【摘 要】
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In order to improve the resolution of seismic acquisition, a new seismic acquisition system based on tangential laser Doppler effect with an optimized differential optical configuration is proposed. The relative movement of the inertia object and the immo
【机 构】
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StateKeyLabofPrecisionMeasuringTechnologyandInstruments,TianjinUniversity,Tianjin300072StateBureauof
【出 处】
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ChineseOpticsLetters
论文部分内容阅读
In order to improve the resolution of seismic acquisition, a new seismic acquisition system based on tangential laser Doppler effect with an optimized differential optical configuration is proposed. The relative movement of the inertia object and the immobile frame is measured by laser Doppler effect, which can avoid the electromagnetic and thermometric interference, and the adoption of frequency-modulated (FM) transmission can improve the ability of anti-jamming. The frequency bandwidth is properly determined by analyzing the frequency of the Doppler signal. The velocity, displacement, acceleration, and frequency to be measured can be real-time acquired by frequency/velocity (F/V) converting the FM Doppler signal. A 100-dB dynamic range and the linear frequency range of 1.0 to 1000 Hz are realized.
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