Serviço de referência e informação para smartphones: análise de acesso e uso

Pós-graduação em Ciência da Informação - FFC

Proposta e modelagem de comunicação segura para redes veiculares (VANETS)

Pós-graduação em Ciência da Computação - IBILCE

Sistema de monitoramento de temperatura e umidade em silos graneleiros via rádio

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Simulação e avaliação das tecnologias LTE e DSL como backhaul utilizando software OPNET

A crescente demanda por capacidade vem levando os padrões de comunicação sem-fio a prover suporte para a coexistência de macro e pico células. O backhaul, conexão entre a rede de acesso e o núcleo da rede, é de grande interesse neste contexto devido aos diversos desafios técnicos e financeiros envolvidos ao tentar satisfazer o crescente tráfego dos usuários. Fibra óptica e micro-ondas com linha de visada são as opções mais amplamente adotadas para o backhaul de macro-células. Contudo, em muitas situações de interesse prático, estas não são factíveis devido aos altos custos e logística envolvidos. Este trabalho avalia o backhaul de pico-células, focando primeiramente na utilização de cobre como backhaul. O simulador OPNET foi utilizado para avaliar os requerimentos de backhaul para redes móveis em cenários específicos considerando garantir qualidade de serviço para os diversos tipos de tráfego envolvidos. Assumindo demandas de tráfego para LTE e LTE-Advanced, as tecnologias VDSL2 e G.fast são avaliadas e os resultados mostram que mesmo com uma grande demanda de aplicações de vídeo de alta definição, estas tecnologias podem acomodar o tráfego no backhaul de pico-células. VDSL2 é capaz de prover as taxas requeridas para cenários de pico-células LTE, mas não é capaz de acomodar tráfego LTE-Advanced típico. Por outro lado, considerando as taxas atingidas com a tecnologia G.fast, o tráfego backhaul para pico-células LTE-Advanced pode ainda ser entregue com garantias de qualidade de serviço. Neste trabalho também é proposta uma solução para simulação de cenários contendo redes de acesso heterogêneas considerando backhaul LTE sem linha de visada. São demonstrados também os resultados de simulações no OPNET com o backhaul LTE proposto para validar a solução proposta como capaz de caracterizar o tráfego de ambas as tecnologias WiFi e LTE na rede de acesso de acordo com o tipo de serviço.

Modelagem IEEE 1815 DNP3 em VHDL e análise de comunicação SG via IEEE 802.15.4 e IEEE 802.11

Pós-graduação em Engenharia Elétrica - FEIS

Estudo da tecnologia de acesso Wi-Fie suas aplicações em ambientes indoor e outdoor

Wireless communications is a feature that has become indispensable for many people in the whole world. Through this feature, communication process can become much more efficient, allowing people to access information much more quickly wherever they are. The constant evolution of communication technologies allows the development of new unthinkable applications and services. This new range of possibilities brings greater mobility and efficiency for final users and also helps service providers and carriers to improve the quality of services offered by them. This study presents the principles of wireless communication and the Wi-Fi technology as well as its most modern applications, covering from the basics of computer networks to the procedures of planning a wireless network, concepts of radio frequency, antennas, patterns, regulatory agencies, network equipment, protocols and network monitoring

Implementação e avaliação do protocolo μTESLA: proposta de uso nas redes veiculares

Pós-graduação em Ciência da Computação - IBILCE

Modelo de simulação NS-2 para o protocolo DNP3 sobre o protocolo de rede sem fio IEEE 802.15.4 para simulação de baixo custo de aplicação smart grid

Pós-graduação em Engenharia Elétrica - FEIS

The benefits of soft sensor and multi-rate control for the implementation of wireless networked control systems

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Sistema de monitoramento da temperatura e umidade em silos graneleiros via radiofrequencia

The use of Information and Communication Technology has grown in most agricultural activities. As a consequence, it has changed the way of thinking and acting of the farmer who wants to establish a more and more competitive market. However, the high costs of acquisition and maintenance of those technologies may be a factor which can inhibit its spread and acceptance, mainly to a large number of small grain Brazilian farmers. In this context, there is a need for innovative solutions that are proper for this universe of farmers. Starting from this premise, this paper presents the development of a low cost prototype to the monitoring process of temperature and humidity values of grains stored in silos, using communication based on wireless technology by radio frequency. Therefore, the economic implications of cost/benefit ratio of innovative application of wireless transmission in the process of thermometry of grains were analysed. The prototype was made of two electronic units, one of acquisition and another one of data reception, as well as computational software, which offered the farmer more precise information for the control of aeration. By means of stability, integrity and reliability tests of data transmission via radio, using low cost electronic components, the development system can be considered as potentially viable. It presented the difference regarding the wireless communication via radio in the process of grains thermometry, providing mobility, reducing cabling costs and maintenance, and also offering an easy system expansion; it was also appropriate to temperature and humidity monitoring in grain silos; and revealed operational viability, besides the low cost development when compared to similar products available in the Brazilian market.

Módulo para identificação de objetos e transmissão de dados sem fio

Pós-graduação em Engenharia Elétrica - FEIS

Agent Based Intrusion Detection and Response System for Wireless LANs

Wireless LAN technology, despite the numerous advantages it has over competing technologies, has not seen widespread deployment. A primary reason for markets not adopting this technology is its failure to provide adequate security. Data that is sent over wireless links can be compromised with utmost ease. In this project, we propose a distributed agent based intrusion detection and response system for wireless LANs that can detect unauthorized wireless elements like access points, wireless clients that are in promiscuous mode etc. The system reacts to intrusions by either notifying the concerned personnel, in case of rogue access points and promiscuous nodes, or by blocking unauthorized users from accessing the network resources.

Design of a Wireless Vision Sensor for Object Tracking in Wireless Vision Sensor Networks

The integration of CMOS cameras with embedded processors and wireless communication devices has enabled the development of distributed wireless vision systems. Wireless Vision Sensor Networks (WVSNs), which consist of wirelessly connected embedded systems with vision and sensing capabilities, provide wide variety of application areas that have not been possible to realize with the wall-powered vision systems with wired links or scalar-data based wireless sensor networks. In this paper, the design of a middleware for a wireless vision sensor node is presented for the realization of WVSNs. The implemented wireless vision sensor node is tested through a simple vision application to study and analyze its capabilities, and determine the challenges in distributed vision applications through a wireless network of low-power embedded devices. The results of this paper highlight the practical concerns for the development of efficient image processing and communication solutions for WVSNs and emphasize the need for cross-layer solutions that unify these two so-far-independent research areas.