Title
Throughput analysis of multi-user OFDMA-systems using imperfect CQI feedback and diversity techniques
Abstract
In this paper, the throughput of an adaptive multiuser SISO-OFDMA/FDD system with channel quality information (CQI) signalled digitized over a feedback channel to the transmitter is investigated, where the instantaneous signal-to-noise ratio (SNR) of the different subcarriers is used as CQI to exploit multi-user diversity using adaptive subcarrier allocation. The CQI available at the transmitter is assumed to be imperfect due to estimation errors and quantization at the receiver side, time delay and feedback errors. In this paper, a closed form expression of the average throughput of an adaptive multi-user OFDMA system using imperfect CQI and uncoded M-QAM modulation is derived. Furthermore, a closed form expression of the average throughput of an OFDMA system exploiting frequency diversity, which does not require CQI at the transmitter, is presented. Both throughput performances are compared in order to identify the optimal transmission strategy depending on the grade of CQI imperfectness.
Year
DOI
Venue
2008
10.1109/JSAC.2008.081010
IEEE Journal on Selected Areas in Communications
Keywords
Field
DocType
average throughput,adaptive multi-user ofdma system,multi-user ofdma-systems,throughput performance,diversity technique,imperfect cqi feedback,throughput analysis,fdd system,imperfect cqi,adaptive subcarrier allocation,ofdma system,cqi imperfectness,adaptive multiuser,closed form expression,quadrature amplitude modulation,signal to noise ratio,ofdm modulation,modulation,quantization,feedback,radio transmitters,frequency diversity,probability density function,transmitters,adaptive modulation,throughput,system performance,ofdm
Subcarrier,Link adaptation,Transmitter,Diversity scheme,Quadrature amplitude modulation,Computer science,Real-time computing,Frequency-division multiple access,Throughput,Orthogonal frequency-division multiplexing
Journal
Volume
Issue
ISSN
26
8
0733-8716
Citations 
PageRank 
References 
8
0.69
16
Authors
2
Name
Order
Citations
PageRank
A. Kuhne180.69
Anja Klein217389.48