Abstract
This communication reports the design of highly compact cavity-backed self-diplexing Y-shaped slot antenna for high-isolation employing quarter-mode substrate integrated waveguide (QMSIW). The proposed antenna is built by using QMSIW, Y-shaped slot and two 50 omega feed lines. Two unequal radiating apertures are developed by inserting an Y-shaped slot on the top side of the rectangular SIW for radiation at 3.9 and 4.9 GHz for long term evolution (LTE) and public safety band (PSB) applications, respectively. By keeping another band unaltered, the proposed antenna allows any frequency band to be tuned independently. The size of antenna is highly compact due to the use of QMSIW cavity. The isolation between two ports of the antenna is greater than 34 dB. The antenna achieves 5.43 and 5.85 dBi peak gains at 3.9 and 4.9 GHz, respectively. On both the frequency bands, the antenna efficiency is greater than 85%. The antenna has a front-to-back-ratio of more than 20.6 dB and a separation from co-to-cross polarization level of more than 21 dB. Through manufacture and measurement, the designed antenna is validated.