Viterbi algorithm in continuous-phase frequency shift keying

The Viterbi algorithm, an application of dynamic programming, is widely used for estimation and detection problems in digital communications and signal processing. It is used to detect signals in communication channels with memory, and to decode sequential error-control codes that are used to enhance the performance of digital communication systems. The Viterbi algorithm is also used in speech and character recognition tasks where the speech signals or characters are modeled by hidden Markov models. This project explains the basics of the Viterbi algorithm as applied to systems in digital communication systems, and speech and character recognition. It also focuses on the operations and the practical memory requirements to implement the Viterbi algorithm in real-time. A forward error correction technique known as convolutional coding with Viterbi decoding was explored. In this project, the basic Viterbi decoder behavior model was built and simulated. The convolutional encoder, BPSK and AWGN channel were implemented in MATLAB code. The BER was tested to evaluate the decoding performance. The theory of Viterbi Algorithm is introduced based on convolutional coding. The application of Viterbi Algorithm in the Continuous-Phase Frequency Shift Keying (CPFSK) is presented. Analysis for the performance is made and compared with the conventional coherent estimator. The main issue of this thesis is to implement the RTL level model of Viterbi decoder. The RTL Viterbi decoder model includes the Branch Metric block, the Add-Compare-Select block, the trace-back block, the decoding block and next state block. With all done, we further understand about the Viterbi decoding algorithm

Codificación para corrección de errores con aplicación en sistemas de transmisión y almacenamiento de información

Tesis (DCI)--FCEFN-UNC, 2013Trata de una técnica de diseño de códigos de chequeo de paridad de baja densidad ( más conocidas por sigla en ingles como LDPC) y un nuevo algoritmo de post- procesamiento para la reducción del piso de erro

Proceedings of the Fifth International Mobile Satellite Conference 1997

Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial communications services. While previous International Mobile Satellite Conferences have concentrated on technical advances and the increasing worldwide commercial activities, this conference focuses on the next generation of mobile satellite services. The approximately 80 papers included here cover sessions in the following areas: networking and protocols; code division multiple access technologies; demand, economics and technology issues; current and planned systems; propagation; terminal technology; modulation and coding advances; spacecraft technology; advanced systems; and applications and experiments

Earth resources technology satellite operations control center and data processing facility. Book 1 - Systems studies Final report

Systems analysis for ERTS ground data handling system and operations control cente

A Process for the Restoration of Performances from Musical Errors on Live Progressive Rock Albums

In the course of my practice of producing live progressive rock albums, a significant challenge has emerged: how to repair performance errors while retaining the intended expressive performance. Using a practice as research methodology, I develop a novel process, Error Analysis and Performance Restoration (EAPR), to restore a performer’s intention where an error was assessed to have been made. In developing this process, within the context of my practice, I investigate: the nature of live albums and the groups to which I am accountable, a definition of performance errors, an examination of their causes, and the existing literature on these topics. In presenting EAPR, I demonstrate, drawing from existing research, a mechanism by which originally intended performances can be extracted from recorded errors. The EAPR process exists as a conceptual model; each album has a specific implementation to address the needs of that album, and the currently available technology. Restoration techniques are developed as part of this implementation. EAPR is developed and demonstrated through my work restoring performances on a front-line commercial live release, the Creative Submission Album. The specific EAPR implementation I design for it is laid out, and detailed examples of its techniques demonstrated

Music and Digital Media

Anthropology has neglected the study of music. Music and Digital Media shows how and why this should be redressed. It does so by enabling music to expand the horizons of digital anthropology, demonstrating how the field can build interdisciplinary links to music and sound studies, digital/media studies, and science and technology studies. Music and Digital Media is the first comparative ethnographic study of the impact of digital media on music worldwide. It offers a radical and lucid new theoretical framework for understanding digital media through music, showing that music is today where the promises and problems of the digital assume clamouring audibility. The book contains ten chapters, eight of which present comprehensive original ethnographies; they are bookended by an authoritative introduction and a comparative postlude. Five chapters address popular, folk, art and crossover musics in the global South and North, including Kenya, Argentina, India, Canada and the UK. Three chapters bring the digital experimentally to the fore, presenting pioneering ethnographies of anextra-legal peer-to-peer site and the streaming platform Spotify, a series of prominent internet-mediated music genres, and the first ethnography of a global software package, the interactive music platform Max. The book is unique in bringing ethnographic research on popular, folk, art and crossover musics from the global North and South into a comparative framework on a large scale, and creates an innovative new paradigm for comparative anthropology. It shows how music enlarges anthropology while demanding to be understood with reference to classic themes of anthropological theory. Praise for Music and Digital Media ‘Music and Digital Media is a groundbreaking update to our understandings of sound, media, digitization, and music. Truly transdisciplinary and transnational in scope, it innovates methodologically through new models for collaboration, multi-sited ethnography, and comparative work. It also offers an important defense of—and advancement of—theories of mediation.’ Jonathan Sterne, Communication Studies and Art History, McGill University 'Music and Digital Media is a nuanced exploration of the burgeoning digital music scene across both the global North and the global South. Ethnographically rich and theoretically sophisticated, this collection will become the new standard for this field.' Anna Tsing, Anthropology, University of California at Santa Cruz 'The global drama of music's digitisation elicits extreme responses – from catastrophe to piratical opportunism – but between them lie more nuanced perspectives. This timely, absolutely necessary collection applies anthropological understanding to a deliriously immersive field, bringing welcome clarity to complex processes whose impact is felt far beyond what we call music.' David Toop, London College of Communication, musician and writer ‘Spanning continents and academic disciplines, the rich ethnographies contained in Music and Digital Media makes it obligatory reading for anyone wishing to understand the complex, contradictory, and momentous effects that digitization is having on musical cultures.’ Eric Drott, Music, University of Texas, Austin ‘This superb collection, with an authoritative overview as its introduction, represents the state of the art in studies of the digitalisation of music. It is also a testament to what anthropology at its reflexive best can offer the rest of the social sciences and humanities.’ David Hesmondhalgh, Media and Communication, University of Leeds ‘This exciting volume forges new ground in the study of local conditions, institutions, and sounds of digital music in the Global South and North. The book’s planetary scope and its commitment to the “messiness” of ethnographic sites and concepts amplifies emergent configurations and meanings of music, the digital, and the aesthetic.’ Marina Peterson, Anthropology, University of Texas, Austi

Music and Digital Media: A planetary anthropology

Anthropology has neglected the study of music. Music and Digital Media shows how and why this should be redressed. It does so by enabling music to expand the horizons of digital anthropology, demonstrating how the field can build interdisciplinary links to music and sound studies, digital/media studies, and science and technology studies. Music and Digital Media is the first comparative ethnographic study of the impact of digital media on music worldwide. It offers a radical and lucid new theoretical framework for understanding digital media through music, showing that music is today where the promises and problems of the digital assume clamouring audibility. The book contains ten chapters, eight of which present comprehensive original ethnographies; they are bookended by an authoritative introduction and a comparative postlude. Five chapters address popular, folk, art and crossover musics in the global South and North, including Kenya, Argentina, India, Canada and the UK. Three chapters bring the digital experimentally to the fore, presenting pioneering ethnographies of an extra-legal peer-to-peer site and the streaming platform Spotify, a series of prominent internet-mediated music genres, and the first ethnography of a global software package, the interactive music platform Max. The book is unique in bringing ethnographic research on popular, folk, art and crossover musics from the global North and South into a comparative framework on a large scale, and creates an innovative new paradigm for comparative anthropology. It shows how music enlarges anthropology while demanding to be understood with reference to classic themes of anthropological theory

Music and Digital Media

Anthropology has neglected the study of music. Music and Digital Media shows how and why this should be redressed. It does so by enabling music to expand the horizons of digital anthropology, demonstrating how the field can build interdisciplinary links to music and sound studies, digital/media studies, and science and technology studies. Music and Digital Media is the first comparative ethnographic study of the impact of digital media on music worldwide. It offers a radical and lucid new theoretical framework for understanding digital media through music, showing that music is today where the promises and problems of the digital assume clamouring audibility. The book contains ten chapters, eight of which present comprehensive original ethnographies; they are bookended by an authoritative introduction and a comparative postlude. Five chapters address popular, folk, art and crossover musics in the global South and North, including Kenya, Argentina, India, Canada and the UK. Three chapters bring the digital experimentally to the fore, presenting pioneering ethnographies of anextra-legal peer-to-peer site and the streaming platform Spotify, a series of prominent internet-mediated music genres, and the first ethnography of a global software package, the interactive music platform Max. The book is unique in bringing ethnographic research on popular, folk, art and crossover musics from the global North and South into a comparative framework on a large scale, and creates an innovative new paradigm for comparative anthropology. It shows how music enlarges anthropology while demanding to be understood with reference to classic themes of anthropological theory. Praise for Music and Digital Media ‘Music and Digital Media is a groundbreaking update to our understandings of sound, media, digitization, and music. Truly transdisciplinary and transnational in scope, it innovates methodologically through new models for collaboration, multi-sited ethnography, and comparative work. It also offers an important defense of—and advancement of—theories of mediation.’ Jonathan Sterne, Communication Studies and Art History, McGill University 'Music and Digital Media is a nuanced exploration of the burgeoning digital music scene across both the global North and the global South. Ethnographically rich and theoretically sophisticated, this collection will become the new standard for this field.' Anna Tsing, Anthropology, University of California at Santa Cruz 'The global drama of music's digitisation elicits extreme responses – from catastrophe to piratical opportunism – but between them lie more nuanced perspectives. This timely, absolutely necessary collection applies anthropological understanding to a deliriously immersive field, bringing welcome clarity to complex processes whose impact is felt far beyond what we call music.' David Toop, London College of Communication, musician and writer ‘Spanning continents and academic disciplines, the rich ethnographies contained in Music and Digital Media makes it obligatory reading for anyone wishing to understand the complex, contradictory, and momentous effects that digitization is having on musical cultures.’ Eric Drott, Music, University of Texas, Austin ‘This superb collection, with an authoritative overview as its introduction, represents the state of the art in studies of the digitalisation of music. It is also a testament to what anthropology at its reflexive best can offer the rest of the social sciences and humanities.’ David Hesmondhalgh, Media and Communication, University of Leeds ‘This exciting volume forges new ground in the study of local conditions, institutions, and sounds of digital music in the Global South and North. The book’s planetary scope and its commitment to the “messiness” of ethnographic sites and concepts amplifies emergent configurations and meanings of music, the digital, and the aesthetic.’ Marina Peterson, Anthropology, University of Texas, Austi

Epistemic tools: the phenomenology of digital musical instruments

Digital music technologies, and instruments in particular, are the result of specific systems of thought that define and enframe the user’s creative options. Distinctive divisions between digital and acoustic instruments can be traced, contrasting the conceptually based design of software with the affordances and constraints of physical artefacts. Having lost the world’s gift of physical properties, the digital instrument builder becomes more than a mere luthier. The process of designing and building the instrument is transformed into a process of composition, for it typically contains a greater degree of classification and music theory than its acoustic counterpart. Part I of this thesis begins by framing musical systems in the context of the philosophy of technology. Here technological conditions are questioned and theories introduced that will assist the investigation into the relationship between creativity and technology. After this general grounding, the ramifications digital technologies pose to the human body are explored in the context of human expression through tool use. The human-machine relationship is described from phenomenological perspectives and relevant theories of cognitive science. This analysis serves as a foundation for the concept of epistemic tools, defined as the mechanism whereby techno-cultural models are inscribed into technological artefacts. The cultural element of tool use and tool origins is therefore emphasised, an aspect that is highly relevant in musical technologies. Part I thus frames the material properties of acoustic and digital instruments in relation to human culture, cognition, performance and epistemology. Part II contextualises these theories in practice. The ixiQuarks, the live improvisation musical environment that resulted from the current research, are presented as a system addressing some of the vital problems of musical performance with digital systems (such as the question of embodiment and theoretical inscriptions), proposing an innovative interaction model for screen-based musical instruments. The concept of virtual embodiment is introduced and framed in the context of the ixi interaction model. Two extensive user studies are described that support the report on ixiQuarks. Furthermore, comparative surveys on the relationship between expression and technology are presented: a) the phenomenology of musical instruments, where the divergence between the acoustic and the digital is investigated; b) the question of expressive freedom versus time constraints in musical environments is explored with practitioners in the field; and c) the key players in the design of audio programming environments explain the rationale and philosophy behind their work. These are the first major surveys of this type conducted to date, and the results interweave smoothly with the observations and findings in the chapters on the nature and the design of digital instruments that make up the majority of Part II. This interdisciplinary research investigates the nature of making creative tools in the digital realm, through an active, philosophically framed and ethnographically inspired study, of both practical and theoretical engagement. It questions the nature of digital musical instruments, particularly in comparison with acoustic instruments. Through a survey of material epistemologies, the dichotomy between the acoustic and the digital is employed to illustrate the epistemic nature of digital artefacts, necessitating a theory of epistemic tools. Consequently virtual embodiment is presented as a definition of the specific interaction mode constituting human relations with digital technologies. It is demonstrated that such interactions are indeed embodied, contrasting common claims that interaction with software is a disembodied activity. The role of cultural context in such design is emphasised, through an analysis of how system design is always an intricate process of analyses, categorisations, normalisations, abstractions, and constructions; where the design paths taken are often defined by highly personal, culturally conditioned and often arbitrary reasons. The dissertation therefore dissects the digital musical instrument from the perspectives of ontology, phenomenology and epistemology. Respective sections in Part I and Part II deal with these views. The practical outcome of this research – the ixiQuarks – embodies many of the theoretical points made on these pages. The software itself, together with the theoretical elucidation of its context, should therefore be viewed as equal contributions to the field of music technology. The thesis closes by considering what has been achieved through these investigations of the technological context, software development, user studies, surveys, and the phenomenological and epistemological enquiries into the realities of digital musical instruments, emphasising that technology can never be neutral