Mobile cellular communication systems beyond third generation (3G) are expected to allow subscribers to access an unlimited amount of multimedia and/or voice data with a guaranteed quality of service (QoS) irrespective of their locations. There is therefore a general and continuing requirement to seek improvements to present cellular communication systems for the provisioning of greater throughput per subscriber. In this scope, a further portfolio of standards coined as fourth generation (4G) is currently under study which is intended to extend the capacity of 3G by at least one order of magnitude and offer an entirely packet switched network with data rates expected to range from 100 Mbps for vehicular mobility to lGbps for nomadic access. In order to meet the target of 4G systems, it is clear that the current 3G architecture which is based on a hierarchical cellular structure has to be upgraded. In [1], we introduced a novel relay based architecture termed as Basestation Relay Integration Deployment for "Gth" Enhancement (BRIDGE) as a promising candidate to improve coverage and enhance the capacity of 3G networks at the cell edge. This paper provides an overview of the mathematical analysis of the uplink performance for the integration of this relay based system in the conventional mobile cellular architecture. A comparative study of BRIDGE against the conventional sectorised cell structure for a single cell scenario is provided for performance analysis with respect to coverage, user capacity and transmits power for DS-CDMA system.

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This paper shows the importance of taking into account accurate mobility effects in performance evaluation of key teletraffic metrics of mobile communication networks. To accomplish this task, we introduce a new discrete stochastic node, the Pole of Gravity characterizing the temporal and spatial behavior of mobile users. This novel concept forms the realm of our mobility model termed as Scalable Mobility Model (SMM) and provides a realistic set of Oaths traversed by subscribers on a daily basis by taking into account attraction points, geographical environments, time factor and grouping individual subscribers into specific classes of mobility. Using this Approach, we demonstrate the need and importance of taking mobility-related factors in the analysis of teletraffic issues by investigating the signaling and traffic related parameters such cell residence time and traffic load. Our simulation results include a comparative performance of SMM against the well known random way point model for same performance issues for the City Area of Bristol, UK during the rush and busy hour

In this paper, we present a novel mobility model, called the Scalable Mobility Modeling Tool (SMMT), which is based around a scaleable algorithmic mobility model that can be applied to a large number of possible horizontal environments, from wide area networks (WAN) to local areas networks (LAN), to analyze the issues related to mobility management and radio resource management. The SMMT introduces the new concept of poles of gravity (PG) to characterize the spatial and temporal behavior of mobile users in a scaleable way. This technique has been applied to a cellular communications system superimposed on different geographical frameworks consisting of the City Area Model and City Center of Bristol, UK, to investigate the performance issues related to location and paging area and teletraffic issues respectively. Keywords-Mobility model, location and paging areas, teletraffic models I.INTRODUCTION Mobile services have been experiencing an accelerated penetration which has culminated in the exponential growth of mobile users with outlooks for continued growth in the future. Accordingly, the increase of both mobile related traffic and mobility related signaling load together with the extremely limited number of radio resources and increasing competition in service provision has meant that mobile operators are continuously designing and refining their planning tools to provide optimal and economic network configurations. The aim is not area coverage, but to supply as many mobile users and their traffic demand as possible with a minimum of infrastructure. To allow efficient resource allocation, good models of the underlying movement of mobile users are necessary. As mobile systems develop, the requirements on mobility models become more demanding. As cell sizes decrease, local accuracy becomes more important, but the requirement to model wide scale behavior remains.

In this paper, we present a novel mathematical framework of a mobility model that can be applied to a large number of possible horizontal environments, ranging from local area networks (LANs) to wide area networks (WANs) for the prediction and tracking of mobile users. This new mobility model, termed 'Scalable Mobility Model' (SMM), provides a realistic set of paths for both individual and aggregate subscriber movement by assigning mobile users into specific classes of mobility based on their mobility characteristics, attraction points, geographical environments and time periods. The core technique used to implement these important mobility features in SMM is the introduction of a new concept referred to as the Pole of Gravity. Our mobility model has been decomposed into three processes termed as the physical, gravity and fluid sub-models. Using this new concept, we show how SMM can effectively characterize user mobility for the City Area Model of Avon district and the City Center of Bristol, UK, having an extension of 40 km by 40 km and 8 km by 8 km respectively. We also present simulation results to illustrate the effect of accurate mobility by comparing our realistic mobility model, SMM, with the well know Random Waypoint model. Specifically, we show how the choice of a mobility model affects channel utilization and handover performance issues for the mobile environment.