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Radio resource management for satellite UMTS : dynamic scheduling algorithm for a UMTS-compatible satellite networkXu, Kai January 2009 (has links)
The third generation of mobile communication systems introduce interactive Multicast and Unicast multimedia services at a fast data rate of up to 2 Mbps and is expected to complete the globalization of the mobile telecommunication systems. The implementation of these services on satellite systems, particularly for broadcast and multicast applications to complement terrestrial services is ideal since satellite systems are capable of providing global coverage in areas not served by terrestrial telecommunication services. However, the main bottleneck of such systems is the scarcity of radio resources for supporting multimedia applications which has resulted in the rapid growth in research efforts for deriving efficient radio resource management techniques. This issue is addressed in this thesis, where the main emphasis is to design a dynamic scheduling framework and algorithm that can improve the overall performance of the radio resource management strategy of a UMTS compatible satellite network, taking into account the unique characteristics of wireless channel conditions. This thesis will initially be focused on the design of the network and functional architecture of a UMTS -compatible satellite network. Based on this architecture, an effective scheduling framework is designed, which can provide different types of resource assigning strategies. A functional model of scheduler is defined to describe the behaviours and interactions between different functional entities. An OPNET simulation model with a complete network protocol stack is developed to validate the performance of the scheduling algorithms implemented in the satellite network. Different types of traffic are considered for the OPNET simulation, such as the Poisson Process, ONOFF Source and Self Similar Process, so that the performance of scheduling algorithm can be analyzed for different types of services. A novel scheduling algorithm is proposed to optimise the channel utilisation by considering the characteristics of the wireless channel, which are bursty and location dependent. In order to overcome the channel errors, different code rates are applied for the user under different channel conditions. The proposed scheduling algorithm is designed to give higher priority to users with higher code rate, so that the throughput of network is optimized and at the same time, maintaining the end users' service level agreements. The fairness of the proposed scheduling algorithm is validated using OPNET simulation. The simulation results show that the algorithm can fairly allocate resource to different connections not only among different service classes but also within the same service class depending on their QoS attributes.
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Radio Resource Management for Satellite UMTS. Dynamic scheduling algorithm for a UMTS-compatible satellite network.Xu, Kai J. January 2009 (has links)
The third generation of mobile communication systems introduce
interactive Multicast and Unicast multimedia services at a fast data rate of
up to 2 Mbps and is expected to complete the globalization of the mobile
telecommunication systems. The implementation of these services on
satellite systems, particularly for broadcast and multicast applications to
complement terrestrial services is ideal since satellite systems are capable
of providing global coverage in areas not served by terrestrial
telecommunication services. However, the main bottleneck of such
systems is the scarcity of radio resources for supporting multimedia
applications which has resulted in the rapid growth in research efforts for
deriving efficient radio resource management techniques. This issue is
addressed in this thesis, where the main emphasis is to design a dynamic
scheduling framework and algorithm that can improve the overall
performance of the radio resource management strategy of a UMTS
compatible satellite network, taking into account the unique characteristics
of wireless channel conditions.
This thesis will initially be focused on the design of the network and
functional architecture of a UMTS -compatible satellite network. Based on
this architecture, an effective scheduling framework is designed, which
can provide different types of resource assigning strategies. A functional
model of scheduler is defined to describe the behaviours and interactions
between different functional entities.
An OPNET simulation model with a complete network protocol stack is
developed to validate the performance of the scheduling algorithms
implemented in the satellite network. Different types of traffic are
considered for the OPNET simulation, such as the Poisson Process, ONOFF
Source and Self Similar Process, so that the performance of
scheduling algorithm can be analyzed for different types of services.
A novel scheduling algorithm is proposed to optimise the channel
utilisation by considering the characteristics of the wireless channel, which
are bursty and location dependent. In order to overcome the channel
errors, different code rates are applied for the user under different channel
conditions. The proposed scheduling algorithm is designed to give higher
priority to users with higher code rate, so that the throughput of network is
optimized and at the same time, maintaining the end users¿ service level
agreements. The fairness of the proposed scheduling algorithm is
validated using OPNET simulation. The simulation results show that the
algorithm can fairly allocate resource to different connections not only
among different service classes but also within the same service class
depending on their QoS attributes. / Inmarsat Global Ltd. BGAN and the European Space Agency (ESA)
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