基于差分脉码调制的随钻测量数据压缩编码算法

An algorithm for MWD data compression based on differential pulse code modulation

对随钻测井数据信息熵、概率分布和相关系数的分析表明,随钻测井数据具有分布集中、变化平缓和相关性强的规律。以此为根据提出了基于差分脉码调制(DPCM)算法的实时测井数据压缩编码方法。该方法通过降低随钻测井数据的相关冗余达到有效压缩随钻测井数据的目的,具有可灵活调整解码质量、算法复杂度为常数阶的优点。实际随钻测井数据的编码实验结果表明,在保证编码压缩后的随钻测井数据与原始随钻测井数据误差不超过5%的前提下,该方法能将实时传输的随钻测井数据量压缩为原始随钻测井数据量的一半以下,从而使随钻测量系统的传输效率提高到原来的两倍以上。

Analysis of the comentropy,probability distribution and correlation coefficient of measurement-while-drilling（MWD） data shows that the data has the regularity of concentrated distribution,gentle change and strong correlation.This paper proposes a real-time logging data compression approach which uses differential pulse code modulation（DPCM） to compress the logging data.The approach can compress the logging data effectively by reducing their redundancy,and achieve good decode quality and low algorithm complexity.Experiments on the real logging data show that the method can compress the real-time MWD data by half and increase the transmission efficiency of the MWD system by double times when the error is less than 5% between the compressed MWD data and the original MWD data.