Wireless Personal Communications

, Volume 52, Issue 4, pp 693–707 | Cite as

A Novel FRFT Beamformer for Rayleigh Faded Channels

Article

Abstract

A method of optimal beamforming for flat Rayleigh faded channels using the Fractional Fourier Transform (FRFT) is considered in this paper. It has been demonstrated through simulations that optimal beamforming with FRFT allows smaller mean-square errors in restoring signals degraded with linear time-or frequency variant distortions and Additive White Gaussian Noise. This is made possible by the additional flexibility that comes with free parameter ‘a’ of the fractional Fourier transform as oppose to the classical Fourier transform (FT). The method is especially useful in moving source problems, where Doppler Effect produces frequency shift when the source is moving, as in mobile and wireless communication where user produces the frequency shift while moving. In this paper it is shown through simulations that beamforming in fractional domain reduces BER as compared to time or frequency domain.

Keywords

Beamforming Fractional fourier transform Time frequency varying channels 

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Copyright information

© Springer Science+Business Media, LLC. 2008

Authors and Affiliations

  1. 1.Department of Electronics and Communication EngineeringThapar Institute of Engineering and TechnologyPatialaIndia
  2. 2.Department of Electronics and CommunicationJaypee Institute of Engineering and Technology (JIET)GunaIndia

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