26GHz无线LMDS系统中反射波对接收功率的影响

The Reflection Wave Affection of Received Power for LMDS System in 26GHz Band

一般在考虑LMDS系统的电波传播时,常忽略反射波的影响。但在城市复杂环境传播时,由于金属玻璃幕墙、江河湖泊、光滑地面或墙面等可能形成较大的反射波,使接收信号功率产生较大变化,在我们建立的38GHz无线LMDS试验网中就发现了反射波的影响。本文采用双射线模型计算了这种影响,与实测值基本相符,结果表明在武胜长信局中心站和研究所远端之间较宽的黄浦江面存在反射波,对系统接收功率产生相当影响。因此在进行LMDS系统设计时要考虑传播路径上可能的反射波影响。

The reflection wave affection usually can be neglected when considering the LMDS system propagation. But the received power can vary largely in the complex city environment such as metal glass wall, river or lake and plane wet surface. The affection of the reflection wave is detected in the try system. The double line model is used to calculated the affection and the calculated result is in good coincidence with the measured value. The result shows that the reflection wave of the Huanpu river between the two sites affects the system received power. The reflection wave affection through the propagation path need to be considered when designing the LMDS system.