Length- and cost-dependent local minima of unconstrained blind channel equalizers
- 1 November 1996
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Signal Processing
- Vol. 44 (11) , 2726-2735
- https://doi.org/10.1109/78.542179
Abstract
-Baud-rate linear blind equalizers may converge to undesirable stable equilibria due to different mechanisms. One such mechanism is the use of linear FIR filters as equalizers. In this paper, it is shown that this type of local minima ex- ist for all unconstrained blind equalizers whose cost functions satisfy two general conditions. The local minima generated by this mechanism are thus called length-dependent local minima. Another mechanism is generated by the cost function adopted by the blind algorithm itself. This type of local minima are called cost-dependent local minima. It shall be shown that several well- designed algorithms do not have cost-dependent local minimum, whereas other algorithms, such , the decision-directed equalizer and the stop-and-go algorithm (SGA), do. Unlike many existing convergence analysis, the convergence of the Godard algorithms (GA’s) and standard cumulant algorithms @CA’s) under Gauss- ian noise is also presented here. Computer simulations are used to verify the analytical results.Keywords
This publication has 23 references indexed in Scilit:
- Convergence analysis of finite length blind adaptive equalizersIEEE Transactions on Signal Processing, 1995
- On the (non)existence of undesirable equilibria of Godard blind equalizersIEEE Transactions on Signal Processing, 1992
- Ill-convergence of Godard blind equalizers in data communication systemsIEEE Transactions on Communications, 1991
- Stationary points of the constant modulus algorithm for real Gaussian signalsIEEE Transactions on Acoustics, Speech, and Signal Processing, 1990
- ARMA bispectrum approach to nonminimum phase system identificationIEEE Transactions on Acoustics, Speech, and Signal Processing, 1988
- Blind Equalization and Carrier Recovery Using a "Stop-and-Go" Decision-Directed AlgorithmIEEE Transactions on Communications, 1987
- Convergence analysis of self-adaptive equalizersIEEE Transactions on Information Theory, 1984
- Analysis of Decision-Directed Equalizer ConvergenceBell System Technical Journal, 1980
- Self-Recovering Equalization and Carrier Tracking in Two-Dimensional Data Communication SystemsIEEE Transactions on Communications, 1980
- A Method of Self-Recovering Equalization for Multilevel Amplitude-Modulation SystemsIEEE Transactions on Communications, 1975