Computational analysis of a dual‐port semi‐circular patch antenna combined with Koch curve fractals for ultra‐wideband systems

Abstract

Abstract This paper presents a two‐port microstrip‐fed semi‐circular patch antenna integrated with Koch curve fractals and common ground with defected ground structure for the effective implementation in handheld ultra‐wideband (UWB) systems. The proposed array is engraved on a 1.57 mm thick FR‐4 substrate with an overall array size of 30.5 × 47 × 1.64 mm3. The parametric analysis of the proposed array indicates that the two optimized Koch curve fractal (second iteration order) radiators (upper substrate layer) provides an optimum matching performance in a wide operational band (4.395–10.184 GHz, 79.4%) and minimizes the patch area by 41.2% as compared to the conventional circular patch. To realize good port‐to‐port isolation (S21/S12 ≤ −16.8 dB), the reduced ground is slotted and incorporated with a funnel‐shaped decoupling structure at the center. The prototype of the proposed array is fabricated and experimentally tested to justify the simulated S‐parameter results. All diversity metrics like envelope correlation coefficient, diversity gain (DG), mean effective gain, channel capacity loss, and total active reflection coefficient lie within their acceptable limits which affirm a high signal‐to‐noise ratio and the proficiency of the proposed array in the development of high data‐rate UWB communication devices.

Keywords

• defected ground structure (DGS)
• Koch curve fractal
• multiple‐input multiple‐output (MIMO)
• ultra‐wideband (UWB)