Abstract:According to the channel characteristics of the periodic drill string, a one-dimensional low-frequency longitudinal wave transmission model is established based on the finite-difference algorithm. By using a single accelerometer as an acoustic receiver, the effects of the positions of the receiver on acoustic signal transmission are analyzed using simulations in time and frequency domains. Then, considering the channel capacity with regard to the influences of multi-echoes on acoustic communication signal detections, a dual acoustic receivers-based echo noise suppression method is designed by introducing unit impulse exciting responses of up-going and down-going channels. The cepstrum analysis method is used to extract the echo information from the received acoustic signals. In addition, the characteristics of the channel response on single and dual receivers are analyzed. The numerical simulation results illustrate that the proposed dual-receiver method can effectively suppress underground echo noise and improve the signal-to-noise ratio (SNR), which contributes to better channel receiving performance.