基于汉宁窗的插值FFT算法在11号数据链测频中的应用

Application of Link11 Measuring Frequency Based on Hanning Window Interpolated FFT Algorithm

测频技术作为研究Link11数据链接收系统的关键技术,怎样准确获取频率值对多普勒频移的校正以及各数据单音频率的准确获取都有着重要意义。目前,作为测频的主要技术手段,运用快速傅里叶进行频域分析时会不可避免地产生栅栏效应,降低了测量精度。为提高测量精度,这里提出了一种基于汉宁窗的频域插值算法。仿真结果表明,该算法在降低计算量的同时极大地消除了泄漏效应,提高了测频精度。

As the key technology of the Link11 receiving system,the frequency measurement technology is very important for correction of doppler shift and the accurate acquisition of single tone frequency. At present,as the main technical means of frequency measurement,using FFT for frequency domain analysis maybe lead to spill（or leakage）effect is inevitable,which may produce somewhat erroneous result. To solve this problem, a frequency-domain interpolated algorithm is presented based on Hanning window. The simulation results show that this algorithm not only reduced computation,but also greatly eliminates the leakage effect and improves the precision of the measurement.