Phased Array Antenna for Bi-Static Simultaneous Transmit and Receive (STAR) system

Bi-static simultaneous transmit and receive shared phased array aperture with wide-angle beam steering is discussed. Antenna system works over a narrow frequency range in K-band and has 10×10 circularly polarized stacked-patch antenna elements distributed in two 10×5 apertures for transmit and receive. Wide-angle scan through θ = 60
^°
elevation angles with axial ratio <; 6 dB is achieved by combining parasitic patch, aperture coupled feed, and corners' chamfering. Different approaches for enhancing isolation between the two apertures are considered and some results are shown herein.