Research On De - Noising Algorithm And Decoding Of Slurry Signal

Oil has become the indispensable necessities in People’s Daily life, is one of the main energy in the world. Now as the growth of the demand for oil and each big oilfield evaporating, makes difficult exploitation of oil exploration and development activities have had to face more complicated oilfield, in order to reduce Drilling difficulty and improve the efficiency of mining, MWD (Measurement While Drilling) technique is applied to large-scale oil exploration and development.MWD technology was conducted in drilling operation in real-time measurement and transmission of downhole information technology, do not need to interrupt bit work under the condition of underground detector to detect the various parameters of the information, and to transmit the information in a timely manner to the ground, ground signal processing system based on signal processing and identification of decoding the downhole measurement information is accurate, intuitive display and realize the real-time monitoring of downhole conditions in the MWD, ensuring the safety of drilling operation can be effectively, and can hit the target stratum in the process of guiding drilling.This article main research content to eliminate while drilling mud of mud pulse signal measurement noise and mud pulse signal decoding scheme is put forward.Because the mud pulse signal transmitted from underground to ground will be affected by the mud itself and in the process of downhole mechanical vibration and noise interference, and because the signal transmitted from underground to inoue distance is longer, the signal attenuation is serious, ground collected in mud pulse signal contains a lot of noise, they may even covered the original mud pulse signal, therefore how to interference from the frequency distribution of a wide range of noise in the background to detect the useful signal and decoding downhole information parameter has been a key problem of mud pulse transmission technology.In this paper, according to the characteristics of the noise interference, FIR filter algorithm and adaptive filtering algorithm and wavelet transform algorithm to deal with the noise of the mud pulse signal, obtain the useful signal, and Manchester coding and pulse interval coding of mud pulse signal according to the encoding corresponding decoding scheme, put forward finally in the Matlab platform of mud pulse in MWD system signal processing simulation experiment, make a workable solution.