Development of 10 MHz-1000 MHz small leadless electric field probe

Rev Sci Instrum. 2021 Jan 1;92(1):014703. doi: 10.1063/5.0030004.

Abstract

In order to realize the miniaturization and leadless function of the electric field probe working from 10 MHz to 1000 MHz, a small stand-alone probe based on the dipole and Schottky detector diode is developed in this paper. First, a 20 mm dipole printed on the circuit board is adopted as the receiving antenna, and the Schottky detector diode is connected across the two arms of the dipole. Then, the signal output by the detector diode is amplified by a chopper amplifier circuit, which also isolates the alternating component. Finally, a microprogrammed control unit is set inside the metal shield to realize data acquisition and storage. The size of the probe developed is not exceeding 20 × 20 × 30 mm3, and the characteristics of the probe are temperature dependent. The field strength from 1.4 V/m to 1627 V/m can be measured within 10 MHz-1000 MHz, achieving a dynamic range over 61 dB at 21 °C. It has the advantages of small size, large dynamic range, and integrated data collection and storage.