Beam scannable 4×4 patch array antenna using tunable metamaterial phase shifters

A beam scannable 4×4 patch array antenna using the tunable metamaterial (MTM) phase shifter has been designed at S-band. The phase shifter consists of four MTM unit cell composed of a series variable capacitor and a shunt tunable inductor. The inductor is realized by a variable capacitor and quarter wave impedance transformer. The phase shifting range of the phase shifter is 280° (from -87° to 193°) with the insertion loss of 0.9 dB. The 10 dB bandwidth and maximum gain of the antenna are about 94 MHz and 16 dBi, respectively. The beam scanning ranges in the E- and H-planes are 43° and 75°, respectively.