Sökning: "turbo-codes"

Visar resultat 1 - 5 av 22 avhandlingar innehållade ordet turbo-codes.

1. 1. 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. 2. 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

4. 3. Synchronization in Turbo Coded Systems

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

   Sammanfattning : 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. LÄS MER

5. 4. On the Design of Error Control Coding for Wireless Communication Systems

   Författare :Carl Fredrik Leanderson; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; joint source-channel decoding; Electrical engineering; Elektroteknik; a posteriori probability; soft decoding; list sequence decoding; incremental redundancy; retransmission; low-rate; parallel concatenated; convolutional codes; Turbo codes; Wireless; error correction;

   Sammanfattning : New wireless services such as mobile Internet, multimedia streaming and high speed packet data access are making their way to the market. Availability of low-cost equipment providing high transmission quality and efficient spectrum utilization is crucial to the success of these services. LÄS MER

7. 5. On the Construction and Analysis of Iteratively Decodable Codes

   Författare :Dmitri Truhachev; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Computer science; minimum distance; cycles; asymptotic performance; turbo codes; iterative decoding; low-density parity-check codes; numerical analysis; systems; control; Datalogi; numerisk analys; system; kontroll;

   Sammanfattning : Iterative decoding methods allow efficient decoding of long codes that are composed of smaller component codes. As a result reliable communication can be achieved with low decoding complexity even for rates close to Shannon capacity. This makes iteratively decodable codes a very attractive object of study in modern coding theory. LÄS MER