Σκοπός αυτής της διπλωματικής εργασίας είναι η σχεδίαση και υλοποίηση συνθέτη συχνοτήτων διπλού βρόχου σε συχνότητες 3-6 GHz για ασύρματες εφαρμογές UWB και HiperLAN2. Ο συνθέτης συχνοτήτων σχεδιάστηκε με διακριτά στοιχεία, χρησιμοποιώντας την αρχιτεκτονική του βρόχου κλειδωμένης φάσης (PLL) και λειτουργεί με 2 τρόπους, είτε παράγοντας σήματα συχνότητας από 3168 MHz έως 6336 MHz με βήμα συχνότητας 528 MHz, είτε παράγοντας σήματα συχνότητας από 4800 MHz έως 5000 MHz με βήμα συχνότητας 10 MHz. Παρά το γεγονός ότι η αρχιτεκτονική διπλού βρόχου έχει αντικατασταθεί από την αρχιτεκτονική fractional-N για λόγους κατανάλωσης και κόστους, πλεονεκτεί σε εφαρμογές ασύρματων δικτύων με αυστηρές απαιτήσεις ως προς την ακρίβεια της παραγόμενης συχνότητας και το θόρυβο φάσης. Η απλή αρχιτεκτονική integer-N δεν είναι επαρκής για την εκπλήρωση των απαιτήσεων σε μεγάλη ευκρίνεια και μικρό θόρυβο φάσης, λόγω του περιορισμένου εύρους ζώνης του βρόχου και του μεγάλου λόγου διαίρεσης Ν του διαιρέτη συχνοτήτων του βρόχου. Με την αρχιτεκτονική διπλού βρόχου χρησιμοποιούμε δυο βρόχους για να αμβλύνουμε την αντίθεση μεταξύ των παραπάνω παραγόντων, οι οποίοι καθορίζουν τη συμπεριφορά και την απόδοση του συνθέτη συχνοτήτων. Με τη χρήση διακριτών στοιχείων για την υλοποίηση των δυο βρόχων αποσκοπούμε σε καλύτερη συμπεριφορά του συστήματος ως προς το θόρυβο φάσης, καθώς και σε πιο ευέλικτο σχεδιασμό, που δίνει τη δυνατότητα μείωσης της ισχύος των ανεπιθύμητων συνιστωσών του σήματος αναφοράς στην έξοδο του συστήματος. / The purpose of this diploma thesis is the design and implementation of a dual loop frequency synthesizer, operating at frequencies ranging from 3 to 6 GHz, for wireless network applications, using UWB and HiperLAN2 standards. The frequency synthesizer’s design was based on dual loop synthesizer architecture and the use of modular components. The designed frequency synthesizer is able to function in 2 modes, by either producing signals in the frequency range of 3168 MHz - 6336 MHz with 528 MHz resolution, or signals in the frequency range of 4800 MHz - 5000 MHz with 10 MHz resolution. Although the dual loop architecture has long been replaced by the fractional-N architecture due to increased cost and power consumption, it is more suitable in wireless network applications demanding high precision in frequency synthesis and low phase noise. The integer-N architecture fails to satisfy these demands, due to the limited loop bandwidth and the large division ratio Ν of the loop’s frequency divider. The dual loop architecture uses two loops in order to alleviate the opposing demands in high frequency synthesis accuracy and low phase noise, which determine the behavior and performance of the frequency synthesizer. The use of modular components aims at better phase noise performance, as well as a more flexible design, thus resulting in a more efficient power dissipation of the spurious components of the reference signal at the synthesizer output.

Existem inúmeras técnicas de síntese de áudio utilizadas atualmente em instrumentos musicais profissionais, dentre as quais as mais fundamentais são a síntese aditiva e a síntese subtrativa. A síntese subtrativa se tornou popular e foi muito explorada entre as décadas de 60 e 70 com a criação de módulos analógicos de hardware que podiam ser interconectados, criando o conceito de sintetizador analógico modular. Apesar do uso deste tipo de sintetizador ter diminuído durante as décadas subsequentes, nos últimos anos sua utilização voltou a crescer e diversos modelos deste tipo de instrumento são vendidos atualmente, porém em geral a preços elevados. Sintetizadores digitais também disponibilizam a técnica de síntese subtrativa utilizando componentes eletrônicos customizados e desenvolvidos pelos fabricantes de sintetizadores com o intuito de utilizar avançadas técnicas de processamento de sinais, o que ainda mantém seus preços elevados. Neste trabalho investigamos a hipótese de que é possível desenvolver um instrumento musical funcional e de qualidade com recursos limitados de processamento, e exploramos essa hipótese implementando síntese subtrativa em uma plataforma acessível e de baixo custo. O desenvolvimento é baseado em linguagem orientada a objetos para criação de módulos de software replicando as características dos módulos encontrados em sintetizadores analógicos modulares. Com esta abordagem, obtemos um software modular que pode ser facilmente modificado baseado nas preferências do programador. A implementação foi testada na plataforma Arduino Due, que é uma plataforma de baixo custo e contém um processador 32-bits ARM 84 MHz. Foi possível adicionar osciladores com algoritmo anti-aliasing, filtros, geradores de envelope, módulo de efeito, uma interface MIDI e um teclado externo, obtendo assim um sintetizador subtrativo completo. Além disto, incluímos no desenvolvimento a implementação de um órgão baseado em síntese aditiva, com polifonia completa e inspirado na arquitetura de órgãos clássicos, mostrando a possibilidade de possuir dois importantes e poderosos métodos de síntese em uma plataforma acessível e de baixo custo. Com esta implementação aberta e pública, buscamos contribuir com o movimento maker e faça-você-mesmo, incentivando novos desenvolvimentos nesta área, em especial na computação e engenharia, aumentando o uso e acesso a instrumentos musicais eletrônicos e a criatividade musical. / Subtractive and additive synthesis are two powerful sound synthesis techniques that caused a revolution when the first electronic and electro mechanic music instruments started to appear some decades ago. Subtractive synthesis became very popular during the 60s and 70s after the creation of analog hardware modules that could be interconnected, creating the concept of the modular synthesizers. After the initial impact, for some years these instruments faced a slow-down in its usage, a tendency that was reverted on the past decade. Nevertheless, the prices of these instruments are often high. Digital synthesizers also offer the subtractive synthesis technique, by using customized electronic components designed and developed by the synthesizers vendors in order to use the most up-to-date technologies and signal processing techniques, which also leads to high prices. In this project, we investigate the hypothesis that it is possible to design and develop a good quality music instrument with low budget electronic components and limited processing capabilities, by implementing this on a low budget and easy to use platform. The development is based on object oriented design, creating software modules that replicates the functionalities of analog synthesizer hardware modules. With this approach, we have a modular software that can be easily changed based on programmers’ preferences. The implementation was tested on the Arduino Due board, which is a cheap, easy to use and widely available platform and powered by a 32-bits ARM 84Mhz processor. We were able to add oscillators with anti-aliasing algorithms, filters, envelope generators, delay effects, a MIDI interface and a keybed, making a complete synthesizer. In addition to this, we included an additive synthesis organ design with full polyphony based on classic organs design, demonstrating the possibility of having two powerful synthesis methods on a cheap and widely available platform. With this design, suitable for low cost platforms, we intend to contribute to the maker movement and encourage new implementations in this area, especially in the computing and engineering fields, increasing the usage and access to (electronic) musical instruments and musical creativity.

Existem inúmeras técnicas de síntese de áudio utilizadas atualmente em instrumentos musicais profissionais, dentre as quais as mais fundamentais são a síntese aditiva e a síntese subtrativa. A síntese subtrativa se tornou popular e foi muito explorada entre as décadas de 60 e 70 com a criação de módulos analógicos de hardware que podiam ser interconectados, criando o conceito de sintetizador analógico modular. Apesar do uso deste tipo de sintetizador ter diminuído durante as décadas subsequentes, nos últimos anos sua utilização voltou a crescer e diversos modelos deste tipo de instrumento são vendidos atualmente, porém em geral a preços elevados. Sintetizadores digitais também disponibilizam a técnica de síntese subtrativa utilizando componentes eletrônicos customizados e desenvolvidos pelos fabricantes de sintetizadores com o intuito de utilizar avançadas técnicas de processamento de sinais, o que ainda mantém seus preços elevados. Neste trabalho investigamos a hipótese de que é possível desenvolver um instrumento musical funcional e de qualidade com recursos limitados de processamento, e exploramos essa hipótese implementando síntese subtrativa em uma plataforma acessível e de baixo custo. O desenvolvimento é baseado em linguagem orientada a objetos para criação de módulos de software replicando as características dos módulos encontrados em sintetizadores analógicos modulares. Com esta abordagem, obtemos um software modular que pode ser facilmente modificado baseado nas preferências do programador. A implementação foi testada na plataforma Arduino Due, que é uma plataforma de baixo custo e contém um processador 32-bits ARM 84 MHz. Foi possível adicionar osciladores com algoritmo anti-aliasing, filtros, geradores de envelope, módulo de efeito, uma interface MIDI e um teclado externo, obtendo assim um sintetizador subtrativo completo. Além disto, incluímos no desenvolvimento a implementação de um órgão baseado em síntese aditiva, com polifonia completa e inspirado na arquitetura de órgãos clássicos, mostrando a possibilidade de possuir dois importantes e poderosos métodos de síntese em uma plataforma acessível e de baixo custo. Com esta implementação aberta e pública, buscamos contribuir com o movimento maker e faça-você-mesmo, incentivando novos desenvolvimentos nesta área, em especial na computação e engenharia, aumentando o uso e acesso a instrumentos musicais eletrônicos e a criatividade musical. / Subtractive and additive synthesis are two powerful sound synthesis techniques that caused a revolution when the first electronic and electro mechanic music instruments started to appear some decades ago. Subtractive synthesis became very popular during the 60s and 70s after the creation of analog hardware modules that could be interconnected, creating the concept of the modular synthesizers. After the initial impact, for some years these instruments faced a slow-down in its usage, a tendency that was reverted on the past decade. Nevertheless, the prices of these instruments are often high. Digital synthesizers also offer the subtractive synthesis technique, by using customized electronic components designed and developed by the synthesizers vendors in order to use the most up-to-date technologies and signal processing techniques, which also leads to high prices. In this project, we investigate the hypothesis that it is possible to design and develop a good quality music instrument with low budget electronic components and limited processing capabilities, by implementing this on a low budget and easy to use platform. The development is based on object oriented design, creating software modules that replicates the functionalities of analog synthesizer hardware modules. With this approach, we have a modular software that can be easily changed based on programmers’ preferences. The implementation was tested on the Arduino Due board, which is a cheap, easy to use and widely available platform and powered by a 32-bits ARM 84Mhz processor. We were able to add oscillators with anti-aliasing algorithms, filters, envelope generators, delay effects, a MIDI interface and a keybed, making a complete synthesizer. In addition to this, we included an additive synthesis organ design with full polyphony based on classic organs design, demonstrating the possibility of having two powerful synthesis methods on a cheap and widely available platform. With this design, suitable for low cost platforms, we intend to contribute to the maker movement and encourage new implementations in this area, especially in the computing and engineering fields, increasing the usage and access to (electronic) musical instruments and musical creativity.

nÃo hà / O uso de diferentes mÃtodos de sonificaÃÃo de dados meteorolÃgicos e geofÃsicos à recorrente tanto em aplicaÃÃes cientÃficas quanto no contexto da criaÃÃo artÃstica. PropÃe-se, atravÃs de diferentes abordagens ao longo do processo de pesquisa, a criaÃÃo de uma sÃrie de sintetizadores e dispositivos sonoros sensÃveis à variaÃÃes de intensidade do vento, da luminosidade e da temperatura ambiente. Com o intuito de explorar as potencialidades do uso da sonificaÃÃo de dados de forÃas da natureza como mÃtodo de composiÃÃo sonora e musical, utilizam-se diversos sensores para controlar parÃmetros distintos do processo de sÃntese sonora digital. AtravÃs da experimentaÃÃo de circuitos e cÃdigos de programaÃÃo em Arduino, busca-se analisar os fatores que influenciam diferentes aspectos do processo de composiÃÃo junto aos fenÃmenos meteorolÃgicos. à apresentado o processo de desenvolvimento de trÃs sintetizadores que sÃo utilizados em diferentes ocasiÃes, alÃm da construÃÃo de uma mÃquina sonificadora e a produÃÃo de registros diversos do processo de elaboraÃÃo dos protÃtipos. Com base nas experimentaÃÃes realizadas, identificam-se aspectos pertinentes à atuaÃÃo de elementos da natureza como forÃas criativas durante o processo de composiÃÃo sonora e musical. / The use of different methods of sonification of meteorological and geophysical data is recurrent both in scientific applications and in the context of artistic creation. It is proposed, through different approaches throughout the research process, the creation of a series of synthesizers and sound devices sensitive to variations of wind intensity, luminosity and ambient temperature. In order to explore the potentialities of using sonification of forces of nature as a method of sound and musical composition, several sensors are used to control different parameters of the digital sound synthesis process. Through the experimentation of circuits and programming codes in Arduino, it is sought to analyze the factors that influence different aspects of the composition process with the meteorological elements. The process of development of three synthesizers that are used in different occasions is presented, along with the construction of a sonifying machine and the production of diverse material about the process of elaboration of the prototypes. Based on the experiments carried out, aspects pertinent to the performance of elements of nature as creative forces during the process of sound and musical composition are identified.

Thesis: M.S., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 1976 / Includes bibliographical references. / M.S. / M.S. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science

No description available.

Syftet med denna studie var att beskriva mätmetoder, som mäter träets egenskaper med hjälp av vågrörelser respektive mätmetoder som mäter träds egna vågrörelser. Vidare att undersöka hur människor uppfattar musik från trädens egna ljud (vågrörelser). Resultaten visar att det finns flera olika mätmetoder som främst mäter kvalité i träd och virke. Ytterligare två mätmetoder finns och de tar hjälp av sensorer, synthesizers och en örontrumpet, och mäter främst elektriska impulser, ljud och ljudvågor. Resultaten visar även att människor är positivt inställda till musik som kommer från träden. Slutsatsen som kan dras från detta arbete är att det finns många olika sätt att mäta och lyssna på träden på. / The purpose of this study was to describe measurement methods, which measure the properties of the wood using wave movements and measurement methods that measure the tree's own wave movements. Further to investigate how people perceive music from the trees' own sounds (wave movements). The results show that there are several different measuring methods that primarily measure quality in trees and wood. Two other measuring methods are available, and they use sensors, synthesizers and an ear trumpet, and mainly measure electrical impulses, sounds and sound waves. The results also show that people are positively attuned to music that come from trees. The conclusion that can be drawn from this work is that there are many different ways to measure and listen to the trees.

VOTRAX is a commercially available voice synthesizer for use with a digital computer. This thesis describes the design and implementation of a VOTRAX terminal for use with the Fairchild F24 computer. Chapters of the thesis consider the audio response technology, some characteristics of Phonetic English Speech, configuration of hardware, and describe the PHONO computer program which was developed. The last chapter discusses the advantages of the VOTRAX voice synthesizer and proposes a future version of the system with a time-sharing host computer.

The socio-musical practice of sampling is closely associated with the re-use of pre-existing sound recordings and the technological processes of looping. These practices, based on appropriation and repetition, have been particularly common within the genres of hip-hop and Electronic Dance Music (EDM). Yet early digital sampling instruments such as the Fairlight Computer Musical Instrument (CMI) were not designed for these purposes. The technologists at Fairlight Instruments in Australia were primarily interested in the use of digital synthesis to imitate the sounds of acoustic instruments; sampling was a secondary concern. In the first half of the thesis, I follow digital sampling instruments like the Fairlight CMI and the E-mu Emulator by drawing on interviews with their designers and users to trace how they were used to sample the sounds of everyday life, loop sequenced patterns of sampled sounds, and sample extracts from pre-existing sound recordings. The second half of the thesis consists of case studies that follow the users of digital sampling technologies across a range of socio-musical worlds to examine the diversity of contemporary sampling practices. Using concepts from the field of Science and Technology Studies (STS), this thesis focuses on the ‘user-technology nexus’ and continues a shift in the writing of histories of technologies from a focus on the designers of technologies towards the contexts of use and ‘the co-construction’ or ‘mutual shaping’ of technologies and their users. As an example of the ‘interpretative flexibility’ of music technologies, digital sampling technologies were used in ways unimagined by their designers and sampling became synonymous with re-appropriation. My argument is that a history of digital sampling technologies needs to be a history of both the designers and the users of digital sampling technologies.

A fully integrated, fast-locking fractional-N frequency synthesizer is proposed and demonstrated in this work. In this design, to eliminate the need for large, inaccurate capacitors and resistors in a loop filter, an analog continuous-time loop filter whose performance is sensitive to process and temperature variations and aging has been replaced with a programmable digital Finite Impulse Response (FIR) filter. In addition, using the adaptive loop gain control proportional to the frequency difference, the frequency-locking time has been reduced. Also, the phase noise and spurs have been reduced by a Multi-stAge noise SHaping (MASH) controlled Fractional Frequency Detector (FFD) that generates a digital output corresponding directly to the frequency difference. The proposed frequency synthesizer provides many benefits in terms of high integration ability, technological robustness, fast locking time, low noise level, and multimode flexibility. To prove performance of the proposed frequency synthesizer, the frequency synthesizers analysis, design, and simulation have been carried out at both the system and the circuit levels. Then, the performance was also verified after fabrication and packaging.