基于FPGA的地震波六分量同步采集系统

Seismic Wave Six-component Synchronous Acquisition System Based on FPGA

传统多波三分量地震勘探仪器缺失地震波旋转矢量信息,导致后期数据处理和数据解释精度差,进而限制地层反演的精度和速度。针对该问题,本文阐述了一种地震波位移矢量和旋转矢量的六分量同步采集系统。该系统以FPGA为采集平台,硬件上设计可动态配置前端信号调理电路,保证了系统采样精度和动态范围。ADC控制模块采用逻辑状态机实现6路并行采集,数据暂存通过2个异步FIFO和1块SDRAM实现数据位宽匹配问题和跨时钟问题。实验结果表明能够同步采集到位移矢量和旋转矢量信息,并且采集精度为μV级。

Traditional multi-wave three-component seismic prospecting instrument lack the rotation vector information of seismic wave,resulting in poor accuracy of data processing and data interpretation in the later stage,thereby limiting the accuracy and speed of formation inversion.Aiming at this problem,a six-component synchronous acquisition system of displacement and rotation vectors of seismic waves was described in this paper.The system took the FPGA as the acquisition platform and designed the front-end signal conditioning circuit which can be dynamically configured to ensure the sampling accuracy and dynamic range of the system.The ADC control module implemented 6 parallel acquisitions using a logic state machine.Data temporary storage implements data bit width matching problems and cross-clock problems through two asynchronous FIFO and one SDRAM.The experimental results show that the displacement vector and rotation vector information can be acquired synchronously,and the acquisition accuracy is in the microvolt level.