Air suspended Multiband E-shaped Microstrip Antenna

This paper includes analysis and design of broadband defected ground plane E shaped multiband microstrip antenna achieved by modifying the reported configuration of triple band E-shaped microstrip antenna. The paper also covers design of air suspended triple band defected ground E shaped antenna with modal analysis. The bandwidth of the antenna is enhanced by incorporating slight modifications in the reported configuration of E-shaped patch antenna. The surface current/field distribution at higher order resonant modes are perturbed by including slots on both patch and ground which results in respective modal frequencies reduction. The fundamental mode and TM12 together gives broadband response. The slots aid in attaining radiation pattern at higher order modes similar to the fundamental mode frequency. Also gain improvement is achieved with the suspended configuration of the proposed antenna. The antenna yields 5dbi gain at second resonant frequency. Formulation for higher order resonant mode length is also proposed in the paper.