Cellular digital packet data (CDPD) is a new service for wide-area data communication with wireless mobile users. CDPD system uses the existing infrastructure of the analog Advanced Mobile Phone Service (AMPS) cellular telephone network to transmit data with a channel hopping technique. The CDPD system employs Gaussian minimum shift keying (GMSK) as a modulation scheme and a Reed-Solomon code for error control to transmit high-quality data in the mobile and wireless environment. Most current CDPD receivers use errors only decoding of the Reed-Solomon code, although an improved errors and erasures decoding technique would also be possible. This thesis undertakes a performance evaluation of the CDPD system with an errors and erasures decoder for the Reed-Solomon coding. A thorough system simulation is conducted for both white Gaussian noise and flat Rayleigh fading channel environments. Results show that improved coding gains of 0.5 ~ 1 dB are possible for the additive white Gaussian noise channel and improved coding gains of 1.9 ~ 2.7 dB are possible for the fading channel. / Master of Science

The word "faith" is probably one of the most ambiguous words in the English language. It is used in different ways by different people at any given time to mean any number of feelings, actions or emotions. For some, faith is synonymous with religion, for others it represents belief and yet others use it to mean loyalty. Faith must have a meaning that is distinctly its own. Yet what is that meaning? Is there a way of defining faith that is understandable to all people? This paper strives to provide such a definition. In order to achieve this goal, the conceptions of faith as they are explained separately by Paul Tillich, John Hick and Robert Solomon are analyzed and combined with one another in order to formulate a universally applicable working definition of "faith". This paper seeks to provide readers with an understanding of what faith is, what it is not and how it functions in their lives and the lives of their fellow man. This is done in the hope of bringing about a recognition that faith is an active process employed by -all--people regardless of what their faith is directed toward. With this definition of "faith'', perhaps new and clearer lines of communication between the secular and spiritual communities can be opened.

Este trabalho investiga a decodificação turbo de códigos produto construídos a partir de códigos de Reed-Solomon sobre constelações QAM. Por meio da geometria euclidiana da constelação utilizada e das relações dos elementos de campo de Galois utilizados na codificação Reed-Solomon com os símbolos pertencentes ao alfabeto de modulação, é proposto um algoritmo de decodificação que utiliza a localização geométrica dos símbolos recebidos no processo de decodificação turbo. Tanto a primeira etapa da decodificação SISO baseada no algoritmo de Chase, como a extração da informação extrínseca baseada no algoritmo proposto por Pyndiah, são tratadas pelo uso de uma abordagem geométrica sobre o espaço euclidiano. Os resultados de simulação utilizando o algoritmo proposto coincidem com aqueles usando a decomposição e análise pragmática binária, sendo que a abordagem apresentada conduz a simplificações e otimizações em relação à metodologia binária no que ser refere à implementação dos possíveis esquemas de decodificação. / This work investigates the turbo decoding of product codes built using Reed- Solomon codes in QAM constellations. Using the euclidian geometry of the constellation and the relations of the Galois field elements used in the Reed-Solomon code and the modulation alphabet, a decoding algorithm for the turbo decoding process is proposed using the geometric localization of the received symbol. Both the first stage of the SISO decoding based on the Chase algorithm, as the calculation of the extrinsic information based on the Pyndiah algorithm, are treated using the geometric approach in the euclidian space. The simulations show that this algorithm gives similar performance results as the pragmatic binary decomposition approach, and leads to simplifications and optimizations in decoding implementations schemes compared to the former.

Thesis (Ph.D. (English studies)) --University of Limpopo, 2012 / This thesis aims to explore Sol T. Plaatje's use of Setswana and in that way explain primarily the nature and extent of his linguistic contributions to the rise, growth and development of the language as a modern communication means in South Africa. To obtain greater understanding of Plaatje's contribution, his Setswana translation of two Shakespeare plays, his paremiology, patronyms and onomastic examples are investigated through tools adapted from the rhetoric field, literary criticism, discourse analysis, pragmatics, sociolinguistics and language planning. Furthermore, by employing traditional grammar methodologies combined with conceptual frameworks derived from Transformational Generative principles, Plaatje’s work is descriptively exposed. The analysis of certain Plaatjean products seeks to bare the intralinguistic features of the Setswana variety or the Serolong forms he employs in the translations, the Diane proverbs, some folktales of A Sechuana Reader and related prose passages. Instances of the Serolong lect or his idiolect are treated as data bearing textual evidence of his efforts to preserve, elaborate and develop the broader Setswana sociolect that he perceives as in decline under English linguistic imperialism. The role he played in his native language's evolution is traced by trawling through documents and publications that presumably convey Plaatje's development policy and plan for Setswana. The main findings of the textual and/or contrastive analyses on selected portions of his Diane proverb collection and Setswana translations of Shakespeare, i.e. Comedy of Errors and Julius Caesar (renamed Diphosophoso and Dintshontsho tsa bo-Juliuse Kesara), are that his manipulation of Setswana morpho-phonological, lexico-semantic features and syntactic forms is characterized by innovative expression. Plaatje’s use of creative translation strategies including well-formed discourse patterns further reveal of several linguistic changes and advances in early 20th century Setswana. (vii). His usage of the Serolong variety in domains as different as journalism, ethnic history, story-telling, court interpreting, lexicography, onomastics and patronymy, provides evidence of a pioneering exercise of his native tongue’s expressive musculature. As such, the works resonate with his re-vitalization inputs for the sociolect to cope with the communication demands and challenges of a rapidly changing society. Research analysis of the linguistic discourse patterns in his writings thus uncovers the significant contributions he made to Setswana’s evolution, across several literary genres. While recognizing the study’s limitations owing to a focus on Plaatje’s linguistic productions only, the scope helped open up avenues for further and deeper investigation. Firstly, the enquiry appears to confirm the view that he was a language developer with literary and linguistic skills deserving greater recognition and high valorization. Secondly, Plaatje’s endeavours to grow and advance Setswana should serve as a model for contemporary language development policies and plans which African sociolinguists could adopt, adapt and/or emulate. The thesis makes a definite contribution to scholarly debates and discussions centering on the direction of African language planning and development. As such, research of Plaatje’s contributions are recommended for research to break new ground in areas like, orthography modernization, ethnolinguistic lexicology, editing and the writing of thesauruses or dictionaries for marginalized South African languages like Setswana. This is crucial especially because African intellectuals and leaders like Plaatje apparently address the problems facing their native languages from a developmental and socio-political angle. The holistic approach evidenced in Plaatje’s writing of Native Life, Mhudi and, as exhibited in analyses of Diane, Diphoso and Dintsho passages, suggests that modern socio-political solutions are required for linguistic problems. With such goals in mind, future language planners might succeed in rescuing African languages from the same incipient decline Plaatje warned about.

Η εργασία αφορά ένα ειδικό είδος κωδικοποίησης εντοπισμού και διόρθωσης λαθών, την κωδικοποίση Reed-Solomon. Οι κώδικες αυτού του είδους χρησιμοποιούνται σε τηλεπικοινωνιακές εφαρμογές (ενσύρματη τηλεφωνία, ψηφιακή τηλεόραση, ευρυζωνικές ασύρματες επικοινωνίες) και σε συστήματα ψηφιακής αποθήκευσης (οπτικοί, μαγνητικοί δίσκοι). Η κωδικοποίηση Reed-Solomon βασίζεται σε μία ειδική κατηγορία αριθμητικών πεδίων τα πεδία Galois (Galois Field). Στα πλαίσια της εργασίας πραγματοποιήθηκε μελέτη των ιδιοτήτων των πεδίων Galois. και σχεδιάστηκε κωδικοποιητής-αποκωδικοποιητής για κώδικες Reed Solomon. Η σχεδίαση υλοποιήθηκε σε υλικό (hardware) σε γλώσσα Verilog HDL. Η σύνθεση των κυκλωμάτων πραγματοποιήθηκε με τεχνολογία Πεδίων Προγραμματιζόμενων Πινάκων Πυλών (τεχνολογία FPGA) και τεχνολογία Ολοκληρωμένων Κυκλωμάτων Ειδικού Σκοπού (τεχνολογία ASIC). Ακολουθήθηκε η μεθοδολογία σχεδιασμού Μονάδων Διανοητικής Ιδιοκτησίας για ολοκληρωμένα κυκλώματα (IP core), σύμφωνα με την οποία η σχεδίαση είναι ανεξάρτητη της πλατφόμας υλοποίησης και μπορεί να υλοποιηθεί με καθόλου ή ελάχιστες αλλαγές σε διαφορετικές τεχνολογίες. Η έννοια των IP core βρίσκει ιδιαίτερη εφαρμογή σε Συστήματα σε Ολοκληρωμένα Κυκλώματα (System on Chip). / The present work is about a specific group of error detection and correction codes, the Reed-Solomon codes. Such codes are used in telecommunications applications (wire telephony, digital television, broadband wireless communications) and digital storage systems (optical, magnetic disks). The Reed Solomon codes are based on a specific category of numerical fields, called Galois Fields. The Work consists of the study of the properties of Galois fields and of the design of an codec for Reed Solomon codes. The design was implemented in hardware with the use of Verilog HDL language. The synthesis of the circuit targets Field programmable Gate Array (FPGA) and Applications Specific Integrated Circuit (ASIC) technologies. The design methodology for Intellectual Property Units for integrated circuits (IP cores) was used. According to that methodology the design is platform independent and consequently the implementation can be achieved with minimal or no changes in different technologies. The IP cores model is widely applied in Systems on Integrated Circuits (System on Chips).

Mass., Massachusetts Inst. of Technology, Diss.--Cambridge, 2001. / Literaturverz. S. [337] - 347.

Thesis (Ph. D.)--Københavns universitet, 1988. / Summary in Danish. Part 2 consists of Rennellese texts with parallel English translations. Some geneal. tables on folded leaves of plates in pt. 1. Includes indexes. Includes bibliographical references (pt. 1, p. 269-276).

Στην εργασία αυτή, μελετώνται διαφορετικοί αποκωδικοποιητές για κώδικες Reed-Solomon. Αφού γίνει μια εισαγωγή στο σύστημα επικοινωνίας, στα πεπερασμένα σώματα και στη θεωρία κωδίκων, παρουσιάζονται αλγόριθμοι που υλοποιούν αποκωδικοποιητές περιορισμένης απόστασης, λίστας και soft decoders. Συγκεκριμένα, μελετώνται κλασσικοί αποκωδικοποιητές, αποκωδικοποιητές βασισμένοι στον αλγόριθμο Guruswami-Sudan, και αποκωδικοποιητές βασισμένοι στον αλγόριθμο Koetter-Vardy. Η σύγκριση γίνεται ως προς τη διορθωτική ικανότητα και τη χρονική πολυπλοκότητα. Στα πλαίσια της εργασίας αυτής, σε συνέχεια της μελέτης υπαρχόντων αποκωδικοποιητών προτείνεται ένα είδος προσαρμοστικού αποκωδικοποιητή: φέρει την ίδια διορθωτική ικανότητα με έναν αποκωδικοποιητή λίστας, αλλά σε ορισμένες περιπτώσεις έχει ικανοποιητικά μικρότερη χρονική πολυπλοκότητα. Επίσης γίνεται μία ποιοτική διερεύνηση για το πότε πρέπει να προτιμάται ο προσαρμοστικός αποκωδικοποιητής. Προτείνονται δύο διαφορετικοί προσαρμοστικοί αποκωδικοποιητές. Η πρώτη εκδοχή, είναι μία διάταξη με δύο αποκωδικοποιητές. Αρχικά το ληφθέν διάνυσμα από το κανάλι, εισέρχεται ως είσοδος σε έναν κλασσικό αποκωδικοποιητή. Αν ο κλασσικός παρουσιάσει αδυναμία αποκωδικοποίησης, τότε επιχειρεί να διορθώσει το ίδιο διάνυσμα ένας αποκωδικοποιητής λίστας. Η δέυτερη εκδοχή, μοιάζει με την πρώτη, με τη διαφορά ότι ο δεύτερος αποκωδικοποιητής χρησιμοποιεί αποτελέσματα που έχουν ήδη υπολογιστεί από τον πρώτο, μειώνοντας έτσι την συνολική χρονική πολυπλοκότητα, σχετικά με την πρώτη εκδοχή. / In this thesis we study a family of linear block codes, the Reed-Solomon(RS) codes. RS codes are q-ary codes over some finite field GF(q). Therefore, they have strong burst-error correction capability, because they deal with groups of bits instead of single bits. Initially, we describe the employed communication system model, and introduce basic from finite field theory (construction and identities) and coding theory. After describing the RS encoding process, we describe different RS decoders (bounded distance decoder, list decoder and soft-input decoder). Specifically, in addition to traditional approaches, we focus on decoders based on Guruswami-Sudan and Koetter – Vardy algorithms. We compare them according to their complexity and performance, both in theory and experimentally. Furthermore, in this thesis, we propose an adaptive decoder, which has the same performance as a list decoder but in some cases it achieves much lower average time complexity. We present the experimental results, highlighting the cases where the adaptive decoder outperforms conventional decoders. The adaptive decoder comes in two different types. The first type is a system with two different decoders: the low complexity decoder attempts to decode a received vector and in case of decoding failure the subsequent decoder tries to decode the same received vector. The second type resembles the general organization of the above system; the second decoder re-uses intermediate results, previously computed by the first one.

Este trabalho investiga a decodificação turbo de códigos produto construídos a partir de códigos de Reed-Solomon sobre constelações QAM. Por meio da geometria euclidiana da constelação utilizada e das relações dos elementos de campo de Galois utilizados na codificação Reed-Solomon com os símbolos pertencentes ao alfabeto de modulação, é proposto um algoritmo de decodificação que utiliza a localização geométrica dos símbolos recebidos no processo de decodificação turbo. Tanto a primeira etapa da decodificação SISO baseada no algoritmo de Chase, como a extração da informação extrínseca baseada no algoritmo proposto por Pyndiah, são tratadas pelo uso de uma abordagem geométrica sobre o espaço euclidiano. Os resultados de simulação utilizando o algoritmo proposto coincidem com aqueles usando a decomposição e análise pragmática binária, sendo que a abordagem apresentada conduz a simplificações e otimizações em relação à metodologia binária no que ser refere à implementação dos possíveis esquemas de decodificação. / This work investigates the turbo decoding of product codes built using Reed- Solomon codes in QAM constellations. Using the euclidian geometry of the constellation and the relations of the Galois field elements used in the Reed-Solomon code and the modulation alphabet, a decoding algorithm for the turbo decoding process is proposed using the geometric localization of the received symbol. Both the first stage of the SISO decoding based on the Chase algorithm, as the calculation of the extrinsic information based on the Pyndiah algorithm, are treated using the geometric approach in the euclidian space. The simulations show that this algorithm gives similar performance results as the pragmatic binary decomposition approach, and leads to simplifications and optimizations in decoding implementations schemes compared to the former.

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