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This paper proposes a learning approach to solve adaptive Connection Admission Control (CAC) schemes in future wireless networks. Real time connections (that require lower delay bounds than non-real-time) are subdivided into hard realtime (requiring constant bandwidth capacity) or adaptive (that have flexible bandwidth requirements). The CAC for such a mix of traffic types is a complex constraint...
A new approach for improving the throughput and reducing the transmit power of OFDMA networks is presented. This combines Co-ordinated Multi-Point (CoMP) with variable cell radiation patterns from semi-smart antennas to optimise the network configuration leading to greater throughput for lower transmission power compared with CoMP on its own.
In a downlink wireless network, the XOR network coding method was used to combine with the Hybrid-ARQ (HARQ) scheme, which can improve the retransmission efficiency of the wireless network. The average number of transmissions and the average packet delay metrics were used to evaluate the performance of the network coding based HARQ (NC-HARQ). The theoretical analysis was given to compare the NC-HARQ...
Power saving is an important issue in wireless networks. This paper proposed an energy-efficient cooperative relay selection scheme that utilized the transmission power more efficiently in cooperative relaying systems. The nodes in the network were deployed with multiple antennas and the decode-and-forward relaying protocol was used. The optimization problem of energy efficiency in cooperative relaying...
This paper propose a novel learning approach that applies NeuroEvolution of Augmenting Topology (NEAT) based learning algorithm to resolve Call Admission Control (CAC) combined with resource allocation in adaptive multimedia wireless networks; this not only decides whether to accept or reject a request call, but also determines the allocated bandwidth to that requesting call. The objective is to maximize...
Early detection and rapid resolution network congestion can considerably improve network capacity. Consequently, much research has been carried out on predicting traffic patterns in 3G networks. This paper introduces a traffic abstraction model to predict the distribution of mobile users and support the congestion control in the semi-smart antenna systems. The simulation result shows that the cumulative...
Radio over Fibre (ROF) is an emerging technique to realize the next generation optical-wireless communication systems, satisfying the increasing need for streaming media and multimedia applications for more and more users. In this paper, an ROF system with bus network topology and carrier frequency of 20 GHz, date rate of 2.5 Gb/s using optical carrier suppression (OCS) technique is modelled and investigated...
The next generation 3GPP long-term evolution (LTE) mobile system will use orthogonal frequency division multiplexing access (OFDMA) as the key technology to improve the spectrum efficiency and flexible user resource allocation. One of the challenges of OFDMA systems is the interference at the cell edge where users are likely to get high interference from neighbouring cells. In a network with non-uniform...
The 3G standard, based on wideband code division multiple access (WCDMA) is now being extended into high-speed downlink access (HSDPA) and high-speed uplink packet access (HSUPA) and further evolved to high-speed packet access (HSPA). The ongoing study of next generation communication proposed by 3GPP is called long term evolution (LTE). The aim of LTE is to provide a peak downlink rate of 100 Mbits/s...
Utility theory based subcarrier allocation algorithms for OFDMA systems are discussed in this paper. Two suboptimal subcarrier allocation algorithms (UPF and NBS) under the utility proportional fairness criterion and Nash bargaining solution criterion are given, which both consider the tradeoff between utility fairness of users and system capacity. Furthermore, compared with rate proportional fairness...
An adaptive resource allocation scheme is proposed for regenerative relay-based orthogonal frequency division multiplexing access systems. This scheme allocates subchannels to guarantee fairness between users, and also saves energy by minimising the transmission power. The subchannel allocation for data rate fairness is considered between direct link users and relay stations in the first time subslot...
P2P worms have posed heavy threat to P2P networks. In this paper, we address the features of reactive worm propagation and further model propagation of reactive worms in applying epidemiology. Based on the analysis of the model presented, we obtain a condition for the global stability of the worm free equilibrium. The model and the condition are validated through large scale simulations, which show...
The power allocation problem with co-channel interference is studied in multi-cell OFDMA cellular relay systems. Based on non-cooperative game theory and using a two-hop data rate balance, a distributed multi-cell power allocation (DMPA) algorithm is proposed, which reduces the transmission power cost and improves the system throughput. The non-cooperative power allocation game model is given in the...
Wireless Mesh Networks based on OFDMA and the Node-Disjoint Multipath Routing Protocol (NDMR) can provide practical high-speed broadband and robust transmission. In this paper, NDMR, a practical protocol in WMN is studied. it reduces routing overhead and achieves multiple node-disjoint routing paths. Also, the OFDMA based WMN and its subcarrier allocation problem is investigated. A novel QoS guaranteed...
In cooperation relay system, two relay stations transmit cooperatively for the relay link users, and the relay link users receive signal by maximal ratio combining. The traditional multiuser scheduling algorithms, Max C/I algorithm for system throughput maximization and proportional fairness (PF) algorithm for user fairness, are extended into the DF cooperative relay systems. The simulation results...
In this paper, the performance of user fairness of resource allocation is considered in the downlink of relay-based OFDMA cellular systems. In the downlink transparent frame structure, the base stations (BSs) transmit in the first time subslot and the relay stations (RSs) transmit in the second time subslot. A non-cooperative power allocation game is defined for maximizing throughput and reducing...
The power allocation problem with co-channel interference is studied in multi-cell OFDMA cellular relay systems. The multi-cell non-cooperative power allocation game model is given in the first time subslot for base stations (BSs) and in the second time subslot for relay stations (RSs) respectively. In all the cells, each transmitter (BS or RS) controls the power allocation on each subchannel to maximize...
A load-based relay selection algorithm that improves the fairness of resource allocation is proposed for relay-based OFDMA systems. This algorithm takes into account the traffic load condition (bandwidth requirement) of relay link users and direct link users. The transmission mode (direct transmission mode or relay transmission mode) of each user will be adjusted based on the user average data rate;...
We analyse different worm and patch propagation models along with the ones we have developed and evaluated as a part of our ongoing passive P2P worm & patch modelling project. This is followed by a brief discussion on worm detection mechanisms proposed by various authors. Towards the very end of this article, we propose a distributed framework for passive worm throttling in P2P networks and discuss...
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