Sökning: "convolutional codes"

Visar resultat 6 - 10 av 47 avhandlingar innehållade orden convolutional codes.

  1. 6. Analysis of Some Convolutional Coding Constructions

    Författare :Karin Engdahl; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbo-codes; low-density parity-check convolutional codes; low-density codes; PSK; PAM; QAM; coded modulation; multilevel coding; convolutional codes; multilevel modulation; iterative decoding; Informatics; systems theory; Informatik; systemteori;

    Sammanfattning : This thesis focuses on different convolutional coding constructions for digital communication systems, and on methods to analyze these constructions. The work presented in the thesis can be divided into three main areas; error probability bounds for convolutional codes, analysis of multilevel modulation, and investigation of low-density parity-check convolutional codes. LÄS MER

  2. 7. On the Design of Turbo Codes

    Författare :Johan Hokfelt; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Channel coding; concatenated codes; convolutional codes; iterative decoding; interleaver design; trellis termination; Electronics; Turbo codes; Elektronik;

    Sammanfattning : This thesis is about Turbo codes - codes constructed via parallel concatenation of two recursive convolutional encoders linked by an interleaver. The focus of the work is on the understanding and design of Turbo codes. LÄS MER

  3. 8. An Encounter with Convolutional Codes over Rings

    Författare :Emma Wittenmark; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Telekommunikationsteknik; Data- och systemvetenskap; Telecommunication engineering; computer technology; direct sum decomposition of a ring; Systems engineering; minimal trellis; generator matrix properties; code properties; convolutional codes; codes over rings;

    Sammanfattning : Convolutional codes is one possibility when there is a need for error-correcting codes in communication systems. Using convolutional codes over rings is a relatively new approach. LÄS MER

  4. 9. Multirate Codes and Multicarrier Modulation for Future Communication Systems

    Författare :Pål Frenger; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; channel estimation; code-spread CDMA; DS-CDMA; convolutional codes; interference cancellation; nested convolutional codes; multicarrier modulation; optimum distance spectrum ODS ; rate-compatible punctured convolutional codes RCPC-codes ; OFDM; turbo decoding; rate matching; parallel combinatory signaling; Rayleigh fading;

    Sammanfattning : In this thesis, new detection and modulation methods for multicarrier systems are presented. The proposed multicarrier detectors are based on feedback of previously detected symbols and the idea is to exploit the correlation, both in time between consecutive symbols, and in frequency between neighboring sub-carriers. LÄS MER

  5. 10. Capabilities of Convolutional Codes: Unequal Error Protection and More

    Författare :Victor Pavlushkov; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Elektronik och elektroteknik; Electronics and Electrical technology; systemteori; Informatik; Informatics; systems theory; woven codes; unequal error protection; active input-distance; active output-distance; maximum slope; active distances; Convolutional codes; error-correcting capability;

    Sammanfattning : Many communication systems obtain enhanced performance by using concatenated coding schemes. Turbo codes and woven convolutional codes are two examples of such schemes. LÄS MER