Bandwidth enhanced and sidelobes level reduced radial line slot array antenna at 28 ghz for 5G next generation mobile communication

Abstract

Radial Line Slot Array Antenna has simple structure and exhibit good radiation characteristics. It is low cost, easy to manufacture with high gain and it found application in services like Direct Broadcast Services and Wireless LAN. Its features make it attractive for millimeter wave mobile broadband applications like the fifth generation (5G) mobile communication system. Also, it can be designed for circular, linear or elliptical polarization. But achieving a reduced sidelobes level has not been an easy task in its design. This paper presents a simple technique to improve the impedance bandwidth and reduce the sidelobes level in linearly polarized Radial Line Slot Array Antenna at 28 GHz for 5G mobile communication system. In the design, high frequency laminate RT duroid 5880 and air gap were utilized with a modified dielectric coated 50 O SSMA connector as the coaxial to waveguide transition. The technique was experimented via simulation on Computer Simulation Technology Microwave Studio 2014 software. The simulation result gave a return loss of -18.98 dB at 28 GHz. Gain of 23.3 dB, 10 dB impedance bandwidth of 1.28 GHz, sidelobes levels of: -16.5 dB (Eplane); -17.5 dB (H- plane) and efficiency of 96 % were also realized.