Dual-segment corporate feed four elements array antenna for broadband application

A dual-segment four elements corporate feed array antenna operates at the center frequency of 5.55 GHz is designed and analyzed. Each resonator of the antenna is composed of two different dialectic materials stacked together. The aim of dual-segments is to get strong coupling with lower segment of high permittivity and wide impedance bandwidth with upper segment of lower permittivity. Quarter wave (λ/4) transformer is used to design corporate feed line with equally distributed power in each arm. With this setup a 10 dB return loss impedance bandwidth up to 19% (5 GHz-6.1 GHz) is achieved.Simulation of the four elements array antenna is performed using Computer Simulation Technology (CST 2010) and fabricated on Roger RO4003 substrate with ε_s= 3.38. A good agreement between simulation and measurements results is achieved.