HF Magnetic Field Standard

A magnetic field standard system is developed using a small loop antenna based on the standard field concept for frequencies from 0.1 to 30 MHz with an accuracy of 0.12 dB. A wide-band loop antenna is designed as the standard antenna to generate the standard field which is determined from the incident power to the standard antenna and its antenna factor measured by the three-antenna method. An incident power monitor is designed to measure accurately the incident power to the standard antenna. A two-antenna method is devised for precise calibration of loop antennas for practical use.