• Publications
  • Influence
The Gauss-Seidel fast affine projection algorithm
This paper investigates the implementation of Gauss-Seidel iterations using the logarithmic number system (LNS) and shows that the algorithm is only marginally more complex than NLMS and simpler than other FAP algorithms. Expand
Iterative Channel Estimation, Equalization, and Decoding for Pilot-Symbol Assisted Modulation Over Frequency Selective Fast Fading Channels
  • M. Flanagan, A. Fagan
  • Mathematics, Computer Science
  • IEEE Transactions on Vehicular Technology
  • 16 July 2007
A pilot-based channel estimation scheme is proposed for frequency selective Rayleigh fading channels which work in conjunction with the existing paradigm of turbo equalization, providing an attractive low-complexity alternative to iterative receivers based on state-space models for channel parameter evolution. Expand
A Versatile Variable Rate LDPC Codec Architecture
This paper presents a system architecture for low-density parity-check (LDPC) codes that allows dynamic switching of LDPC codes within the encoder and decoder without hardware modification of theseExpand
Minimum mean-squared error impulse response shortening for discrete multitone transceivers
We reformulate the minimum mean squared error (MMSE) solution for time domain equalization (TEQ) in multitone transceivers. We show that the maximum shortening signal-to-noise ratio (MSSNR) andExpand
Optimal Wavelet Packet Modulation under finite complexity constraint
It is found that optimal-WPM outperforms conventional multichannel systems of equal complexity for ISI channels and derives operating conditions for the capacity-optimal tree for a given communication channel and power budget. Expand
The Gauss-Seidel pseudo affine projection algorithm and its application for echo cancellation
  • F. Albu, A. Fagan
  • Mathematics
  • The Thrity-Seventh Asilomar Conference on Signals…
  • 9 November 2003
In this paper we propose a new approach for adaptive echo cancellation: the Gauss-Seidel pseudo affine projection algorithm (GSPAP). It is proved by simulations that it is stable, fast convergent andExpand
Adaptive Nonlinear Narrow Band Interference Rejection in Ternary DS-UWB
  • B. Gaffney, A. Fagan
  • Computer Science
  • IEEE International Conference on Communications
  • 11 December 2006
This paper derives the optimum nonlinear function for a ternary DS-UWB system, and applies it to a LMS rejection filter, and the introduction of an interleaver eliminates the need for the symbols received during the filters training period to be discarded. Expand
An edge classification based approach to the post-processing of transform encoded images
A computationally-efficient edge classifier, employing a histogram treatment of image sub-blocks, is proposed, which forms the basis of an adaptive, non-linear postprocessing algorithm incorporating adaptive /spl alpha/-trimmed mean filtering and a transform domain dithering technique. Expand
A minimum mean-squared error interpretation of residual ISI channel shortening for discrete multitone transceivers
It is demonstrated that allowing DIR adaptation achieves a minimisation of the effective impulse response energy outside the desired window of v samples, equivalent to a minimum mean-squared error (MMSE) solution to the channel-shortening problem. Expand
Demonstrating Doubly-Differential Quadrature Phase Shift Keying in the Optical Domain
This method is more robust against high frequency offsets (FO) than conventional single differential quadrature phase shift keying (SDQPSK) with offset compensation and has lower computational requirements than other FO compensation methods. Expand