Sökning: "concatenation"

Visar resultat 6 - 10 av 22 avhandlingar innehållade ordet concatenation.

  1. 6. Semigroups, multisemigroups and representations

    Författare :Love Forsberg; Volodymyr Mazorchuk; Ernst Dieterich; Stuart Margolis; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; representation theory; semigroups; multisemigroups; category theory; 2-categories;

    Sammanfattning : This thesis consists of four papers about the intersection between semigroup theory, category theory and representation theory. We say that a representation of a semigroup by a matrix semigroup is effective if it is injective and define the effective dimension of a semigroup S as the minimal n such that S has an effective representation by square matrices of size n. LÄS MER

  3. 7. Coding Strategies for Compress-and-Forward Relaying

    Författare :Ricardo Blasco-Serrano; Mikael Skoglund; Ragnar Thobaben; Joerg Kliewer; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Telecommunication theory; Telekommunikationsteori;

    Sammanfattning : The deployment of large communication networks with many autonomous devices has opened new possibilities for transmission. In particular cooperation among the different nodes has been identified as an enabling technology to satisfy the increasing demand of resources. LÄS MER

  4. 8. 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

  5. 9. On Boolean Functions in Symmetric-Key Ciphers

    Författare :Enes Pasalic; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; autocorrelation properties; correlation attacks; nonlinearity; resiliency; Boolean function; Stream ciphers; block ciphers; Informatics; systems theory; Informatik; systemteori;

    Sammanfattning : This thesis discusses new results on the design and the existence of cryptographically strong Boolean functions used in the design of stream and block ciphers. By interlinking theoretical results and computer search some open problems have been solved, that is, we have shown the existence of previously unknown classes of functions. LÄS MER

  7. 10. On distributed coding for relay channels

    Författare :Zhongwei Si; Mikael Skoglund; Ragnar Thobaben; Alexandre Graell i Amat; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Telecommunication; Telekommunikation;

    Sammanfattning : Cooperative transmission is considered to be a key-technique for increasing the robustness, the efficiency, or the coverage of wireless communication networks. The basic concept is that the information transmission from a sender to a receiver can be aided by one or several relay nodes in a cooperative manner under constraints on power, complexity or delay. LÄS MER