Design of Vivaldi Antenna Array with a Back Reflector for Low Side Lobe Level and High Gain

Abstract

This paper presents a proposal of new 10×1 microstrip Vivaldi antenna array with a low side lobe level and high gain. To obtain low side lobe level, tapering amplitude technique has been applied. The amplitude distribution has been obtained by using the Bat algorithm and has been implemented through a series feeding network. 10 Vivaldi antenna elements and the feeding network have been constructed co-planar on Roger RO4003C with the size of 140 × 450 × 1.524 mm3. To improve the performance of the array, a back reflector has been proposed and investigated. The simulation result shows that the side lobe level has been suppressed up to 28 dB from the main lobe at the frequency of 3.5 GHz while the maximum gain is around 16.5 dBi; Both simulated and measured reflection coefficients indicate that the array has an operating frequency range of 3.44 – 3.58 GHz (bandwidth 140 MHz) with S1,1 =-10 dB. The proposed array can be a good candidate for fixed wireless access systems, 5G wireless systems in the C band.