A5077846751- Error Correcting Code Techniques
- Advanced Wireless Communication Techniques
- Cooperative Communication and Network Coding
- Coding theory and cryptography
- Optical Network Technologies
- Advanced Photonic Communication Systems
- Cellular Automata and Applications
- Wireless Communication Security Techniques
- graph theory and CDMA systems
- Full-Duplex Wireless Communications
- Advanced Wireless Communication Technologies
- DNA and Biological Computing
- Advanced Fiber Laser Technologies
- Algorithms and Data Compression
- Semiconductor Lasers and Optical Devices
- Optical Wireless Communication Technologies
- Photonic and Optical Devices
- Neural Networks and Reservoir Computing
- Advanced MIMO Systems Optimization
- Quantum Computing Algorithms and Architecture
- Advanced Data Storage Technologies
- Advanced Wireless Network Optimization
- PAPR reduction in OFDM
- Wireless Communication Networks Research
- Power Line Communications and Noise
University of Toronto
2016-2025
Rogers (United States)
2019-2023
New York University
2018
Cornell University
2018
University of Maryland, College Park
2018
Monash University
2018
Institute of Electrical and Electronics Engineers
2018
McGill University
2015
Technical University of Munich
2015
Institute for Advanced Study
2015
Algorithms that must deal with complicated global functions of many variables often exploit the manner in which given factor as a product "local" functions, each depends on subset variables. Such factorization can be visualized bipartite graph we call graph, In this tutorial paper, present generic message-passing algorithm, sum-product operates graph. Following single, simple computational rule, algorithm computes-either exactly or approximately-various marginal derived from function. A wide...
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The problem of error-control in random linear network coding is considered. A "noncoherent" or "channel oblivious" model assumed where neither transmitter nor receiver to have knowledge the channel transfer characteristic. Motivated by property that vector-space preserving, information transmission modeled as injection into a basis for vector space <emphasis><formula...
The problem of error control in random linear network coding is addressed from a matrix perspective that closely related to the subspace K\"otter and Kschischang. A large class constant-dimension codes investigated. It shown this can be easily constructed rank-metric codes, while preserving their distance properties. Moreover, it minimum decoding such reformulated as generalized for where partial information about available. This may form erasures (knowledge an location but not its value)...
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The message-passing approach to model-based signal processing is developed with a focus on Gaussian message passing in linear state-space models, which includes recursive least squares, minimum-mean-squared-error estimation, and Kalman filtering algorithms. Tabulated computation rules for the building blocks of models allow us compose variety such algorithms without additional derivations or...
Quantum Communication is the art of transferring an unknown quantum state from one location, Alice, to a distant one, Bob. This non-trivial task because no-cloning theorem which prevents merely using only classical means.
Variable-rate data transmission schemes in which constellation points are selected according to a nonuniform probability distribution studied. When the criterion is one of minimizing average transmitted energy for given bit rate, best possible with select constellations Maxwell-Boltzmann distribution. In principle, when distribution, ultimate shaping gain ( pi e/6 or 1.53 dB) can be achieved any dimension. Nonuniform signaling designed by mapping simple variable-length prefix codes onto...
A modification is introduced of the successive-cancellation decoder for polar codes, in which local decoders rate-one constituent codes are simplified. This reduces decoding latency and algorithmic complexity conventional decoder, while preserving bit block error rate. Significant reductions achieved over a wide range code rates.
Staircase codes, a new class of forward-error-correction (FEC) codes suitable for high-speed optical communications, are introduced. An ITU-T G.709-compatible staircase code with rate R=239/255 is proposed, and FPGA-based simulation results presented, exhibiting net coding gain (NCG) 9.41 dB at an output error 1E-15, improvement 0.42 relative to the best from G.975.1 recommendation. floor analysis technique proposed shown have 4.0E-21.
In this paper, numerical methods are suggested to compute the discrete and continuous spectrum of a signal with respect Zakharov-Shabat system, Lax operator underlying numerous integrable communication channels including nonlinear Schrödinger channel, modeling pulse propagation in optical fibers. These subsequently tested their ability estimate compared against each other. used various signals commonly fiber communications. It is found that layer-peeling spectral suitable schemes spectra...
The problem of designing new physical-layer network coding (PNC) schemes via lattice partitions is considered. Building on a recent work by Nazer and Gastpar, who demonstrated its asymptotic gain using information-theoretic tools, we take an algebraic approach to show potential in non-asymptotic settings. We first relate Nazer-Gastpar's the fundamental theorem finitely generated modules over principle ideal domain. Based this connection, generalize their code construction simplify encoding...
We design staircase codes with overheads between 6.25% and 33.3% for high-speed optical transport networks. Using a reduced-complexity simulation of coded transmission over the BSC, we select code candidates from within limited parameter space. Software simulations BSC are performed algebraic component decoders. The net coding gain best designs competitive known hard-decision decodable entire range overheads. At 20% overhead, 0.92 dB capacity at bit error-rate <inline-formula...
The nonlinear Fourier transform (NFT), a powerful tool in soliton theory and exactly solvable models, is method for solving integrable partial differential equations governing wave propagation certain media. NFT decorrelates signal degrees-of-freedom such much the same way that does linear systems. In this three-part series of papers, observation exploited data transmission over channels as optical fibers, where pulse governed by Schr\"odinger equation. scheme, which can be viewed analogue...
We present a unified graphical model framework for describing compound codes and deriving iterative decoding algorithms. After reviewing variety of models (Markov random fields, Tanner graphs, Bayesian networks), we derive general distributed marginalization algorithm functions described by factor graphs. From this algorithm, Pearl's (1986) belief propagation is easily derived as special case. point out that algorithms various codes, including "turbo decoding" parallel-concatenated...
Abstract In‐building power lines have often been considered as attractive media for high‐speed data transmission, particularly applications like home networking. In this paper, we develop models line channels based both on theoretical considerations and practical measurements. We consider channel frequency response noise in the 1–30 MHz band propose a number of test which to measure performance modems. Copyright © 2003 John Wiley & Sons, Ltd.
A conditionally Gaussian channel is a vector in which the output, given input, has distribution with (well-behaved) input-dependent mean and covariance. We study capacity-achieving probability measure for channels subject to bounded-input constraints average cost constraints. Many practical communication systems, including additive noise channels, certain optical fading interference fall within this framework. Subject constraint (and constraints), we show that capacity achievable derive...
The problem of minimizing the vertex count at a given time index in trellis for general (nonlinear) code is shown to be NP-complete. Examples are provided that show (1) minimal nonlinear may not observable, i.e. some codewords represented by more than one path through and (2) incompatible with another index. A produce defined used construct trellises sum codes. Minimal linear codes obtained forming product elementary corresponding one-dimensional subcodes generated atomic codewords....
The problem of securing a network coding communication system against an eavesdropper adversary is considered. implements linear to deliver n packets from source each receiver, and the can eavesdrop on \mu arbitrarily chosen links. objective provide reliable all receivers, while guaranteeing that information remains information-theoretically secure adversary. A scheme proposed achieve maximum possible rate n-\mu packets. scheme, which based rank-metric codes, has distinctive property being...
The problem of error correction in both coherent and noncoherent network coding is considered under an adversarial model. For coding, where knowledge the topology code assumed at source destination nodes, capability (outer) succinctly described by rank metric; as a consequence, it shown that universal correcting codes achieving Singleton bound can be easily constructed efficiently decoded. not assumed, (subspace) given exactly new metric, called injection which closely related to, but...
This paper reviews digital signal processing techniques that compensate, mitigate, and exploit fiber nonlinearities in coherent optical transmission systems.
We experimentally demonstrate the successful modulation and error-free detection of three eigenvalue nonlinear frequency division multiplexed (NFDM) signals over 1800 km based on recently developed Fourier transform theoretical framework with digital coherent receivers. The eigenvalues are located upper-half complex plane modulated by independent ON-OFF keying signals, thus forming 3-bit NFDM symbols for fiber transmissions.
Motivated by the looming "capacity crunch" in fiber-optic networks, information transmission over such systems is revisited. Among numerous distortions, inter-channel interference multiuser wavelength-division multiplexing (WDM) identified as seemingly intractable factor limiting achievable rate at high launch power. However, this distortion and similar ones arising from nonlinearity are primarily due to use of methods suited for linear systems, namely WDM pulse-train transmission, nonlinear...
This work proposes a probabilistic shaping scheme for optical WDM systems, where nonlinear interference noise depends on the input signal power distribution. With 16-QAM, white Gaussian channel analysis shows that shaped constellation is able to achieve reach improvement of up 7%, while split-step Fourier method simulations suggest even higher gains are possible in practice. An example system developed transmission distance around 3280 km. A mapping and low-density parity-check code this...
Locally repairable codes (LRCs) are considered with equal or unequal localities, local distances, and field sizes. An explicit two-layer architecture a sum-rank outer code is obtained, having disjoint groups achieving maximal recoverability (MR) for all families of linear (MDS not) simultaneously, up to specified maximum locality <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$r $...
Abstract The Covid-19 pandemic showed forcefully the fundamental importance broadband data communication and internet has in our society. Optical communications forms undisputable backbone of this critical infrastructure, it is supported by an interdisciplinary research community striving to improve develop further. Since first ‘Roadmap optical communications’ was published 2016, field seen significant progress all areas, time ripe for update status. area become increasingly diverse,...
This paper introduces the pixelated wireless optical channel, which transmits data at high rates using a series of coded time-varying images. multiple-input/multiple-output point-to-point channel uses arrays intensity transmitters and detectors to exploit inherent spatial degrees freedom realize significant gains in spectral efficiency over single-element systems. Spatial discrete multitone modulation is introduced as means combat low-pass distortion alleviate alignment problems previous The...