SICL fed Ka-band Dual Polarized Dipole Antenna Array for 5G Endfire Application

In this paper, a 1×4 dual polarized mod-ified dipole antenna array fed by Substrate Integrated Coaxial Line (SICL) is presented in Ka-band. The pro-posed array is achieved using two orthogonal radiating dipole antennas employing the standard ±45° slant technique. The elementary antenna is implemented by two 45° tilted modified dipole antennas printed orthogonal to each other on the top plate of substrate. The other dipole arm is implemented using the middle plate of SICL feeding network. The polarization of the antenna is controlled by exciting the antenna through either of the two feeding ports. A 1×4 stacked array of proposed antenna using L-bent SICL feeding network is utilized to obtain a gain of 7.6 dBi while maintaining good isolation. The proposed antenna resonates at 26 GHz exhibiting wide impedance bandwidth for the two polarization and co-pol to cross-pol ratio better than 23 dB. SICL helps in achieving a compact design by eliminating balun to feed the two arms of the dipole. Moreover, the feed network is compact and attains good isolation due to shielding. Another advantage of designing the antenna in SICL technology is the improvement in front-to-back ratio caused by the reflection of back radiations from the ground plates of SICL feeding network. This antenna finds its utility in n258-NR (New Radio) 5G spectrum endfire applications centered around 26 GHz.