Title :
Efficient adaptive modulation and power allocation algorithm for OFDMA cellular systems
Author_Institution :
Dept. of Electr. & Electron. Eng., Yonsei Univ., Seoul, South Korea
fDate :
April 28-30, 2005
Abstract :
An adaptive transmission scheme using QAM and LDPC code is proposed for an OFDMA cellular system employing FDD. Also, adaptive algorithms for active user selection, subchannel transmission power allocation, and modulation and coding set selection are proposed. The performance of the proposed scheme is obtained from computer simulation and is compared with that of the conventional scheme using mean SNR only. It is shown that the proposed scheme can provide up to 5.1 dB gain over the conventional scheme at the expense of only 3 more bits in feedback information.
Keywords :
OFDM modulation; adaptive codes; adaptive modulation; cellular radio; channel allocation; frequency division multiple access; modulation coding; parity check codes; FDD; LDPC code; OFDMA cellular system; QAM; active user selection; adaptive transmission scheme; frequency division duplexing; low-density parity check code; modulation coding set selection; quadrature amplitude modulation; subchannel transmission power allocation; Channel state information; Decoding; Feedback; Information technology; Modulation coding; OFDM modulation; Parity check codes; Power system modeling; Quality of service; Radio transmitters;
Conference_Titel :
Wireless Telecommunications Symposium, 2005
Print_ISBN :
0-7803-8856-9
DOI :
10.1109/WTS.2005.1524783
