Research On The Electromagnetic Wave Propagation Characteristics In Curved Rectangular Tunnel

With the development of the coal industry into the "13th Five-Year" period,in order to ensure the safety of coal production and the staff's life and property,establish a safety wireless communication system has become an urgent requirement of perfect.It is very important to study the propagation characteristics of electromagnetic wave in the tunnel.Coal mine tunnel is a limited space,the environment is complex,and many factors affect the propagation of electromagnetic wave.Due to the limitation of actual mine safety requirements,we cannot go deep into it.However,there are many similar space environments for mine tunnel,such as highway and railway tunnel.The study of the propagation characteristics of electromagnetic waves in the public(iron)road tunnel will also promote the development of the wireless communication technology in the mine tunnel.This paper is based on the wave mode propagation characteristic in rectangular tunnel and the analysis of curved tunnel corner ray path with ray tracing method,using the software to study the different antenna polarization,different frequency of electromagnetic wave propagation effects of theoretical analysis,modeling and simulation,found that the influence of antenna polarization on the propagation characteristics of electromagnetic waves in curved tunnel with the straight tunnel have great differences,and verified by experiment.In this paper,the influence of the position of antenna on the propagation characteristics of electromagnetic wave in a curved tunnel is further studied.Draw the Conclusion: when the tunnel width is greater than the high,horizontal polarization electromagnetic waves has greater influenced by transmitting frequency,low frequency,horizontal polarization is better than vertical polarization,frequency increases,the vertical polarization is better than horizontal polarization,when the transmitting frequency is greater than a certain value,the effect of polarization difference decreased.When the width changes with the position of the transmitting antenna,near the tunnel medial wall attenuation is the maximum,near the outer wall attenuation is the smallest,the middle position of low attenuation.when the antenna in the middle of different height,middle section is more suitable for the propagation of electromagnetic wave,cross antenna height is not far from the middle,middle section and similar propagation characteristics;attenuation increases with the increase of the distance.Is not conducive to the spread of.It is of guiding significance for the polarization mode of transmitting and receiving antenna,the selection of transmitting frequency and the position of installation for the actual curved rectangular tunnel.The innovation of this paper is mainly research on the propagation characteristics of electromagnetic waves in curved rectangular tunnel to distinguish empty and straight tunnel,more close to the actual tunnel environment,at the same time,the influence of environment parameters of electromagnetic wave propagation in the set range more widely,from a single frequency in different polarization mode changes to the same polarization mode with different transmitting frequency of the different antenna geographical location,the research more extensive.