Final report on the evaluation of RRM/CRRM algorithms

Deliverable public del projecte EVERESTThis deliverable provides a definition and a complete evaluation of the RRM/CRRM algorithms selected in D11 and D15, and evolved and refined on an iterative process. The evaluation will be carried out by means of simulations using the simulators provided at D07, and D14.Preprin

A combinatorial approximation algorithm for CDMA downlink rate allocation

This paper presents a combinatorial algorithm for downlink rate allocation in Code Division Multiple Access (CDMA) mobile networks. By discretizing the coverage area into small segments, the transmit power requirements are characterized via a matrix representation that separates user and system characteristics. We obtain a closed-form analytical expression for the so-called Perron-Frobenius eigenvalue of that matrix, which provides a quick assessment of the feasibility of the power assignment for a given downlink rate allocation. Based on the Perron-Frobenius eigenvalue, we reduce the downlink rate allocation problem to a set of multiple-choice knapsack problems. The solution of these problems provides an approximation of the optimal downlink rate allocation and cell borders for which the system throughput, expressed in terms of utility functions of the users, is maximized

An optimum dynamic priority-based call admission control scheme for universal mobile telecommunications system

The dynamism associated with quality of service (QoS) requirement for traffic emanating from smarter end users devices founded on the internet of things (IoTs) drive, places a huge demand on modern telecommunication infrastructure. Most telecom networks, currently utilize robust call admission control (CAC) policies to ameliorate this challenge. However, the need for smarter CAC has becomes imperative owing to the sensitivity of traffic currently being supported. In this work, we developed a prioritized CAC algorithm for third Generation (3G) wireless cellular network. Based on the dynamic priority CAC (DP-CAC) model, we proposed an optimal dynamic priority CAC (ODP-CAC) scheme for Universal Mobile Telecommunication System (UMTS). We then carried out simulation under heavy traffic load while also exploiting renegotiation among different call traffic classes. Also, we introduced queuing techniques to enhance the new calls success probability while still maintaining a good handoff failure across the network. Results show that ODP-CAC provides an improved performance with regards to the probability of call drop for new calls, network load utilization and grade of service with average percentage value of 15.7%, 5.4% and 0.35% respectively

Scheduling algorithms in broadband wireless networks

Scheduling algorithms that support quality of service (QoS) differentiation and guarantees for wireless data networks are crucial to the development of broadband wireless networks. Wireless communication poses special problems that do not exist in wireline networks, such as time-varying channel capacity and location-dependent errors. Although many mature scheduling algorithms are available for wireline networks, they are not directly applicable in wireless networks because of these special problems. This paper provides a comprehensive and in-depth survey on recent research in wireless scheduling. The problems and difficulties in wireless scheduling are discussed. Various representative algorithms are examined. Their themes of thoughts and pros and cons are compared and analyzed. At the end of the paper, some open questions and future research directions are addressed.published_or_final_versio

Modeling the Effect of Bandwidth Allocation on Network Performance

In this paper, a new channel capacity model for interferencelimited systems was obtained by transforming the Shannon-Hartley theorem for channel capacity. To emulate an operational system, a dashboard Motorola monitoring device was used to collect data from a group of Base Stations (BSs) serving (a section of) the Nigerian air space and belonging to one of the existing network carriers. Our findings revealed that the uplink and downlink throughputs of the existing system were not impressive even when there was uniform sharing of bottlenecks across the BSs. Using MATLAB, simulations were then performed by extending these data, subject to ideal environmental constraints. Results obtained revealed the following: (i) The Shannon-Hartley model performed as expected for no-interference systems (TDMA and FDMA), but as the bandwidth improved, only limited number of users could access the network in the presence of increased SNR; (ii) The proposed model showed improved performance for CDMA networks, but further increase in the bandwidth did not benefit the network; (iii) A reliability measure such as the spectral efficiency is therefore useful to redeem the limitation in (ii).Keywords: Coverage Capacity, CDMA, Mobile Network, Network Throughpu

Study of strategies of selection of the transmission format for the uplink in systems WCDMA

UMTS was born with the objective to improve on the limitations of the second generation mobile, being able to offer multimedia services. It was created to provide multimedia service that requires higher bit rates. UMTS appears because there were new burst‟s services. The physical layer of UMTS is based on the acces technique by WCDMA broadband code division. The WCDMA access networks provide an inherent flexibility in the third generation mobile multimedia services. The radio interface capacity optimization is done with algorithms of Radio Resources, which consider the levels of interference in the system. These algorithms are the congestion control, the admission control, the power control, the suitable transport format management and handover management. In order to be able to understand the Radio Resources Management in UMTS this project has been structured so that in the first chapter it is explained briefly what UMTS is, next, in the second chapter there is an introduction to the WCDMA access technique. In chapter 3 we were centered in the Radio Resources Management, having explained most precise. The next chapter shows the cell coverage study, and the new algorithm implemented in this project. In chapter 5, the system simulator used is explained. And before the conclusions, are the results chapter, explaining the difference of doing the new algorithm or not. Basically, this work consists on the study of the Radio Resources Management and the simulations results with the objective to evaluate the cell coverage study realized in chapter 3. In order to make this task, it had not to consider no type of environmental considerations, because this project is an theoretical work. A possible environmental study in this subject could be given, if the possible electromagnetic waves about the antennas of mobile telephony or the batteries of the terminals, the materials used in the manufacture, etc. will be.The proposed PFC is in the framework of Radio Resources Management and Quality of Service (QoS) for CDMA based radio access networks (such as UMTS). One of the fundamental facts of these systems is to provide different types of multimedia services in order to guarantee certain quality requirements in the connections. The Radio Resources Management strategies (RRM) are in charge of controlling the different radio network parameters so guaranteeing the quality required to the connections and making a use efficient of the resources available. For the case of the uplink, it is very important to determine the format of transmission of the users, i.e., the rate of transmission that the user will have at every moment. The main objective of this PFC is to propose and to evaluate different strategies of user transmision format allocation in order to optimize the trade-off between the delay and the level of interferences that is added to the system. A simulator programed in C is available. This simulator models a real WCDMA system.With this simulator is possible to analyze the power condition, which is important for our study in this project. The study of this algorithm demonstrates how the user bit rate affects in the cell. By controlling the maximum power of each user, we can know if there are cell coverage problems. The analyses show the differences of having droppings or not with the new algorithm and the delay variation

End-to-end admission control of multiclass traffic in WCDMA mobile network and wireline differentiated services

Master'sMASTER OF ENGINEERIN

Call Admission Control in Mobile Wireless

Some problems related to wireless network access are discussed in the article. Special attention is paid to Medium Access Control and Call Admission Control. Both have direct impact on communication link accession. While the first one dictates how to, the second one decides who can access the link. The problems with wireless medium access are mentioned and requirements on MAC protocols are named. Also need for CAC algorithms is illustrated and simple functional example is proposed. Finally, the reasons for future enhancements are shortly discovered