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自从人类成功发射第一颗人造地球卫星以来,人类便开始进入了太空时代,现在地球上空飘浮着上千颗卫星,广泛用于通信及广播电视的传送,收看数百套的卫星电视节目已不再是什么难事。以前的卫星电视主要为C波段,必须使用直径2.4-4.5米的抛物面天线才能接收到电视信号,而现在的卫星电视主要采用的是Ku波段,接收Ku波段的天线直径仅为C波段的三分之一,面积大大减小,而能容纳的节目比以前更多。接收Ku波段的天线安装十分方便,以前的抛物面天线必须安装在精确的位
Since mankind successfully launched its first man-made earth satellite, mankind has begun to enter the space age. Now thousands of satellites are floating above the earth and are widely used in communications and radio and television transmission. Hundreds of satellite television programs are no longer viewed What is more difficult. The previous satellite TV mainly C band, you must use a 2.4-4.5 m diameter parabolic antenna to receive television signals, and now the main use of satellite TV is Ku band, receiving Ku band antenna diameter is only C-band third One, the area is greatly reduced, and can accommodate more programs than ever before. Ku-band reception of the antenna is very easy to install, the previous parabolic antenna must be installed in the precise bit