Smart antennas for wireless communications

Over the last decade, there has been a growing interest in improving system capacity and increasing coverage area in wireless communications using smart antennas. Smart antenna technology is being considered for mobile platforms such as automobiles, cellular telephones (mobile unit), and laptops. This paper presents the design of a smart antenna along with the associated signal processing algorithms for use in the next generation 20 GHz wireless communications systems. The results presented here are part of a broader project that considers this antenna system in the context of reconfigurable broadband (high-speed) networks. This paper concentrates only on the antenna design and on the development of efficient adaptive algorithms for beamforming and direction-of-arrival (DOA). The objective is to design an adaptive antenna that directs the maximum radiation of the antenna pattern toward the signal-of-interest (SOI), and places nulls toward the signal-not-of-interest (SNOI). The proposed antenna design and associated beamforming algorithms take into account mutual coupling for greater accuracy.