中频雷达风场的双谱分析

对中纬度中频雷达１９９７年６月８２ｋｍ高度的小时平均风场数据进行了动态谱分析和双谱分析，得到了中层顶区域谱行为具有多样性和各向异性的特点，以及行星波，潮汐波和重力波之间相位相干的现象，讨论了中层顶行星波，潮汐波和重力波之间存在非线性相互作用的可能性。

BISPECTRAL ANALYSIS OF THE MF RADAR WINDS

Bispectral analysis and dynamic spectral analysis are applied to the wind data of June, 1997, measured by MF radar in Yamagawa, Japan, to investigate nonlinear interactions among planetary waves, tidal waves and gravity waves in the mesopause region. Results show that there were strong diurnal tide, semi-diurnal tide and quasi-two-day wave activities, and some groups of three waves whose frequencies satisfied resonant conditions coexisted and their phases were coherent, which may suggest non-linear wave-wave interactions. Discussions on these nonlinear interactions between different kinds of waves are presented.