Research And Implementation Of DSP Data Compression Algorithm For Cross-dipole Acoustic Logging

In the practical application of the cross-dipole acoustic instrument,there is a problem that the transmission bandwidth of the articulated instrument is not enough and the data transmission efficiency is low.This requires studying the compression method used to solve the problem of excessive amount of sound waves.The main task of the thesis is to design a data compression algorithm suitable for the underground DSP processing system based on the characteristics of cross-dipole acoustic logging tool.Compression algorithm after many years of development evolved a lot of types,its design and selection need to consider a variety of factors.The compression algorithm of acoustic logging data was studied,The algorithm was designed according to the requirements of the project and the actual use of the instrument.The algorithm was based on the principle of ADPCM coding,and the adaptive idea was used to quantify And the combination of predictive coding design codec flow,the need for 16 bit storage space of the acoustic signal amplitude data into only 4bit space difference data to store,to achieve a fixed ratio of 4:1.The algorithm was simulated with C language.The results show that the algorithm could meet the requirements of data compression in the downhole and can solve the engineering problems such as the mismatch of the transmission bandwidth caused by the other series of instruments.