随钻测量仪器中基于窗函数的FIR实时滤波器的设计

数字滤波器与传统的模拟滤波器相比,具有精度高、稳定性好和操作灵活等优点.为适应油气勘探开发向精细化解释评价方面发展,数字滤波器取代传统模拟滤波器已成为随钻测量仪器发展的趋势.从这一角度出发,探讨了基于窗函数的FIR数字滤波器的设计方法以及选取窗函数应该考虑的因素,并结合油气勘探随钻测量的特点,提出了将数字滤波技术用于无线随钻测量仪器,实现实时滤波的软件设计思路.实验室仿真和现场试用结果表明,依此设计的滤波器各项技术指标完全符合钻井现场的使用要求,具有实用价值.

FIR real-time filter design based on the window function of MWD unit

Contrasting with the traditional analog filter, the digital filter has the advantages of high accuracy, good stability, flexible operation etc., in order to adapt oil-gas exploration & development developing towards refinement interpretation and evaluation, the replacement of the traditional analog filter with the digital filter has become a MWD unit developing trend. Seen from this point, the paper discussed FIR digital filter designing method based on the window function and provided the factors which should be considered during selecting window functions. On the basis of it and combining with MWD features of oil-gas exploration, the paper put forward design procedures for the digital filtering technique to be used into wireless MWD unit and to realize real-time filtering. Laboratory modeling and field test results indicated that each FIR digital filter technical criterion can fully meet the operating requirements of on-site drilling and has really effectiveness.