摘要
提出一种新的基于频域的相位差分法,能通过多次等比延时的FFT变换,得到多个时间点相位信息,再利用前后各时间点的相位关系来消除相位模糊的问题;定量分析了FFT计算点数和变换次数以及环境的信噪比3种因素,对测频性能的影响,并得出测量误差的理论表达式。通过大量仿真结果表明,该方法的测量精度受FFT的计算点数和环境信噪比影响较小,而受FFT变换次数影响较大;因此该算法不仅稳定性好、测量精度高、对环境的依赖很低,而且计算量较小、便于硬件实现。
A new kind of frequency estimation algorithm based on phase difference is proposed. Many times of fast Fourier transformations by geometric delay are used to resolve the problem of phase ambiguity. The influence of the length of FFT and times of transformation to the frequency estimation accuracy under the different frequency range is researched. A great deal of simulation shows that the new algorithm not only has nice frequency stability and good frequency estimation accuracy, but also has has smaller computational amount which can be utilized for hardware implementation of the receiver system.
出处
《电子测量技术》
2015年第1期25-28,共4页
Electronic Measurement Technology
关键词
相位差分
相位模糊
测频精度
phase difference
fast Fourier transform
phase ambiguity
frequency estimation accuracy
