Abstract: The global acceptance of cellular technology or personal communication service raised the wireless communication beyond all the expectations. But this led to the shortage of the number of radio frequencies that can be utilized thereby increasing the cost of few remaining licenses to use these frequencies to manifold. With emerging techniques that provided voice, data and multimedia facilities in an extensive range, space was the final frontiers. Spatial division is the only promising multiple access technique that is successful in providing capacity, coverage and quality. For many years, antennas were most neglected part in mobile communication. But with the need of spatial division, advancement of antenna led to the evolution of smart antenna. The goal of this paper is to study what is smart antenna, what makes it smart and efficient from Omni directional antenna and how its implementation made the communication system more efficient.

Keywords: Adaptive Array Antenna; Delay Spread; Fading; SDMA; Smart antenna; Switched Beam Antenna.