Gain Enhancement in 2.4 GHz Rectangular Microstrip Antenna Arrays Using Hybrid Corporate– Series Feeding

Abstract

A robust antenna design that addresses the growing demand for compact, high-performance wireless devices remains a major challenge, particularly in achieving high antenna gain while maintaining compact size and acceptable bandwidth in microstrip antenna arrays. This paper presents the design, simulation, and performance analysis of rectangular microstrip antennas fed using different techniques at 2.4 GHz. Four antenna configurations were investigated: an inset-fed single-band rectangular microstrip antenna (RMSA), two corporate-fed RMSA arrays (1 × 2 and 1 × 4), and a 2 × 2 corporate–series-fed (hybrid-fed) RMSA array. All antenna dimensions and feed network parameters were optimized through parametric tuning using CST Studio Suite, guided by transmission-line model equations to achieve impedance matching, gain enhancement, and acceptable bandwidth performance. Simulation results show that show that the single-band antenna achieved an impedance bandwidth of 68.3 MHz (2.85% fractional bandwidth). The corporate-fed 1 × 4 array exhibited a bandwidth of 44.33 MHz (1.85%), while the 1 × 2 corporate-fed and 2 × 2 hybrid-fed arrays achieved bandwidths of 33.06 MHz (1.38%) and 50.41 MHz (2.26%), respectively. A comparative evaluation of antenna gains reveals that the hybrid-fed 2 × 2 RMSA array provides superior gain performance compared to the other configurations, demonstrating its effectiveness in overcoming the gain–bandwidth–size trade-off inherent in microstrip antenna arrays. The achieved bandwidth and gain characteristics make the proposed antenna suitable for compact ISM-band WLAN devices, while the array configurations are recommended for less size-constrained wireless applications.