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Ítem Adaptive planning of 3G/4G systems using Q-analysis or polyhedral dynamics(IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC, 2004-01-01) Cardona, NarcisIn this paper we present a method for use Q-analysis in the initial planning process and later dynamic adaptation for 3G/4G cellular systems that intends to balance load in order to maximize capacity and reduce lost and dropped calls independently of the type of service. We support our proposal on dynamic simulations made with an own developed tool for dynamic simulations of CDMA systems, and show initial results that partially probe our proposed method.Ítem Machine learning classifiers for android malware analysis(Institute of Electrical and Electronics Engineers Inc., 2016-04-27) Cadavid, Andres NavarroAndroid is an operating system which currently has over one billion active users for all their mobile devices, with a market impact that is influencing an increase in the amount of information that can be obtained from different users, facts that have motivated the development of malware by cybercriminals. To solve the problems caused by malware, Android implements a different architecture and security controls, such as unique user ID (UID) for each application, system permissions, and its distribution platform Google Play. It has been shown that there are ways to violate that protection, and how the complexity for create a new solutions are increased while cybercriminals improve their skills to develop malware.Ítem A novel approach to optimal resource allocation in HETnets based on the CINR requested by users(IEEE, 2013-09-08) Pachon De La Cruz, AlvaroThis paper presents an approach for solving the resource allocation problem in heterogeneous networks (HETnets). An optimization model is formulated; its main objective is to achieve the best Quality of Service (QoS) measured by the Carrier to Interference Noise Ratio (CINR). This model is a quadratically constrained optimization problem with continuous and boolean variables. It is solved by an approximation by a sequence of linear optimization problems and a judicious allocation of frequency blocks. It attempts to satisfy the CINR values required by users and demanded by modern standards in data transmission. Theoretically, the model can detect whenever the system cannot fulfill the CINR required, in which case, its solution offers the service provider an allocation of resources that yields a good index of performance. This is reported in numerical simulations that resemble real scenarios of HETnets. The approach configures, in a flexible way, the exploration of the search space, the strategy of frequency block allocation to users, and the solution considered as acceptable by the service provider. © 2013 IEEE.Ítem DVB Coverage Prediction Using Game Engine Based Ray-Tracing Techniques(IEEE, 2011-09-05) Gimenez, Jordi J.This paper presents the results of an evaluation of a propagation model based on ray-tracing techniques using a game engine and Graphics Processing Unit (GPU) in outdoor scenarios, as a gap-filler for a Digital Video Broadcasting Handheld (DVB-H) service. This model involves complete identification of the parameters of wave propagation, multipath components between the transmitter and the receiver as attenuation, time delay of arrival (TDA), full polarimetric transmission matrix, direction of arrival DoA and the direction of departure DoD. In the paper, we present the results of the simulation and compare them with measurements, obtaining a satisfactory fit. © 2011 IEEE.Ítem Technological Models of Municipal Wireless Networks based on Hybrid WiFi/WiMAX Mesh Networks: a proposal to Colombian Municipalities(Ieee, 2009-10-30) Rodríguez Hernández, Pedro SalvadorThe telecommunications infrastructure citizen-oriented has become a necessity in cities that wish to direct themselves to a new Information Society. One of the technological alternatives for these infrastructures is municipal wireless networks. These municipal wireless networks offer flexibility, speed of installation and less implementation costs for cities. For this reason, it is considered of interest the wider use of wireless networks for the Colombian municipalities, considers that in this environment there is limited budget and low rate of connectivity to broadband networks. This article presents a review of the current state of municipal wireless networks related to the technological aspects, with the intention to propose two technological architectures that may be feasible to implement in the Colombian municipalitiesÍtem Applicability of Game Engine for Ray Tracing Techniques in a Complex Urban Environment(IEEE, 2010-09-10) Navarro Cadavid, AndresThis work presents results for a new method of ray tracing in urban environments using game engine and graphic processing unit (GPU). First advantage obtained with this method is the simplicity for 3D modeling from raster digital elevation model (DEM). Second advantage is the ability to precisely obtain ray parameters and the multiple paths interacting between transmitter and receiver in urban environment for high and low base station. A third advantage is the reduction in computing time by using the GPU capacity. In this paper, we show simulation results and compare them with measurements, obtaining a good fit. ©2010 IEEE.Ítem A statistical channel model for on body Area networks in Ultra Wide Band Communications(IEEE, 2009-09-10) Cardona, NarcisThis paper presents a novel statistical channel model for Ultra Wide Band Communications when On Body Area Networks Environments are considered. Results and Analysis of frequency measurements from 1GHz to 12GHz for body area networks are described. We propose a modified Saleh-Valenzuela statistical channel model considering different assumptions for small scale statistics in the model. Results show that the small scale amplitude follows a log normal distribution, the inter arrival times between multi path components are poisson process; the decay factor, the number of paths and clusters follow exponential distributions. The proposed model can be used for realistic simulations for on body communications in Ultra Wide Band systems. © 2009 IEEE.Ítem Performance analysis of scheduling algorithms in Next Generation Networks(IEEE, 2010-09-15) Cuellar Quiñones, Juan CarlosQoS in Convergent networks is widely discussed item in IP networks. But with the implementation of the Next Generation Networks by most operators around the world, QoS for different services and applications must fulfill. In order to deal with this problem, we simulate end to end QoS parameters, according to lTV Y.1540 and Y.1541 recommendations and different scheduling algorithms proposed by manufacturers and the literature. In this paper we show the results for such simulations for voice over IP service in different load conditions.Ítem Digital terrestrial television measurement and coverage models comparison: Evaluation of measurements and simulations on urban enviroment for DVB-T2 signals(IEEE, 2016-06-26) Bernal, Marlon PatinoThis paper presents the measurement process of DVB-T2 signal in an urban environment, and the simulations with a coverage calculation tool able to configure specific details of digital television signals and a detailed cartography. Empirical and simulations results are compared to determine additional settings and correction factors. Additional considerations to support signal planning processes are presented.Ítem Handset based automatic network re-selection system for GSM/GPRS and WiFi(ACM Press, 2008-10-30) Navarro Cadavid, AndrésThis paper presents the results of the development of a handset based automatic network reselection software system, which allows keeping end-to-end connections through semi-transparent handoff on WiFi/GSM-GPRS networks. A description of the developed system's software architecture is given, as well as of the components implemented for it, their functionalities and flow of control, all of which allow the permanent discovery of available networks for the mobile device, their evaluation, selection and switching to the network which offers the best ratings in its performance and operational profile, taking into account the preferences previously configured by the user. The system was developed in Java and C# for different operating systems (WinXP, WinMobile and Linux), and its interoperability has been tested in them. Some of the test scenarios are described and final comments about the tests results are given. Copyright 2008 ACM.