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As scarcity of spectrum resource has become a major bottleneck of the development of next generation radio system, Cognitive radio (CR) arises as a hot research topic in wireless communication. Packet scheduling, one important part of radio resource management, plays a vital role in cognitive radio realization. In this paper, we propose a modified proportional fairness scheduling algorithm with interruption...
EPS (Evolved Packet System) was designed with a new radio access network LTE (Long Term Evolution). But EPS also supports natively non-3GPP accesses with associated QoS (Quality of Service), security and mobility requirements. Although the initial EPS deployment would be with the introduction of LTE for providing higher data rate, operators would still need to introduce non-3GPP accesses, e.g. WiFi,...
In this paper, we develop an analytical framework to determine the capacity of heterogeneous wireless networks with overlapping coverage. The heterogeneous system is modeled as a multi-dimensional Markov chain, in which radio access technology (RAT) selection schemes and different overlapping coverage conditions are embedded. Marked point process theory and concentration and deviation inequality are...
Present 3G Mobile Devices are often supports multiple communication technologies. If software developers want to control the configuration or monitor the characteristics of active Radio Access Technologies (RATs), their mobile applications will have to use different programming interfaces for each technology on various supported platform. We propose Modular Data Link Layer M-DALL for a NEXT GEN Mobile...
This paper proposes efficient analytical models to dimension the required transport bandwidths for the Long Term Evolution (LTE) access network for the elastic Internet traffic (which is carried by the TCP protocol). The dimensioning models are based on the use of Processor Sharing queuing theory to guarantee a desired end-to-end application QoS target. For validating the analytical dimensioning models,...
The objective of this paper is to combine the antenna downtilt selection with the cell size selection in order to reduce the overall radio frequency (RF) transmission power in the homogeneous High-Speed Packet Downlink (HSDPA) cellular radio access network (RAN). The analysis is based on the concept of small cells deployment. The energy consumption ratio (ECR) and the energy reduction gain (ERG) of...
Admission control (AC) is an important feature in a wireless network by which radio resource usage is optimized whilst maintaining the Quality of Service (QoS) of existing users. In this paper, a novel admission control mechanism is proposed for the Long-Term Evolution (LTE) cellular networks. Simulation results show that the proposed AC can provide a more flexible trade-off between network and user...
In the group vertical handover (GVHO) scenario, many mobile terminals (MTs) send handover requests almost at the same time. The traditional vertical handover (VHO) schemes assume that the VHO user is coming one by one, so the current user knows the decision results of previous users, then the optimal result can be obtained. In GVHO scenario, multiple VHO decisions need to be made simultaneously, if...
One of the main features of fourth generation (4G) networks will be heterogeneity in the wireless access environment in which a mobile can connect to multiple radio interfaces simultaneously. Network selection and efficient load balancing among different types of networks will be required to achieve high speed connectivity with seamless mobility. In this paper, we propose a resource allocation mechanism...
Despite recent interests in developing vertical handoff decision algorithms, an essential component of the architecture of the next generation heterogeneous wireless networks, very few studies have so far reported any meaningful comparative performance analysis. This paper attempts to fill this gap in the literature by presenting a comprehensive study on the performance of three vertical handoff decision...
Future wireless access will involve a variety of integrated and interworking technologies. Depending on the conditions (e.g., the specific application, the quality of service requirements, the user mobility) each session will be served through the most suited access network; following some event, there will be a variation of the access technology, which is called vertical handover. Although the use...
In a heterogeneous cellular networks environment, users behaviour and network deployment configuration parameters have an impact on the overall Quality of Service. This paper proposes a new and simple model that, on the one hand, explores the users behaviour impact on the network by having mobility, multi-service usage and traffic generation profiles as inputs, and on the other, enables the network...
In this paper, we apply distributed optimization dynamics of the mutually connected neural networks to RAN selection in heterogeneous type cognitive wireless networks. We evaluate the performance of the proposed approach by implementing it on an experimental heterogeneous wireless network system called Cognitive Wireless Cloud, which supports vertical handover between different radio access networks...
The seamless integration of heterogeneous wireless access networks is currently one of the issues of major interest in the field of telecommunication systems. In an early future technologies like UMTS, WLAN and WiMAX will give broadband access to users that perform their voice/video calls or data sessions without knowledge of the specific technology their terminals are using, following the paradigm...
3GPP has specified that terminals can be configured to use either 2 or 10 ms transmission time interval in high speed uplink packet access systems. The purpose of this paper is to evaluate the benefit of exploiting a mixture of both of the transmissions time intervals within a cell instead of only one. The study is quantified by means of studying the achievable coverage of voice over IP and possible...
Self-organization is a key factor for the future evolution of mobile networks, especially for introduction of the new radio standard LTE. Reasons are the increasing complexity, heterogeneity and management effort. Based on an overview about the current state of the art, the self-organization potential for enabling real plug and play functionality, automatic network optimization, improved end-to-end...
We present a simulation study covering the relation of service dynamics to the transfer and evaluation time of measured system state information in self organizing multi standard joint radio resource management (JRRM) systems. Architectures and algorithms based on network-initiated and mobile-initiated actions are compared. The used hybrid simulation and modeling framework allows for a cost-benefit...
The mobile cellular systems are expected to support multiple services with guaranteed Quality of Service(QoS). But, the ability of wireless systems to accommodate expected growth of traffic load and broadband services is limited by available radio frequency spectrum. Call Admission Control (CAC) is one of the resource management functions, which regulates network access to ensure QoS provisioning...
In 3GPP standard, LTE networks are currently specified by considering Mobile VoIP combined with IMS for session control to ensure voice calls support. So, Mobile VoIP over LTE with IMS can be considered as a target for voice support migration from the current support in Circuit Switched (CS) Domain. Because Mobile VoIP services could potentially be supported over HSPA in the coming years and LTE coverage...
A wide range of emerging real-time services require different levels of Quality of Services (QoS) guarantees over wireless networks. Scheduling algorithms play a key role in meeting these QoS requirements. Most of research in this area have been focused on deterministic delay bounds and the statistical bounds of differentiated real-time services are not well known. This paper provides the mathematical...
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