A compact broadband switched beam antenna with 360° multibeam scanning/omnidirectional coverage

A compact switched beam antenna (SBA) capable of achieving 360° multibeam azimuth scanning and omnidirectional coverage is presented. The SBA consists of two vertically stacked cylindrical Luneberg lens antennas (CLLAs) with a low-profile inverted-cap shaped printed monopole placed above them. Each CLLA yields multiple highly directive beams and 180° scan coverage by implementing an arc feeding array of 11-element Vivaldi antennas at the periphery of the lens. The desired refractive index of the lens is controlled through the asymmetric Bruggeman (A-BG) effective medium theory and realized by a combination of three types of holes in a homogeneous dielectric base. The optimized SBA achieves a wide impedance bandwidth over 2.5-13GHz, and it's azimuth radiation pattern is switch selectable between omnidirectional coverage with 0dBi gain over 2.5-8.5GHz band and 360° steering coverage with about -3dB crossover and tolerable gain drop over 3.5-10GHz band. It can be easily applied to the line-of-sight data link and Local Multipoint Communication Systems (LMCS).