天线技能的提高-三线式短波基站天线(国外英文资料).docVIP

天线技术的进步-三线式短波基站天线(国外英文资料) Advancements in antenna technology - three-wire short-wave base station antenna In recent years, many large users of the military and local areas and many vendors of wireless equipment have learned more about the three-wire antenna and have been widely used. The upgrade target for the three-wire antenna is a popular cage antenna and a regular bipolar broadband antenna. Cage antenna is a kind of performance is very good directional antennas, communication distance is farther, but heavier, erect inconvenience, poor ability to resist wind, use frequency is relatively narrow, the price is more expensive. Common bipolar antennas because the price is very cheap, easy erection, adopted by many users at the grass-roots level, but the efficiency is low, the generally high frequencies in standing wave ratio, effective frequency band is narrow, erect unstable state (the wind), communication effectiveness is difficult to guarantee. In addition, there is a common technical limitation of the two antennas, which is that only directional communication can be carried out, with no guarantee of communication and close range of communication. The three-wire antenna retains the advantages of both antennas: it is similar to a cage antenna on energy efficiency. In terms of size, weight and ease of erection it is about the same as an ordinary bipolar broadband antenna. More important is that it fully make up for the deficiencies of these two kinds of antenna: (1) set up steady state, can always stay level state, will not sway in the wind, together with lighter weight, greatly improve the wind resistance, stability of communication is better; , which works in the short wave full spectrum; is not only for directional communication, but also for all non-blind areas. The cost of the is higher than the standard double pole broadband antenna, but is significantly lower than the cage antenna. To sum up, the performance price of a three-wire antenna is much higher tha