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目前使用的电视天线,如室内外的鞭状、双鞭状、半波、定向单元、双环形、蝶形、抛面形、弧形、平面形、螺旋形、鱼刺形、十字形等天线都是固定式天线。不可能自动调整天线的接收方位。雷达式全频道室内天线,虽然采用相控阵中的“传输线抽头结构法”移相技术,但只能改变天线接收面方向的±60°,要接收多个方向的电视信号,还必须转动天线的方位。因此,人们希望对处于不同方向的电视信号均能获得最佳接收效果。满足这种要求的电视接收方法有两种。一是架设多付天线分别接收不同方位角的电视节日,这种方法安装复杂,而且在变换频道时要插换相应的天线,使用
TV antennas currently used are indoor and outdoor whip, double whip, half wave, directional unit, double loop, butterfly, parabolic, arc, plane, spiral, fishbone, Is a fixed antenna. It is impossible to automatically adjust the receiving orientation of the antenna. Radar all-channel indoor antenna, although phased array “transmission line tap structure method” phase-shifting technology, but only change the antenna receiving surface direction of ± 60 °, to receive multiple directions of the television signal, you must also turn the antenna Position. Therefore, people want to receive the best reception for television signals in different directions. There are two ways to receive television to meet this demand. One is to set up multiple antennas to receive different azimuth television festival, this method is complex to install, but also change the channel to be replaced when the corresponding antenna, use