In order to know the feasibility that the modern spectrum analysis ways are applied in wind profiler, the fast Fourier transform (FFT) and maximum entropy method (MEM) are contrasted by using simulation data and radar measurement data respectively. The result shows: (l)When the radar echo is strong, the effect of two methods are equivalent. But when the echo is weak, the MEM spectra are better than others. The MEM can powerfully remove the ground clutter contaminant. (2)The MEM spectra are smooth, so it can be used to reduce white noise influence also. (3) The iterative steps in MEM have some influence on the spectrum. The step calculated by final prediction error(FPE)rule is less. Using 15 steps in MEM can get a better result. The wind profiler radar echo is weak usually, so the conclusions of this paper can help improve the effect of spectrum analysis.%为了解现代谱分析技术在风廓线雷达中应用的可行性,通过采用实测的和模拟的风廓线雷达回波信号,对比研究了FFT法与最大熵法的谱分析效果.结果表明:(1)当回波信号比较强时,两者都可以得到较好的谱分析效果；但是当回波信号较弱时,最大熵法分析效果优于FFT法,最大熵法对地杂波具有较好的抑制能力.(2)最大熵谱比较光滑,表明最大熵法对随机白噪声也有一定的抑制作用.(3)最大熵法的递推阶数对谱分析结果有一定影响,最终预测误差准则确定的递推阶数一般偏小,采用15阶的递推阶数进行最大熵法分析取得了较好结果.由于风廓线雷达回波通常都较弱,因此研究结果可望用于改善信号处理效果.
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