A distributed phase measurement method of frequency-domain electromagnetic detection is proposed. The theoretical analysis of the previous literature shows that in electromagnetic detection applications, phase as an independent measurement parameter can reduce the diversity of solution, and it also has the advantage of greater steepness than the amplitude. Currently, there are few literature dealing with the phase in the practical application of audio electromagnetic detection, because it is difficult to obtain the phase from the separated devices. A synchronization recording system is designed based on the most widely used GPS and fiducial timestamp (FIDTS) technology. The phase errors caused by FIDTS, hardware circuit noise, and FFT spectrum leakage are analyzed. In addition, the synchronization data lost by GPS can be supplemented by interpolation. To prove the effectiveness of the method, a test platform was built in the laboratory. System test results show that the synchronization error between any two systems is less than 48 ns, and the phase error is less than 0.173° at 10 kHz. The experimental result of abnormal loop shows that the phase is more accurate than the amplitude.

中文翻译：

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频域电磁探测的分布式相位测量方法


提出了一种频域电磁检测的分布式相位测量方法。以往文献的理论分析表明，在电磁探测应用中，相位作为独立的测量参数可以减少解的多样性，并且还具有比幅度更大的陡度的优点。目前，很少有文献涉及音频电磁检测实际应用中的相位，因为很难从分离的设备中获取相位。同步记录系统是基于最广泛使用的GPS和基准时间戳（FIDTS）技术设计的。分析了FIDTS、硬件电路噪声和FFT频谱泄漏引起的相位误差。另外，GPS丢失的同步数据可以通过插值来补充。为了证明该方法的有效性，在实验室搭建了测试平台。系统测试结果表明，任意两个系统之间的同步误差小于48 ns，10 kHz时相位误差小于0.173°。异常环路的实验结果表明，相位比幅度更准确。