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从电视发射天线到接收天线的周围空间,电波传播往往受着很大的影响,这可以从接收电视图象上明显地看出来。同一台电视接收机放在不同的位置,图象质量会有很大差异,表明位置不同,场结构也不同。用改进电路特性的方法是不可能解决如画面上出现重影等问题的。因此,研究空间波在传播过程中的情况并制定出使重影消除或减少到最小程度的措施,是很有现实意义的。在城市中,高层建筑物不断涌现,如不采取措施,想接收高质量的电视图象是有一定困难的。大家知道,电视频道属于甚高频(VHF)和超高频(UHF)范围,
The propagation of radio waves from the transmitting antenna of the television to the space around the receiving antenna is often greatly affected, as can be clearly seen from the reception of the television image. The same TV receiver on a different location, the image quality will be very different, indicating that the location is different, the field structure is also different. It is impossible to solve such problems as ghosting on the screen with the method of improving the circuit characteristics. Therefore, it is of great practical significance to study the situation of space waves in the transmission process and to make measures to eliminate or minimize the ghosts. In cities, high-rise buildings continue to emerge. There is some difficulty in taking high-quality television pictures without taking measures. As we all know, TV channels belong to the VHF and UHF ranges,