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
Low-Complexity Iterative Receiver Structure for Time-Varying Frequency-Selective Shallow Underwater Acoustic Channels Using BICM-ID: Design and Experimental Results
TL;DR: Although the proposed convolutional BICM-ID receiver matches approximately the performance of turbo-BICM, it exhibits lower implementation complexity and reduced memory requirements, attributes that are attractive for robust high data-rate underwater acoustic modems.
Journal ArticleDOI
Polar quantizing for coded PSK transmission
R.D. Parsons,S.G. Wilson +1 more
TL;DR: The issue of demodulator quantization prior to decoding in error control systems employing M-ary phase-shift keying (PSK) as a modulation technique is considered, and the use of angle-only, or polar, quantization with J>or=M levels, which is an easily implemented alternative to rectangular quantization, is described.
Journal ArticleDOI
Optimal detection of coded differentially encoded QAM and PSK signals with diversity reception in correlated fast Rician fading channels
TL;DR: The optimal sequence estimator for digital signals received over Lambda different channels is derived and it is shown that for the lth channel, the transmitted signal is corrupted by a mixture of additive white Gaussian noise and frequency-nonselective, correlated, fast Rician fading.
Proceedings ArticleDOI
Superposition Coding with Peak-Power Limitation
TL;DR: A low-complexity soft compensation algorithm (SCA) for combating the clipping effect is investigated and it can be easily combined with soft-input soft-output (SISO) decoding algorithms in an iterative manner.
Proceedings ArticleDOI
Advantages of uniform scalar dead-zone quantization in image coding system
TL;DR: It is shown that if the dead-zone is designed carefully, USDZQ can effectively reduce the output bits of the entropy coder, although it reduces quantization precision by discarding some data around zero, which is suitable for a transform based image compression system.
References
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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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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.