本文提出一种测频校正方法，该方法针对由50%数据重叠的短时傅里叶变换（STFT）实现、子信道数据采用自相关积累进行处理的数字信道化接收机，分析了子信道自相关使用单点延迟的必要性，研究了噪声数据的相关性对相位的影响，并利用噪声功率对相位测量值进行校正。使用校正后的相位计算信号频率，频率测量均值误差和均方根误差均减少。尤其在信噪比较低时，该方法能明显提高测频精度。仿真验证了该方法的有效性，且单个子信道只消耗一次加法运算，能够保证实时性。
A frequency measurement correction method was proposed, which is targeted at digital channelized receivers implemented by the short-time Fourier transform with 50% data overlap and sub-channel data accumulated using autocorrelation, analyzed the necessity of sub-channel autocorrelation using single-point delay, studied the effect of correlation of noise data on phase, and corrected the phase mesurements using noise power. Using the corrected phase to calculate the signal frequency, the mean error and root-mean-square error are reduced. Especially at low signal-to-noise ratios, this method significantly improves the frequency measurement accuracy. Simulation verified the effectiveness of this method.And only one addition operation is consumed fo a single sub-channel, which can guarantee the real-time performance.
2023,45(17): 145-148 收稿日期：2023-03-20
DOI：10.3404/j.issn.1672-7649.2023.17.028
分类号：TN957
作者简介：李琳(1992-),女,硕士,工程师,研究方向为数字信号处理
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