A Progressive Group Detection-Assisted Near-Optimal Iterative Chip-Level Decision Feedback Equalizer
Konferenz: European Wireless 2014 - 20th European Wireless Conference
14.05.2014 - 16.05.2014 in Barcelona, Spain
Tagungsband: European Wireless 2014
Seiten: 6Sprache: EnglischTyp: PDFPersönliche VDE-Mitglieder erhalten auf diesen Artikel 10% Rabatt
Badawi, Karim; Huang, Qiuting (Integrated Systems Laboratory, ETH Zurich, 8092 Zurich, Switzerland)
Burg, Andreas (Telecommunications Circuits Laboratory, EPF Lausanne, 1015 Lausanne, Switzerland)
In this paper, a novel decision-feedback equalizer (DFE) with progressive group detection (PGD) assistance is proposed for the downlink of synchronous code division multiple access (CDMA) multiuser wireless systems. The proposed DFE operates on chip-level to accommodate wideband systems employing long scrambling codes over frequency-selective channels. PGD is a near-maximum likelihood (ML) detection technique that spans and intelligently prunes the set of possible transmit-symbol combinations, and provides a set of the most probable combinations as interim hypotheses for symbol-decisions to the DFE in order to circumvent the initial chip-decisions availability problem and avert faulty feedback. The receiver exhibits an iterative architecture to further enhance the performance. Simulation results for the 3GPP high-speed packet access (HSPA) show that the proposed receiver outperforms linear and DFE receivers found in literature, and provides substantial performance gains that scale with complexity. The proposed receiver’s performance approaches that of the single-code ideal DFE.