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This study examines the birth of television and the modern media corporation that launched it, through the archives of the designer of the "first" set, John Vassos, a Greek-born American industrial designer, interior decorator, and illustrator (1898-1985). Vassos's early career is used as a case study to analyze the historical and cultural forces that shaped the emergence of this new media and the new profession of industrial design, through archival materials housed in the Archives of American Art at the Smithsonian Institution in Washington D.C. and at Syracuse University. Specifically, this thesis unites various parts of Vassos's early career, from his modernist illustrations to industrial design, through the aesthetics and practices of modernism. As RCA's lead industrial designer for over 40 years, Vassos was involved in the design and promotion of RCA's electronic products, including radios and televisions and studio equipment. Vassos also designed the new spaces carved out for their use in the home including the "living room of the future" featured at the 1939 World's Fair. Drawing from his skills as an illustrator, designer and display expert, Vassos helped develop RCA's public image at a time of its greatest expansion in radio and television manufacturing and broadcasting. This reading of Vassos's work is both diachronic, taking into account his work over the early part of his career to analyze his specific contribution and synchronic, in relationship to other designers working contemporaneously. Thus, this thesis explores Vassos's double role as a participant, with active agency within the emergence of the new field and as a subject, constrained by social roles and forces. Ranging from turnstile to the transmitter, Vassos along with other industrial designers used the streamlined aesthetic to create visual unity among mechanical and electronic products, from home to office, from subway to skyline.

SiGe BiCMOS technology has many advantageous properties that, when leveraged, enable circuit design for extreme environments. This work will focus on designs targeted for space system avioinics platforms under the NASA ETDP program. The program specifications include operation under temperatures ranging from -180 C to +125 C and with radiation tolerance up to total ionizing dose of 100 krad with built-in single-event latch-up tolerance. To the author's knowledge, this work presents the first design and measurement of a wide temperature range enabled, radiation tolerant as built, RS-485 wireline transceiver in SiGe BiCMOS technology. This work also includes design and testing of a charge amplification channel front-end intended to act as the interface between a piezoelectric sensor and an ADC. An additional feature is the design and testing of a 50 Ohm output buffer utilized for testing of components in a lab setting.

Στην παρούσα διατριβή διερευνήθηκε το φαινόμενο της ύπαρξης διαφορών μεταξύ καταγραφών όμοιων ηλεκτρονικών οργάνων που μετρούν υπό τις ίδιες συνθήκες. Οι διαφορές πιθανώς οφείλονται στην επίδραση θορύβου που παράγεται από τα ίδια τα όργανα και παρουσιάζει διαφορετικά χαρακτηριστικά από όργανο σε όργανο (instrument dependent noise). Το φαινόμενο αυτό δεν έχει διερευνηθεί εκτενώς, ενώ παρουσιάζει μεγάλη σημασία αφού στο παρελθόν τα χαρακτηριστικά του θορύβου προερχόμενου από όργανα ίδιου τύπου θεωρούνταν σταθερά. Η διερεύνηση βασίστηκε σε σύγκριση καταγραφών από όργανα GPS ίδιου τύπου που μετρούσαν υπό τις ίδιες συνθήκες. Οι καταγραφές προήλθαν από πειράματα με δέκτες GPS ακίνητους και δέκτες που εκτελούσαν ελεγχόμενες ταλαντώσεις. Τα αποτελέσματα της σύγκρισης έδειξαν ότι ο θόρυβος των οργάνων παρουσιάζει διαφορές από όργανο σε όργανο. Η σύγκριση που πραγματοποιήθηκε περιελάμβανε: σύγκριση των στατιστικών χαρακτηριστικών (μέσος όρος, τυπική απόκλιση) και σύγκριση των φασματικών χαρακτηριστικών του θορύβου των οργάνων, έλεγχο συσχέτισης μεταξύ των οργάνων και έλεγχο χρονικής υστέρησης μεταξύ των οργάνων. Οι διαφορές στα στατιστικά χαρακτηριστικά του θορύβου των οργάνων εμφανίστηκαν μικρές. Οι κύριες διαφορές εμφανίστηκαν στα φασματικά χαρακτηριστικά του θορύβου από κάθε όργανο. Επίσης από την ανάλυση προέκυψε ότι ο θόρυβος δεν παρουσιάζει συσχέτιση από όργανο σε όργανο, ενώ δεν διαπιστώθηκε ύπαρξη χρονικής υστέρησης μεταξύ των οργάνων που εξετάστηκαν. Ο θόρυβος των οργάνων κάλυπτε συχνότητες από 0.001 μέχρι 0.2 Hz περίπου. Για μικρές συχνότητες ο θόρυβος των οργάνων χαρακτηρίζεται έγχρωμος (colored noise) ενώ για συχνότητες πάνω από 1 Hz ο θόρυβος των οργάνων χαρακτηρίζεται λευκός (white noise) με τυχαία χαρακτηριστικά. Τα παραπάνω αποτελέσματα αποτελούν ενδείξεις ότι ο θόρυβος που παράγεται από όργανα GPS ίδιου τύπου παρουσιάζει διαφορές που οφείλονται στις ιδιότητες του οργάνου. Στο μέλλον αξίζει να διερευνηθεί η επίδραση των διαφορών στις μετρήσεις, καθώς να γενικευθούν τα παραπάνω αποτελέσματα και για άλλους τύπους σύγχρονων ηλεκτρονικών οργάνων. / At the present study the differences between recordings obtained from the same instruments under the same conditions were examined. Differences are possibly owned to noise with different characteristics produced by each instrument. The case has not been covered yet and is important as noise produced by the same instruments under the same conditions is generally considered to have the same characteristics. The study was based on comparison of recordings from same GPS instruments measuring simultaneously under the same conditions. The recordings were obtained from experiments where GPS receivers were stationary or executing oscillations with known characteristics. Comparison between the recordings showed that differences exist in the noise produced by instruments of the same type. Our analysis included comparison of the statistical and spectral characteristics of the measurements and cross correlation analysis. The differences between the statistical characteristics were small while bigger differences existed in the spectral characteristics. Furthermore, no significant correlation was found between the noise produced by same instruments Significant noise frequencies existed in the band 0.001 to 0.2 Hz, with low frequency noise characterized as colored and high frequency (>1Hz) noise characterized as white. The above results indicate that instruments of the same type measuring under the same conditions may produce noise with different characteristics. Future studies should cover the effects of the differences mentioned above on GPS measurements, and also possible differences in instrumental noise for other types of instruments.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Em comunicaÃÃes cooperativas, dois ou mais terminais de transmissÃo sÃo combinados para aumentar a diversidade e/ou a potencia dos sinais que chegam a um determinado receptor. Portanto, mesmo que os dispositivos nÃo disponham de mais de uma antena, ou que entÃo haja uma grande perda por propagaÃÃo entre dois pontos comunicantes, os diversos elementos transmissores podem atuar como um arranjo virtual de antenas, obtendo-se assim vantagens dos sistemas de mÃltiplas antenas (MIMO), sobretudo o aumento da capacidade de transmissÃo. Recentemente, a chamada analise tensorial tem se mostrado uma abordagem eficiente entÃo para a estimaÃÃo de canais em sistemas com diversidade cooperativa. Contudo, nos poucos trabalhos dedicados a essa tarefa, a utilizaÃÃo da decomposiÃÃo tensorial PARAFAC para a modelagem dos sinais recebidos nÃo possibilitou o desenvolvimento de tÃcnicas de estimaÃÃo conjunta de canais e sÃmbolos. Com a idÃia de se evitar o uso de sequencias de treinamento, que limita a eficiÃncia espectral da transmissÃo por dedicar uma parte da largura de banda apenas para a tarefa de estimaÃÃo dos canais, o objetivo desta tese à prover novas estratÃgias de comunicaÃÃo, em termos de sistemas de transmissÃo e receptores semi-cegos, baseados em tensores adaptados a sistemas cooperativos MIMO unidirecionais de dois saltos. Dois sistemas de transmissÃo sÃo propostos utilizando uma codificaÃÃo espaÃo-temporal do tipo Khatri-Rao na fonte e duas estrategias de processamento Amplify-and-Forward (AF) no relay. Para estes sistemas, nomeados PT2-AF e NP-AF, os sinais recebidos no chamado nà de destino satisfazem os modelos tensoriais do tipo PARATUCK2 e Nested PARAFAC. Explorando as propriedades de unicidade destes modelos tensoriais estabelecidas nesta tese, vÃrios receptores semi-cegos sÃo derivados. Alguns destes receptores sÃo do tipo ALS, enquanto outros sÃo de soluÃÃes baseadas na factorizaÃÃo de produtos de Khatri-Rao. Resultados de simulaÃÃo sÃo apresentados para ilustrar os desempenhos dos receptores propostos em comparaÃÃo a alguns estimadores supervisionados. / In cooperative communication systems, two or more transmitting terminals are combined to increase the diversity and/or the power of the signals arriving at a particular receiver. Therefore, even if the devices do not have more than one antenna, or if a significant propaga- tion loss is present between the two communicating nodes, the various transmitting elements can act as a virtual antenna array, thus obtaining the benefits of the multiple antenna (MIMO) systems, especially the increase in the capacity. Recently, tensor decompositions have been introduced as an efficient approach for channel estimation in cooperative com- munication systems. However, among the few works devoted to this task, the utilization of the PARAFAC tensor decomposition for modeling the received signals did not allow the development of techniques for joint symbol and channel estimation. Aiming to avoid the use of pilot sequences, which limits the overall spectral efficiency by dedicating a portion of the bandwidth only for the channel estimation task, the objective of this thesis is to provide new tensor-based strategies, including transmission systems and semi-blind receivers, for one-way two-hop MIMO relaying systems. Based on a Khatri-Rao space-time coding at the source and two different Amplify-and-Forward (AF) relaying strategies, two transmission schemes are proposed. For these systems, named PT2-AF and NP-AF, the received signals at the destination node follow respectively a PARATUCK2 and a nested PARAFAC tensor model. Exploiting uniqueness properties of these tensor models which are established in the thesis, several semi-blind receivers are derived. Some of these receivers are of iterative form us- ing an ALS algorithm, whereas some other ones have closed-form solutions associated with Khatri-Rao factorizations. Some simulation results are finally presented to illustrate the per- formance of the proposed receivers which are compared to some state-of-the-art supervised techniques.

A tendência do mercado da microeletrônica é integrar em um mesmo chip sistemas eletrônicos completos, incluindo simultaneamente circuitos analógicos, digitais e RF. Por causa da complexidade do problema de projeto, a parte analógica e RF desses sistemas é o gargalo do desenvolvimento. Uma alternativa de projeto para circuitos analógicos é formular o projeto como um problema de otimização matemática conhecido como programação geométrica. As vantagens são: o ótimo global é obtido eficientemente, e é possível fazer automatização do projeto. A principal desvantagem é que não todos os parâmetros e equações que modelam um circuito são compatíveis com a forma desse problema de otimização. Os receptores para sistemas de comunicação modernos realizam o processo de downconvertion usando uma freqüência intermediária baixa ou diretamente em banda-base. As topologias de receptor Zero-IF e Low-IF são preferidas por sua alta capacidade de integração e baixo consumo de área e de potência. Os filtros analógicos são blocos de composição básicos nesses sistemas. Neste trabalho é desenvolvida uma metodologia de projeto baseada na aplicação de programação geométrica para projeto de filtros Gm-C. A metodologia de projeto foi usada para projetar filtros analógicos complexos e reais para os padrões de comunicação Bluetooth e Zigbee IEEE/802.15.4. Os resultados obtidos mostram que a metodologia de projeto proposta neste trabalho é uma solução efetiva para reduzir o tempo de projeto e otimizar o desempenho de filtros analógicos. / The tendency of the microelectronic market is to integrate in the same chip complete electronic systems, including digital, analog and RF circuits simultaneously. The analog part of those systems represents the bottleneck in the design process. The complexity of analog design makes this one an intuitive and creative process but time expensive. An alternative methodology for analog integrated circuits design is to represent the design as a mathematical optimization problem known as geometric programming. The advantages are: global optimum achieved efficiently, and the possibility of design automation. The main disadvantage, is that all the parameters or equations that characterize a circuit are not compatible with the form of this optimization problem. Modern receivers perform downconvertion of the signal using very low, or zero intermediate frequency. Zero-IF and Low-IF topologies are preferred because of their high integration capabilities, and low area and power consumption. Analog filters are basic building blocks of such systems. In this work, a design methodology based on geometric programming is developed, for automated and optimal design of Gm-C filters. The design methodology was used to design analog complex and real filters for the digital communications standards Bluetooth and Zigbee IEEE/802.15.4. The results show that the design methodology proposed in this work is an effective solution for fast, automated and optimal analog filter design

Massmedias framställning av socialbidragstagare   -     en diskursanalys av språkliga konstruktioner i svensk dagspress       Författare: Jennifer Engström           Institutionen för socialt arbete Examensarbete 15 hp Socialt arbete Socionomprogrammet             Höstterminen/Autumn term 2017 Handledare/Supervisor: Lennart Räterlinck English title: Mass media's representation of social welfare receivers – a discourse analysis of linguistic constructions in Swedish daily press Abstract  English title: Mass media's representation of social welfare receivers - a discourse analysis of linguistic constructions in Swedish daily press Svensk titel: Massmediers framställning av socialbidragstagare - en diskursanalys av språkliga konstruktioner i svensk dagspress Author/författare: Jennifer Engström   The purpose of this study was to examine how social welfare receivers is portrayed and constructed in Swedish daily press. The empirical data have consisted of twenty-one articles from the main national newspapers Dagens Nyheter and Svenska Dagbladet. The study had a qualitative disposition and the selection was made strategically to make sure the empirical data would be relevant to the study’s issues. The theoretical starting point was extracted from social constructivism and from Foucault’s theory about power and his discourse concept. The analysis was done with help of Foucault’s discursive analytic methods with focus on power, entities positioning, what was implicit in the articles and whom was given the space to be heard.   It was found that the descriptions of social welfare receivers were often negative and contained assumptions that were seldom expressly explained. The rhetoric constructions may contribute to the legitimation of the marginalisation of social welfare receivers in Sweden through the focus on political, financial and work-related aspects. The result showed that social welfare receivers were considered to be uneducated and incapable in most of the articles. The result also showed that the main point of view was from the author to the article or political.

Wireless systems, ranging from radio to optical frequencies, typically comprise two domains: the signal path and the local oscillator (LO) path. While signal processing is conventionally performed in the signal path, more recently, techniques that exploit LO-based signal processing are becoming increasingly popular. LO-based analog signal processing can be utilized for solving fundamental problems and for improving the performance of systems in a wide variety of applications that span radio to optical frequencies. In this dissertation, I explore LO-based signal processing to enable new functionalities and enhance performance in electrical, optical, and electro-optical circuits and systems. In the electro-optical domain, I use LO-based signal processing to improve the performance of a long-range Frequency-Modulated Continuous-Wave (FMCW) Light Detection and Ranging (LiDAR) system. As laser nonlinearity degrades the performance of ranging and imaging systems, it is essential to address this problem. In this dissertation, to linearize a laser, an integrated continuous-time Electro-Optical Phase-Locked Loop (EOPLL) is presented with a loop bandwidth equal to its reference frequency. Despite the high bandwidth, the proposed system is spurless, which is enabled by using Single-Sideband (SSB) and Harmonic-Reject mixing (HRM) techniques. These techniques are explored in Phase-Locked Loop (PLL) design for the first time. These features result in less area consumption and loss associated with the optical part of the system and increase the precision and accuracy of our long-range FMCW LIDAR significantly. In the electrical domain, I use LO engineering to address some of the challenges that exist in three different electrical systems including mm-wave Multi-Input Multi-Output (MIMO) systems, ultra-low power RF systems, and wideband mm-wave systems. In the first project, to alleviate the challenge of supporting a high data rate Input/Output (I/O) interface in a large-scale tiled mm-wave MIMO array, a single-wire interface (SWI) is used in this dissertation, and a 60GHz 4-element scalable MIMO transmitter (TX) prototype is designed. In our work, we use frequency-domain multiplexing (FDM) to simultaneously support the signals of four MIMO channels. Then, in our proposed FDM, HRM is utilized to generate the different frequencies at which the various IF signals are multiplexed. This enables us to multiplex and de-multiplex the four modulated signals simultaneously to/from the single-wire using multiple phases of only one LO. The technique proposed in this research significantly reduces the number of lines needed for LO and signal routing in a massive MIMO system. The second electrical project in this dissertation targets ultra-low power receivers at RF frequency. Wake-up receivers (WURX) are integral to reducing the power consumed by the main or primary RX in ultra-low power systems. Thus, the ability to share one antenna for both RXs is essential and results in a compact hybrid system. Furthermore, linearity and sensitivity are two fundamental criteria in these RXs. In order to improve the linearity of these systems, mixer-first RX architecture can be used for both RXs. However, mixer-first architecture has some drawbacks, like low gain and high noise figure (NF), which degrade the sensitivity of the system. Here, in our research, we implement a hybrid primary RX and WURX in which, first, a Quadrature Hybrid Coupler (QHC) is used to share one antenna between the two RXs and to achieve wideband input matching. Secondly, to address the problem of sensitivity in the mixer-first structure, we exploit a LO-assisted noise-canceling technique combined with a bottom-plate capacitor mixer-first receiver. This structure exploits implicit capacitive stacking which enables us to achieve passive LO-defined voltage gain, high linearity, and a low NF. In the last electrical project in this dissertation, I present a novel frequency-interleaved (FI) channel aggregation architecture for wideband mm-wave systems that relaxes the requirements of their Analog-to-Digital/Digital-to-Analog Converters (ADC/DAC) and consequently reduces the total cost and power consumption. In our proposed architecture, the input bandwidth is channelized into four sub-channels, which are individually up/downconverted from/to baseband, where they can be digitized with multiple lower rate subconverters. We use the idea of HRM in the channelizer to simultaneously down(up)convert four sub-channels with only one LO. Four chips, including two mm-wave RX and TX chips and two baseband RX and TX chips, are designed and tested to show the functionality of the entire system as a transceiver. Finally, I conclude this dissertation with an optical project which is a Silicon Photonic (SiP) simultaneous Mode and Wavelength Division (De)Multiplexer (MWD(De)MUX) for optical frequencies at C-band. I use an advanced 3D simulation tool, RSOFT software, to design and test this novel compact SiP structure. Our circuit uses a cascade of Mode Division Multiplexer (MDM) and Wavelength Division Multiplexer (WDM) stages for (de)multiplexing. A novel phase shifter introduced and used in this work is designed using two close waveguides on a CMOS compatible SiP platform, which results in reduced loss and size compared to conventional techniques.

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Fade and inter-fade duration data obtained from the three beacons at 12, 20, and 30 GHz aboard the OLYMPUS satellite were analyzed. The different types of signal impairments and their causes were highlighted and a literature survey conducted. Twelve months of fade and inter-fade data were analyzed and the results of these statistics are presented in the form of tables and figures. The analysis was done on both the monthly and annual data. These tables and figures show that at the higher fade levels, the number of fade events and the fade time is smaller than at the lower thresholds. For the same fade level the number of fade events and the fade time goes down as the fade duration which it exceeds is increased. Inter-fade durations also showed similar results. The fades exhibited seasonal dependencies. The number of fades (and consequently the fade time) were much higher for the months of May through August and for the months of March and December. The other months showed very little fade activity. A model was also constructed that can predict the fade time as a function of frequency, attenuation level, and fade duration interval. The predicted fade times agree well with the measured fade duration data. An alternate simplified version of the model is also presented. / Master of Science