摘要
分析了HDL数据链发信机设计中的几种GMSK调制方法;阐述了用PLL两点调制的必要性,进而给出了基于PLL的GMSK两点调制的模型。同时,对非线性模型进行线性化等效,列出它们的闭环传递函数,并通过Matlab仿真波形来观察频率响应曲线;最后对调制系统进行ADS仿真,分析系统的收敛性,通过时域、频域调制波形分析,得到最优系统参数。
First, several methods of GMSK modulation in HDL design of the transmitter are analyzed and the necessity of the usage of two-point modulation based on PLL is described in this paper. Then, a non-linear PLL model is linearized with equivalency and also their closed loop transfer functions are listed. Finally, after the simulation with matlab sottware and ADS simulation, the optimum parameters in the two-point system are obtained through analysis of the system convergence and the modulation waveform of time-domain and frequence-domain.
出处
《航空电子技术》
2008年第1期9-13,共5页
Avionics Technology
基金
上海市科技发展基金资助项目(项目编号065115016)
