Antenna Array in UWB Security Application

Abstract

The aim of this thesis is to design and implement a microstrip patch Vivaldi (UWB) array antenna with a single feed Wilkinson power divider network at an operating frequency of 5.5 GHz printed on a dielectric substrate ASTRA ® MT77 material which can reduce the security issues at each layer of UWB technology. The initial work of this thesis is to design and analyse the 2×1 and 4×1 Wilkinson power divider network which improved the isolation and matching of the ports. Later, on the designed array feeder network two and four rectangular radiating patches have been mounted in a linear configuration to achieve the required radiation properties. Finally with the help of simulated rectangular patch array antenna along its dimensions the structure has been improved to develop and construct the Vivaldi array antenna to attain the maximum bandwidth and gain in an optimum UWB bandwidth. The antenna array is designed using standard equations and simulated by professional antenna development software called High frequency structural Simulator (HFSS). Among many antenna simulators, HFSS is selected as it allowed the inclusion of anisotropic ferrite material in the simulation process. The prototype array antenna is printed on a chosen dielectric substrate using the PCB plotter. Finally, the simulated reflection response and radiation characteristics of the designed Vivaldi array antenna are validated using experimental results obtained from the Network analyser and the Antenna Transmission & Measurement System respectively. It has been observed that the experimental array antenna exhibited very close radiation response to that of design objective.