Improve spectrum efficiency based on variable-power AMC and ARQ for OFDM systems

Author

Chu, Yung-Hung ; Kuo, Yu-Chin ; Tseng, Shu-Ming ; Hsu, Yueh-Teng

Author_Institution

Dept. of Electron. Eng., Nat. Taipei Univ. of Technol., Taipei, Taiwan

fYear

2010

fDate

22-24 Oct. 2010

Firstpage

829

Lastpage

831

Abstract

To improve spectrum efficiency (SE), the adaptive modulation and coding (AMC) and automatic repeat request (ARQ) scheme have been combined for OFDM systems. In this paper, we add variable power subject to power constraint in each AMC mode. We use KKT optimization algorithm to get the optimal transmit power and AMC mode boundaries. The numerical results show that the average SE is increased by about 0.3 bits/sec/Hz for OFDM systems with Nakagami fading with parameter m=2 when SNR is around 15dB and the retransmission is once.

Keywords

Nakagami channels; OFDM modulation; adaptive codes; adaptive modulation; automatic repeat request; optimisation; radio spectrum management; AMC; ARQ; KKT optimization algorithm; Nakagami fading; OFDM systems; SE; adaptive modulation and coding; automatic repeat request; power transmission; spectrum efficiency; Adaptation model; Automatic repeat request; Signal to noise ratio; OFDM; spectrum efficiency; transmitter power control;

fLanguage

English

Publisher

ieee

Conference_Titel

Intelligent Computing and Integrated Systems (ICISS), 2010 International Conference on

Conference_Location

Guilin

Print_ISBN

978-1-4244-6834-8

Type

conf

DOI

10.1109/ICISS.2010.5657084

Filename

5657084