Effect of superstrate material on a high‐gain antenna using array of parasitic patches

Abstract

This article highlights the effect of superstrate material on a high-gain antenna using array of parasitic patches for wireless applications. The antenna structure consists of a microstrip antenna, which feeds an array of square parasitic patches fabricated on a ceramic or FR4 superstrate. The patches on a superstrate are suspended in air at k 0 /2. The spacing between parasitic patches and patch dimensions decrease with dielectric constant and, thus, a compact antenna with almost same gain can be designed with high dielectric superstrate. The structures with 5 Â 5 array of square parasitic patches provide a gain of 17.5 dB on infinite ground plane in both the cases but the array dimension is 55 Â 55 mm 2 in ceramic as compared to 115 Â 115 mm 2 Antenna with ceramic superstrate on finite ground requires 25% less ground plane size as compared to FR4. Structure with FR4 superstrate is designed, fabricated, and tested. The measured VSWR is <2 over 5. 725-5.875 GHz frequency band. The antenna with 5 Â 5 array of square parasitic patches provides a gain of 18.0 dB with 92% efficiency, SLL of À18.4 dB, and front to back lobe ratio of more than 20 dB. The proposed structure can be packaged inside an application platform.

Efficient high gain with low sidelobe level antenna structures using circular array of square parasitic patches on a superstrate layer

“…Gain also depends on the separation between PP and FP. Maximum gain is obtained when the spacing between the patches is about 0.5 λ o with square PP dimensions of 12 mm that correspond to approximately λ/2, where λ is the wavelength in a corresponding dielectric superstrate at 5.8 GHz [32].…”

“…It is observed that a superstrate layer has a focusing effect. The phase distributions of the fields with a superstrate are observed to be more uniform than the one without the superstrate, leading to an increase in effective aperture area and gain [19, 31, 32].…”

A novel design of Fabry-Perot antenna using metamaterial superstrate for gain and bandwidth enhancement

“…As it is concluded from Table 2 Therefore, metamaterial elements on a dielectric as PRS are fabricated to enhance the reflection coefficient and the directivity. Gain and bandwidth are functions of reflection coefficient in FP cavity as follow [15,29]:…”

“…However, main disadvantage of these antennas is their narrow bandwidth [15][16][17]. This is the fundamental limitation of antenna gain enhancement with FP structures.…”

An Uwb Fractal Antenna With Defected Ground Structure and Swastika Shape Electromagnetic Band Gap

“…The gain of any antenna can be increased by EBG structure in the frequency band where the EBG structure is having high surface impedance behaviour or band stop property such that in that band the propagation of surface wave is suppressed which improves the antenna gain or radiated power [16]. Gain of an antenna can be kept constant by using higher permittivity substrate in comparison to low permittivity substrate and by using a superstrate layer of array of patches (like EBG structures) [17]. EBG is also used to get notched characteristic in ultra wideband antenna [18,19].…”