A new uniformity-enhanced double ridged horn antenna for radiated susceptibility test from 1 GHz to 18 GHz

In this paper, a new double ridged horn antenna design is proposed. The antenna is especially suitable for the radiated susceptibility test from 1 GHz to 18 GHz as required by the regulation IEC/EN 61000-4-3. A tapering shape of the flared section and a new coupling coaxial feed structure are introduced and optimized to improve the main-beam direction and the half power beam width (HPBW) of the radiation pattern. Moreover, the impedance matching bandwidth is increased. The well designed antenna was implemented and measured inside a standard 3-m semi-anechoic chamber to show the performance achievement. By testing the field uniformity, the proposed horn antenna indeed can radiate the uniform wave with the field strength 5.4 V/m, within 0 dB to 6 dB differences to the nominal value at more than 75% of the measured grid points, from 1 GHz to 18 GHz.