Decision-Directed (DD) equalization is the most primitive Blind Equalization (BE) method forthecancelling of Inter-Symbol-Interference (ISI) in data communication systems. Even though DD equalizers are believed to be unable to open the channel eye when it is initially closed, this does not seem to be true in the case of Constant-Modulus (CM) constellations (pure phase modulation). We investigate the shape of the DD cost function in this case and obtain several interesting results that indicate that the DD algorithm should be capable of opening a closed channel eye in the CM case. Based on this fact, we propose a novel hybrid CMA-DD equalization scheme that others an appealing alternative to the Generalized Sato (GSATO) algorithm for QAM constellations. Our theoretical claims about the performance of DDequalizers as well as the performance of our novel scheme are verified through computer simulations.
On the decision-directed equalization of constant modulus signals
Asilomar 1994, 28th IEEE Annual Asilomar Conference on Signals, Systems and Computers, October 31-November 2, 1994, Pacific Grove, USA
Systèmes de Communication
© 1994 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
PERMALINK : https://www.eurecom.fr/publication/532