Investigation on Wideband E-Shaped Microstrip Patch Antenna with Dielectric Superstrate
V. Saidulu1, K. Srinivasa Rao2, P. V. D. Somasekhar Rao3

1V. Saidulu, Department of Electronics and Communication, MGIT, Hyderabad (Telangana), India.
2K. Srinivasa Rao, Department of Electronics and Communication, VIFCET, Hyderabad (Telangana), India.
3P. V. D. Somasekhar Rao, Department of Electronics and Communication, JNTUH, Hyderabad (Telangana), India.

Manuscript received on 15 April 2015 | Revised Manuscript received on 25 April 2015 | Manuscript Published on 30 April 2015 | PP: 240-244 | Volume-4 Issue-4, April 2015 | Retrieval Number: D3976044415/15©BEIESP
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© The Authors. Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP). This is an open access article under the CC-BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Abstract: This paper describes the effect of the superstrates on bandwidth and gain of E-shaped microstrip patch antenna without superstrate and loaded with dielectric superstrates. It is found that there is a degradation in the performance of the antenna when the superstrate is touching the patch antenna i.e its height above the patch antenna (H) =0 mm. Further, it is also observed that the degraded performance characteristics of the patch antenna can be improved by placing the superstrates at optimum height (H) =Hopt. The microstrip patch antenna without dielectric superstrate has an impedance bandwidth of 0.17GHz (SWR 2) at 2.04 GHz, gain is 8.67 dB and return-loss is -19.95 dB. When the superstrate is placed touching the patch antenna, the resonant frequency is reduced to 1.59 GHz from 2.04 GHz and bandwidth is reduced 0.15 GHz (SWR ≤ 2) at 1.59 GHz, gain is decreased by about 0.92% (0.08 dB) for Ԑr= 2.2 to 39.5% (3.47 dB) for Ԑr= 10.2. As the height of the superstrate is increased, the performance of the patch antenna improves and at a particular optimum height the gain for all the superstrates will be closer to the free space radiation conditions of the patch antenna without superstate. But the resonant frequency decreases with increase in Ԑr2. The variation in the return-loss for H = Hopt. is within ± 1.5 dB of the free space radiation condition for all the dielectric constant of the superstrate and it is within acceptable limits. The bandwidth improves (12%) for Ԑr2 up to 4.8. However, the bandwidth decreases for Ԑr2= 10.2. There is a good agreement between simulated and measured results.
Keywords: E-Shaped Patch Antenna, Superstrate, Bandwidth And Axial Ratio Etc.

Scope of the Article: Microwave Antenna