【摘要】 为实现扩频通信系统中收发端伪随机序列的同步,研究了延迟锁相环的应用;针对其存在跟踪小信号速度慢、到达稳态时间长等问题,提出了归一化的处理方案,结果表明:当外界信号强度发生变化时,归一化处理可使送入载波环的信号电平稳定,码环也能保持稳定跟踪.对于发展中的OFDM通信系统,在对载波信号采用循环前缀相关性估计实现同步的基础上,也引入了延迟锁相环,并给出了实现同步的方法,进而克服了码间干扰和信道间干扰.2个系统的延迟锁相环算法均具有准确度高、信噪比低等优点.更多还原

【Abstract】 In order to achieve the synchronization of the receiver and the transmitter in spread spectrum system, this paper discusses the application of delay phase locked loop Aiming at the slow speed of track small signal, the long time to stable state etc., we put forward the normalization scheme, and results show that: when the outside signal is changing, normalization can make the signal level of the carrier wave loop more stable, and keep the track of code loop more stable, too. For the developing OFDM communication system, based on the estimation of circulative prefix relativity to achieve the synchronization, the delay phase locked loop is introduced. We also put forward the method of achieve synchronization realization, and the intersymbol interference and interference in the channel can be overcome. The two systems are highly accurate and low in signal-noise ratio .更多还原