串行直扩MSK调制信号产生及FPGA实现

摘要

鉴于常规并行直扩MSK调制器的硬件实现占用资源较大且在高数率场所实现困难,研究了一种直扩MSK信号串行产生方法,并通过硬件实现证实了该方法的可行性和优越性.串行产生方式是将直扩BPSK信号经过转换滤波器作用后得到直扩MSK信号,算法核心在于转换滤波器的设计,具体方法为采用凸优化算法设计出的滤波器具有较小的阶数,使得硬件实现占用资源较少.结果表明,在低速率条件下两者输出的直扩MSK信号性能一致,而串行方式硬件复杂度小得多;在高速率条件下并行方式实现困难,而串行方式能更好地适用于高速率的直扩系统.%The resource of direct sequence spread spectrum (DSSS) MSK signal on the hardware system is very big,which uses conventional parallel generation method,and DSSS MSK signal is hard to be implemented in high rate system.Thus,a serial of DSSS MSK signal generation method was studied on,it confirmes the feasibility and superiority of this method through the hardware implementation.The serial DSSS MSK signal was formed by putting the spread spectrum BPSK signal into a transformed filter.Thus,building an appropriate transformed filter (TF) became the crux of algorithm.A method of convex optimization was used to build TF,and the filter of this method has smaller order and is less resource consumed.The results showed that the output properties of the two MSK signal were the same under the condition of the low rate,but the hardware complexity of serial signal was much less.The parallel MSK signal has more implementation difficulties under the condition of high speed,but the serial mode can be better applicable to the high rate of spread spectrum system.