城市地形对电波传播的影响及传播模型的修正

Effect of City Terrain on Propagation and Correction in Propagation Model

为研究移动通信中无线信道特性和电波传播规律,本文对距基站2.5km处8个不同的测量点接收的信号电平进行了实测与研究.结果表明:在2.5km测量出的接收电压电平值是正态分布,且电波传播表现出明显的慢衰落特征.过往车辆越多,建筑物密度越大,接收电压电平越低,反之亦然;用传播模型Hata和COST231-Hata拟合得到的地形校正因子集中在-1dB^-8 dB范围.该结论可为城市移动通信工程设计和无线网络规划提供理论依据.

To study the characteristic of wireless channels and regularity of electromagnetic wave propagation in this paper, the condition of received signal voltage level is measured and researched in 8 sites which are of same distance,2.5Km,away from the base station. The result shows： the received signal voltage level is normal distribution, as well as the electromagnetic wave propagation characteristic shows slow fading obviously. The more passing by cars and building density, the lower of received signal voltage level,and vice versa. Terrains correction factors calculated by the propagation model Hata and COST231-Hata range from -1dB to --8dB. This conclusion can provide theoretical foundation for city mobile communication design and wireless network plan.