Design And Implementation Of Digital Filter Bank For Seismic Exploration System

A digital filter bank used in seismic exploration system is investigated in this thesis.The structure and parameters of the filter bank is optimized according to the seismicapplication. It consists of three CIC (Cascaded Integrator Comb) decimation filter, onecompensation filter, and one FIR (Finite Impulse Response) decimation filter. Each filtersection is first simulated in MATLAB, then verified by Modelsim and implemented inAltera FPGA (Field Programming Gate Array) chip at last.The CIC decimation filters are used for sample rate conversion. This is achieved byextracting baseband signals from narrow-band sources using decimation. The keyadvantage of CIC filters is that they use only adders and registers, and do not usemultipliers to implement in hardware for handling large rate changes. The Compensationfilter is used to compensate the pass-band droop of the CIC filters. The FIR filter has alinear phase and inherent stability. It is used as the last stage of the filter bank tointensively suppress the unwanted signals.This thesis contain mainly4chapters:Chapter1. Introducing the principle and background of seismic exploration systemand its application requirement for the digital filter bank.Chapter2. The design and simulation of multi-stage digital filter bank throughMATLAB.Chapter3. The simulation and analysis of this design in the Quartus II and Modelsimplatform, comparing the results with those in MATLAB.Chapter4. A summary of the results and the further work and expectations for futurestudy.Highlight work: the principle and implementation of digital filter, including softwareand hardware functions to achieve.The difficulties: the digital filter anti-aliasing extraction, spill control, andimprovement of filtering performance.The results show that: multi-filter structure of the digital filter band and theparameters fully meet the design specifications.