【摘要】：對以階梯波作為參考信號的正交鎖定放大的探測精度進行了建模分析,基于硬件簡單原則給出了以階梯波作為參考信號的正交鎖定放大信號檢測方法的實現(xiàn)策略。綜合考慮參考波形的失真度與采樣率之間的關系,對比分析了基于面積等效法和特定諧波消去法的階梯波合成方法。根據階梯波參考信號對采集電路相位精度的要求及待檢測信號的周期性,提出了匹配采樣技術。實測結果表明:采用現(xiàn)場可編程門陣列(Field programmable gate array,FPGA)實現(xiàn)所提出的正交鎖定放大,方法簡單、硬件要求低、可用于識別不同異常體。改進后方法的誤差為0.7%~7%,與以方波為參考信號的正交鎖定放大相比,提高了探測精度。
[Abstract]:The detection accuracy of orthogonal locking amplification with ladder wave as reference signal is modeled and analyzed. Based on the principle of hardware simplicity, the implementation strategy of orthogonal locking amplification signal detection method with ladder wave as reference signal is given. Considering the relationship between distortion and sampling rate of reference waveform, the stepped wave synthesis method based on area equivalent method and specific harmonic elimination method is compared and analyzed. According to the requirement of the step wave reference signal for the phase accuracy of the acquisition circuit and the periodicity of the signal to be detected, a matching sampling technique is proposed. The measured results show that the proposed orthogonal locking amplification is realized by using field programmable gate array (Field programmable gate array,FPGA). The method is simple and the hardware requirements are low, and it can be used to identify different abnormal bodies. The error of the improved method is 0.7% 鈮，

本文編號：2524509