两种快速频域细化分析方法的研究

Research of two kinds of fast zoom spectrum

在通信和其它的实际应用中,经常需要对信号的局部频谱进行细化分析。应用FFT算法可以快速得到信号的粗略频谱,但若要通过FFT直接得到细化频谱则计算量大大增加。因此可以从FFT的粗略估计频谱来获取需要细化分析的频谱范围,再用其它频域细化方法对其进行快速细化分析。分析了经典的频域细化方法CZT和Zoom FFT算法,并提出了一种改进的自适应抽取Zoom FFT频域细化算法。对这些算法各自的性能进行了详细的分析和比较,并通过仿真进行了验证。

To analyze the zoom spectrum in a narrowband of broadband signals, a fast algorithm is proposed that adopts FFT to obtain the coarse spectrum and the frequency range to be zoomed, and then further refines the interested narrowband by spectrum zooming methods. Two classical spectrum zooming methods, CZT and Zoom-TTT, are analyzed in depth, and an improved Zoom-FFT method is put forward based on the adaptive decimation. The performances of these methods are compared by analysis and simulation, and the results show that they are feasible to analyze the zoom spectrum.