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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
481

Testing the Validity of the PEAK Relational Training System in Assessing Language & Cognition After Brain Injury

Whiteford, Kristen Maryann 01 August 2014 (has links)
As a field, Behavior Analysis lacks an evidence based solution to assessing and treating language deficits in individuals with brain injuries. Research suggests that using direct instruction with persons with brain injuries is the most effective approach for teaching skills. Research on the PEAK Relational Training System suggests it may be applicable to adults with brain injuries because it does not have an age maximum and it assesses and trains complex language skills. The purpose of the current research is to determine the PEAK Relational Training System's potential applicability in assessing language and cognition functioning in adults with brain injury. 20 adults with brain injuries served as the participants for this study. Using a Pearson Correlation, the relationship between performance on the PEAK assessment and the Ross Information Processing Assessment (RIPA-2), pre-morbid education levels, Glasgow Coma Scale scores, and the location of injury in the brain was analyzed. Significant relationships between PEAK and RIPA-2 scores and PEAK and number of years since injury were shown. Furthermore, implementation of the PEAK was shown to be highly reliable. The current research has shown the effectiveness of the PEAK Relational Training System Direct Training Assessment for adults with brain injury.
482

An Inductor Emulator Approach to Peak Current-mode Control in a 4-Phase Buck Regulator

January 2017 (has links)
abstract: High-efficiency DC-DC converters make up one of the important blocks of state-of-the-art power supplies. The trend toward high level of transistor integration has caused load current demands to grow significantly. Supplying high output current and minimizing output current ripple has been a driving force behind the evolution of Multi-phase topologies. Ability to supply large output current with improved efficiency, reduction in the size of filter components, improved transient response make multi-phase topologies a preferred choice for low voltage-high current applications. Current sensing capability inside a system is much sought after for applications which include Peak-current mode control, Current limiting, Overload protection. Current sensing is extremely important for current sharing in Multi-phase topologies. Existing approaches such as Series resistor, SenseFET, inductor DCR based current sensing are simple but their drawbacks such low efficiency, low accuracy, limited bandwidth demand a novel current sensing scheme. This research presents a systematic design procedure of a 5V - 1.8V, 8A 4-Phase Buck regulator with a novel current sensing scheme based on replication of the inductor current. The proposed solution consists of detailed system modeling in PLECS which includes modification of the peak current mode model to accommodate the new current sensing element, derivation of power-stage and Plant transfer functions, Controller design. The proposed model has been verified through PLECS simulations and compared with a transistor-level implementation of the system. The time-domain parameters such as overshoot and settling-time simulated through transistor-level implementation is in close agreement with the results obtained from the PLECS model. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2017
483

Optimization of energy storage use for solar applications

Ek, Ludvig, Ottosson, Tim January 2018 (has links)
Energy storage systems is very useful to use in solar panel systems to save money, but also tobe more environment-friendly. The project was given by the solar energy companyPerpetuum Automobile (PPAM) and the project is for their customer, the condominiumcompound Ekoxen. The task is to make a energy regulation for Ekoxen's energy storage sothey can save more money. The energy storage primary task is to shave the top-peaks of theconsumption for Ekoxen. Which means that the battery will supply the household instead forthe three-phase grid. This will make the electric bill for Ekoxen cheaper. Thesimulation/analysis of the energy regulation is done in a spreadsheet tool, where one partworks as a Time-of-Use program and the other work as a modbus feature. Time-of-Use is aweb-based program for PV systems with battery storage, where time-periods can be set toaffect the battery behavior. The modbus feature simulates a system where an algorithm can beimplemented. The results will show that the time-periods for charging the battery with theTime-of-Use program needs to be changed two times per year. One time for the summermonths and a second time for the rest of the months. The results will also show that themodbus feature is better on peak shaving than the time-of-use program.
484

Termisk energilagring

Fredriksson, Linda, Johansson, Julia January 2018 (has links)
Sweden is only utilizing half of the available excess heat. To utilize more of the excess heat a seasonal thermal energy storage could be implemented to store excessed heat from the summer when the demand is lower to the winter when the demand is higher. This can be achieved by an integration of a seasonal thermal energy storage to the district heating system. A seasonal thermal energy storage may also reduce the need of the system’s peak load, which often is economically costly and adversely affect the environment. The purpose of the paper is to investigate the possibility for Skövde Värmeverk to implement a seasonal thermal storage. The paper is performed by a literature collection and calculations are made by software programs. The result shows that it is technically possible to implement a pit thermal energy storage and a borhole thermal energy storage, but no outcome shows a profitability within 20 years. A pit thermal energy storage can replace the system’s peak load up to 79 percent and a borhole thermal energy storage up to 2,8 percent. The most suitable case for Skövde Värmeverk is to install a pit thermal energy storage with a storage capacity of 4 GWh.
485

Efeito da temperatura sobre o desempenho e a qualidade dos ovos de codornas japonesas /

Vercese, Francine. 1982- January 2010 (has links)
Resumo: Com o objetivo de avaliar o efeito da temperatura sobre o desempenho e qualidade de ovos de codornas japonesas foi realizado um experimento utilizando-se 480 aves na fase de pós-pico de produção. As aves foram alojadas em uma câmara bioclimática com controle automático de temperatura, contendo duas baterias compostas de cinco andares e dez gaiolas, com capacidade para 24 aves cada gaiola, divididas em dois grupos: 240 aves no grupo controle (21°C) e 240 aves no grupo experimental, com temperaturas contínuas de 24, 27, 30, 33 e 36°C em períodos de 14 dias. O período experimental, com duração de 105 dias, foi dividido em cinco ciclos de 21 dias (um ciclo para cada temperatura), sendo 14 dias na temperatura teste e sete dias na temperatura termoneutra. No final de cada ciclo experimental foi avaliado o desempenho e a qualidade dos ovos. Para todos os tratamentos, as rações foram isonutritivas e isocalóricas. Para a avaliação do desempenho e da qualidade dos ovos utilizou-se um delineamento inteiramente casualisado com dois tratamentos (temperatura termoneutra e temperatura teste) e dez repetições de 24 aves por parcela. A elevação da temperatura piora o consumo de ração, reduz o peso dos ovos, a produção e a massa de ovos. Em temperaturas superiores a 27°C houve piora na qualidade interna e externa dos ovos. / Abstract: In order to evaluate the effect of temperature on performance and egg quality of Japanese quails was conducted an experiment using 480 birds in the post-peak production. The birds were housed in a climate chamber with automatic temperature control, with two batteries composed of five floors and ten cages for up to 24 birds in each cage, divided into two groups: 240 birds in the control group (21oC) and 240 birds in the experimental group, which temperatures of 24, 27, 30, 33 and 36°C. The experiment, lasting 105 days, was divided into five 21-day cycles (one cycle for each temperature), and 14 days at test and seven days a thermoneutral. At the end of each experimental cycle was evaluated performance and egg quality. For all treatments, the diets were isocaloric and isonutritives. For the evaluation of performance and quality of eggs used a completely randomized design with two treatments (temperature and thermoneutral temperature test) and ten replicates of 24 birds per plot. Elevated temperature worsens the feed intake, egg weight, production and egg mass. At temperatures above 27°C worsened the internal and external quality of eggs. / Orientador: Edivaldo Antônio Garcia / Coorientador: Jose Roberto Sartori / Banca: Raphael Lúcio Andreatti Filho / Banca: Antônio Carlos de Laurentiz / Mestre
486

Efeito da discretização espaço-temporal no manejo de águas pluviais

Mahunguana, Manuel José January 2014 (has links)
Os custos econômicos e perdas potenciais de vidas humanas resultantes de falhas em sistemas de drenagem de águas pluviais podem ser enormes, aumentando a necessidade da busca de melhores métodos de dimensionamento destes. Os métodos baseados na precipitação de projeto são os mais usados para a estimativa do hidrograma de projeto em bacias urbanas, devido às facilidades que os mesmos apresentam em relação aos outros métodos. Entretanto, estes métodos têm suas limitações e incertezas, que podem influenciar as características do hidrograma de projeto resultante, incertezas que são, em consequência, transferidas ao dimensionamento hidráulico das obras propostas. No presente trabalho, foram avaliados os efeitos da discretização espacial da bacia, da discretização temporal e da posição do pico do hietograma de projeto, sobre as principais características do hidrograma de projeto. Esses efeitos foram ainda avaliados no dimensionamento hidráulico do sistema de macrodrenagem dos bairros de Mavalane “A” e Maxaquene “A”, localizados na cidade de Maputo em Moçambique. Para avaliar os referidos efeitos, a bacia foi discretizada em 1, 5, 7 e 12 sub-bacias. O intervalo de tempo do hietograma de projeto foi discretizado em 1, 2, 3, 4 e 5 minutos, sendo calculados para cada discretização e intervalo de tempo, hietogramas com pico no início, 25%, 50%, 75% e final do evento com duração correspondente a 90 minutos e 24 horas. Os hietogramas foram transformados em vazão no programa IPHS1, a qual foi propagada no sistema de macrodrenagem usando o modelo EPA SWMM 5.0, sendo obtidos os hidrogramas de projeto resultantes. O exutório da bacia e o trecho C19 localizado na região central da bacia foram escolhidos para análise dos resultados. Os resultados obtidos mostram uma influência importante dos efeitos avaliados nas características do hidrograma de projeto: vazão de pico, tempo de pico e volume parcial e, consequentemente, no dimensionamento da rede de macrodrenagem, sendo o efeito da discretização da bacia o mais influente, seguido dos efeitos da posição do pico da chuva e intervalo de tempo. / The economic costs and potential losses of human lives due to failure in stormwater drainage systems can be significant, calling for an improvement in methods used for its design. The design storm approach, also known as “single-event design-storm” is widespread used in formulating design hydrograph from historical rainfall data in urban watersheds, due to its relative advantages when compared to other methods. Therefore, this approach has its uncertainties which can affect the resulted design hydrograph, and consequently affect the hydraulic design of proposed structures. In this study is presented an assessment of the adopted values in design criteria, during the estimation of design hydrograph used in hydraulic design of stormwater drainage systems. In particular, are assessed the effects of spatial discretization of the watershed, the temporal discretization and peak position of the design hyetograph, in the main features of the resulted design hydrograph. The same effects are then assessed in the hydraulic design of the major stormwater drainage system of Mavalane “A” and Maxaquene “A” neighborhoods, located in Maputo city in Mozambique. To assess these effects, the watershed was discretized into 1, 5, 7 and 12 sub-watersheds. The time step of the design hyetograph was discretized into 1, 2, 3, 4 and 5 minutes, and then computed for each discretization and time step, hyetographs with peak positioned in the beginning, 25%, 50%, 75% and the end of the duration of 90 minutes and 24 hours. The hyetographs were converted into runoff in IPHS1, wish was dynamically routed in the drainage system, using EPA SWMM 5.0. The watershed outlet and conduit C19 were used to analyze the results. The results show an important influence of the assessed effects on the design hydrograph features: hydrograph peak, time to peak and partial volume and, consequently, on the hydraulic design of the major stormwater drainage system, being the effect of spatial discretization of the watershed, the most important, followed by hyetograph peak position and time step.
487

Hydrogeological characterization of watersheds in the semi arid baiano using GIS techniques. / CaracterizaÃÃo hidrogeolÃgica de bacias hidrogrÃficas do semiÃrido baiano atravÃs de tÃcnicas de geoprocessamento

Edivam Josà da Silva 10 February 2009 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / For the adoption of water resources management in dry regions where water availability is limited, knowledge of the different processes of the hydrological cycle is needed, especially the precipitation and flow. Therefore, techniques of GIS are essential in studies of hydrological modeling. The study on maximum flow in a watershed is important because the same act on soil erosion, flooding in urban and rural areas, hydraulic works, among others. The Salitre basin is located in the State of Bahia, Brazil, and its Pacui sub-basin is fully inserted in the Campo Formoso municipio. With a drainage area of 987.74 km2, it is one of the main drainage sub-basin of Salitre river. Hence, the objective of this work was to characterize physiographically the Pacui sub-basin, estimate peak flow by USDA-SCS and Dooge methods, and estimate the hourly evapotranspiration in the sub-basin using the algorithm SEBAL (Surface Energy Balance Algorithms for Land) and images from Landsat 7 - ETM. The Global Mapper software was used for the analysis of land numerical model (SRTM). The ENVI 4.3 software was used for georeferencing of data from topographic maps of SUDENE, and the Arcmap 9.2 software was used for watershed delineation. The time of concentration was determined by USDA and Dooge methods. To determine the radiation balance images from the INPE (National Institute for Space Research) were used and processed by Arcmap  software, within algorithm SEBAL was developed. The basin presented low slope and then tends to reduce the flood peak because of the low speed runoff. ArcHidro proved to be an effective tool in the delineation of river basins and the generation of drainage network and compared with those obtained by maps from SUDENE. The algorithm SEBAL proved to be an agile and efficient tool in evapotranspiration estimation. The use of SRTM provided information of parameters as surface albedo, incident long-wave and shortwave radiations, pixel to pixel. Lower rates of hourly evapotranspiration (<0.15 mm.h-1) were recorded in areas of exposed soils, and higher rates were found in irrigated areas and vegetation, expressing the sensitivity of algorithm SEBAL on evapotranspiration estimation in watershed scale. / Para a adoÃÃo de uma gestÃo adequada dos recursos hÃdricos tendo como unidade de planejamento a bacia hidrogrÃfica, o conhecimento dos diferentes processos do ciclo hidrolÃgico se faz necessÃrio, notadamente da precipitaÃÃo, do escoamento e da evapotranspiraÃÃo. Portanto, tÃcnicas de geoprocessamento sÃo imprescindÃveis nos estudos de modelagem hidrolÃgica a nÃvel de bacias hidrogrÃficas. O estudo sobre o escoamento superficial, em uma bacia hidrogrÃfica à importante pelo fato do mesmo atuar sobre a erosÃo do solo, inundaÃÃes em Ãreas rurais e urbanas, obras hidrÃulicas, entre outros. A bacia do rio Salitre esta localizada no Estado da Bahia, e a sub-bacia do rio Pacui esta inserida totalmente no municÃpio de Campo Formoso, com Ãrea de drenagem de 987,74 km2, constituindo umas das principais subbacias de drenagem para o rio Salitre. Nesse contexto, objetivou-se caracterizar fisiograficamente a sub-bacia rio Pacui e bacia do rio Salitre, analisar a estimativa de vazÃo de pico pelos mÃtodos de SCS-USDA e de Dooge, e estimar a evapotranspiraÃÃo horÃria na bacia do rio Pacui utilizando-se o algoritmo SEBAL (Surface Energy Balance Algorithms for Land) e imagens do Landsat 7 â ETM. Utilizou-se os softwares Global Mapper, para anÃlises do modelo numÃrico do terreno (SRTM), ENVI 4.3, para georeferenciamento dos dados tendo como base as cartas topogrÃficas da SUDENE e do software ArcMap 9.2 para delimitaÃÃo automÃtica de bacias. O tempo de concentraÃÃo foi determinado pelos mÃtodos USDA e de Dooge. Para determinar o balanÃo de radiaÃÃo utilizou-se de imagem da regiÃo obtida junto ao INPE (Instituto Nacional de Pesquisas Espaciais) e processadas na ferramenta Ãlgebra de mapa no software ArcMap onde foi desenvolvido o algoritmo SEBAL. A bacia apresenta baixa declividade, portanto tende a uma reduÃÃo dos picos de descargas devido à baixa velocidade de escoamento superficial. A extensÃo ArcHidro mostrou-se uma ferramenta eficaz na delimitaÃÃo de bacias e na geraÃÃo de rede drenagem, comparando com as obtidas pelas cartas da DSG/SUDENE. O algoritmo SEBAL mostrou-se uma ferramenta Ãgil e eficiente na estimativa da evapotranspiraÃÃo. A utilizaÃÃo do SRTM proporcionou ganhos de informaÃÃes nos parÃmetros albedo da superfÃcie, radiaÃÃo de ondas longas incidente, radiaÃÃo de onda curtas incidente, pixel a pixel. Menores taxas de evapotranspiraÃÃo horÃria (< 0,15 mm.h-1) foram registradas em Ãreas de solos expostos e as maiores nas Ãreas irrigadas e vegetaÃÃo no geral, expressando a sensibilidade do algoritmo SEBAL na estimativa da evapotranspiraÃÃo em escala de bacias hidrogrÃficas.
488

Estudo do efeito de elevação atípica da transcondutância na região linear de polarização em dispositivos SOI nMOSFETS ultra-submicrométricos. / Study of gate induced floating body effect in the linear bias region in deep submicrometer nMOSFETs devices.

Paula Ghedini Der Agopian 27 November 2008 (has links)
Este trabalho apresenta o estudo do efeito de elevação atípica da transcondutância na região linear de polarização devido ao efeito de corpo flutuante induzido pela porta (Gate Induced Floating Body Effect - GIFBE) de transistores da tecnologia SOI nMOSFET. Este estudo foi realizado com base em resultados experimentais e em simulações numéricas, as quais foram essenciais para o entendimento físico deste fenômeno. Além de contribuir com a explicação física deste fenômeno, este trabalho explora o efeito de corpo flutuante em diferentes estruturas (transistor de porta única, transistor de porta gêmea, transistor de múltiplas portas e transistores de canal tensionado), diferentes tecnologias e em função da temperatura (100K a 450K). A partir do estudo realizado em dispositivos SOI de porta única analisouse a influência das componentes da corrente de porta que tunelam através do óxido de porta do dispositivo, o potencial da região neutra do corpo do transistor, a taxa de recombinação de portadores, o impacto da redução da espessura do óxido de porta e também as dimensões físicas do transistor. Na análise feita da redução do comprimento de canal, verificou-se também que o GIFBE tende a ser menos significativo para dispositivos ultra-submicrométricos. Analisou-se também o efeito da elevação atípica da transcondutância para transistores SOI totalmente depletados, para os quais, este efeito ocorre apenas quando a segunda interface está acumulada, para as duas tecnologias estudadas (65nm e 130nm). A análise dos dispositivos de porta gêmea, que tradicionalmente são usados com a finalidade de minimizar o efeito de elevação abrupta de corrente de dreno, mostrou uma redução do GIFBE para este tipo de estrutura quando comparada à de porta única devido ao aumento da resistência série intrínseca à estrutura. O efeito de corpo flutuante também foi avaliado em função da temperatura de operação dos dispositivos. Para temperaturas variando de 100K a 450K, notou-se que o valor do limiar de GIFBE aumentou tanto para temperaturas acima de 300K quanto abaixo da mesma. Quando estes resultados são apresentados graficamente, observa-se que o comportamento do limiar de GIFBE com a temperatura resulta no formato de uma letra C, onde o valor mínimo está a 300K. Este comportamento se deve à competição entre o processo de recombinação e a degradação efetiva da mobilidade. Uma primeira análise do GIFBE em diferentes estruturas de transistores também foi realizada. Apesar dos transistores de canal tensionado apresentarem o efeito para valores menores de tensão de porta, este efeito se manifesta com menor intensidade nestes transistores, devido a alta degradação da mobilidade efetiva apresentada pelo mesmo. Entretanto, quando o foco são os transistores de múltiplas portas, os resultados obtidos demonstram que apesar destes dispositivos terem sido fabricados com dielétrico de porta de alta constante dielétrica, o GIFBE ainda ocorre. Esta ocorrência do GIFBE em FinFETs é fortemente dependente da largura do Fin, da dopagem da região de canal e conseqüentemente do acoplamento das portas laterais com a superior. / This work presents the study of the Gate Induced Floating Body Effect (GIFBE) that occurs in the SOI MOSFET technology. This study has been performed based on experimental results and on numerical simulations, which were an essential auxiliary tool to obtain a physical insight of this effect. Besides the contribution on the physical explanation of this phenomenon, in this work, the floating body effect was evaluated for different structures (single gate and twin-gate transistors), different technologies (130nm and 65nm SOI CMOS technology) and as a function of the temperature (100K to 450K). From the study of the single gate devices, it was evaluated the gate tunneling current influence on GIFBE, the body potential in the neutral region, the recombination rate, the front gate oxide thickness reduction impact, besides the physical dimensions of the transistor. In the performed analysis, taking into account the channel length reduction, it was verified that the GIFBE tends to be less important for ultra-submicron devices. The GIFBE only occurs for fully depleted devices when the second interface is accumulated. In this situation, the floating body effect influence on fully depleted devices was also studied for both technologies (65nm and 130nm). The twin-gate devices analysis, that traditionally are used in order to minimize the Kink effect, show a GIFBE reduction for this structure when it is compared to the single gate one. This enhance in the electrical characteristics is due to the series resistance increase that is intrinsic of this structures. When the temperature variation from 100K to 450K was analyzed, it was obtained the C shape behavior for the floating body effect due to a competition between the recombination process and the effective mobility degradation factor. A first evaluation of the GIFBE occurrence in new devices was also performed. When the focus is the strained silicon transistor, a occurrence of GIFBE was obtained for a lower gate voltage. Although, the GIFBE occurs earlier for strained transistor. This effect is less pronounced in this device because it presents strong effective mobility degradation. When the focus is FinFETs, the results show that although this device was fabricated with a high-k gate dielectric, the GIFBE still occurs and is strongly dependent on the device channel width.
489

Contributions to the Design of RF Power Amplifiers

Acimovic, Igor 19 August 2013 (has links)
In this thesis we introduce a two-way Doherty amplifier architecture with multiple feedbacks for digital predistortion based on impedance-inverting directional coupler (transcoupler). The tunable two-way Doherty amplifier with a tuned circulator-based impedance inverter is presented. Compact N-way Doherty architectures that subsume impedance inverter and offset line functionality into output matching networks are derived. Comprehensive N-way Doherty amplifier design and analysis techniques based on load-pull characterization of active devices and impedance modulation effects are developed. These techniques were then applied to the design of a two-way Doherty amplifier and a three-way Doherty amplifier which were manufactured and their performance measured and compared to the amplifier performance specifications and simulated results.
490

Physical Layer Algorithms for Interference Reduction in OFDM-Based Cognitive Radio Systems

Tom, Anas 01 January 2015 (has links)
Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier transmission scheme used in most of the existing wireless standards such as LTE, WiFi and WiMAX. The popularity of OFDM stems from the multitude of benefits it offers in terms of providing high data rate transmission, robustness against multipath fading and ease of implementation. Additionally, OFDM signals are agile in the sense that any subcarrier can be switched on or off to fit the available transmission bandwidth, which makes it well suited for systems with dynamic spectrum access such as cognitive radio systems. Nonetheless, and despite all the aforementioned advantages, OFDM signals have high spectral sidelobes outside the designated band of transmission, that can create severe interference to users in adjacent transmission bands, particularly when there is no synchronization between users. The focus of this dissertation is to propose baseband solutions at the Physical Layer (PHY) of the communications system to address the interference resulting from the high out-of-band (OOB) emissions of OFDM. In the first part of this dissertation, we propose a precoder capable of generating mask compliant OFDM signals with low OOB emissions that are always contained under a given spectrum emission mask (SEM) specified by the OFDM standard. The proposed precoder generates transmitted signals with bit error rate (BER) performance similar to that of classical OFDM and does not reduce the spectral efficiency of the system. In the second part of this dissertation, we introduce a novel and elegant approach, called suppressing alignment (SA), to jointly reduce the OOB interference and peak-to-average power ratio (PAPR) of OFDM systems. SA exploits the unavoidable redundancy provided by the CP as well as the wireless communications channel to generate an OOB/PAPR suppressing signal at the OFDM transmitter. Furthermore, after passing through the wireless channel, the suppressing signal is aligned with the CP duration at the OFDM receiver, essentially causing no interference to the data portion of the OFDM symbol. The proposed approach improves the PAPR of the transmitted OFDM signal and reduces the OOB interference by tens of decibels. Additionally, the proposed approach maintains an error performance similar to that of plain OFDM without requiring any change in the receiver structure of legacy OFDM. In order to reduce the spectral emissions of OFDM, additional blocks, such as linear precoders, are usually introduced in the transmitter leading to a transmitted signal that is drastically different than that of a classical OFDM signal. This distortion is typically quantified by the error vector magnitude (EVM), a widely used metric specified by the wireless standard and is directly related to the BER performance of the system. The receiver can usually decode the information data with acceptable error probabilities if the distortion introduced to the transmitted signal is below the EVM values specified in the OFDM standard. Linear precoders, while capable of achieving significant reduction in the OOB interference, they typically introduce large distortion to the transmitted signal. As such, the receiver needs to know the precoding done at the transmitter to be able to recover the data which usually entails sending large amount of side information that can greatly reduce the spectral efficiency of the system. In the last part of this dissertation, we target the design of precoders for the purpose reducing the OOB interference, in a transparent manner where the receiver does not need to know the changes introduced in the transmitter. We present two precoders capable of significantly reducing the OOB emissions while producing transmitted signals with EVM values below those specified by the wireless standard, thereby guaranteeing acceptable error performance.

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