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超短波通信从七十年代后半期开始在我省沿海海区推广使用,迄今已有1多年的历史。使用频段在超短波段低端——27MHZ到40MHZ范围调频制,射频输出功率1瓦到10瓦左右,频率间隔50KHZ(现已取消)和25KHZ,其数量达5千多台。超短波通信由于使用频率高,受天电及工业干扰很小,所以通信稳定。但是,超短波通信是直线通信,受地形、地物和地面大气状况变化的影响,通信距离一般都限制在视线距离以内或稍远一点,或用于近距离水面上船与船之间的通信,渔船在港内或锚地停泊期间,或进出港口时与岸上进行联络用。近几年,由于我省近、内海生产资源衰竭,渔业生产已逐渐向外海发展,直视通信的超短波无线
Since the latter half of the seventies, ultrashortwave communication has been used in coastal areas of our province for more than a year. The use of frequency band in the ultra-short wave band low-end - 27MHZ to 40MHZ range FM system, RF output power of 1 watt to 10 watts, the frequency interval of 50KHZ (now canceled) and 25KHZ, the number of more than 5,000 units. Ultra-shortwave communication due to the high frequency of use, by the small antenna and industrial interference, so the communication is stable. However, the ultrashort wave communication is a linear communication. Due to the change of terrain, ground objects and the atmospheric conditions on the ground, the communication distance is generally limited to the line of sight distance or a little further away, or used for communication between the vessel and the ship at the close range, Fishing vessels are to be used for liaison with shore while in port or anchorage, or when entering or leaving port. In recent years, as a result of the province near, inland sea resources depletion, fishery production has been gradually developing to the outside world, looking directly at the communication of ultra-shortwave wireless