Development of a V-band Rotman Lens using thin-film substrate with a flip-chip interconnection

This paper proposed the symmetry Rotman Lens which is enabled beam steering at mm-wave. The Lens which has four beam ports and eight array ports has four dummy ports at beam curve in order to reduce multi reflection from the inside of the lens, and the side wall of the lens was minimized. Also the array curve is designed without a dummy port in order to reduce insertion loss. The lens has been employed as a feeder of eight linear array antennas with spaced 0.5lambda (2.5 mm), showing beam steering angle of -20deg, -6deg, +4deg, +18deg and HPBW of 11deg~13.5deg. The beam steering antenna module is mounted a antipodal fin line transition, SP4T switch, and PA on metal jig, showing gain of 17.3 dB~18 dB and SLL of 7.3 dBc.