基于DSP的井下仪器幅值提取技术研究应用

The research and application of amplitude extraction technology of downhole tools based on DSP

研究幅值提取理论和井下测井仪器幅值提取需求,聚焦测井仪器最为关注的测速和精度,对井下仪器数字处理芯片DSP进行幅值提取编程,并烧写程序进行不同幅值提取技术运算速度和计算精度测试对比,给出数字相敏检波和FFT幅值提取算法在DSP中的运行速度和精度测试结果,结果显示在DSP中数字相敏检波运行速度比FFT处理速度快5~9倍,幅值提取精度也高于FFT,继续分析FFT幅值提取技术在井下测井仪器混频信号中的应用优势,展望了井下仪器幅值提取技术在可编程器件DSP和FPGA中的发展趋势和影响因素。文章从幅值提取技术和仪器需求出发,为后续测井仪器研发提供幅值提取技术选取参考,也为继续优化井下仪器幅值提取技术提供了数据支撑。

It studies the theory of amplitude extraction and the demand of amplitude extraction of downhole logging tools,focuses on the most concerned speed and accuracy of logging tools,programs the amplitude extraction of digital processing chip DSP of downhole tools,and writes programs to compare the operation speed and calculation accuracy of different amplitude extraction technologies,and gives the operation speed and accuracy of digital phase sensitive detection and FFT amplitude extraction algorithm in DSP.The test results show that the operation speed of digital phase sensitive detector in DSP is 5~9times faster than that of FFT,and the accuracy of amplitude extraction is also higher than that of FFT.The application advantages of FFT amplitude extraction technology in mixing signals of downhole logging tools are analyzed.The development trend and influencing factors of amplitude extraction technology of downhole tools in programmable devices DSP and FPGA are prospected.Based on the amplitude extraction technology and instrument requirements,this paper provides a reference for the selection of amplitude extraction technology for the follow-up research and development of logging instruments,and also provides data support for the continuous optimization of the amplitude extraction technology of downhole instruments.