Title
Scheduling in OFDMA Systems with Outdated Channel Knowledge
Abstract
In wireless systems, most of nowadays scheduler assumes perfect knowledge of the channel quality indicator (CQI) at the transmitter. Unfortunately, this is never the case since the receiver (e.g. mobile users) estimates the CQI at time t-τ and feed back the estimate to the transmitter (e.g. base station). The transmitter uses then this outdated CQI at time t to allocate the radio resources to the users. This paper analyzes this issue at various mobile velocities and proposes improvement of scheduling that reduces the impact of outdated CQI. By using a channel prediction model, we determine the probability distribution function (pdf) of CQI conditioned on the outdated CQIs. We use then this (pdf) in the evaluation of the Block Error Rate (BLER) of the users' transmission and we exploit the result in the development of a novel scheduling rule. Simulation results show improvement of the system performance without any fairness loss.
Year
DOI
Venue
2010
10.1109/ICC.2010.5502497
Communications
Keywords
Field
DocType
error rate,probability distribution function,radio receivers,radio transmitters,scheduling algorithm,system performance,downlink,ofdm modulation,resource management,base stations,probability distribution,wimax,base station,prediction model,resource allocation,statistical distributions,ofdm,scheduling
Base station,Transmitter,Block Error Rate,Computer science,Scheduling (computing),Computer network,Communication channel,Real-time computing,Resource allocation,Orthogonal frequency-division multiplexing,Telecommunications link
Conference
ISSN
ISBN
Citations 
1550-3607
978-1-4244-6402-9
1
PageRank 
References 
Authors
0.37
5
2
Name
Order
Citations
PageRank
Hassan Ayoub110.37
Mohamad Assaad210.70