Beam Pattern Scanning (BPS) versus Space-Time Block Coding (STBC) and Space-Time Trellis Coding (STTC)
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Abstract
In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (also called beam pattern oscillation), controlled time varying weight vectors are applied to the antenna array elements mounted at the base station (BS). This creates a small movement in the antenna array pattern directed toward the desired user. In rich scattering environments, this small beam pattern movement creates an artificial fast fading channel. The receiver is designed to exploit time diversity benefits of the fast fading channel. Via the application of simple combining techniques, BPS improves the probability-of-error performance and network capacity with minimal cost and complexity. In this work, to highlight the potential of the BPS, we compare BPS and Space-Time Coding (i.e., STBC and STTC) schemes. The comparisons are in terms of their complexity, system physical dimension, network capacity, probability-of-error performance, and spectrum efficiency. It is shown that BPS leads to higher network capacity and performance with a smaller antenna dimension and complexity with minimal loss in spectrum efficiency. This identifies BPS as a promising scheme for future wireless communications with smart antennas.
- S. M. Alamouti, “A simple transmit diversity technique for wireless communications,” IEEE Journal on Selected areas in Communications, Vol. 16, No. 8, pp. 1451–1458, 1998.
- V. Tarokh, H. Jafarkhani, and A. R. Calderbank, “Space-time block codes from orthogonal designs,” IEEE Transactions on Information Theory, Vol. 45, No. 5, pp. 1456–1467, July 1999.
- V. Tarokh, N. Seshadri, and A. R. Calderbank, “Space-time codes for high data rate wireless communication: Performance criterion and code construction,” IEEE Transactions on Information Theory, Vol. 44, pp. 744–765, March 1998.
- V. Tarokh, A. F. Naguib, N. Seshadri, and A. Calderbank, “Space-time codes for high data rate wireless communi-cations: Performance criteria in the presence of channel estimation errors, mobility, and multiple paths,” IEEE Transactions on Communications, Vol. 47, No. 2, Febru-ary 1999.
- A. F. Naguib, V. Tarokh, N. Seshadri, and A. R Calderbank, “A space-time coding modem for high-data-rate wireless communications,” IEEE Journal on Selected Areas in Communications, Vol. 16, No. 8, October 1998.
- N. Seshadri and J. H. Winters, “Two signaling schemes for improving the error performance of frequency division-duplex transmission system using transmitter an-tenna diversity,” International Journal Wireless Informa-tion Networks, Vol. 1, No. 1, pp. 49–60, January 1994.
- J. H. Winters, “The diversity gain of transmit diversity in wireless systems with Rayleigh fading,” in Proceedings of the 1994 ICC/SUPERCOMM, New Orleans, Vol. 2, pp. 1121–1125, May 1994.
- R. W. Heath, S. Sandhu, and A. J. Paulraj, “Space-time block coding versus space-time trellis codes,” Proceed-ings of IEEE International Conference on Communica-tions, Helsinki, Finland, June 11–14, 2001.
- V. Tarokh, A. Naguib, N. Seshadri, and A. R. Calderbank, “Combined array processing and space-time coding,” IEEE Transactions on Information Theory, Vol. 45, No. 4, pp. 1121–1128, May 1999.
- S. A. Zekavat and C. R. Nassar, “Antenna arrays with oscillating beam patterns: Characterization of transmit diversity using semi-elliptic coverage geometric-based stochastic channel modeling,” IEEE Transactions on Communications, Vol. 50, No. 10, pp. 1549–1556, Octo-ber 2002.
- S. A. Zekavat, C. R. Nassar, and S. Shattil, “Oscillating beam adaptive antennas and multi-carrier systems: Achieving transmit diversity, frequency diversity and di-rectionality,” IEEE Transactions on Vehicular Technol-ogy, Vol. 51, No. 5, pp. 1030 –1039, September 2002.