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In third generation mobile telecommunication systems, signalling requirements due to location updating and paging are expected to be remarkable, mainly because of the huge number of mobile subscribers. Location area planning is characterised by the trade-off between the number of location updates and the amount of paging signalling that the network has to deal with. Location area planning should be based on criteria which guarantee that signalling load will be kept under tolerable levels. Various approaches for location area planning in a city environment—the worst case environment—are discussed in this paper. The simplest approach is the use of heuristic algorithms for approximating the optimum location area configuration. Then more complex scenarios which are based on geographical criteria (population distribution, highway topology, etc.) are investigated. Finally, user mobility characteristics are taken into account in the most complex scenarios. All scenarios are applied over a simulation model representing a city area, providing us with a very clear view of their performance characteristics.This paper has been partially funded by the CEC through the RACE 2066 MObile NETwork (MONET) project. The paper does not present the views of the project as a whole, but those of the authors. 相似文献
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Francis J.C. Polymeros D.V. Lyberopoulos G.L. Keere V. Vande Elberse A. Rogl P. Vezzoli L. 《Mobile Networks and Applications》1998,3(1):61-72
This paper reports on European Commission sponsored research within the EXODUS project. The project carries out research in
the context of the evolution towards UMTS and performs personal and terminal multimedia mobility experiments using fixed and
wide-band radio access in an international ATM network. After introducing the EXODUS platform and services, the paper presents
an IN-based functional model which is suitable for support of mobile multimedia services in ATM networks. Interworking and
mobility management issues are discussed, and information flows for call handling are presented. The paper includes a presentation
of the mobility management and enhanced INAP protocols which have been developed by the EXODUS project.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Mesogiti Ioanna Lyberopoulos George Setaki Fotini Di Giglio Andrea Pelcelsi Alessandro Serra Laura Zou Jim Tzanakaki Anna Anastasopoulos Markos Theodoropoulou Eleni 《Photonic Network Communications》2020,40(3):256-268
Photonic Network Communications - 5G networks will comprise multiple, versatile infrastructures at finest granularity consisting of multiple disaggregated pools of network, compute and storage... 相似文献
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Mitrou N.M. Lyberopoulos G.L. Panagopoulou A.D. 《Vehicular Technology, IEEE Transactions on》1993,42(1):1-13
A multiple-access protocol and a call acceptance algorithm for voice and data integration in a microcellular mobile communication system are presented. The protocol supports circuit-mode voice, burst-mode voice, and data. A hybrid multiplexing scheme with no boundaries performs statistical multiplexing, the call-level (for circuit-mode voice) and the talkspurt/message-level (for burst-mode voice and data). This scheme achieves high utilization of the available bandwidth compared to pure circuit switching, but with a lower quality in the latter two classes, due to delay during channel access on each talkspurt/message. A two-party transaction model for each class is implemented, giving a realistic load on uplink and downlink. A unified access procedure is presented, and the structure of the required control bursts is described. Performance is analyzed using simulation, and the optimum data-segment size is obtained. The maximum acceptable load is determined for various traffic mixes. A call acceptance algorithm is implemented, and typical simulation results for delay and call blocking are given 相似文献
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Korinthios G. Theodoropoulou E. Marouda N. Mesogiti I. Nikolitsa E. Lyberopoulos G. 《Communications Magazine, IEEE》2009,47(9):124-130
There is a continuous pursuit by mobile operators (MOs) to improve indoor coverage in order not only to improve voice quality but also to enable higher data rates in home/office environments. Indoor coverage improvement, in conjunction with inexpensive (voice) offerings, will enable MOs to compete with and take away voice-call-related revenues from fixed network PTTs and/or VoIP operators. Femtocells constitute a promising solution to address all of the above. In this article we present our experience from our extensive study and trials of early (pre-standard) femtocell solutions that were available in the 2007-2008 timeframe. 相似文献
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Lyberopoulos G.L. Markoulidakis J.G. Polymeros D.V. Tsirkas D.F. Sykas E.D. 《Vehicular Technology, IEEE Transactions on》1995,44(3):543-554
Location management procedures, in conjunction with the millions of users expected to subscribe to third generation mobile telecommunication systems, will generate a huge signaling load. In this paper, we propose a method which aims at the reduction of signaling overhead on the radio link produced by the paging procedure. The key idea is the application of a multiple step paging strategy which operates as follows: at the instance of a call terminating to a mobile user who roams within a certain location area, paging is initially performed in a portion of the location area (the paging area) that the so-called “paging related information” indicates. On no paging response, the mobile user is paged in the complementary portion of the location area-this phase can be completed in more than one (paging) step. Various “paging related information” elements (e.g. recent interaction information, high mobility flag, etc.) can be used and several “intelligent” paging strategies can be defined. Representative paging strategies are analyzed in terms of network performance and quality of service (paging signaling, paging delay, processing power requirements), via a simulation tool which models a realistic city area environment 相似文献
7.
C. N. Konstantinopoulou K. A. Koutsopoulos P. P. Demestichas M. E. Theologou G. L. Lyberopoulos 《Wireless Communications and Mobile Computing》2003,3(3):357-384
Data services like Web browsing, e‐mail and file transfer are becoming more and more popular in cellular systems. In contemporary systems like Global System for Mobile communications (GSM), data transfer has been circuit‐switched, that is, physical resources are allocated to a user for the entire call/session duration. However, this is inefficient in case of bursty traffic, where bursts are separated by long intervals of inactivity. This has been the main reason for the introduction of General Packet Radio Service (GPRS), which on the one hand acts as a mobile access network to the Internet, while on the other hand it enables the operator to offer a wide variety of value‐added services [Wireless Access Protocol (WAP) over GPRS, e/m‐banking, e/m‐commerce, push services, etc.] efficiently. However, in contemporary commercial implementations of GPRS the radio resource allocation algorithm does not take into account the Quality of Service (QoS)‐related service characteristics—although such information is exchanged between the terminal and the network—and consequently all service requests are treated the same way (‘best effort’). In this paper, we propose and evaluate via a simulation platform various Radio Resource Management (RRM) schemes capable of differentiating the handling of ‘service requests’ (in uplink and downlink), taking into account the GPRS‐related QoS parameters (precedence, reliability, delay, mean and peak throughput). The evaluation is performed for a range of voice (circuit‐switched) traffic loads, number of Transmit Receive eXchange (TRXs), offered data (packet‐switched) services characteristics, number of dedicated Packet Data Channels (PDCHs), and so on, taking into account the respective QoS requirements for both service types (circuit‐ and packet‐switched). Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Traffic analysis for third generation mobile telecommunication systems should take into account a variety of services (e.g., voice, data, video) and environments (private, public outdoor, public indoor) as well as the user mobility behavior. The analytical traffic model presented in this paper incorporates all the above mentioned features. The model utilizes a set of simplifying assumptions regarding the distribution of certain random time intervals (e.g., call duration and cell residence time) and the handover arrival process. The core of the model focuses on the estimation of the cell border crossing rate and the time it takes a busy mobile user to leave a cell area. This allows for the estimation of the handover rate and the call duration within a cell, which in turn, utilizing an iterative method, allows for the calculation of the offered traffic load per cell. The major advantages of the model are: (a) the simple closed form solutions, (b) its independence from the applied radio resource management scheme, and (c) its accuracy. The latter is validated via a simulation tool, which accommodates different cell-layout scenarios over a geographical area, representing a typical city center, modeled as a Manhattan grid. 相似文献
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