遥感卫星自适应编码调制技术

Adaptive Coding and Modulation for Remote Sensing Satellite

文章首先针对遥感卫星数据传输中存在的问题,提出了自适应数据传输的概念;然后建立了遥感卫星动态信道模型,并在此基础上对自适应编码调制(ACM)技术在遥感卫星数据传输中的应用进行了详细分析,仿真验证了自适应系统与非自适应系统相比在数据传输中性能的提升,结果表明基于动态信道模型的信噪比估计方法使得系统性能提升效果显著,传输的数据量是非自适应系统的8.14倍,可有效解决系统资源浪费问题,最后对影响ACM性能的因素进行了分析,信噪比估计误差和延时对系统性能影响很大,移位门限技术可以有效的降低信噪比估计误差对系统性能的影响,而延时则需要对信道状态的预测来减小其影响。

In this paper,the concept of adaptive data transmission is put forward aiming at the problems existing in conventional remote sensing satellite data transmission; The dynamic satellite channel model is established,and the adaptive coding and modulating remote sensing satellite data transmission is analyzed in detail. The simulation results verify that the performance of adaptive system is much better than that of the non-adaptive system in the data transmission system. The way of SNR estimation based on the dynamic satellite channel model can improve the system performance remarkably. The quantity of data transmission is about eight times than that of non-adaptive system. It can effectively resolve the inefficient cost problems in conventional remote sensing satellite data transmission. At last the factors impacting ACM performance of SNR estimation error and delay are analyzed. The technology of shifted thresholds can remarkably reduce the influence of SNR estimation error towards the system performance. However,it needs to reduce the impact for delay on system performance by predicting the channel state.