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Showing result 1 - 5 of 47 swedish dissertations matching the above criteria.

  1. 1. On Woven Convolutional Codes

    Author : Stefan Höst; Institutionen för elektro- och informationsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Automation; iterative decoding; woven convolutional code; cascaded convolutional code; free distance; convolutional code; active distance; robotics; control engineering; Automatiska system; robotteknik; reglerteknik;

    Abstract : Concatenation of several conventional convolutional encoders is a both powerful and practical method to obtain encoding schemes that are attractive for use in communication systems where very low error probabilities are needed. This thesis is devoted to woven convolutional codes, a construction where the constituent codes are woven together in a manner that resembles the structure of a fabric. READ MORE

  2. 2. Iteratively Decodable Convolutional Codes: Analysis and Implementation Aspects

    Author : Alberto Jimenez Feltström; Institutionen för elektro- och informationsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; systems theory; Informatics; Intersymbol Interference; BPSK; Product Codes; Braided Codes; Low-Density Parity-Check Codes; Convolutional Codes; Iterative Decoding; Informatik; systemteori; Systems engineering; computer technology; Data- och systemvetenskap;

    Abstract : This thesis addresses the theory and implementation aspects of iteratively decodable codes. Iteratively decodable codes include, in particular, Gallager's regular low-density parity-check (LDPC) codes, Tanner's generalized LDPC (GLDPC) codes, turbo codes due to Berrou et. al. and expander codes. READ MORE

  3. 3. Sparse Codes on Graphs with Convolutional Code Constraints

    Author : Muhammad Umar Farooq; Kommunikationsteknologi; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Braided codes; Density evolution; Serially concatenated codes; Spatially coupled codes; Generalized LDPC codes; threshold saturation; Turbo codes;

    Abstract : Modern coding theory is based on the foundation of the sparse codes on graphs, such as the low-density parity-check (LDPC) codes, and the turbo-like codes (TCs) with component convolutional codes. The success of the LDPC codes and the TCs lies in their ability to perform low-complexity iterative message passing decoding procedures. READ MORE

  4. 4. Codes on Graphs and More

    Author : Florian Hug; Institutionen för elektro- och informationsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; convolutional codes; woven graph codes; Low-density parity-check LDPC codes; tailbiting codes; bit error probability; MacWilliams Identity;

    Abstract : Modern communication systems strive to achieve reliable and efficient information transmission and storage with affordable complexity. Hence, efficient low-complexity channel codes providing low probabilities for erroneous receptions are needed. READ MORE

  5. 5. On Tailbiting Codes from Convolutional Codes

    Author : Per Ståhl; Institutionen för elektro- och informationsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; computer technology; Systems engineering; Teknik; Technological sciences; encoder inverse; systematic feedback encoder; state complexity; trellis; tailbiting termination method; tailbiting code; channel coding; convolutional code; Data- och systemvetenskap; Informatics; systems theory; Informatik; systemteori;

    Abstract : Tailbiting is a method to terminate convolutional codes into block codes. We call these block codes tailbiting codes. This thesis focuses on the encoding of tailbiting codes. The tailbiting method is carefully investigated. READ MORE