The current consumption of the IQ modulator is a significant part of the totalcurrent consumption of a mobile transmitter platform and reducing it is of greatinterest. Also, as the WCDMA/LTE standards specifies full duplex transmissionsand Tx and Rx are most often using the same antenna, it is crucial to have asolution with low noise generation. Two new proposals have been studied with theaim to reduce the current consumption and noise contribution of the IQ modulator. A current mode envelope tracking IQM is the first of the studied designs. Thisimplementation lowers the bias currents in the circuit in relation to the amplitudeof the baseband input signals, meaning that a low input amplitude results in alowering of the current consumption. It proves to be very efficient for basebandsignals with a high peak-to-average ratio. Simulations and calculations have shownthat an average current reduction of 56 % can be achieved for an arbitrary LTEbaseband signal. The second is an entirely new passive mixer design where the baseband voltagesare sequentially copied to the RF node, removing the need for V-to-I conversion inthe mixer which reduces current consumption and noise. Results from simulationshas proven that this design is fully capable of improving both current consumptionas well as the noise levels. With an output power of 4.0 dBm, the power consumptionwas 43.3 mW, including clock generating circuits. This, combined with thefact that the design is small and simple, means that there is definitely a possibilityto replace the present IQM design with a passive mixer.

La prise en charge des auteurs d’infractions à caractère sexuel bouscule les professionnels du soin dans les limites de leurs compétences thérapeutiques et pose par voie de conséquence la récurrente question des chances de réinsertion sociale de ces sujets dans la société.La méconnaissance du fonctionnement intrapsychique de ces patients, l’absence de formation des professionnels à la sexualité normale et pathologique, l’effet de renforcement sur les pulsions partielles produit par internet, ou encore la spécificité du cadre thérapeutique sous contrainte sont autant d’éléments qui nous placent définitivement hors d’un champ habituel de prise en charge en santé mentale. En tentant de prendre en compte l’ensemble de ces spécificités et en explorant de façon standardisée les dimensions psychosociales, psychométriques et psycho-projectives de ces auteurs d’infraction à caractère sexuel, cette recherche vise à mettre en lumière d’une part les variables intrapsychiques qui permettraient d’améliorer les échelles d’évaluation de la dangerosité sexuelle et d’autre part les caractéristiques psychothérapiques susceptibles de répondre aux dysfonctionnements psychiques spécifiques de cette population. / The management of sexual offenders disrupts care professionals within the limits of their therapeutic skills and consequently raises the recurring question of the chances of reintegration in society.The lack of understanding of the intrapsychic functioning of these patients, the lack of training of professionals in normal and pathological sexuality, the reinforcing effect on partial drives produced by the internet, or the specificity of the court-ordered therapy’s framework are all elements which definitely puts us out of the usual mental health care field.By attempting to take into account all these specificities and by exploring in a standardized way the psychosocial, psychometric and psycho-projective dimensions of these sex offenders, this research attempts to highlight on the one hand the intrapsychic variables that would improve scales of sexual dangerosity and secondly the psychotherapeutic characteristics likely to respond to the specific psychological dysfunctions of this population.

Made available in DSpace on 2016-08-19T18:16:04Z (GMT). No. of bitstreams: 1 Dissertacao Michelle.pdf: 1395599 bytes, checksum: cac6fbdd72eabe7033af354481125571 (MD5) Previous issue date: 2012-06-20 / INTRODUCTION. Health professionals are especially concerned with the care of low birth weight children. According to the World Health Organization (WHO) criteria, birth weight below 2500 grams is considered as low. Low birth weight has been found to place the child s future emotional, intellectual, and learning development at risk. Some studies have shown that, on the average, during the preschool phase, premature and low birth weight children evince lower cognitive performance than their normal weight peers. OBJECTIVES. Ascertain the epidemiological and neurological profile of premature, low birth weight children evaluated in a hospital school in Sao Luis, Maranhão. METHODS: A cross-sectional study with a quantitative approach to birth cohort in 2001 of newborns admitted to the Hospital Unit of the Maternal and Child HUUFMA. Researchers recorded 45 records, only 27 of these children participated in the study was conducted using survey data from medical records and was applied to Scale WISC III. RESULTS AND DISCUSSION. Based on findings, although the children sampled were from low-income families, their average total IQ (WISC-III) was in the normal range. Within the children sample there were no significant differences between Verbal and Performance IQ. No significant dependence relationship between epidemiological variables and preterm low birth weight.CONCLUSION: Regardless of birth weight, without severe complications during pregnancy and childbirth, the child can develop their cognitive intellectual, their social and cognitive social skills in a satisfactory and harmonious, (provided that adequately stimulated and under the guidance of skilled professionals), the same way that passes the development of children born at term and normal birth weight. / INTRODUÇÃO: É grande o interesse de profissionais da área da Saúde para com os cuidados com crianças que nascem com baixo peso. Segundo a OMS (Organização Mundial de Saúde), são consideradas de baixo peso, crianças nascidas com peso ≤ 2.500g. As habilidades intelectuais, sociais e emocionais são necessárias para o bom desempenho escolar. Déficits de desenvolvimento se tornam especialmente evidentes quando as crianças atingem a idade pré-escolar, indicando que crianças que foram bebês prematuros de baixo peso ao nascimento têm desempenho escolar significativamente pior em relação a crianças da mesma idade. OBJETIVOS: Determinar o perfil epidemiológico e neuropsicológico de crianças prematuras, com baixo peso, assistidas em um hospital maternidade escola de São Luís, Maranhão. METODOLOGIA: Realizou-se estudo transversal com abordagem quantitativa, com coorte de nascimento no ano de 2001 de recém nascidos internados no Hospital Universitário Unidade Materno-Infantil do HUUFMA. Pesquisou-se 45 prontuários, destas crianças apenas 27 participaram do estudo, realizou-se levantamento de dados através dos prontuários e foi aplicada a Escala WISC III. RESULTADOS E DISCUSSÃO: Na pesquisa realizada os pais das crianças apresentavam nível sócio-econômico baixo, mas as crianças, em sua maioria apresentaram QI Total na categoria média na Escala WISC III; não foi encontrada nenhuma diferença estatística em QI Verbal, QI de execução e QI total dos grupos estudados, nem relação de dependência significativa entre variáveis epidemiológicas e prematuridade com baixo peso. CONCLUSÃO: Independente do peso ao nascer, sem intercorrências graves durante a gravidez e parto, a criança pode desenvolver seu cognitivo intelectual, seu cognitivo social e suas habilidades sociais de forma satisfatória e harmônica, (desde que estimuladas adequadamente e sob orientação de profissionais especializados), da mesma forma que transcorre o desenvolvimento de crianças que nascem a termo e com peso normal ao nascer.

<p>Årligen slutar 30 procent av eleverna gymnasieskolan utan betygsbehörighet. På individuella program (IV) är siffran 85 procent. För att kartlägga skolsituationen för en elevgrupp på IV-programmet intervjuades 24 elever. Utöver detta gjordes en kognitiv bedömning samt en självskattning av upplevd psykisk hälsa. Huvuddelen av eleverna presterade på en ojämn kognitiv nivå, inom normalvariationen. Arton elever bearbetade information långsamt. Eleverna skattade att de mådde psykiskt sämre än normgruppen. De rapporterade tidiga skolsvårigheter som i vissa fall uppmärksammats,men lämnats utan adekvat åtgärd. Elever med långvariga skolproblem,försvårande additiva faktorer kombinerat med ett begåvningsvärde i normalvariationens nedre spann samt långsamhet vid informationsbearbetning upplever negativa individuella konsekvenser. De negativa effekterna kan mildras med tidiga interventioner på en för eleverna adekvat nivå och beaktat elevernas relativa kognitiva styrkor.</p>

<p>In this thesis, a parsimoniously parameterized digital predistorter is derived for linearization of the IQ modulation mismatch and the amplifier imperfection in the signal generator [1]. It is shown that the resulting predistorter is linear in its parameters, and thus they may be estimated by the method of least-squares. Spectrally pure signals are an indispensable requirement when the signal generator is to be used as part of a test bed. Due to the non-linear characteristic of the IQ modulator and power amplifier, distortion will be present at the output of the signal generator. The device under test was the IQ modulation mismatch and power amplifier deficiencies in the signal generator.</p><p>In [2], the dynamic range of low-cost signal generators are improved by employing model based digital pre-distortion and the designed predistorter seems to give some improvement of the dynamic range of the signal generator.</p><p>The goal of this project is to implement and verify the theory parts [1] using data program (Matlab) to improve the dynamic range of the signal generator. The design digital pre-distortion that is implemented in software so that the dynamic range of the signal generator output after predistortion is superior to that of the output prior to it. In this project, we have observed numerical<strong> </strong>problems in the proposed theory and we have found other methods to solve the problem.</p><p>The polynomial model is commonly used in power amplifier modeling and predistorter design. However, the conventional polynomial model exhibits numerical instabilities when higher order terms are included, we have used the conventional and orthogonal polynomial models. The result shows that the orthogonal polynomial model generally yield better power amplifier modeling accuracy as well as predistortion linearization performance then the conventional polynomial model.</p>

Årligen slutar 30 procent av eleverna gymnasieskolan utan betygsbehörighet. På individuella program (IV) är siffran 85 procent. För att kartlägga skolsituationen för en elevgrupp på IV-programmet intervjuades 24 elever. Utöver detta gjordes en kognitiv bedömning samt en självskattning av upplevd psykisk hälsa. Huvuddelen av eleverna presterade på en ojämn kognitiv nivå, inom normalvariationen. Arton elever bearbetade information långsamt. Eleverna skattade att de mådde psykiskt sämre än normgruppen. De rapporterade tidiga skolsvårigheter som i vissa fall uppmärksammats,men lämnats utan adekvat åtgärd. Elever med långvariga skolproblem,försvårande additiva faktorer kombinerat med ett begåvningsvärde i normalvariationens nedre spann samt långsamhet vid informationsbearbetning upplever negativa individuella konsekvenser. De negativa effekterna kan mildras med tidiga interventioner på en för eleverna adekvat nivå och beaktat elevernas relativa kognitiva styrkor.

In this thesis, a parsimoniously parameterized digital predistorter is derived for linearization of the IQ modulation mismatch and the amplifier imperfection in the signal generator [1]. It is shown that the resulting predistorter is linear in its parameters, and thus they may be estimated by the method of least-squares. Spectrally pure signals are an indispensable requirement when the signal generator is to be used as part of a test bed. Due to the non-linear characteristic of the IQ modulator and power amplifier, distortion will be present at the output of the signal generator. The device under test was the IQ modulation mismatch and power amplifier deficiencies in the signal generator. In [2], the dynamic range of low-cost signal generators are improved by employing model based digital pre-distortion and the designed predistorter seems to give some improvement of the dynamic range of the signal generator. The goal of this project is to implement and verify the theory parts [1] using data program (Matlab) to improve the dynamic range of the signal generator. The design digital pre-distortion that is implemented in software so that the dynamic range of the signal generator output after predistortion is superior to that of the output prior to it. In this project, we have observed numerical problems in the proposed theory and we have found other methods to solve the problem. The polynomial model is commonly used in power amplifier modeling and predistorter design. However, the conventional polynomial model exhibits numerical instabilities when higher order terms are included, we have used the conventional and orthogonal polynomial models. The result shows that the orthogonal polynomial model generally yield better power amplifier modeling accuracy as well as predistortion linearization performance then the conventional polynomial model.

Orthogonal frequency division multiplexing (OFDM) systems with cyclic prefix (CP) can be used to protect signal from the time-variant multipath channel induced distortions. However, the presence of CP could greatly decrease the effective data rate, thus many recent research works have been focused on the multiple-input multiple-output (MIMO) OFDM systems without CP (CP-free), equipped with the space-time block codes (ST-BC). The constraint of the conventional MIMO-OFDM (without using the ST-BC) system is that the number of receive-antenna has to be greater than the transmit-antenna. In this thesis, we first consider the ST-BC MIMO-OFDM system and show that the above-mentioned constraint can be removed, such that the condition become that the receive antenna should be greater than one, that is the basic requirement for MIMO system. It is particular useful and confirm to the recently specification, e.g., 3GPP LTE (Long Term Evolution) where the system deploy the 2¡Ñ2 or 4¡Ñ4 antennas systems. This thesis also considers the effects of peak-to-average power ratio (PAPR) in the transmitter and In-phase/ Quadrature-phase (IQ) imbalance in the receiver, and solves them by using the adaptive Volterra predistorter and blind adaptive filtering approach of the nonlinear parameters estimation and compensation, along with the power measurement, respectively. After the compensator of IQ imbalance in the receiver, an equalizer under the framework of generalized sidelobe canceller (GSC) is derived for interference suppression. To further reduce the complexity of receiver implementation, the partially adaptive (PA) scheme is applied by exploiting the structural information of the signal and interference signature matrices. As demonstrated from computer simulation results, the performance of the proposed CP-free ST-BC MIMO-OFDM receiver is very similar to that obtained by the conventional CP-based ST-BC MIMO-OFDM system under either the predistortion or compensation scenario.

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Large close range environmental reflections or poor isolation between the transmit and receive paths of an FMCW radar can overload the receiver. The In phase and Quadrature phase (IQ) Reflected Power Canceller (RPC) provides a solution to the problem by cancelling any close range reflections. In this study a procedure to optimise the design of an RPC is developed and the performance limits of a practical RPC is investigated in depth. There are four focus areas in the evaluation and design of the IQ Reflected Power Canceller. First, an analysis was performed on a theoretical IQ Reflected Power Canceller, which provided insight into how the system functioned and made it possible to identify practical application issues that would arise during the design. The next focus area was the IQ Reflected Power Canceller’s dynamic range. Equations, based on the power and noise characteristics of each component in the canceller, were derived. From these equations, a system, with an optimised dynamic range, could be developed. Next, the IQ Reflected Power Canceller’s feedback loop stability was investigated. The canceller is an active negative feedback control system but, in order to obtain the negative feedback, the feedback signal has to be phase shifted by 180 degrees to the phase of the input signal. An analysis of the canceller’s RF phase contribution resulted in an equation that can be used to manage the nett RF phase in the feedback loop. The evaluation model of the IQ Reflected Power Canceller produced favourable results. The tests performed on the system included measuring the level of cancellation that can be achieved, whether the dynamic range corresponds to the predicted values and the amount of RF phase error that can be introduced in the feedback path while maintaining a stable system. The IQ Reflected Power Canceller was found to perform well in the evaluation. It provided a cancellation of more than 45 dB for close range reflections and the canceller remained stable across a wide range of RF centre frequencies (1 GHz). This means that the FMCW radar’s frequency modulation bandwidth will not be limited because of the IQ Reflected Power Canceller. The evaluation clearly showed that the modulator in the feedback loop is the critical element that determines the dynamic range of the radar with an RPC. / AFRIKAANSE OPSOMMING: Onvoldoende isolasie tussen die sender en ontvanger van ’n Frekwensie Gemoduleerde Kontinu Golf radar, sowel as groot weerkaatsings vanaf voorwerpe in die omgewing van die radar, veroorsaak dat die ontvanger versadig. Hierdie beperking veroorsaak dat die radar ’n verminderde dinamiese bereik het, en daarmee ook dat die radar se maksimum teiken-afstand verminder word. Die IQ Gereflekteerde Drywingskanselleerder kan as ’n oplossing gebruik word teen hierdie ongewenste refleksies. Hierdie navorsing poog om ’n kanselleerder te evalueer met die eind doel gestel daarop om ’n praktiese stelsel aanmekaar te sit. Die kanselleerder word geëvalueer deur na vier fokus areas te kyk. Eerstens word ’n ideale model opgestel, wat ’n beter begrip van die kanselleerder bewerkstellig. Uit hierdie ideale model, is daar praktiese oorwegings wat die kanselleerder affekteer, geïdentifiseer. Ten einde die dinamiese bereik van die radar ontvanger te verbeter, word ’n metode afgelei wat gebruik word om die kanselleerder se dinamiese bereik te optimeer. Hierdie metode neem die maksimum drywingsbeperkinge van die komponente in die kanselleerder in ag. Die kanselleerder is ’n aktiewe terugvoer beheerstelsel, en aangesien ’n sommeerder in die terugvoer lus gebruik word, moet die fase deur die lus met 180 grade geskuif word om sodoende ’n kansellerende sein by die ontvangde sein te tel. Die RF fase foute in die kanselleerder word geanaliseer deur ’n nie-ideale model van die kanselleerder op te stel. Hierdie nie-ideale model maak dit moontlik om die effek van ’n RF fase fout op die kanselleerder se stabiliteit te ondersoek. ’n Praktiese kanselleerder is ontwerp uit die inligting wat versamel is gedurende die evaluasie, en ’n werkende stelsel is aanmekaar gesit. Met hierdie praktiese kanselleerder is die hoeveelheid drywing-onderdrukking wat bereik kan word, gemeet. Die dinamiese bereik van die kanselleerder is ook bepaal en vergelyk met die teoreties berekende waardes. Die aannames oor die effek van die RF fase fout in die kanselleerder, is bevestig deur metings te neem. Goeie resultate is met die kanselleerder behaal. ’n Kansellasie van meer as 45 dB is gemeet vir naby-geleë refleksies. Die kanselleerder het ook stabiel gebly oor ’n wye band van senter-frekwensies (1 GHz). Dus sal die Frekwensie Gemoduleerde Kontinu Golf radar se modulasie bandwydte nie beperk word as gevolg van die kanselleerder nie. Uit die evaluasie is daar gevind dat die modulator die kritieke element in the kanselleerder se terugvoer lus is, dus bepaal die modulator die dinamiese bereik van die radar met ’n kanselleerder.