Orientadores: Francisco José Arnold, Leonardo Lorenzo Bravo Roger / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-19T02:17:11Z (GMT). No. of bitstreams: 1 Roccia_ClerivaldoJose_M.pdf: 1742155 bytes, checksum: fd0bcca80aa7a8e8592cfb08b248712e (MD5) Previous issue date: 2011 / Resumo: Redes de Sensores Sem Fio (RSSFs) são utilizadas, normalmente, em ambientes de difícil acesso tais como vulcões, florestas, caldeiras, agricultura de precisão e gasodutos. As unidades fundamentais dessas redes são os nós sensores que trocam informações e dados usando tecnologia sem fio. Como em qualquer tipo de rede de comunicação, podem ocorrer falhas que prejudiquem a operação da RSSF. Por essa razão, é necessário avaliar as métricas de desempenho da rede para que se estabeleçam condições para instalação das mesmas em ambientes específicos. Este trabalho apresenta a avaliação de uma RSSF, baseada na plataforma IRIS, desenvolvida pela Universidade de Berkeley e distribuída comercialmente pela empresa Crossbow Technology Inc, operando no modo de Requisição Resposta (RR) em quatro cenários distintos: campo aberto e cultivos agrícolas de milho, de pinhão e de eucalipto. Esta avaliação tem o objetivo de estabelecer distâncias máximas de separação entre os nós em cada ambiente, mas conservando as condições de operacionalidade da RSSF. O desempenho da rede nestes cenários foi avaliado através das métricas de perda de pacotes, tempo de resposta, consumo de baterias, utilização de largura de banda, consumo de memória e intensidade do sinal de rádio no receptor (RSSI). Nos experimentos foi encontrado que a distância máxima de separação entre os nós na cultura de milho deve ser de 16m, enquanto no pinhão e no eucalipto são de 25,5m e 46m, respectivamente. Os resultados permitem concluir que a densidade da vegetação entre os nós afeta o desempenho das RSSFs / Abstract: Wireless Sensor Networks (WSNs) are used in tough environments such as volcanoes, forests, boilers, agriculture precision and pipelines. The fundamental units of these networks are sensor nodes that exchange information and data using wireless technology. As with any type of network communication, faults can occur that jeopardize the operation of the WSN. For this reason, it is necessary to evaluate the network performance metrics for aiming to establish conditions for network installation in specific environments. This work presents the evaluation of a WSN-based IRIS platform developed by UC Berkeley and distributed commercially by Crossbow Technology Inc. operating in the Request for Response (RR) mode in four different scenarios: an open field and the other scenarios crops of corn, pine nuts and eucalyptus. The network performance in these scenarios was evaluated by metrics such as packet loss, response time, consumption battery, bandwidth, memory consumption and intensity of radio signal receiver (RSSI). In the experiments it was found that the maximum distance separating the nodes in the corn should be 16m, while in pine and eucalyptus were 25,5m and 46m, respectively. The results lead to the conclusion that the density of vegetation between the nodes affects the performance of WSNs / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering at the Cape Peninsula University of Technology, 2012 / This research project addresses the unique challenges of extensive farming in terms of monitoring and controlling remote equipment or events. Poorly maintained roads and escalating fuel costs increase difficulty of farming and the time spent on physically monitoring remote sites further reduces financial yields. The research showed that there are very few solutions that implement wireless or electronic technology to overcome the challenges associated with these isolated and arid areas and that a low-cost, long range wireless telemetry solution that is easy to use would be beneficial for the extensive farming industry. It was therefore the aim of this project to develop a remote monitoring and controlling solution that implements wireless technology to convey information of activities around the farm utilising electronic means. To be able to successfully develop a wireless telemetry solution that will accurately meet the needs of this specific sector of industry, market research was conducted. To guide the research, the QFD (quality function deployment) process for product development has been implemented. The research consisted out of various aspects including a survey, financial considerations and international comparisons. The research also aided in the understanding of the day-to-day activities and also the physical parameters of extensive farms. Also, currently available technologies and products were evaluated to establish whether similarities exist that will aid in the development of a new product. The development process was based on the results obtained in the market research and resulted in a wireless telemetry solution that overcame all the design challenges and proved to be technically feasible, successfully addressing the application requirements. Zigbee technology was utilized for wireless communication because it provided an off-the-shelf solution with a number of readily available development platforms from various technology providers. A communication range of up to 6 kilometres with a transmitted power of 11dBm was achieved for point-to-point communication and a mesh network topology has been implemented for even longer range and complete coverage on farms. Various types of measurements have been catered for, with custom-designed instrumentation which enabled measurements such as water levels, movement and analogue signals. Also, a basic user interface was developed to enable the user to monitor or control the equipment or events remotely from a personal computer, locally or even over the internet. The results of this research project showed that by carefully selecting available technologies and understanding the application, it is possible to develop a solution that addresses the monitoring and controlling needs associated with extensive farming. The wireless telemetry system that was developed resulted in a saving equal to 10% of the total expenses of the farms per year. The telemetry system is therefore a financially feasible solution with a payback period of less than 1 year and far below the initial estimated budget. Without the need to physically monitoring equipment and events, an increase in productivity and the expansion of the overall enterprise is a further benefit added unto the monetary savings. In addition to the financial benefits of implementing new wireless technology, this is an opportunity to contribute to a cleaner and more sustained future as a legacy for the next generation by reducing the carbon footprint of the farm.