A Low Profile Single Layer X-band Reflectarray Antenna Using a Novel Unit Cell

In this paper, a broadband microstrip reflect array antenna is designed for X-band Applications using a novel single layer (without air layer) unit cell. The unit cell consists of a quasi-log-periodic patch and two microstrip rings connected to variable length stubs. A phase variation range of 640 degrees was achieved for the optimized unite cell. Using this unit cell, a reflectarray with 145 unit cells was designed and simulated using CST software. Simulation results show a maximum gain of 22.7 dB and 3-dB gain bandwidth of 24.3% in the frequency range of 8.3-10.6 GHz. Maximum aperture efficiency of the antenna is 34%.