M.Tech. (Electrical Engineering) / For securing food production it is essential that every possible method should be investigated. This study is about utilising low power radio frequency (RF) energy signals from leaky transmission lines for the benefit of plant growth and production in hydroponic systems. Using these lines eliminates common problems like radiation interference and licence application protocols. Plant cell walls are covered with tightly-bonded, positively-charged calcium ions that affect the inflow of nutrients into the cell. As calcium ions have a mass twice that of the potassium ion, the fundamental harmonic of calcium is equal to the first harmonic of potassium (32Hz). Thousands (10k : 1) fewer positive potassium ions also exist around the cell wall and when stimulated at their resonance frequency (16Hz), they will bounce against the tightly bonded calcium ions so these calcium ions become dislodged from the cell wall. If this happens more nutrients can enter the cell causing acceleration in plant growth. A suitable electromagnetic wave for such an action is the amplitude modulated wave especially if it is modulated near the cyclotron resonance frequency of potassium (16Hz) or its even-harmonics of 32,64Hz etc. Applying sufficient energy in the lower modulated frequency when it is the same as the vibration frequency of the potassium ions surrounding the cell wall, these ions will then acquire some energy from the electrical wave. Controlling the process is important because if too many calcium ions are released it would cause plant stress and plant structure breakdown. The amplitude modulated wave will allow sufficient time for the calcium ions to return to the cell wall during the period without energy. To apply radio energy to a plant in the form of amplitude modulated signals requires a medium. One such medium is the use of transmitting energy into two leaky transmission lines to cause worse case standing waves, which could then be absorbed by the plants that are placed in between these transmission lines. The energy from the radio waves is then used to create window periods during which the calcium ions are dislodged allowing additional nutrients to enter the plant cell, enhancing plant growth and production.

M.Ing. / The transmission of digital data at higher data rates and greater reliabilities is becoming increasingly more important in the society of today. The usage of, especially wireless digital data, is increasing at an alarming rate, and the need arises for more bandwidth to be made available for this purpose. Hence, the need arises to optimise and expand the usage of bandwidth currently under use. Existing wireless channels, such as the commercial FM service, need to be re-evaluated and unused bandwidth needs to be developed and used as close to capacity as possible. In this dissertation, a study was launched to develop the FM SST (Supplementary Signal Transmission) commercial analog service as a simplex digital channel that can commercially be used to transmit a myriad of digital data. With the help of a commercial FM radio channel, digital data was transmitted using a number of different modulation schemes to obtain channel measurements for the FM SST channel. The modulation scheme that performed the best, given certain criteria, was GMSK. This raw information was then used to extract first and higher order statistical information from the channel, in order to parameterise discrete channel models, based on a Markov process. The channel models that were used were the Gilbert, GilbertElliott and Fritchman channel models. These channel models were then tested according to their iirst and higher order statistical data to evaluate their effectiveness in modelling the error process on the FM SST channel. It was found that the channel model best approximating the real channels was the Gilbert channel. Once satisfactory results were obtained, these discrete channel models were then used to evaluate various error correction schemes for their ability to correct burst errors on the FM SST channel. From the various schemes evaluated, a (63,39) BCH with an interleaver of index 4 was found to perform the best. The purpose of which is to transmit digital data at the highest data rate possible and at the same time having a bit error rate less than lxl0-6.

Localization and motion control (navigation) are two major tasks for a successful mobile robot navigation. The motion controller determines the appropriate action for the robot’s actuator based on its current state in an operating environment. A robot recognizes its environment through some sensors and executes physical actions through actuation mechanisms. However, sensory information is noisy and hence actions generated based on this information may be non-deterministic. Therefore, a mobile robot provides actions to its actuators with a certain degree of uncertainty. Moreover, when no prior knowledge of the environment is available, the problem becomes even more difficult, as the robot has to build a map of its surroundings as it moves to determine the position. Skilled navigation of a differential drive mobile robot (DDMR) requires solving these tasks in conjunction, since they are inter-dependent. Having resolved these tasks, mobile robots can be employed in many contexts in indoor and outdoor environments such as delivering payloads in a dynamic environment, building safety, security, building measurement, research, and driving on highways. This dissertation exploits the use of the emerging Radio Frequency IDentification (RFID) technology for the design and implementation of cost-effective and modular control techniques for navigating a mobile robot in an indoor environment. A successful realization of this process has been addressed with three separate navigation modules. The first module is devoted to the development of an indoor navigation system with a customized RFID reader. This navigation system is mainly pioneered by mounting a multiple antenna RFID reader on the robot and placing the RFID tags in three dimensional workspace, where the tags’ orthogonal position on the ground define the desired positions that the robot is supposed to reach. The robot generates control actions based on the information provided by the RFID reader for it to navigate those pre-defined points. On the contrary, the second and third navigation modules employ custom-made RFID tags (instead of the RFID reader) which are attached at different locations in the navigation environment (on the ceiling of an indoor office, or on posts, for instance). The robot’s controller generates appropriate control actions for it’s actuators based on the information provided by the RFID tags in order to reach target positions or to track pre-defined trajectory in the environment. All three navigation modules were shown to have the ability to guide a mobile robot in a highly reverberant environment with variant degrees of accuracy.

Debido a la demanda creciente del servicio de telefonía móvil e internet, se requiere que las empresas operadoras instalen más Estaciones Base Celular, lo cual es una oportunidad para Conarca. En ese contexto Conarca tiene como reto enfrentar múltiples proyectos por lo que se plantea realizarlo en base a un enfoque metodológico para la Dirección de Proyectos y ese es el fin de nuestro Trabajo de Investigación, es por ello que, el documento inicia con una breve introducción, seguida por un marco teórico que explica la importancia de la Guía del PMBOK®6ta Edición. A continuación, se incluye un capítulo de caso de negocio, donde se describe a la empresa, se realiza un análisis del entorno, un diagnóstico interno y externo, además del análisis financiero del proyecto con una TIR de 21.32% en nuevos soles, un WACC de 9.636%, con retorno de inversión en 43 meses y una inversión de S/ 517,000. Los siguientes cuatro capítulos corresponden a los Grupos de Proceso de la Guía del PMBOK®6ta Edición: Inicio, Planificación, Ejecución, Monitoreo y Control, finalmente el correspondiente al Cierre, en cada uno de estos capítulos se incluyen formatos que son de gran ayuda para el desarrollo de una adecuada Dirección de Proyectos. Finalmente, se encuentran los capítulos de conclusiones, recomendaciones, anexos, glosario y bibliografía lo cual busca complementar la información de los capítulos anteriores. / Due to the growing demand for mobile phone and internet service, telephone companies are required to install more Cellular Base Stations, which is an opportunity for Conarca. In that context Conarca has the challenge to face multiple projects, for that reason the proposal is to do it based on a methodological approach defined for the Project Management and the reason behind the Thesis, which is why the document begins with a brief introduction, followed by a theoretical framework that explains the importance of the PMBOK®Guide 6th Edition. Then, a business case chapter is included, where the company is described, it is made an analysis of the environment, an internal and external diagnosis is performed and also is made a financial analysis of the project in order to demonstrate its profitability. The following four chapters correspond to the PMBOK®Guide 6th Edition Process Groups: Initiation, Planning, Execution, Monitoring and controlling, finally the one corresponding to the Closure, in each of these chapters, formats that are very helpful for the development of an adequate Project Management are included. Finally, there are the chapters related to conclusions, recommendations, attachments, glossary and bibliography which seeks to complement the information in the previous chapters. / Trabajo de investigación

Using communication signals for radar applications has been a major area of research in radar engineering. In the recent years, due to the widely available wireless signals, a new area of research called commensal radars has emerged. Commensal radars use available wireless Radio Frequency (RF) signals to detect and track targets of interest. This is achieved by placing two antennas, one towards the transmitting base station and the other towards the surveillance area. The signal received by these two antennas are correlated to determine the location and velocity of the target. When a signal passes through a channel, it reflects off the obstacles within its path. These reflections usually degrade quality of the signal and cause interference to the telecommunication systems. To mitigate the effects of the channel on a signal these systems transmit a known bit sequence within each frame. Our goal, with this thesis, is to design and implement a working prototype of a novel architecture for the commensal radar system, which uses these known bit sequences to extract the channel information and determine events of interest. The major novelties of the system are as follows. Firstly, this system will be built upon existing communication systems using Software Defined Radio (SDR) technology. Secondly, this design eliminates the need for a reference antenna, which reduces the cost of the system and creates an opportunity to make the system portable. We name this system Communication-Sensing (CommSense). Since, our plan is to use Global System for Mobile Communication (GSM) as the parent system for the prototype development, we decide to update the name to GSM based Communication-Sensing (GSM-CommSense) system. This thesis begins with theoretical analysis of the feasibility of the GSM-CommSense system. First of all, we perform a link budget analysis to determine the power requirements for the system. Then we calculate the ambiguity function and Cram´er-Rao Lower Bound (CRLB) for a two-path received signal model. With encouraging theoretical results, we design a prototype of the system that can capture real GSM base station broadcast signals. After the design of the GSMCommSense system, we capture channel data from multiple locations with varying environmental conditions. The aim for this set of experiment is to be able to distinguish between different environmental conditions. Then, we performed statistical analysis on the data by means of Probability Density Function (PDF) fitting, a goodness-of-fit test called chi-square test and a clustering algorithm called Principal Components Analysis (PCA). We have presented the results from each analysis and discussed them in detail. Upon, receiving positive results in each step we have decided to move towards using learning algorithms to categorise the data captured by the system. We have compared two widely accepted supervised learning algorithms, called Support Vector Machines (SVM) and Multi-Layer Perceptron (MLP). The results showed that with the current hardware capabilities of the system and the amount of data available per GSM frame, the performance of SVM is better than MLP. Thus, we have used SVM to classify two events of detection and classification across a wall. We have presented our findings and discussed the results in detail. We conclude our current work and provide scope for future work in development and analysis of the GSM-CommSense system.

Wireless networks are an iconic technology of today’s modern era, theyare present in our daily activities as can be exemplified by cellular communications,wi-fi, bluetooth, and others. Vector measurements play an importantrole in the design, simulation, and testing of wireless networks and are usedto characterize key devices operating in the radio interface, such as amplifiers,filters, and mixers.Accurate characterization is the key for improving the capacity and efficiencyof wireless networks. As the demand for network capacity continuouslyincreases, the accuracy of vector measurements must also improve. Further,it is anticipated that such trends will continue in the years to come. Consequently,the wireless industry needs to include nonlinear behavior in theircharacterization and analysis, to assess and guaranty the operation of the devices,and to comply to the specifications from governmental regulations. Incontrast to linear behavior, nonlinear behavior presents an additional bandwidthrequirement because the signal bandwidth grows when it passes throughnonlinear devices. In this thesis, vector measurements for devices operatingin wireless networks are studied, emphasizing a synthetic approach for theinstrumentation. This approach enables the use of digital post-processing algorithms,which enhances the measurement accuracy and/or speed and canovercome hardware impairments. This thesis presents the design of a vectorialmeasurement system for wireless devices considering the aforementionedtrends and requirements. It also explores the advantages of the proposedapproach, describes its limitations, and discusses the digital signal processingalgorithms used to reach its final functionality. Finally, measurement resultsof the proposed setup are presented, analyzed and compared to those of modernindustrial instruments. / <p>QC 20130204</p>

The research presented covers the theory and design of feedback-driven matching networks for radio frequency power amplifiers. The study examines amplifier classifications, types of tunable components, feedback typologies, and control systems to achieve the desired operation. The work centers on designing and implementing a tunable matching network for an amplifier's input and output. The tunable systems provide the amplifier with a wide range of operational frequencies at reasonable power levels comparable to today's modern communication systems and produce millisecond-based tuning times. Simulated results are verified against a fabricated system prototype and tweaked to provide further insight into the design's operation.

The multipactor phenomenon is a major concern in modern satellites that operate with highpower transmission in many frequency bands. It occurs when electrons inside RF componentsare accelerated by the RF fields. These electrons then hit walls inside the device, produc-ing secondary electrons. As the number of electrons increases, it may create noise inside thecomponent, thus deteriorating the original signal-to-noise ratio. When designing radio fre-quency equipment for space applications, it is therefore important to know at which powerlevels this occurs. Multicarrier simulations are time consuming and demand high amounts ofcomputer resources. In this thesis the hybrid L1/L2 method has been tested, which is a methodthat separates the geometric and multicarrier simulations into two parts resulting in a shortercomputation time. The conclusion is that the method is more reliable than single carrier sim-ulations, and that it can be used as a first step in the designing process of RF components.It is also a way of estimating a preliminary threshold before starting a full-scale multicarriersimulation.

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