FM信号数字化解调算法的改进与实现  

Improvement and realization of digital demodulation algorithm for FM signals

作　　者：刘立[1] 向新[1] 孙晔[1] 王锋[1] 

机构地区：[1]空军工程大学工程学院,陕西西安710038

出　　处：《光通信研究》2012年第4期26-28,63,共4页Study on Optical Communications

基　　金：陕西省自然科学基础研究资助项目(2009JM8001-4);航空科学基金资助项目(20095596014)

摘　　要：针对FM(调频)信号数字化解调中叉积鉴频法存在占用资源大、精度低和只适用于窄带信号解调的缺点,采用了一种改进的解调算法,该算法通过改变对I路和Q路信号的处理方法,避免计算近似反正切值,最大限度降低了算法复杂程度,实现了占用资源小、精度高和满足窄带和宽带信号的解调。经MATLAB软件仿真并利用Quartus II 11.0软件基于Cyclone III芯片设计仿真,验证了该算法是可行的。In view of the disadvantages of the cross product frequency discrimination method for FM signal digital demodulation, such as excessive occupation of hardware resource, low accuracy and limited application to narrowband signal demodulation on- ly, this paper adopts an improved algorithm, which avoids computing the approximate the inverse tangent value and reduce to the maximum the algorithm complexity by changing the processing of the signals in I and Q channels, thus realizing the demod-ulation with less occupation of resource, higher accuracy and suitability for both narrowband and broadband FM signals. Simu-lation by Matlab and implementation on the platform of Quartus Ⅱ 11.0 software based on the Cyclone Ⅲ chips verify the feasi- bility of this algorithm.

关 键 词：数字化解调 多相滤波 正交变换 现场可编程门阵列 

分 类 号：TN76[电子电信—电路与系统]