Capacitively Coupled E-Shaped Broadband Microstrip Antenna

This paper presents air suspended broadband gap coupled E-shaped microstrip antenna. Single E-shaped microstrip antenna realizes impedance bandwidth of 152 MHz. Further bandwidth enhancement is achieved using gap coupling with parasitically coupled rectangular patch without slots. This configuration achieves bandwidth of about 171 MHz. Further, slots are cut inside the parasitically coupled rectangular patch and bandwidth of 201 MHz has been realized. The proposed antenna structure is designed and fabricated using FR4 substrate and suspended in air to improve the radiation characteristics. The antenna radiates in broadside direction. The antenna offers peak gain more than 9 dBi at lower frequency band which is the novelty in the proposed design. The fabricated antenna is tested and the measured results are presented. The detailed parametric analysis of proposed antenna has been carried out to optimize the dimensions of antenna. The equivalent circuit of antenna have been prepared and presented in this paper.