Title :
Capacity of clipped 4-QAM-OFDM
Author :
Fischer, Robert F R
Author_Institution :
Lehrstuhl fur Informationsubertragung, Friedrich-Alexander-Univ. Erlangen-Nurnberg, Erlangen, Germany
Abstract :
The capacity of OFDM with 4-QAM modulation per carrier over channels with clipping at the transmitter side is studied. For this, the individual capacities of the OFDM frames are considered. It is shown that capacity is linearly related to the energy of the OFDM frame after clipping. Based on the insight that the power leakage is the main source of the loss, via geometrical considerations a very tight upper bound on the capacity of clipped OFDM is derived. Clipped OFDM performs the same as unclipped OFDM with accordingly reduced signal-to-noise ratio.
Keywords :
OFDM modulation; quadrature amplitude modulation; 4-QAM modulation; OFDM frames; clipped 4-QAM-OFDM; geometrical consideration; power leakage; upper bound; Error analysis; Nonlinear distortion; OFDM modulation; Power system modeling; Quadrature phase shift keying; Signal design; Signal reconstruction; Signal to noise ratio; Transmitters; Upper bound;
Conference_Titel :
Source and Channel Coding (SCC), 2010 International ITG Conference on
Conference_Location :
Siegen
Print_ISBN :
978-1-4244-6872-0
Electronic_ISBN :
978-3-8007-3211-1
