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已建成并测试了具有精确表面的7米偏置卡塞格伦天线。用一个地面信号源进行测量,并与19、28.5和99.5千兆赫的计算进行了比较。用一个复用损耗很低(～0.1分贝)的19/28.5千兆赫准光学馈源系统,当偏离主射束1度时就获得低旁瓣电平(≤-40分贝),而在整个主射束范围内达到了低交叉极化(≤-40分贝)。在99.5千兆赫进行主焦式增益测量时,发现测量的与计算的增益之间有(0.79±0.45)分贝的差值,这与预计的表面误差均方根值(～0.1毫米)是一致的。如果设备本身没有故障,那么,多波束工作就适于19和28.5千兆赫的COM STAR信标传播试验及毫米波射电天文观测。
A 7-meter offset Cassegrain antenna with a precise surface has been built and tested. The measurements were made with a ground source and compared to 19, 28.5 and 99.5 GHz calculations. With a 19 / 28.5 gigahertz optical feed system with low multiplex loss (~ 0.1 dB), a low sidelobe level (≤-40 dB) is achieved when deviating one degree from the main beam, whereas in the whole master Low cross-polarization (≤-40 dB) is achieved in the beam range. When the main focus gain was measured at 99.5 GHz, a (0.79 ± 0.45) decibel difference between measured and calculated gain was found, which was consistent with the expected root mean square error of surface error (-0.1 mm) . If the device itself is not faulty, then multibeam operation is suitable for 19 and 28.5 GHz COM STAR beacon propagation tests and millimeter-wave radio astronomy observations.