星基AIS信号解调算法性能分析  

Performance analysis of demodulation algorithms for satellite-based AIS signals

作　　者：吴川隆[1] 初翠强 王翔[1] 姜文利[1] 柳征[1] 

机构地区：[1]国防科技大学电子科学与工程学院 [2]中国人民解放军61541部队

出　　处：《航天电子对抗》2015年第4期6-9,共4页Aerospace Electronic Warfare

基　　金：国家自然科学基金资助项目(61401490)

摘　　要：星基AIS采用非合作式通信方式,具有覆盖范围广、通信距离远等特点。为了考察现有算法对星基AIS低信噪比、强干扰信号等复杂工作环境的适应能力,从低信噪比环境、抗干扰能力等四个方面对1比特差分(1D)解调算法、2比特差分(2D)解调算法、1+2比特联合差分反馈(1+2DF)解调算法、1+2+3比特联合差分反馈(1+2+3DF)解调算法以及基于PSP的最大似然序列估计(PSP-MLSE)算法进行了性能分析。分析结果表明,PSP-MLSE算法抗干能力较强,能够更好地适应低信噪比和强干扰环境;1+2DF解调算法和1+2+3DF解调算法虽然抗干扰能力及适应低信噪比环境的能力相对较弱,但是能够容忍更大的中心频率估计误差,并且算法复杂度较低。分析结论对于不同的应用场合选用不同的解调算法有较好的指导意义。Satellite-based AIS,adopting the non-cooperative communication mode,has the characteristics of wide coverage and long communication distance.In order to adapt to the complicated space environments,demodulation algorithms for satellite-based AIS signals are discussed from different aspects,including low SNR,frequency estimation error,anti-interference ability,and so on.Simulation results show that the ratio of correct demodulation packages with PSP-MLSE is obviously higher than the differential demodulation algorithms,but has the higher complexity;1＋2DF demodulation algorithm and 1＋2＋3DF demodulation algorithm have lower complexity and endure the greater center frequency error.The conclusions have a good guidance significance to select corresponding demodulation algorithms for different applications.

关 键 词：星基AIS GMSK 差分解调 AMP 逐留存处理 

分 类 号：TN911.3[电子电信—通信与信息系统]