二相编码信号载频盲估计快速算法研究

讨论二相编码信号载频盲估计快速算法.在没有接收信号先验知识的情况下,首先粗略估计出二相编码信号的载频(fc)和3 dB带宽(△f3dB),然后以(fc)为中心,以4(△f3dB)为带宽对BPSK信号滤波,再对滤波后信号平方得到一个准正弦波信号,估计出该信号的频率,最后将该频率除以2就得到BPSK信号的载频精确估计值.理论分析证明本算法的合理性,并给出算法的应用门限.仿真结果表明本算法在没有先验知识的情况下可以对BPSK信号载频进行精确估计,特别是在低信噪比条件下依然能够取得良好的估计性能,且本算法简单易行,运算量小,适合实时处理.

A research of fast algorithm for blind estimation of BPSK signal carrier frequency

A fast algorithm for blind estimation of binary phase shift keying(BPSK) signal carrier frequency was discussed.The carrier frequency and 3dB bandwidth were coarsely estimated without any prior knowledge of the received signal,and the estimation result fc and Δf3 dB were obtained.Consequently the BPSK signal was filtered with the center frequency fc and the bandwidth 4Δf3 dB.Then the filtered signal was squared,and a quasi-sinusoidal wave was obtained.Finally,the frequency of the quasi-sinusoidal wave was estimated,and half of the estimation value was the accurate estimation of BPSK carrier frequency.Analysis proved the rationality of the algorithm,and the application threshold was supplied.The simulation results showed that this algorithm could accurately estimate the carrier frequency of BPSK signal without any prior knowledge.Especially in low signal to noise ratio(SNR),the performance of the algorithm was still favorable.This algorithm was simple and the computational complexity was low,and it was convenient to be realized real-timely.