Sökning: "BCJR algorithm"

Visar resultat 6 - 8 av 8 avhandlingar innehållade orden BCJR algorithm.

  1. 6. Turbo Codes and Channel Estimation in Wireless Systems

    Författare :Bartosz Mielczarek; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; adaptive coding; turbo codes; PSAM; timing offset; BCJR algorithm; synchronization; channel estimation; phase offset; Wiener filters; unequal error protection; OFDM;

    Sammanfattning : This thesis focuses on practical implementation issues of turbo codes with imperfectly estimated fading wireless channels and limited code length. Channel estimation can be divided into estimation of static parameters, such as constant timing and phase offset, and dynamic parameters, such as fading channel amplitudes. LÄS MER

  2. 7. Joint Source-Channel Coding using Trellis Coded CPM

    Författare :Zihuai Lin; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; iterative decoding; serially concatenated CPM; punctured ring convolutional codes.; trellis coded quantization; turbo codes; turbo trellis coded modulation; soft decoding; ring convolutional coded CPM; continuous phase modulation; Joint source channel coding;

    Sammanfattning : The thesis investigates Joint Source and Channel Coding(JSCC) using combined Trellis Coded Quantization (TCQ) and coded modulation. First we investigate a JSCC scheme using combined TCQ/Trellis Coded CPM (TCQ/TCCPM). Based on the BCJR algorithm for trellis coded CPM, we derive an optimal soft decoding algorithm for the considered systems. LÄS MER

  3. 8. On Woven Convolutional Codes

    Författare :Stefan Höst; Institutionen för elektro- och informationsteknik; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER