The Research Of Key Technology On Channel Detection For Through-The-Earth Communication Based On Elastic Waves

The research level for channel detection technology and the comparison of several common detection methods were introduced in this paper. According to the development needs of mine communication, this paper gave a further discussion on the propagation rule of elastic wave in the stratum medium by using theory of seismic exploration. Combining with the stratum medium structure, the paper discussed the influence of wave parameters on the elastic wave propagation in earth, emphatically analyzed transmission characteristics and wave equation of elastic wave in isotropic and uneven medium.Exclusive characteristics of the earth channel were analyzed, including invariable parameter characteristics and low-pass filter function of the earth channel. The earth has frequency selectivity for elastic wave attenuation. The influence of piezoelectric effect, waveguide effect and multi-path effect was discussed deeply. Reflection, refraction and transmission of elastic wave were analyzed with the attenuation characteristics in earth.With the analysis of the earth channel characteristics, channel detection scheme was designed, detection system was built, the best frequency and channel parameters of the elastic wave was found by taking Chirp-CHEC detection methods. The earth channel was divided into sub-channels, each sub-channel BER was found by error count detection method, and detection results were filled into LQA forms. The extraction methods and standards of channel parameters were discussed. Absorptive attenuation, multi-path delay and best frequency were analyzed. Finally, frequency selective simulation of channel detection system was provided. Results showed the system worked normally, and realized the function of choosing frequency.The research achievements can provide parameters support for through-the-earth communication system of elastic wave, and have reference value to mine communication, tunnel communication, military underground tunnel communication, geological prospecting and so on.