Modified 128-QAM Constellation Schemes Allowing Low-complexity Non-Data-Aided Carrier Recovery
Konferenz: PIMRC 2005 - 16th Annual IEEE International Symposium on Personal Indoor and Mobile Radio Communications
11.09.2005 - 14.09.2005 in Berlin, Germany
Tagungsband: PIMRC 2005
Seiten: 5Sprache: EnglischTyp: PDFPersönliche VDE-Mitglieder erhalten auf diesen Artikel 10% Rabatt
Hou, Hsin-An (Computer & Communications Research Laboratories, Industrial Technology Research Institute, Chutung, Hsinchu, Taiwan, ROC)
Squared M-ary quadrature amplitude modulation (QAM) constellations have been widely adopted for modern high-data-rate digital communications. Nevertheless, carrier recovery required by demodulation of 128-QAM signals is almost a formidable task for practical receiver design. In this paper, two types of modified 128-QAM constellations are proposed allowing utilization of a low-complexity carrier recovery mechanism in the receiver. With the proposed constellations, perfect recovery of a frequency offset up to ±2.5% of baud rate is guaranteed using a conventional carrier recovery method at the expense of slight Es/N0 and PAPR increment compared with the conventional 128-QAM constellations.