A Switched Beam Antenna with Pattern Diversity for Wi-Fi Applications

This paper proposes a cost-effective and compact design for a switched-beam antenna system intended to enhance spatial diversity in wireless communications. The antenna supports a set of four distinct radiation patterns, herein referred to as the beam-set. This set comprises one broadside directive beam, two symmetrical tilted directive beams, and a conical beam pattern, collectively providing comprehensive angular coverage suitable for multipath environments. The spatial correlation among the beams is evaluated using the Clarke correlation coefficient, demonstrating low mutual correlation across the beam-set. This characteristic is critical for space diversity applications, as it enables the system to exploit independent fading channels, thereby improving signal robustness and link reliability. The proposed design is particularly suited for IEEE 802.11 (Wi-Fi) systems, where channel fading and interference can significantly degrade performance, especially in complex indoor or urban scenarios. The antenna ability to provide multiple, low-correlation directive beams without the need for complex beamforming algorithms or expensive hardware makes it a practical solution for low-cost, high-performance wireless deployments.