Journal ArticleDOI
Channel coding with multilevel/phase signals
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
On Limits of Wireless Communications in a Fading Environment when UsingMultiple Antennas
G. J. Foschini,M. J. Gans +1 more
TL;DR: In this article, the authors examined the performance of using multi-element array (MEA) technology to improve the bit-rate of digital wireless communications and showed that with high probability extraordinary capacity is available.
Journal ArticleDOI
Space-time codes for high data rate wireless communication: performance criterion and code construction
TL;DR: In this paper, the authors consider the design of channel codes for improving the data rate and/or the reliability of communications over fading channels using multiple transmit antennas and derive performance criteria for designing such codes under the assumption that the fading is slow and frequency nonselective.
Journal ArticleDOI
Near optimum error correcting coding and decoding: turbo-codes
Claude Berrou,A. Glavieux +1 more
TL;DR: A new family of convolutional codes, nicknamed turbo-codes, built from a particular concatenation of two recursive systematic codes, linked together by nonuniform interleaving appears to be close to the theoretical limit predicted by Shannon.
Journal ArticleDOI
Analysis and Simulation of a Digital Mobile Channel Using Orthogonal Frequency Division Multiplexing
TL;DR: The analysis and simulation of a technique for combating the effects of multipath propagation and cochannel interference on a narrow-band digital mobile channel using the discrete Fourier transform to orthogonally frequency multiplex many narrow subchannels, each signaling at a very low rate, into one high-rate channel is discussed.
References
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Journal ArticleDOI
Error bounds for multi-h phase codes (Corresp.)
TL;DR: Upper and lower bounds for the probability of a decoding error event and for symbol error probability are developed for the class of time-varying phase codes known as multi- h codes.
Journal ArticleDOI
On Improving Bit Error Probability of QPSK and 4-Level Amplitude Modulation Systems by Convolutional Coding
TL;DR: It is shown that the saving in average power signal-signal-to-noise ratio over that required for an uncoded system with the same channel symbol rate was more than 2 dB with PSK and APK, and 1.5 dB with AM.
Proceedings Article
Simulated error performance of multi-h phase codes
TL;DR: Multi- h phase coded signals are constant-envelope sinusoids whose phase varies in a piecewise linear manner driven by cyclically chosen slopes, and the transmission over a Gaussian noise channel with Viterbi decoder is simulated.