Title :
Constant modulus blind equalisation algorithms under soft constraint satisfaction
Author :
Tanrikulu, O. ; Baykal, Buyurman ; Constantinides, Anthony G. ; Chambers, Jonathon A.
Author_Institution :
Dept. of Electr. & Electron. Eng., Imperial Coll. of Sci., Technol. & Med., London, UK
Abstract :
New constant modulus (CM) algorithms are presented that are based on soft constraint satisfaction. The stationary points of an algorithm in this family are studied for an AR(p) channel and it is shown that Ding-type undesirable local solutions (ULS) do not exist. This is due to the normalisation of the gradient vector and the soft nonlinearity used in these algorithms. Error performance surfaces (EPS) and convergence trajectories from arbitrary initialisations are presented for various channels that support the analytical findings
Keywords :
adaptive equalisers; autoregressive processes; convergence of numerical methods; digital communication; error analysis; telecommunication channels; AR(p) channel; CM algorithms; Ding-type undesirable local solutions; autoregressive channels; constant modulus blind equalisation algorithms; convergence trajectories; error performance surfaces; gradient vector; initialisations; normalisation; soft constraint satisfaction; soft nonlinearity; stationary points; Baseband; Biomedical signal processing; Blind equalizers; Decision feedback equalizers; Digital signal processing; Digital systems; Educational institutions; Equations; Lagrangian functions; Signal processing algorithms;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1997. ICASSP-97., 1997 IEEE International Conference on
Conference_Location :
Munich
Print_ISBN :
0-8186-7919-0
DOI :
10.1109/ICASSP.1997.599607
