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In recent years, reconfigurable antennas have been sought to improve the performance of multiple-input multiple-output (MIMO) wireless communication systems. Their ability to dynamically reconfigure their radiation pattern adds diversity in a manner that is not possible with fixed antennas. This paper investigates the performance benefits provided by pattern reconfigurable receiving antennas with uniform beam steering capability. Their potential performance is first estimated using simulations, and for the first time, the effect of uniform beam steering on MIMO system performance is evaluated in a real indoor channel using two electrically steerable passive array radiator (ESPAR) antennas. Performance comparison is made against a pair of monopole antennas using a hardware bit error rate (BER) test-bed that incorporates statistical spatial averaging in order to assess performance improvements in a more realistic way, and analyze the effect of antenna diversity on the overall system performance. The MIMO-ESPAR system reduces BER with certain pattern combinations and excels in capacity evaluations. The ESPAR antennas improve the spatially averaged channel capacity by as much as 37% at 10 dB transmit SNR, and gain an additional 1 bit/s/Hz in peak capacity at 10 dB receive SNR from diversity gain alone. These improvements make pattern reconfigurable antennas promising options in MIMO-related applications. [ABSTRACT FROM PUBLISHER]

Presents information on a study which investigated the effects of mutual coupling between the elements of an adaptive array on direct data domain algorithms. Methods of moments analysis; Effect of mutual coupling; Elimination of mutual coupling; Conclusions.

Presents a technique based on the Fourier transform for simultaneous extrapolation in the time and frequency domain. Extrapolation based on the discrete Fourier transform; Advantages of time-domain modeling; Drawback of frequency-domain formulations.

Extrapolates time-domain responses from three-dimensional conducting objects that arise in the numerical solution of electromagnetic field problems. Use of the matrix pencil approach; Basic equations; Real part of the frequency response; Total least-squares matrix pencil; Triangle patching of a disk; Early and late-time responses.