【摘要】 研究UHF频段的无线电波在矩形、圆形和拱形隧道中的传播特性,推导了衰减常数的计算公式。在不同的隧道中,电磁波的衰减率有相似的计算公式,只是公式前面的系数不同,衰减常数随隧道截面尺寸的增大或工作频率的增加而减小。在工作频率f=500~1000MHz时,各种隧道中电磁波的衰减率很小,结合实际情况,采用900MHz作为井下移动通信的工作频率是比较理想的。其结果对铁路隧道、公路隧道等有限空间的无线通信具有参考价值。更多还原

【Abstract】 Propagation characteristic of UHF radio wave in rectangle ,circle and arched tunnels is studied in this paper and the computing equation for attenuation constant is deduced. In different tunnels the attenuation constant has the similar calculating expressions and it will decrease with the increasing of tunnel’s cross dimension or working frequency. The attenuation rate of electromagnetic wave in all tunnels is very low when the working frequency is about 500~100 0MHz. On the foundation of practical condition, it is perfect to choose 900MHz as the working frequency of mobile communications in mine well. The result is useful to the wireless communication in finite space of railway-tunnel, highway-tunnel.更多还原