Adaptive minimum bit error rate beamforming assisted receiver for QPSK wireless communication

doi:10.1016/j.dsp.2005.03.001

Digital Signal Processing

Volume 15, Issue 6, November 2005, Pages 545-567

https://doi.org/10.1016/j.dsp.2005.03.001 Get rights and content

Abstract

This paper considers interference limited communication systems where the desired user and interfering users are symbol-synchronized. A novel adaptive beamforming technique is proposed for quadrature phase shift keying (QPSK) receiver based directly on minimizing the bit error rate. It is demonstrated that the proposed minimum bit error rate (MBER) approach utilizes the system resource (antenna array elements) more intelligently, than the standard minimum mean square error (MMSE) approach. Consequently, an MBER beamforming assisted receiver is capable of providing significant performance gains in terms of a reduced bit error rate over an MMSE beamforming one. A block-data based adaptive implementation of the theoretical MBER beamforming solution is developed based on the classical Parzen window estimate of probability density function. Furthermore, a sample-by-sample adaptive implementation is also considered, and a stochastic gradient algorithm, called the least bit error rate, is derived for the beamforming assisted QPSK receiver.

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Adaptive minimum bit error rate beamforming assisted receiver for QPSK wireless communication

Abstract

Signal Process.

Math. Comput. Modeling

Signal Process.

The impact of antenna diversity on the capacity of wireless communication systems

IEEE Trans. Commun.

Increasing the capacity of GSM cellular radio using adaptive antennas

IEE Proc. Commun.

Digital Beamforming in Wireless Communications

Applications of antenna arrays to mobile communications, Part I: Performance improvement, feasibility, and system considerations

Proc. IEEE

Applications of antenna arrays to mobile communications, Part II: Beam-forming and direction-of-arrival considerations

Proc. IEEE

Space-time processing for wireless communications

IEEE Signal Process. Mag.

Smart antennas for wireless systems

IEEE Personal Commun.

Spatial and temporal communication theory using adaptive antenna array

IEEE Personal Commun.

Capacity enhancement using adaptive arrays in an AMPS system

IEEE Trans. Vehicular Technol.

Smart antennas for mobile communication systems: benefits and challenges

IEE Electron. Commun. J.

Third Generation Systems and Intelligent Wireless Networking—Smart Antennas and Adaptive Modulation

Intelligent antenna system for cdma2000

IEEE Signal Process. Mag.

Rapid convergence rate in adaptive arrays

IEEE Trans. Aerospace Electron. Syst.

Convergence of the SMI and the diagonally loaded SMI algorithms with weak interference (adaptive array)

IEEE Trans. Antennas Propagation

Adaptive antenna systems

Proc. IEEE

A simple adaptive algorithm for real-time processing in antenna arrays

Proc. IEEE

Adaptive Filter Theory