A phased array antenna employing reconfigurable defected microstrip structure (RDMS)

In this paper, a compact phase-shifting unit based on reconfigurable defected microstrip structure (RDMS) is used to provide controllable phase shift for a 1×4 phased array antenna. The RDMS is made by etching two slots on the microstrip line and loading with PIN diodes. By controlling the working states of the employed PIN diodes, the RDMS is able to provide phase shift. A 1×4 phased array antenna is built employing optimized RDMS. The tested results show that the antenna can work in the frequency band from 5.1-5.4 GHz, and switch its beam to -15°, 0°, and 15° in the H-plane with the average gain of 10 dBi. Compared to our previous work, significantly size reduction of 55% is achieved with similar performance.