Title :
Super multi-carrier trellis coded 256 QAM digital microwave radio
Author :
Ohtsuka, Hiroyuki ; Saito, Yoichi ; Komaki, Shozo
Author_Institution :
Radio Commun. Syst. Lab., NTT, Kanagawa, Japan
fDate :
28 Nov-1 Dec 1988
Abstract :
Describes an outage-free 256-QAM (quadrature amplitude modulation) digital radio system. The degradation factors related to multipath fading and their countermeasure are discussed. Based on these considerations, supermulticarrier trellis-coded 256-QAM is proposed as a modulation scheme in multipath environments. The overall outage probability improvement factors derived from Rummler´s (1987) composite fade margin concept and linear amplitude dispersion (LAD) statistics are compared with the performance of the existing 256-QAM digital radio system. A preliminary laboratory experiment on eight-carrier 256-QAM signal transmission shows the validity of the predicted improvement. The study also shows one possible direction for digital radio systems for dispersive radio channels
Keywords :
amplitude modulation; digital communication systems; encoding; error detection codes; fading; microwave links; radiowave propagation; telecommunication channels; 256-QAM; composite fade margin concept; countermeasure; degradation factors; digital microwave radio; dispersive radio channels; laboratory experiment; linear amplitude dispersion; multicarrier trellis coded; multipath fading; outage probability improvement; quadrature amplitude modulation; signal transmission; statistics; Digital communication; Dispersion; Error correction codes; Fading; Laboratories; Modulation coding; Probability; Quadrature amplitude modulation; Radio communication countermeasures; Statistics;
Conference_Titel :
Global Telecommunications Conference, 1988, and Exhibition. 'Communications for the Information Age.' Conference Record, GLOBECOM '88., IEEE
Conference_Location :
Hollywood, FL
DOI :
10.1109/GLOCOM.1988.25844
