Journal ArticleDOI
Channel coding with multilevel/phase signals
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TLDR
A coding technique is described which improves error performance of synchronous data links without sacrificing data rate or requiring more bandwidth by channel coding with expanded sets of multilevel/phase signals in a manner which increases free Euclidean distance.Abstract:
A coding technique is described which improves error performance of synchronous data links without sacrificing data rate or requiring more bandwidth. This is achieved by channel coding with expanded sets of multilevel/phase signals in a manner which increases free Euclidean distance. Soft maximum--likelihood (ML) decoding using the Viterbi algorithm is assumed. Following a discussion of channel capacity, simple hand-designed trellis codes are presented for 8 phase-shift keying (PSK) and 16 quadrature amplitude-shift keying (QASK) modulation. These simple codes achieve coding gains in the order of 3-4 dB. It is then shown that the codes can be interpreted as binary convolutional codes with a mapping of coded bits into channel signals, which we call "mapping by set partitioning." Based on a new distance measure between binary code sequences which efficiently lower-bounds the Euclidean distance between the corresponding channel signal sequences, a search procedure for more powerful codes is developed. Codes with coding gains up to 6 dB are obtained for a variety of multilevel/phase modulation schemes. Simulation results are presented and an example of carrier-phase tracking is discussed.read more
Citations
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Journal ArticleDOI
Coded modulation for noncoherent reception with application to OFDM
TL;DR: A design for multilevel coding schemes to approach theoretical limits for power- and bandwidth-efficient noncoherent transmission over the equivalent fading channel and it is shown that bit-interleaved coded modulation, which relies on Gray labeling, is competitive only in the case of conventional differential detection with N=2.
Proceedings ArticleDOI
Entropy-constrained trellis coded quantization
Thomas R. Fischer,M. Wang +1 more
TL;DR: Improved encoding performance is shown by simulation based on trellises generated by rate-1/2 convolutional encoding circuits, where the formulation reserves one bit/branch to specify the path through the trellis, and thetrellis branch codewords are encoded with a suitable entropy code.
Patent
Viterbi slicer for turbo codes
TL;DR: In this article, a Viterbi decoder with zero traceback (i.e., one which does not consider future values of the signal only past values) is used to predict what the incoming signal is.
New space-time coding techniques with bit interleaved coded modulations
TL;DR: The channel inter-leaver is the fundamental part of the bit-interleaved coded modulation calling the shots about the achieved diversity, and full diversity and quasi-optimal coding gains are observed for a given error correcting code.
Patent
Symbol encoding and decoding architecture for trellis-coded modulation in gigabit ethernet
TL;DR: This paper proposed a method of encoding a plural-bit data word as a plurality of multi-level symbols, where each of the plurality of multilevel symbols has a value selected from a predetermined plurality of levels.
References
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Book
Information Theory and Reliable Communication
TL;DR: This chapter discusses Coding for Discrete Sources, Techniques for Coding and Decoding, and Source Coding with a Fidelity Criterion.
Journal ArticleDOI
The viterbi algorithm
TL;DR: This paper gives a tutorial exposition of the Viterbi algorithm and of how it is implemented and analyzed, and increasing use of the algorithm in a widening variety of areas is foreseen.
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I. M. Jacobs,J. M. Wozencraft +1 more
TL;DR: Textbook on communication engineering emphasizing random processes, information and detection theory, statistical communication theory, applications, etc.
Journal ArticleDOI
Convolutional codes I: Algebraic structure
TL;DR: Minimal encoders are shown to be immune to catastrophic error propagation and, in fact, to lead in a certain sense to the shortest decoded error sequences possible per error event.
Journal ArticleDOI
Coherent and Noncoherent Detection CPFSK
W. Osborne,M. Luntz +1 more
TL;DR: This work provides a complete analysis of the performance of CPFSK at high SNR as well as low SNR and thereby unifies and extends the results previously available.