A Low-Profile Binary Array Antenna for Integrated Beam Control and RCS Reduction

Integrated beam control and RCS reduction are becoming increasingly important for modern radar and stealth applications. This work presents a binary array antenna for simultaneously and digitally realizing beam control and RCS reduction. Specifically, the element antenna is a patch antenna with U-shaped slot. By reversing the patch, the radiation phase of co-polarized wave can be modulated in binary form. The reflection phase of cross-polarized wave is binarily modulated by loading or unloading a grounded metal post to the element antenna in cross-polarization direction. By designing binary codes of the array antenna in both co-polarization and cross-polarization directions, beam control and RCS reduction can be realized independently. A binary array antenna with 108 (8
×
16) element antenna is designed and fabricated. Transmission-line unequal-power divider is used to feed the array antenna. Both simulations and measurements have verified the presented digital mechanism for integrating beam control and RCS reduction.