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
Rate 5/6 Trellis-Coded 8-PSK
TL;DR: Some new short constraint length codes are described for satellite channels which are constant-envelope and which have spectral and energy efficiencies intermediate to other recent coded techniques, namely r = 2/3 coded 8- PSK and r = 3/4 coded 16-PSK.
Journal ArticleDOI
Viterbi decoding of differentially encoded PSK signals transmitted over Rayleigh frequency-flat fading channels
TL;DR: Maximum Likelihood (bit) detection of differentially encoded M-PSK signals on Rayleigh fading channels is investigated and the solution can be related to previous results and leads to the implementation of a receiver structure based on the Viterbi algorithm and employing per-survivor processing.
Patent
Coding and modulation method and apparatus for its implementation
TL;DR: In this paper, the authors describe the steps of encoding digital information in a Hybrid Concatenated Code encoder (501), mapping the encoded digital information into multiple-valued symbols in a Multi-Level Coding encoder(511, 512a-d, 513, 514), transmitting the multiplevalued symbols, receiving the multiple value symbols, and decoding the received multiple-value symbols in the Multi-Stage Decoder (800) are employed.
Proceedings ArticleDOI
Reduced-state sequence estimation for trellis-coded modulation on intersymbol interference channels
TL;DR: The authors consider the detection of trellis codes designed for ideal channels when they operate in the presence of intersymbol interference (ISI) and describe a well-structured reduced-state sequence-estimation algorithm which can achieve the performance of maximum-likelihood sequence estimation (MLSE) at drastically reduced complexity.
Journal ArticleDOI
Achievable Information Rates for Fiber Optics: Applications and Computations
TL;DR: It is shown that AIRs such as the mutual information and generalized mutual information are good design metrics for coded optical systems and the theoretical predictions are compared to the performance of modern codes including low-parity density check and polar codes.
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.
Book
Principles of Communication Engineering
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.