A portable electric field detector with precise time base for transient electromagnetic radiation source location

An electric field ( E-field) detector with the features of precise time base, full-waveform storage, and wireless data transmission has been developed, which can be used in combination with location algorithm for accurate location of the transient electromagnetic radiation source over a large-scale area. The maximum sampling rate is 2 GS/s, and the memory depth is up to 128 kB and can be adjustable. The measurement range can be adjusted from hundreds of V/m to tens of kV/m with different lengths of antennas. With the help of the global positioning system (GPS), both the clock and the position of the detector can be synchronized. In particular, the time instant triggered by the signal could be recorded with the time resolution of tens of nanoseconds. Therefore, the precise time base alignment among multiple detectors could be achieved, which is crucial for location accuracy. Then, all data including the signal, the position, and the time instant could be sent to a remote server by the fourth-generation mobile (4G) communication technology. The calibration results show that the bandwidth of the detector could vary from 10 kHz to 500 MHz, while the time base alignment error between any two detectors is less than 50 ns. An experiment was performed by means of electromagnetic time reversal (EMTR) method to prove the applicability of the detector and its location accuracy. The detector could be used to measure and locate lightning, partial discharge, or fault.