended from the traditional X band to Ka band.The Ka band satellite target with narrow beam and high dynamic puts forward higher requirements for the acquisition and tracking performance of ground receiving system.For different working models of the Ka band antenna,the influencing factors such as antenna tracking accuracy,electric axis consistency and search range in the capture process were analyzed.Then a capture probability model,which can be approximated to the modified Rayleigh distribution,was proposed.The sensitivity of different influencing factors to target acquisition was simulated and analyzed,and the properties of Ka band capture probability were summarized.Finally,the actual tracking of a certain device was verified and analyzed,which provides an analysis basis for effectively improving the capturing and tracking ability of Ka band antenna.