数据采集与处理2013，Vol.28Issue(2)：160-165,6.
全相位FFT测相方差及其Cramer-Rao下限
Variance of All-Phase FFT Measuring Phases and Its Cramer-Rao Lower Bound
摘要
Abstract
To disclose the underlying reasons of the superiority of apFFT in measuring phases compared with other existing methods, the distribution characteristics of spectral leakages and the theory of parameter estimation are combined. Therefore, one Cramer-Rao lower bound (CRLB) involving two- unknown- parameter estimation is deduced, which is suitable to apFFT measuring phases. Based on the deduction, the relationship of apFFT phase error and frequency offset distribution is also obtained. Moreover, it is also pointed out that the novel CRLB is 12 dB lower than the traditional CRLB involving three parameters. Consequently, several conclusions are drawn for apFFT measuring phases under different signal to noise ratios (SNRs) and different frequency offsets. Simulation results indicate that the phase measuring variance of apFFT can be defined by CRLB2 with different SNRs and different frequency offsets, verifying the above conclusions and the correctness of the novel CRLB.关键词
全相位FFT/相位测量/克拉美罗下限/频偏/谱泄漏Key words
all-phase FFT/ measuring phase/ CRLB/ frequency offset/ spectral leakage分类
信息技术与安全科学引用本文复制引用
黄翔东,王博,杜宇彬,王兆华..全相位FFT测相方差及其Cramer-Rao下限[J].数据采集与处理,2013,28(2):160-165,6.基金项目
国家自然科学基金(61271069)重点资助项目 （61271069）
国家重点基础研究发展计划("九七三"计划)(2010CB327806)资助项目. （"九七三"计划）
