A clustering technique for digital communications channel equalization using radial basis function networks

The application of a radial basis function network to digital communications channel equalization is examined. It is shown that the radial basis function network has an identical structure to the optimal Bayesian symbol-decision equalizer solution and, therefore, can be employed to implement the Bayesian equalizer. The training of a radial basis function network to realize the Bayesian equalization solution can be achieved efficiently using a simple and robust supervised clustering algorithm. During data transmission a decision-directed version of the clustering algorithm enables the radial basis function network to track a slowly time-varying environment. Moreover, the clustering scheme provides an automatic compensation for nonlinear channel and equipment distortion. Computer simulations are included to illustrate the analytical results.

[1]  Bernard Mulgrew,et al.  Complex-valued radial basic function network, Part I: Network architecture and learning algorithms , 1994, Signal Process..

[2]  John G. Proakis,et al.  Adaptive maximum-likelihood sequence estimation for digital signaling in the presence of intersymbol interference (Corresp.) , 1973, IEEE Trans. Inf. Theory.

[3]  S. A. Billings,et al.  Experimental design and identifiability for non-linear systems , 1987 .

[4]  David S. Broomhead,et al.  Multivariable Functional Interpolation and Adaptive Networks , 1988, Complex Syst..

[5]  Sheng Chen,et al.  Recursive hybrid algorithm for non-linear system identification using radial basis function networks , 1992 .

[6]  Richard O. Duda,et al.  Pattern classification and scene analysis , 1974, A Wiley-Interscience publication.

[7]  Shang-Liang Chen,et al.  Orthogonal least squares learning algorithm for radial basis function networks , 1991, IEEE Trans. Neural Networks.

[8]  Thomas L. Clarke,et al.  Generalization of neural networks to the complex plane , 1990, 1990 IJCNN International Joint Conference on Neural Networks.

[9]  Sammy Siu,et al.  Multilayer perceptron structures applied to adaptive equalisers for data communications , 1989, International Conference on Acoustics, Speech, and Signal Processing,.

[10]  Sheng Chen,et al.  Adaptive Bayesian decision feedback equaliser based on a radial basis function network , 1992, [Conference Record] SUPERCOMM/ICC '92 Discovering a New World of Communications.

[11]  S. Thomas Alexander,et al.  Adaptive Signal Processing , 1986, Texts and Monographs in Computer Science.

[12]  John Moody,et al.  Fast Learning in Networks of Locally-Tuned Processing Units , 1989, Neural Computation.

[13]  F. Girosi,et al.  Networks for approximation and learning , 1990, Proc. IEEE.

[14]  G. David Forney,et al.  Maximum-likelihood sequence estimation of digital sequences in the presence of intersymbol interference , 1972, IEEE Trans. Inf. Theory.

[15]  Donald F. Specht,et al.  Generation of Polynomial Discriminant Functions for Pattern Recognition , 1967, IEEE Trans. Electron. Comput..

[16]  G. J. Gibson,et al.  Application of Multilayer Perceptrons as Adaptive Channel Equalisers , 1990 .

[17]  G. J. Gibson,et al.  Adaptive channel equaliza-tion using a polynomial-perceptron structure , 1990 .

[18]  S. Qureshi,et al.  Adaptive equalization , 1982, Proceedings of the IEEE.

[19]  D. Broomhead,et al.  Radial Basis Functions, Multi-Variable Functional Interpolation and Adaptive Networks , 1988 .