Sökning: "Maximum-Likelihood Decoding"

Visar resultat 11 - 15 av 20 avhandlingar innehållade orden Maximum-Likelihood Decoding.

1. 11. 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. 12. 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

4. 13. On Probabilistic Shaping and Learned Decoders with Application to Fiber-Optic Communications

   Författare :Andreas Buchberger; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Error correcting codes; learned decoders; machine learning; iterative decoding; probabilistic shaping; fiber-optic communications; pruning;

   Sammanfattning : We live in an ubiquitously connected world whose backbone are optical fibers. Achieving high spectral efficiencies and hence high transmission rates requires a careful combination of forward error correction (FEC) and higher-order modulation. This is referred to as coded modulation. LÄS MER

5. 14. Analysis of Some Convolutional Coding Constructions

   Författare :Karin Engdahl; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbo-codes; low-density parity-check convolutional codes; low-density codes; PSK; PAM; QAM; coded modulation; multilevel coding; convolutional codes; multilevel modulation; iterative decoding; Informatics; systems theory; Informatik; systemteori;

   Sammanfattning : This thesis focuses on different convolutional coding constructions for digital communication systems, and on methods to analyze these constructions. The work presented in the thesis can be divided into three main areas; error probability bounds for convolutional codes, analysis of multilevel modulation, and investigation of low-density parity-check convolutional codes. LÄS MER

7. 15. Iterative Detection, Decoding and Channel Parameter Estimation for Orthogonally Modulated DS-CDMA Systems

   Författare :Pei Xiao; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : In this thesis, we study iterative detection, decoding and channel parameter estimation algorithms for asynchronous direct-sequence code division multiple access (DS-CDMA) systems employing orthogonal signalling formats and long scrambling codes. Multiuser detection techniques are widely used to combat the detrimental effects of multipath fading and multiple access interference (MAI), which are the major impairments in CDMA communication systems. LÄS MER