| 2. | The millimeter has the largest frequency band and the highest velocity of communication , but it has the highest cost and technical defaults : multi - path effect , reflect and scatter caused by cloud , smoke , water - dropping , the buildings , the grounds and its shape , the interference caus ed by the thunder , the complexity of device , difficult maintenance , and so on . now the band of the leakage coaxial line is up to 3ghz , leakage coaxial line has some advantages : good adaptability to cloud , smoke , water - dropping , the buildings , the grounds and its shapes , good steady field , it has some technical defaults : lower resolution for location and measuring velocity , the more complex of its sending - receiving relay devices , weak anti - interference , the strict demand for the hole size in the line , the cleaner work environment and the higher cost 毫米波具有最大的带宽和最高的通信速率,但也有最高的成本要求和较难克服的技术问题,即传播的多径效应,降水、云雾、地形、地貌、建筑物等的反射散射,打雷时的严重干扰,设备复杂,维护困难等等;泄漏同轴电缆的带宽目前已做到3ghz ,具有对地形地貌建筑物的适应性强,场强稳定,但它的定位测速精度低,它的收发中继设备较复杂,抗干扰能力低,电缆上的开槽有着严格的尺寸要求,工作环境要求清洁,成本较高;传统无线感应技术具有结构简单,成本低廉,维护方便,定位精度较高的优点,但是,它没有抗干扰能力。 |