In today's digital world, information and communication technology accounts for 3% and 2% of the global power consumption and CO2 emissions respectively. This alarming figure is on an upward trend, as future telecommunications systems and handsets will become even more power hungry since new services with higher bandwidth requirements emerge as part of the so called ¿future internet¿ paradigm. In addition, the mobile handset industry is tightly coupled to the consumer need for more sophisticated handsets with greater battery lifetime. If we cannot make any significant step to reducing the energy gap between the power hungry requirements of future handsets, and what battery technology can deliver, then market penetration for 4G handsets can be at risk. Therefore, energy conservation must be a design objective at the forefront of any system design from the network layer, to the physical and the microelectronic counterparts. In fact, the energy distribution of a handset device is dominated by the energy consumption of the RF hardware, and in particular the power amplifier design. Power amplifier design is a traditional topic that addresses the design challenge of how to obtain a trade-off between linearity and efficiency in order to avoid the introduction of signal distortion, whilst making best use of the available power resources for amplification. However, the present work goes beyond this by investigating a new line of amplifiers that address the green initiatives, namely green power amplifiers. This research work explores how to use the Doherty technique to promote efficiency enhancement and thus energy saving. Five different topologies of RF power amplifiers have been designed with custom-made signal splitters. The design core of the Doherty technique is based on the combination of a class B, class AB and a class C power amplifier working in synergy; which includes 90-degree 2-way power splitter at the input, quarter wavelength transformer at the output, and a new output power combiner. The frequency range for the amplifiers was designed to operate in the 3.4 - 3.6 GHz frequency band of Europe mobile WiMAX. The experimental results show that 30dBm output power can be achieved with 67% power added efficiency (PAE) for the user terminal, and 45dBm with 66% power added efficiency (PAE) for base stations which marks a 14% and 11% respective improvement over current stateof- the-art, while meeting the power output requirements for mobile WiMAX applications.

ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / A conventionally designed radio frequency amplifier operated in its linear region exhibits low DC to RF conversion efficiency. Typically, for a power amplifier designed for digital modulation applications, the amplifier is operated “backed-off” from its P1dB point by a factor of 10 or -10 dB. The typical linear amplifier is biased for either Class A or Class A/B operation depending on the acceptable design trade-offs between efficiency and linearity between these two methods. A novel design approach to increasing the efficiency of a linear RF power amplifier using a modified Odd-Way Doherty technique is presented in this paper. The design was simulated, built and then tested. The design yields improvements in efficiency and linearity.

In today's digital world, information and communication technology accounts for 3% and 2% of the global power consumption and CO2 emissions respectively. This alarming figure is on an upward trend, as future telecommunications systems and handsets will become even more power hungry since new services with higher bandwidth requirements emerge as part of the so called 'future internet' paradigm. In addition, the mobile handset industry is tightly coupled to the consumer need for more sophisticated handsets with greater battery lifetime. If we cannot make any significant step to reducing the energy gap between the power hungry requirements of future handsets, and what battery technology can deliver, then market penetration for 4G handsets can be at risk. Therefore, energy conservation must be a design objective at the forefront of any system design from the network layer, to the physical and the microelectronic counterparts. In fact, the energy distribution of a handset device is dominated by the energy consumption of the RF hardware, and in particular the power amplifier design. Power amplifier design is a traditional topic that addresses the design challenge of how to obtain a trade-off between linearity and efficiency in order to avoid the introduction of signal distortion, whilst making best use of the available power resources for amplification. However, the present work goes beyond this by investigating a new line of amplifiers that address the green initiatives, namely green power amplifiers. This research work explores how to use the Doherty technique to promote efficiency enhancement and thus energy saving. Five different topologies of RF power amplifiers have been designed with custom-made signal splitters. The design core of the Doherty technique is based on the combination of a class B, class AB and a class C power amplifier working in synergy; which includes 90-degree 2-way power splitter at the input, quarter wavelength transformer at the output, and a new output power combiner. The frequency range for the amplifiers was designed to operate in the 3.4 - 3.6 GHz frequency band of Europe mobile WiMAX. The experimental results show that 30dBm output power can be achieved with 67% power added efficiency (PAE) for the user terminal, and 45dBm with 66% power added efficiency (PAE) for base stations which marks a 14% and 11% respective improvement over current stateof- the-art, while meeting the power output requirements for mobile WiMAX applications.

O exercício da profissão docente requer uma sólida formação, não apenas nos conteúdos científicos da disciplina, mas também nos aspectos correspondentes a sua didática e ao encaminhamento dos diferentes saberes que caracterizam a docência no ensino superior. A formação científica e pedagógica dos professores universitários é um dos fatores básicos na qualidade da universidade, pesquisas apontam que a maioria dos professores possuem lacunas na formação pedagógica. A Universidade de São Paulo USP, lócus desta pesquisa, institui em 1999 o Programa de Aperfeiçoamento de Ensino (PAE) para aprimorar a formação do estudante stricto sensu por meio de duas etapas: Preparação Pedagógica e Estágio Supervisionado em Docência. Dessa maneira o objetivo desse estudo é investigar se o Programa de Aperfeiçoamento de Ensino (PAE) tem-se constituído em espaço formativo para a docência superior a partir da análise das etapas de Preparação Pedagógica e Estágio Supervisionado em Docência. Para tanto, a coleta de dados ocorreu em diferentes momentos. No primeiro momento foram levantados os dados nos Programa de Pós-graduação Stricto Sensu da Faculdade de Educação (humanas), na Escola Politécnica (exatas) e na Escola de Enfermagem (biológicas) do Campus São Paulo Capital, no período de 2001 a 2011. No segundo momento e a partir dos dados coletados, um questionário foi enviado aos pós-graduandos que participaram das duas Etapas do PAE nos Programas investigados. De natureza qualitativa, o procedimento metodológico adotado foi o Estudo de Caso Único Integrado, seguidas da análise documental e análise de conteúdo. As análises apontaram que grande parte dos pós-graduandos, participantes do Programa PAE reconhecem: a ausência da formação pedagógica do professor universitário nos programas de pós-graduação stricto sensu, e identificam contribuições do PAE para o exercício da docência em ambas as etapas (Preparação Pedagógica e Estágio Supervisionado em Docência) possibilitando o aprimoramento e aprofundamento profissional. Com relação à Etapa de Preparação Pedagógica os dados revelam que o conjunto de conferências é a atividade mais procurada pelos alunos, seguida das disciplinas e do núcleo de atividades. Embora mais procurada, percebem o conjunto de conferências como uma proposta pouco efetiva para a formação docente. Quanto à Etapa do Estágio Supervisionado em Docência, os participantes, destacam ser este o verdadeiro momento de formação pedagógica, por proporcionar a reflexão sobre os saberes do campo pedagógico de maneira sistemática, organizada, os aproximando da realidade da sala de aula na graduação. Por fim, a conclusão deste estudo revela que o PAE representa na Universidade de São Paulo, um espaço de formação para a docência, entretanto, não explora todo seu potencial formativo. Ressaltamos a necessidade de sanar as ações isoladas que fragmentam e fragilizam a formação pedagógica do pós-graduando e, ainda, destacamos a urgência da criação de políticas institucionais e diretrizes específicas que tratem dessa formação no Programa PAE e consequentemente nos programas de pós-graduação da Universidade de São Paulo. / The professor professional practice requires a solid education, not only in the scientific discipline content but also in the aspects corresponding to its didactic and in the leading of different knowledge which characterizes teaching in higher education. The scientific and pedagogic education of university professors is one of the ground factors in the quality of the university; researches show that the majority of the professors show gaps in their pedagogic education. The University of São Paulo USP, lócus of this research, established in 1999 the Improvement Teaching Program (ITP) to perfect strictosensustudents education in two stages: Pedagogic Preparation and Supervised Internship in Teaching. As a result, the aim of this study is to investigate whether the Improvement Teaching Program (ITP) has been an educational environment to higher education professors considering the analysis of different stages (Pedagogic Preparation and Supervised Internship in Teaching). In order to do that,data collection occurred in two different instances. In a first instance, data collection was made from 2001 to 2011 in Education College StrictoSensuPost-Graduation Program (Humanities), Polytechnic School (Exact science) and Nursing School (Biological science), São Paulo campus capital. In a second instance, a questionnaire was sent to the students who participated in ITP in the above mentioned teaching unities. Concerning qualitative nature, the adopted methodological procedure was Case Study followed by the documental and content analysis.Analysis show that the great part of post-graduating, taking part in ITP Program acknowledge the lack of pedagogic education of university professor in strictosensupost-graduation programs and identified contributions of ITP for higher education practice in both stages (Pedagogic Preparation and Supervised Internship in Teaching), allowing the professional deepening and improvement. Concerning the Pedagogic Preparation, data reveals that the conference group is the activity which interested students the most, followed by the disciplines and by the activity nucleus. Although it was the one that interested students the most, they realize the conference group as a fairly effective proposal to teaching education. Regarding to Supervised Internship in Teaching, the participants highlighted it as the actual moment of pedagogic education as it provides reflection on the pedagogic field knowledge in a systematic and organized way approaching them to the reality of a classroom in graduation. All in all, the conclusion of this study reveals that ITP represents at University of São Paulo a higher education environment, however, it does not explore its formative potential. It is worth pointing out the need to resolve isolated actions that fragment and undermine the post-graduation pedagogic education, and the urgency of the creation of institutional and specific policies which addresses to this education at ITP Program and consequently in post-graduation programs of University of São Paulo.

Submitted by Irvana Coutinho (irvana@ufpa.br) on 2013-10-07T11:07:29Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SociedadesEconomiaNatural.pdf: 5455158 bytes, checksum: d6a7bae729e4cb86059bdd8f5932462c (MD5) / Approved for entry into archive by Irvana Coutinho(irvana@ufpa.br) on 2013-10-07T11:10:18Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SociedadesEconomiaNatural.pdf: 5455158 bytes, checksum: d6a7bae729e4cb86059bdd8f5932462c (MD5) / Made available in DSpace on 2013-10-07T11:10:18Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_SociedadesEconomiaNatural.pdf: 5455158 bytes, checksum: d6a7bae729e4cb86059bdd8f5932462c (MD5) Previous issue date: 2012 / Este trabalho objetiva analisar de forma crítica a noção de comunidades tradicionais da região de Juriti Velho, Juruti, no âmbito de Projeto Agroextrativista (PAE) conduzido pela Superintendência Regional do Instituto Nacional de Colonização e Reforma Agrária (INCRA), em Santarém apresentando como marco teórico a definição de sociedade de economia natural e superpopulação relativa. Para a elaboração desta pesquisa utilizou-se entrevistas, análises documentais e bibliográficas. Concluiu-se que estas comunidades atingidas pelo projeto são, em muitos casos, expulsos de seu território e migram para as cidades em busca de melhores condições e trabalho contribuindo para o aumento do exército de reserva do capital e para a dissolução de seu aspecto tradicional. / This paper aims to examine critically the notion of traditional communities in the region of Old Juruti, Juruti under Project Settlement Project (PAE) conducted by the Regional Superintendent of the National Institute of Colonization and Agrarian Reform (INCRA) in Santarém. presenting as a theoretical definition of natural economy and society of relative surplus population. For the preparation of this research used interviews, analysis, documentation and bibliography. It was concluded that these communities affected by the project are in many cases, expelled from its territory and migrate to cities in search of better working conditions and contributing to the increase of the reserve army of capital and the dissolution of its traditional appearance.

Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2017-02-20T15:56:28Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_ImpactoCriacaoProjeto.pdf: 2495368 bytes, checksum: 361777ffe1a268534ebc302315edd6da (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-03-02T16:27:37Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_ImpactoCriacaoProjeto.pdf: 2495368 bytes, checksum: 361777ffe1a268534ebc302315edd6da (MD5) / Made available in DSpace on 2017-03-02T16:27:37Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_ImpactoCriacaoProjeto.pdf: 2495368 bytes, checksum: 361777ffe1a268534ebc302315edd6da (MD5) Previous issue date: 2014-10-03 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / FAPESPA - Fundação Amazônia de Amparo a Estudos e Pesquisas / IDRC - International Development Research Centre / A região do baixo amazonas ocupa cerca de 800.000 km² da zona úmida da bacia amazônica e a várzea do rio amazonas com seus maiores afluentes representa aproximadamente 40% desse total. Várzea é um ambiente rico, com solos férteis, que mantém abundantes recursos naturais. Ao longo da história da ocupação humana, a várzea desempenhou um papel central na economia da região Amazônica. Apesar da importância da região, a posse de terras de várzea sempre foi ambígua. Desde 2006, o governo criou 15 Projetos de Assentamento Agroextrativista (PAE) na região de várzea do Baixo Amazonas para regular a posse da terra e para incentivar o processo de participação comunitária na gestão dos recursos naturais. O objetivo principal deste trabalho é analisar o impacto trazido pela criação do PAE no ordenamento territorial e na gestão de recursos naturais da várzea. Os dados deste trabalho foram obtidos por meio de observação participante no campo, revisão da literatura, grupos focais e entrevistas com representantes das comunidades, entidades e órgãos responsáveis pela implementação dos PAEs. A área de estudo situa-se em dois Projetos de Assentamento Agroextrativistas da várzea do Baixo Amazonas nos Municípios de Santarém e Alenquer. 86% das comunidades dos PAEs analisadas tinham algum tipo de acordo de pesca comunitário que internamente regula o uso dos recursos de pesca nos lagos das comunidades. Das entrevistas com os líderes comunitários na região, 82% demonstrou insatisfação com o processo da implementação do PAE na região. Em relação ao Plano de Utilidade (PU), que define as normas do PAE, 33% consideram que as normas dificultam o desenvolvimento na várzea. Mas 77% dos entrevistados acreditam que o PU é necessário para o bom funcionamento do assentamento. Os maiores entraves à implementação do PAE apontados pelo estudo incluem a falta de diálogo entre a comunidade e as entidades governamentais como o INCRA - responsável pela implantação do PAE, a não entrega dos títulos de terra e a falta de definição em relação à ocupação da terra pelos criadores de gado na região. O processo de implementação dos PAEs enfraqueceu a autonomia organizacional das comunidades na gestão dos recursos naturais e não resolveu os problemas relacionados a regulamentação das terras de várzea. / Wetlands in the lower Amazon basin occupy approximately 800.000 km2, and the floodplains of the Amazon River and its larger tributaries represent approximately 40% of this total. Floodplain is a rich environment with fertile soils and abundant natural resources. Throughout the history of human occupation, the floodplain played a central role in the economy of the Amazon region. Despite the importance of the region, land ownership was always ambiguous in these areas. Since 2006, the Government created 15 Projects of Agro-extractive Settlement Project (PAE) in the region of the lower Amazon floodplain in order to regulate land ownership and to encourage the process of community participation in the management of natural resources. The main objective of this study is to analyse the impact brought by the creation of PAE in regional planning and governance of natural resources in the floodplain. The research data collection was through participant observation method in the field, literature review, focus groups and interviews with representatives of the communities, institutions and government bodies responsible for implementing of the PAEs. The study area is located in two Settlement Projects of the lower Amazon floodplain in the municipalities of Santarém and Alenquer. 86% of the communities of PAEs analysed had some sort of Community fishing agreement, which internally governed the use of fishery resources in lakes communities. Interviews with community leaders in the region, 82% showed dissatisfaction with the process of the implementation of PAE. Relative to the Utility Plan (PU), which defines the regulations of the PAE, 33% consider that the rules hinder the development of floodplains. However, 77% of respondents believe that the PU is necessary for the proper functioning of the settlement. The research pointed out that the major difficulties for the implementation of the Project include the lack of dialogue between the community and governmental entities as the INCRA - responsible for the implementation of PAE, the non-delivery of land titles and the lack of definition regarding the ranchers who occupy land in the region. The study also pointed out that the implementation process of the PAEs, besides not solving problems related to land occupation, weakened the organizational autonomy of communities in natural resource management of floodplains.

<p>The purpose of this master thesis was to study if the drain efficiency of power amplifiers can be maintained at power back off using a technique called load modulation.</p><p>The amplifier classes studied are E, F and D-1. The target figure was to obtain a 10 to 12 dB dynamic range of amplitude with reasonable efficiency. Studies of power amplifiers have been made to understand how power is generated. Several different load modulation networks have been evaluated. Attempts to derive design equations for the modulation networks have also been done.</p><p>The thesis work was carried out with simulations in ADS 2006. As active devices commercially available bare-die transistor models have been used. The power rating of the dies are 15 W.</p><p>A dynamic range of amplitude of over 15 dB has been achieved with drain efficiency greater than 60 percent. The peak output power is in the 40 – 45 dBm range.</p>

The purpose of this master thesis was to study if the drain efficiency of power amplifiers can be maintained at power back off using a technique called load modulation. The amplifier classes studied are E, F and D-1. The target figure was to obtain a 10 to 12 dB dynamic range of amplitude with reasonable efficiency. Studies of power amplifiers have been made to understand how power is generated. Several different load modulation networks have been evaluated. Attempts to derive design equations for the modulation networks have also been done. The thesis work was carried out with simulations in ADS 2006. As active devices commercially available bare-die transistor models have been used. The power rating of the dies are 15 W. A dynamic range of amplitude of over 15 dB has been achieved with drain efficiency greater than 60 percent. The peak output power is in the 40 – 45 dBm range.

O exercício da profissão docente requer uma sólida formação, não apenas nos conteúdos científicos da disciplina, mas também nos aspectos correspondentes a sua didática e ao encaminhamento dos diferentes saberes que caracterizam a docência no ensino superior. A formação científica e pedagógica dos professores universitários é um dos fatores básicos na qualidade da universidade, pesquisas apontam que a maioria dos professores possuem lacunas na formação pedagógica. A Universidade de São Paulo USP, lócus desta pesquisa, institui em 1999 o Programa de Aperfeiçoamento de Ensino (PAE) para aprimorar a formação do estudante stricto sensu por meio de duas etapas: Preparação Pedagógica e Estágio Supervisionado em Docência. Dessa maneira o objetivo desse estudo é investigar se o Programa de Aperfeiçoamento de Ensino (PAE) tem-se constituído em espaço formativo para a docência superior a partir da análise das etapas de Preparação Pedagógica e Estágio Supervisionado em Docência. Para tanto, a coleta de dados ocorreu em diferentes momentos. No primeiro momento foram levantados os dados nos Programa de Pós-graduação Stricto Sensu da Faculdade de Educação (humanas), na Escola Politécnica (exatas) e na Escola de Enfermagem (biológicas) do Campus São Paulo Capital, no período de 2001 a 2011. No segundo momento e a partir dos dados coletados, um questionário foi enviado aos pós-graduandos que participaram das duas Etapas do PAE nos Programas investigados. De natureza qualitativa, o procedimento metodológico adotado foi o Estudo de Caso Único Integrado, seguidas da análise documental e análise de conteúdo. As análises apontaram que grande parte dos pós-graduandos, participantes do Programa PAE reconhecem: a ausência da formação pedagógica do professor universitário nos programas de pós-graduação stricto sensu, e identificam contribuições do PAE para o exercício da docência em ambas as etapas (Preparação Pedagógica e Estágio Supervisionado em Docência) possibilitando o aprimoramento e aprofundamento profissional. Com relação à Etapa de Preparação Pedagógica os dados revelam que o conjunto de conferências é a atividade mais procurada pelos alunos, seguida das disciplinas e do núcleo de atividades. Embora mais procurada, percebem o conjunto de conferências como uma proposta pouco efetiva para a formação docente. Quanto à Etapa do Estágio Supervisionado em Docência, os participantes, destacam ser este o verdadeiro momento de formação pedagógica, por proporcionar a reflexão sobre os saberes do campo pedagógico de maneira sistemática, organizada, os aproximando da realidade da sala de aula na graduação. Por fim, a conclusão deste estudo revela que o PAE representa na Universidade de São Paulo, um espaço de formação para a docência, entretanto, não explora todo seu potencial formativo. Ressaltamos a necessidade de sanar as ações isoladas que fragmentam e fragilizam a formação pedagógica do pós-graduando e, ainda, destacamos a urgência da criação de políticas institucionais e diretrizes específicas que tratem dessa formação no Programa PAE e consequentemente nos programas de pós-graduação da Universidade de São Paulo. / The professor professional practice requires a solid education, not only in the scientific discipline content but also in the aspects corresponding to its didactic and in the leading of different knowledge which characterizes teaching in higher education. The scientific and pedagogic education of university professors is one of the ground factors in the quality of the university; researches show that the majority of the professors show gaps in their pedagogic education. The University of São Paulo USP, lócus of this research, established in 1999 the Improvement Teaching Program (ITP) to perfect strictosensustudents education in two stages: Pedagogic Preparation and Supervised Internship in Teaching. As a result, the aim of this study is to investigate whether the Improvement Teaching Program (ITP) has been an educational environment to higher education professors considering the analysis of different stages (Pedagogic Preparation and Supervised Internship in Teaching). In order to do that,data collection occurred in two different instances. In a first instance, data collection was made from 2001 to 2011 in Education College StrictoSensuPost-Graduation Program (Humanities), Polytechnic School (Exact science) and Nursing School (Biological science), São Paulo campus capital. In a second instance, a questionnaire was sent to the students who participated in ITP in the above mentioned teaching unities. Concerning qualitative nature, the adopted methodological procedure was Case Study followed by the documental and content analysis.Analysis show that the great part of post-graduating, taking part in ITP Program acknowledge the lack of pedagogic education of university professor in strictosensupost-graduation programs and identified contributions of ITP for higher education practice in both stages (Pedagogic Preparation and Supervised Internship in Teaching), allowing the professional deepening and improvement. Concerning the Pedagogic Preparation, data reveals that the conference group is the activity which interested students the most, followed by the disciplines and by the activity nucleus. Although it was the one that interested students the most, they realize the conference group as a fairly effective proposal to teaching education. Regarding to Supervised Internship in Teaching, the participants highlighted it as the actual moment of pedagogic education as it provides reflection on the pedagogic field knowledge in a systematic and organized way approaching them to the reality of a classroom in graduation. All in all, the conclusion of this study reveals that ITP represents at University of São Paulo a higher education environment, however, it does not explore its formative potential. It is worth pointing out the need to resolve isolated actions that fragment and undermine the post-graduation pedagogic education, and the urgency of the creation of institutional and specific policies which addresses to this education at ITP Program and consequently in post-graduation programs of University of São Paulo.

Les systèmes de transmission de l’information sans fil connaissent un essor considérable et sont intégrés dans la plupart des systèmes électroniques modernes. De manière plus spécifique, la consommation énergétique de la fonction amplification de puissance RF, qui constitue le cœur de ce travail de recherche, est un enjeu économique et écologique de premier plan. Dans ce sens, ce travail présente une architecture de polarisation de drain dynamique permettant de maintenir un rendement énergétique élevé sur une large dynamique de puissance de sortie. La conception et la réalisation d’un amplificateur de puissance RF large bande, d’un modulateur de polarisation de drain haute fréquence et d’un pilote de grille en technologie GaN sont présentés. L’architecture proposée démontre une amélioration du rendement énergétique global. Une focalisation sur la problématique de couplage non-linéaire entre l’amplificateur de puissance RF et le module d’alimentation agile met en évidence les répercussions de cette méthode sur l’intégrité du signal. Une étroite impulsion de polarisation de grille est appliquée afin d'atténuer l’impact de la polarisation dynamique de drain sur les formes d'onde de l'enveloppe du signal RF amplifié. Une validation expérimentale du démonstrateur proposée est effectuée pour un signal impulsionnel RF multi-niveaux de test. Cette méthode permet de maintenir un facteur de forme de l’enveloppe du signal de sortie RF quasi-rectangulaire sans impact majeur sur les performances globales énergétiques. / Wireless communications are experiencing tremendous growth and are integrated into most modern electronic systems. More precisely, saving energy consumption of RF power amplifier is the core of this thesis work. This work presents a dynamic drain bias architecture used to keep a high efficiency over a large output power range. Design and implementation of a wideband RF power amplifier, a drain supply modulator and a gate driver circuit in GaN technology are presented. The built-in prototype demonstrates an overall efficiency improvement. A specific focus on non-linear interaction between the RF power amplifier and the drain supply modulator highlights the effects of this technique on the output envelope signal shape. A narrow pulse gate bias peaking preceding drain bias voltage variations is applied in order to mitigate drain bias current, voltage overshoot and power droop, thus improving pulse envelope waveforms of the RF output signal. An experimental validation of the proposed demonstrator is performed for a RF pulsed test sequence having different power levels. This way enables to keep rectangular pulse envelope shape at the RF output signal without any major impact on overall efficiency performances.