Nonrecursive adaptive decision-feedback equalization from channel estimates

The performance and complexity of channel estimate-based equalizer adaptation are considered. It is shown via simulation of terrestrial mobile radio channels that both initialization and tracking performance of a fractionally spaced decision feedback equalizer (DFE) are improved over conventional, recursive adaptation algorithms. A plausible explanation for the improvement is provided, and the computational requirements of this approach are compared with those of conventional adaptation methods. Those requirements can be minimized by taking advantage of the structure of the DFE coefficient equations. The complexity is compared with that of a conventional adaptive DFE.<<ETX>>

[1]  Mushfiqur Rahman,et al.  A new channel estimator for fast start-up equalization , 1991, IEEE Trans. Commun..

[2]  T. Kailath,et al.  Fast, recursive-least-squares transversal filters for adaptive filtering , 1984 .

[3]  David D. Falconer,et al.  Adaptive Equalization Techniques for HF Channels , 1987, IEEE J. Sel. Areas Commun..

[4]  Asrar U. H. Sheikh,et al.  Adaptive equalization and diversity combining for a mobile radio channel , 1990, [Proceedings] GLOBECOM '90: IEEE Global Telecommunications Conference and Exhibition.

[5]  T. Kailath,et al.  Numerically stable fast transversal filters for recursive least squares adaptive filtering , 1991, IEEE Trans. Signal Process..

[6]  N. Al-Dhahir,et al.  Fast algorithms for the computation of the finite length decision feedback equalizer , 1992, [Proceedings] ICASSP-92: 1992 IEEE International Conference on Acoustics, Speech, and Signal Processing.

[7]  John M. Cioffi,et al.  When Do I Use An RLS Adaptive Filter ? , 1985, Nineteeth Asilomar Conference on Circuits, Systems and Computers, 1985..

[8]  H. Meyr,et al.  An investigation of channel estimation and equalization techniques for moderately rapid fading HF-channels , 1991, ICC 91 International Conference on Communications Conference Record.

[9]  David D. Falconer,et al.  Tracking properties and steady-state performance of RLS adaptive filter algorithms , 1986, IEEE Trans. Acoust. Speech Signal Process..

[10]  Dominique Godard,et al.  Channel equalization using a Kalman filter for fast data transmission , 1974 .

[11]  John M. Cioffi,et al.  A comparison of least squares and gradient adaptive equalization for multipath fading in wideband digital mobile radio , 1989, IEEE Global Telecommunications Conference, 1989, and Exhibition. 'Communications Technology for the 1990s and Beyond.

[12]  P.A.M. Bune.  A low-effort DSP equalization algorithm for wideband digital TDMA mobile radio receivers , 1991, ICC 91 International Conference on Communications Conference Record.

[13]  Edward J. Wegman,et al.  Statistical Signal Processing , 1985 .

[14]  John G. Proakis.  Adaptive Equalization for TDMA Digital Mobile , 1991 .