基于数据辅助的CPFSK信号的定时估计  

Data aided timing estimation of CPFSK signals

作　　者：沈文丽[1] 张屹[1] 赵民建[1] 仇佩亮[1] 

机构地区：[1]浙江大学信息与电子工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2007年第12期2026-2030,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(60602023)

摘　　要：针对连续相位调制(CPM)信号的突发模式传输系统,提出一种基于训练序列的符号定时估计算法,并分析定时估计误差的方差修改的Cramer-Rao限(modified Cramer-Rao bound,MCRB).在传输突发包前插入一段已知的训练序列,接收端将信号进行差分、求相位后,对其进行离散傅里叶变换(DFT).符号可以定时从DFT的一次谐波分量的相位中估算得到.Matlab仿真结果表明,在加性白高斯噪声(AWGN)以及瑞利平坦衰落信道上,该算法能快速准确地估计出初始定时偏差,适用于任何进制的CPFSK信号的非相干差分接收系统,并且在实际的软件无线电平台上得到验证.A novel data aided symbol timing estimation algorithm was proposed for the transmission systems of continuous phase modulation （CPM） signals in burst mode. The modified Cramer-Rao bound （MCRB） of the timing estimation error was also analyzed. A training sequence is embedded before transmission of each packet. The receiver calculates the phase of differential signals and discrete Fourier transform （DFT）. The symbol timing can be estimated from the phase of the first harmonic component of DFT outputs. Matlab simulation showed that this algorithm can estimate the initial timing error rapidly and accurately in the additive white Gaussian noise （AWGN） and the Rayleigh flat fading channels, and is suitable for noncoherent differential receiving systems of any M-ary continuous phase frequency shift keying （CPFSK） signals. The proposed algorithm was successfully testified on a software radio platform.

关 键 词：连续相位调制 定时估计 离散傅里叶变换 估计误差的方差 修改的Cramer-Rao限 

分 类 号：TN929.5[电子电信—通信与信息系统]