Coding Artificial Magnetic Conductor Ground and Their Application to High-Gain, Wideband Radar Cross-Section Reduction of a 2x2 Antenna Array

A new technique is proposed for designing a low-scattering 2 x 2 antenna array using strategic coding metasurface ground for wideband bistatic and monostatic backscattered energy level reduction. Two various artificial magnetic conductor (AMC) units cells are organized like a chessboard to obtain an effective 180 degrees +/- 37 degrees reflection phase difference over a broadband frequency range. The low-backscattering microstrip antenna array is achieved based on the destructive interference theory and diffusion property of AMC unit cells. Simulations show that the proposed antenna array has a considerable backscattering field level reduction of 4.7-18 GHz for both the x- and y-polarization incident waves. It should also be noted that the maximum reduction of backscattered energy at a frequency of 7.2 GHz is -18 dB. The bistatic backscattering performance of the antenna is also given at different frequencies. Both a reference and a proposed prototype are fabricated, and the results are analyzed. Measurements of the fabricated prototype coincide well with simulations.