Channel Model of Sensor Signal Transmission in the Sewer

This paper is to resolve the problem on the credible transmission of detection signal in the sewer, in accordance with the transmission rule of signal in confined areas, the electromagnetic wave propagation in the sewer space is divided into the two different regions which are called near field and far field and giving the wave model equation of the electromagnetic wave propagation in the sewer. Theoretical analysis and experimental results show that the bigger conductivity, magnetic permeability, and dielectric constant in the sewer are, the smaller attenuation rate is, the higher frequency is, the smaller attenuation of electromagnetic wave in the sewer is, the bigger radius of the sewer is, more beneficial the electromagnetic waves transmit.