可控震源中扫描信号的研究与设计

Research and Design of Vibrator Sweep

可控震源中的扫描信号发生器位于整个系统的最前端,其性能指标直接影响着由源致干扰引起的谐波畸变,对地震资料质量和分辨率产生较大影响,因此如何提高它的幅值和频率精度成为设计可控震源的一个很重要的课题。本文在DDS(直接数字频率合成器)原理的基础上提出软件DDS的方案,分时利用DSP(数字信号处理器)及数模转换器,模拟DDS芯片进行频率合成,同时对幅值进行精确控制。在此基础上对可控震源中的扫描信号进行研究与设计,并使频率、幅值等关键指标得到较大提升。

Vibrator sweep is the forefront of vibroseis,the harmonic distortion caused by the interference from the signal source was effected directly by the performance,which have great impact on the quality and precision of the seismic date,so it is a very important topic to increase the precision of amplitude and frequency.This paper bring forward a way of Soft Direct Digital Synthesizer on basis of Direct Digital Synthesizer,time-sharing from the DSP and DA convertor,simulate DDS for Frequency Synthesizer,and make a precise control of amplitude.On the basis of the above-mentioned conducted a study and design for the vibrator sweep of vibroseis,amplitude and frequency of performance is improved greatly.