Design of high gain broadband microstrip patch antenna for UWB/X/Ku band applications

A miniature (20 mm × 14 mm × 1.6 mm) microstrip line fed broadband antenna with high gain is proposed in this research work. The proposed antenna exhibits −10 dB impedance bandwidth of 19.5 GHz (5 GHz-24.5 GHz) with a fractional bandwidth of 132% which covers major portion of UWB band (3.1 GHz −10.6 GHz), X band (8 GHz-12 GHz), Ku band (12 GHz-18 GHz) and large part of K band (18 GHz-27 GHz).A single layer frequency selective surface (FSS) is integrated with the proposed antenna to enhance the gain of 5.9 dBi over the entire frequency band. 6 × 6 FSS layer (52.8 mm × 52.8 mm × 1.6 mm) is kept below the proposed antenna at suitable distance without hampering the reflection coefficient and flat gain characteristics of the antenna. Proposed antenna and FSS structure are designed and simulated by using CST Microwave Studio simulator and both are built on FR-4 substrate of 1.6 mm thickness with relative dielectric constant (εr) of 4.4, loss tangent (tanδ) of 0.02. The overall dimension of the proposed FSS integrated antenna is 52.8 mm × 52.8 mm × 21.2 mm, which is highly relevant for high-gain applications. Simulated results are validated experimentally by standard Microwave Test bench.