A pilot needs operational information about wind over sea as well as wave height to provide safety of hydroplane landing on water. Near-surface wind speed can be obtained with an airborne microwave scatterometer radar designed for measuring the scatter characteristics of a surface. Narrow-beam antennas are applied for such wind measurement. Unfortunately, a microwave narrow-beam antenna has considerable size that hampers its placing on flying apparatus. In this connection, the influence of antenna beamwidth expansion on the result of measurement of the sea surface NRCS by a scatterometer (altimeter) having a nadir-looking wide-beam antenna was researched. The expression for the measured NRCS, taking into account the antenna beamwidth and the variation of the sea surface slope, was obtained, and the measuring algorithm of the sea surface wind speed was proposed. The obtained results can be used for creation an airborne radar system for operational measurement of the local wind situation over sea and for safe landing of a hydroplane on water.
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机译:万向节密封件-具有细长的球形密封表面,该表面可滑入较厚的外表面,以提供防尘密封等。AB DE4036616A两根轴(1、2)通过万向节连接,一根轴(2)装有一个球面联轴器(3)在第二轴的外球面内移动。第二根轴具有细长的球形密封表面(8),该表面在较厚的外表面内滑动。相互交叉的球形密封表面提供了有限的灰尘等进入的密封。密封唇(8a,9)密封了壳体的作用。优势-改进了对万向接头的保护,将砂砾损坏的风险降至最低。 AN 91194459 TI用于转速测量的脉冲环-倾斜的计数器部分沿环的外围压出,与传感器单元相互作用以确定速度和方向