软件无线电调制解调通用平台的设计与实现

软件无线电被认为是继模拟通信到数字通信、固定通信到移动通信之后无线通信领域的第三次突破。文章在研究软件无线电的基本结构的基础上从信号空间映射的角度对通信信号的调制解调进行了深入的研究，将已调信号表示为N维正交基函数的展开式，根据调制方式确定调制信号到N维信号空间的映射从而完成调制过程；同时引入空间距离的概念，根据调制映射关系，建立起多对一的最优信号检测理论。并且使用MATLAB编制了基于软件无线电结构的通信信号调制解调通用平台软件，实现了对各种调制解调模式的兼容。

The design of general platform software about modulation and demodulation with software radio

The software radio is thought to be the third breakthrough following the analogue communication to digital communication and fixed communication to mobile communication. In this paper, a deep research of modulation and demodulation of communication signal with the angle of signal space is given. The modulated signal can be expressed by N's dimension orthogonal base function. According to the defining modulation mode, the modulation process is accomplished. At the same time, it introduces the definition of spatial distance, and establishes a multi-point to one point optimal signal detection theory according to the relationship of modulation mapping. At last, this paper accomplishes the general platform software of communication signal modulation and demodulation using MATLAB, and realizes the compatibility of multi-mode modulation and demodulation.