采用延时积分的MSK软判决解调方法  

A Novel Soft-decision Demodulation Method with Time-delay Integration for MSK Signals

作　　者：闫涛[1] 张大鹏 陶祁[1] 

机构地区：[1]空军第一航空学院航空电子工程系 [2]解放军95883部队

出　　处：《电讯技术》2015年第3期275-278,共4页Telecommunication Engineering

摘　　要：针对最小频移键控(MSK)信号的软信息计算,提出了一种采用延时积分的软判决解调方法。该方法建立在MSK延时判决解调方案的基础上,按照条件概率理论的推导结果,使用接收已调信号同相分量和正交分量积分度量的乘积来表征原二进制信息码元的对数似然比信息,并以此作为MSK信号的软判决输出。分析与仿真结果表明,该方法简单方便,具有较大的通用性和灵活性,在Turbo联合MSK的编码调制系统中应用可以获得较为优异的抗噪声性能。A novel soft-decision demodulation method is proposed for the soft information computation of minimum shift keying（MSK）. The new method can be considered as the improved time-delay-decision de- modulation scheme. With this method, the log-likelihood ratio of each information bit is computed by the product of in-phase and quadrature component of MSK signal according to deduction from the theory of conditional probability and the log-likelihood ratio is taken as soft output of MSK. Analysis and simulation re- suits indicate that the proposed novel method can achieve better noise suppression performance in Turbo coded MSK system,and it is applicable to other coded modulation systems because of its easy implementation.

关 键 词：编码调制系统 最小频移键控 延时判决解调 对数似然比 软信息 抗噪性能 

分 类 号：TN919.7[电子电信—通信与信息系统]