机载雷达高度计对海况及海面风速的测量研究

STUDY ON MEASUREMENT OF SEA STATE AND SEA SURFACE WIND SPEED BY AN AIRBORNE RADAR ALTIMETER

运用我国自行研制的ZHG－1型X波段机载雷达高度计于1995年4月13日-4月18日在青岛附近海域进行的海上飞行实验数据，及导出的均方根波高、有效波高、均方根波陡算法模型，得到了上述海况参数值。又利用高度计海面回波波形下降沿数据计算出海面风速，结果与实际情况符合。最后对ZHG—1型机载雷达高度计测量分辨率进行分析。

The paper reports use of experimental data obtained by a ZHG-1 airborne altimeter over the Qingdao' adjacent sea area, China (in April, 1995) to derive the algorithm for calculating rms wave height, sighficant wave height, and rms wave slope. A new algorithm for getting the sea surface wind speed from the return waveform instead of the scatter coefficient was also developed. The calculation results showed the precision and accuracy were 18.0cm and 4.7cm for rms wave height, 25.4cm and 5.0cm for sitwficant wave height respectively, and that the rms wave slope and its precision were 0.09 and 0.01 respectively. Considering the the rms wave slope includes the capillary Wave slope in addition to the gravity wave slope the result was reasonable. The sea suface wind speed and its accuracy from the altimeter data was 1.5m /s and 0.4m /s respectively. The wind speed was not consistent with the in situ measurement data, but this discrepancy was mainly due to the not full development of the ocean waves because of the NNW wind direction. The derived algorithms was used to get the measurement resolution of the rms ocean wave height as where h is the rms ocean wave height and △h is the resolution of h. In this experiment △h measured by the ZHG-1 airborne altimeter was 44.1cm.