Adaptive antennas at the mobile and base stations in an OFDM/TDMA system

TLDR

Smart antenna systems at base stations have demonstrated significant performance improvements in wireless communications. The study investigates joint adaptive antennas at base and mobile stations operating with orthogonal frequency‑division multiplexing. The authors derive exact joint optimal antenna weights for the base and mobile stations under cochannel interference in fading channels and validate the results with analytical expressions and Monte Carlo simulations. The proposed joint adaptive antenna system reduces average error probability, increases capacity, enables multiuser access across space, time, and subcarriers, and the derived optimal weights and simulation results confirm these performance gains.

Abstract

Several smart antenna systems have been proposed and demonstrated at the base station (BS) of wireless communications systems, and these have shown that significant system performance improvement is possible. We consider the use of adaptive antennas at the BS and mobile stations (MS), operating jointly, in combination with orthogonal frequency-division multiplexing. The advantages of the proposed system includes reductions in average error probability and increases in capacity compared to conventional systems. Multiuser access, in space, time, and through subcarriers, is also possible and expressions for the exact joint optimal antenna weights at the BS and MS under cochannel interference conditions for fading channels are derived. To demonstrate the potential of our proposed system, analytical along with Monte Carlo simulation results are provided.