Search for dissertations about: "turbo code"

Showing result 1 - 5 of 25 swedish dissertations containing the words turbo code.

2. 1. Towards a Theory of Codes for Iterative Decoding

   Author : Michael Lentmaier; Institutionen för elektro- och informationsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bit error probability; low-density parity-check convolutional code; low-density parity-check code; turbo code; convolutional code; channel coding; iterative decoding; Informatics; systems theory; Informatik; systemteori;

   Abstract : Channel codes in combination with iterative decoding techniques are a both powerful and efficient method to protect data against disturbances in digital communication systems. This thesis deals with various code constructions for block-wise and continuous transmission that have the potential to achieve low bit error rates with iterative decoding, even when operating close to the Shannon limit. READ MORE

4. 2. Synchronization in Turbo Coded Systems

   Author : Bartosz Mielczarek; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; timing offset; Turbo codes; synchronization; maximum a-posteriori estimation; phase offset; BCJR algorithm.; maximum likelihood estimation;

   Abstract : Turbo codes and their unusual properties have attracted significant attentionof the information theory community. There already exist many articlesand papers devoted to the theory of these codes. This thesis, however,focuses on practical implementation issues of turbo codes, with synchronizationproblems as the main topic. READ MORE

5. 3. On the Design of Turbo Codes

   Author : Johan Hokfelt; Institutionen för elektro- och informationsteknik; []
   Keywords : 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;

   Abstract : 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. READ MORE

6. 4. 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

7. 5. Turbo Codes and Channel Estimation in Wireless Systems

   Author : Bartosz Mielczarek; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. READ MORE