探空火箭通信系统最优信噪比切换阈值的设计  

Design of the optimum signal-to-noise ratio switch threshold of sounding socket communication system

作　　者：陈萍[1,2,3] 熊蔚明[1] 于世强[4] 陈志敏[1] 

机构地区：[1]中国科学院空间科学与应用研究中心,北京100190 [2]中国科学院大学,北京100049 [3]中国船舶工业系统工程研究院,北京100036 [4]中国空间技术研究院载人航天总体部,北京100094

出　　处：《固体火箭技术》2015年第4期595-600,共6页Journal of Solid Rocket Technology

基　　金：国家863项目(2011AA7033045)

摘　　要：结合Nakagami衰落信道模型,分析了探空火箭飞行过程中经历的瑞利信道和莱斯信道的特性,以BPSK、QPSK、16QAM、64QAM 4种调制方式结合的可变调制传输系统为例,提出了可根据地面数据接收站天线的不同仰角,计算最优信噪比切换阈值的方法。最优信噪比切换阈值在满足误码率指标的前提下,使系统的数据吞吐量最大。进一步比较了采用最优信噪比阈值与采用BPSK固定调制方式、恒定误码率信噪比阈值的吞吐量差异,结果表明,采用最优信噪比阈值法得到的数据平均吞吐量分别是另外2种方法的3.89倍和1.043倍。其结果为可变调制技术在探空火箭工程中的应用提供参考依据。Combining with Nakagami fading channel model,Rayleigh channels and Rician channels were analyzed between sounding rockets and ground station during the flight course. It takes an example of a variable modulation system with four types of modulations,including BPSK,QPSK,16 QAM and 64 QAM,and proposes a method to acquire the optimum signal-to-noise ratio switch threshold,according to different elevation angles of ground receiving station. The optimum threshold could maximize the throughput,while satisfying BER goal. Furthermore,the paper analyzes and compares the throughput difference with optimum signalto-noise ratio switch threshold,BPSK modulation method and constant-BER signal-to noise ratio threshold. The results show that,by adoption of the optimum threshold,system throughput is 3. 89 times and 1. 043 times higher than the other two methods,respectively. The results could provide reference and basis for the application of variable modulation technology into practical sounding rockets projects.

关 键 词：可变调制 最优信噪比阈值 探空火箭 

分 类 号：V556[航空宇航科学与技术—人机与环境工程]