A fundamental study on estimation method of 10 m test-range electric field strengeth by near-field measurment

In this paper, we have fundamentally studied the estimation of 10 m test-range electric field strength height pattern by means of measuring the tangential electromagnetic fields on the cubic surface surrounding Bi-conical and Log-periodic antennas placed above the ground plane by using the differential electric and magnetic probe. The analysis frequency range is from 30 MHz to 1GHz, and the polarization is both horizontal and vertical. The 10 m test-range electric field strength is calculated according to Field Equivalent Principle through replacing the electromagnetic fields with the equivalent surface currents. And also, the ground plane is hypothesized the infinite conductive plane, and the image receiving point is formed against the real receiving point above the ground plane. The 10 m test-range electric field strength is calculated by adding the each estimated electric field both the real and image receiving point. As the results, the estimation of 10 m test-rang electric field strength height patterns at each polarization are in agreement with NEC2-calculation. There are within ±1 dB, except null points. The estimation results with the condition of ground plane demonstrated the effectiveness of the proposed method.