FQPSK和SOQPSK信号的通用准最优解调设计  

A general quasi-optimal demodulation design for FQPSK and SOQPSK

作　　者：郄志鹏[1] 翟海涛[1] 钟声[2] 朱江[1] 

机构地区：[1]国防科技大学电子科学与工程学院,湖南长沙410073 [2]中国工程物理研究院电子工程研究所,四川绵阳621900

出　　处：《国防科技大学学报》2014年第4期77-81,共5页Journal of National University of Defense Technology

基　　金：国家自然科学青年基金项目(61201166);国家自然科学基金项目(61101097)

摘　　要：FQPSK-JR和SOQPSK-TG是IRIG-106遥测标准中可以互换的两种信号体制,两种信号有着近乎相同的功率效率和带宽效率。尽管两种信号都可以采用常规的OQPSK接收机进行解调,但是基于OQPSK结构的接收机忽略了两种信号固有的记忆特性,其解调性能损失相比最优解调达2dB之多。在遥测链路中,受设备体积及电源限制,2dB的功率损失是至关重要的。虽然基于其调制体制相对应的最优接收机都能提高功率效率,但信号产生体制的不同导致了其对应的最优接收机结构不同。将IRIG-106标准中的FQPSK-JR信号用CPM调制来近似表示,将SOQPSK-TG信号的频率成型脉冲进行了截短近似,设计了基于CPM的通用准最优解调器。基于CPM近似设计出的解调器与OQPSK解调器一样无须对两种信号进行识别,仿真表明基于CPM设计的通用解调器对两种信号进行解调的渐进损失都很小,对复杂度也进行了分析对比。According to the IRIG-106 telemetry standard, FQPSK-JR and SOQPSK-TG are two interchangeable signals, which have ahnost the same power efficiency and bandwidth efficiency. The two signals can be demodulated by the universal receiver of OQPSK. The optimal performance degradation of the symbol by symbol demodulation based on the OQPSK structure can reach 2dB while its optimal demodulation may ignore the two signals＇characteristics of memory. The 2dB power loss is crucial in the telemetry link for the limit of equipment size and power. The optimum receivers based on their modulation schemes can improve the power efficiency, but the different system of signal generating will lead to different structure of corresponding optimal receiver. In this research, the FQPSK-JR signal in IRIG-106 standard was approximated by CPM modulation, the SOQPSK-TG signal was truncated for an approximate analysis. The result of simulation showed that the signals demodulated by the CPM-based demodulator and by the OQPSK-based demodulator display the same function of little with incremental loss, and demand no need to do signals recognition. In addition, the implementation complexity was also taken into account.

关 键 词：FQPSK-JR SOQPSK-TG IRIG-106 连续相位调制 

分 类 号：TN311[电子电信—物理电子学]