The Design of a 360°-Switched-Beam-Base Station Antenna

The concept of switched-beam antenna (SBA) systems covering an area of 360° for wireless base station applications is presented. First, a reconfigurable pattern antenna (RPA), which is composed of an omnidirectional slot-antenna array surrounded by an active cylindrical frequency selective surface (FSS), is studied. The behavior of FSS is controlled by PIN diodes which are able to divide the Azimuth plane into six sectors from one common source. Unfortunately for a sector antenna, a huge number of diodes are required which complicates the structure in terms of efficiency and complexity. However, a simple and an efficient SBA configuration based on a hexagonal Fabry-Pérot cavity leaky wave antenna (FPC LWA) arrays is proposed as a solution for RPA problems. A sector-directive beam is generated from a simple patch antenna embedded inside a resonant Fabry-Pérot cavity with specific dimensions which have an influence on beamwidth and radiation efficiency. To increase more sectorization level and channel’s capacity, the proposed sector in FPC LWA arrays can be divided into three subsectors by using an active high-impedance surface (HIS). As a conclusion, SBA based on FPC LWA is the most suitable solution for future wireless communications