A frequency-independent phase shifter and low-profile phased array module

We have demonstrated a robust and stable frequency-independent phase-shifting mechanism using the phase pattern of the spiral antenna, which has been investigated without success with enormous efforts and expense during the past two to three decades. The integration of this phase switching into the low-profile wideband spiral-mode microstrip (SMM) antenna readily yields a low-profile phased array module with bandwidth over 10:1. This array module also has potentially lower insertion loss, and higher power-handling capability, than the PIN-diode phase shifters. In addition, this integrated antenna/phase-shifter appears readily applicable to PSK (phase shift keying), including BPSK (binary PSK), QPSK (quadrature PSK), and MPSK (M-ary PSK, N bits) in digital communication systems.