基于离散傅里叶变换的高动态突发信号检测及频率估计

摘要

针对高动态突发通信应用环境,提出了一种新的基于频率域的突发信号检测及载波频偏估计算法,通过一次离散傅里叶变换( DFT)实现突发信号存在性检测及频率估计,并与经典Power-Law算法进行了比较。仿真结果表明：在低信噪比条件下,新算法检测信噪比门限改善超过1 dB,频率估计均方根误差小于符号率的1‰,并且对载波频偏及信号电平动态不敏感,实现结构简单,适合实时处理及工程应用。%Considering the high dynamic features in burst transmission system,this paper presents a new al-gorithm of signal detection and frequency estimation based on frequency domain. This algorithm can per-form presence detection and frequency estimation through one discrete Fourier transform( DFT) operation of the received signal. Comparisons are made with the Power-Law algorithm. Simulation results prove that the signal-to-noise ratio(SNR) threshold is improved more than 1 dB when SNR is low,the root mean square error(RMSE) of frequency estimation is lower than 1‰ of the symbol rate,and the probability of detection and accuracy of frequency estimation is influenced little by the variation of power level and fre-quency offset. It is convenient for real time processing and engineering applications.