Out-of-Band RCS Reduction of HF/VHF Whip Antenna Using Curved AMC Structures

The whip antennas used for HF/VHF band communication on the vehicles or ships are generally larger in length and diameter. It would be of great significance if it could be easily hidden from microwave detection radar searches. Aiming at the lower RCS of whip antenna in X-band and maintaining the original impedance and radiation characteristics under high-power input, we propose a whip antenna integrating a novel curved artificial magnetic conductor (AMC) to achieve the RCS reduction in X-band. The backscattering of the cylinder can be dispersed by using the 180° phase difference cancellation principle of different AMC structures, and the mechanism is demonstrated by simulation and experiment. The measurements are in good agreement with the simulations, and the measurement results indicate that in the band of 8–12 GHz, the backward RCS is reduced by an average of 11.2 dBsm in VV polarization and by 10.2 dBsm in HH polarization. Moreover, the proposed whip antenna can be applied to high-power HF/VHF transmitting systems, and the withstand voltage can reach 15 kV (continuous output above 10 kW). This method has important theoretical significance and practical values for the whip antenna in practical engineering applications.