船载卫通站大地指向精度对跟踪性能的影响分析

Analysis of the effect to the tracking capability of maritime satcom station by precision of antenna ground balance

某次海上作业过程中,船载卫通站自跟踪状态下天线跟踪接收机出现"跳大数"失锁现象,导致通信业务中断。结合不同数据源条件下跟踪接收机"跳大数"时刻天线控制单元(ACU)记录的数据,分析研究发现,导致"跳大数"失锁的原因是误差电压发散超出自跟踪门限值。以此为基础,对不同数据源下的采样数据进行分析,通过单一和交叉数据源的方式,将采样数据代入天线角度变换公式中,得出最终命令角度。对角度数据进行分析,得出不同数据源下的角度变换对大地指向的影响。在地理角和甲板角的正反变换中,如果数据源提供的数据精度存在差异,将导致天线由记忆跟踪进入自跟踪时偏离原位置过大,容易造成天线失锁。修改当前程序中数据源选择模块,使得程序在大地指向角度转换时采用最优数据源组合,规避了跟踪接收机"跳大数"失锁风险。

An offshore operation process, there was a phenomenon that the error voltage of tracking receiver overflows phonily, which resulted in the unlock of antenna and the interrupt of communication. Moreover, according to the analysis of data, we found the cause of the error voltage spread beyond the tracking threshold method. On this basis, analyze the sampling data of different data sources, by means of single and cross data source, the sampling data generation into the antenna Angle transformation formula, the final command Angle are obtained. Analyze the Angle data, it is concluded that under the different sources of perspective transformation to point to the influence of the earth. In geography Angle and deck Angle of positive and negative conversion, if the data source to provide the data precision of differences, will lead to the antenna by memory tracking when entering the tracking deviation from the original position is too big, easy to cause the antenna failure. Modify the current data source selection module in the program, making the program when the earth pointing Angle conversion using the optimal combination of data sources, avoid the tracking receiver risk of loss of lock.