A Wideband Dual-Polarized Dual-Mode Antenna With Simple Differential Feeding

A wideband differentially fed dual-polarized dual-mode antenna is presented in this letter. Four slots are placed a square shape to construct the slot loop antenna, and the outer ground of the slot loop is bended to achieve a compact size. A simple out-of-phase power splitter with a wide bandwidth and accurate 180 degrees phase difference is integrated with the radiator to feed the slot loop. The 1 and 2 lambda modes of the slot loop antenna are excited with the differential feeding for a wide impedance bandwidth (IMBW). By loading the distributed inductors at the ends of each slot, a radiator size of 106 x 106 mm(2) is obtained to cover LTE700/GSM850/GSM900 bands. Measured results show that the antenna has the IMBWs of 0.63-1.09 GHz (0.46 GHz, 53.5%) and 0.63-1.08 GHz (0.45 GHz, 52.6%) for the two input ports, isolation of more than 31.5 dB, and stable gain of around 7.15 +/- 0.35 dBi for Port 1.