CAJ | 학술논문

针对PCM/FM系统中多数同步方法都需要在接收端添加额外的软件代价比较大的特点,基于多符号检测（MSD）的PCM/FM信号软件化解调系统,研究了一种基于MSD的迟早门载波同步和升降频码同步方法。利用MSD自身的优势,就地取材,简单地对本地时延和频偏进行加减即可达到同步要求。详细研究了低信噪比环境下,可变步长的时频同步方法,仿真了几种指标之间的关系。在系统代价较低的情况下保证了同步的快速实现。
침대PCM/FM계통중다수동보방법도수요재접수단첨가액외적연건대개비교대적특점,기우다부호검측（MSD）적PCM/FM신호연건화해조계통,연구료일충기우MSD적지조문재파동보화승강빈마동보방법。이용MSD자신적우세,취지취재,간단지대본지시연화빈편진행가감즉가체도동보요구。상세연구료저신조비배경하,가변보장적시빈동보방법,방진료궤충지표지간적관계。재계통대개교저적정황하보증료동보적쾌속실현。
Most synchronization methods of PCM/FM system need to add additional software in the receiver,the cost becomes higher.Aiming at this char acteristic,in the PCM/FM signal demodulation system based on MSD,an early-late gate carrier synchronization and lift frequency code synchronization method base d on MSD is studied.By utilizing the advantages of MSD,the synchronization requi rement can be achieved by adding and subtracting local time delay and doppler fr equency shift.A variable-step time-frequency synchronization method is studied en detail in the low SNR environment,and the relationship between several speci fications is simulated.This method ensures rapid implementation of synchronizati on with low system cost and it has some engineering application value.