钻柱声传输的OFDM调制方法实现

摘要

为提高油气开采过程中随钻测井(LWD)数据传输速率,针对钻柱声传输技术中因周期性边界引起的色散和多重回波问题,从数据通信的角度出发,将正交频分复用(OFDM)多载波调制技术引入声传输系统,并以钻杆为信道,采用PC机结合FPGA模块和数据采集卡的形式,搭建了数据传输实验平台.数据传输实验结果表明,基于OFDM调制方式的短节钻杆声传输方案可实现160 bit/s的传输速率,该方案同时可为后续的钻柱声传输设计与实验提供方法指导.%In order to improve the data transfer rate of logging while drilling(LWD) , an acoustic transmission scheme based on orthogonal frequency division multiplexing (OFDM) multi-carrier modulation was proposed, at the angle of data communication, with considering the time dispersions and multiple echoes because of the periodic channel boundaries. The platform of acoustic transmission along the drill pipe was designed and built under the PC processing with interface of an FPGA breadboard and a data acquisition card. Experimental results show that the acoustic transmission scheme along the short drill pipe based on OFDM modulation technology has a reliable transmission of 160 bit/s transfer rate. Moreover, it provides a reasonable guidance for follow-up design and experiment research of acoustic transmission.