Research On Signal Detection Method Of Underground Acoustic Wireless Telemetry System

With the continuous development of the petroleum industry and wireless transmission technology,more and more people have begun to study the use of wireless transmission methods in the field of oil and gas wells.Among them,the acquisition of downhole information is an important issue for research.The analysis and analysis can be used to evaluate the formation environment,which is of great significance to the exploration and development of oil and gas.The use of traditional wired transmission to obtain downhole information has many shortcomings that need to be resolved.Relatively speaking,wireless transmission can make up for these shortcomings.Among them,the use of sonic wireless transmission to obtain downhole information is Many people have studied the important method,simple operation and low cost,which has attracted much attention.This article analyzes and studies the properties of sound waves as they travel along the tubing string,the attenuation factors of transmission,and the effects of noise during the transmission process.We have a deep understanding of the frequency spectrum characteristics of the alternate stop bands of sound waves as they travel along the string.This characteristic was verified through experiments,which provided a reference for the following simulations and the selection of frequencies in the experiments.The COMSOL software was used to simulate the transmission of the acoustic waves along the oil pipe,which provided a reference basis for the wireless measurement of acoustic waves.The transmission amplitude,frequency,transmission / reception distance,and the presence or absence of couplings,these important factors have an impact on the transmission,and propose ideas and improvement suggestions for practical design and data processing,which are indispensable for sonic wireless telemetry research.One less step.Based on the theoretical analysis and simulation calculations,suitable hardware circuits and software systems were designed for the ground detection and processing of the sonic wireless telemetry system signals.With debugging,a platform was set up for testing in the laboratory.The piezoelectric acceleration sensor was successfully used In order to convert the acoustic wave signal to electric signal,because the acoustic wave is greatly attenuated and noisy during transmission,the amplifier and filter circuit are designed to amplify the acoustic wave signal submerged in the noise and filter out some interference.To achieve the acquisition and preservation of acoustic signals,it provides great convenience for practical work.At the same time,the host computer demodulation system is designed to realize the modulation and demodulation of the FSK signal in the software environment,which is a real-time solution in practice.Adjust the data for reference.The research results have strong practicality and can solve many problems in acoustic wireless telemetry.