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Optical Hexadecimal coding/decoding Using 16-QAM Signal and FWM in HNLFs

JOURNAL OF LIGHTWAVE TECHNOLOGY 2012年第17期30卷 2890-2900页

作者： Wang, Jian Yang, Jeng-Yuan Wu, Xiaoxia Willner, Alan E. Huazhong Univ Sci & Technol Wuhan Natl Lab Optoelect Coll Optoelect Sci & Engn Wuhan 430074 Peoples R China Univ So Calif Ming Hsieh Dept Elect Engn Los Angeles CA 90089 USA

We propose a simple approach to manipulating the constellation of a multilevel modulation signal in the optical domain. By exploiting degenerate four-wave mixing (FWM) in highly nonlinear fibers and adopting 16-ary quadrature amplitude modulation (16-QAM) signal, we demonstrate 10-Gbaud/s optical variable symbol-wise hexadecimal coding/decoding assisted by a continuous-wave (CW) pump or a phase-modulated pump. The former takes the coding through the phase conjugation of degenerate FWM, and the latter offers enhanced coding via the combined contributions from the phase modulation of the pump and the phase-conjugated FWM. The penalty of optical signal-to-noise ratio for coding/decoding is measured to be <1.1 dB with a CW pump and <1.2 dB with a (0, pi/4) phase-modulated pump at a bit-error rate of 2e-3 (enhanced forward error correction threshold). The dependence of coding/decoding performance on the phase modulation depth of the pump and the signal/pump misalignment is also investigated. Moreover, considering that a hexadecimal number denotes four binary numbers, we develop the symbol-wise hexadecimal coding/decoding to general binary coding/decoding, i.e., 10-Gbaud/s symbol-wise hexadecimal coding/decoding is accompanied by 40-Gbit/s binary coding/decoding.

关键词： coding/decoding four-wave mixing (FWM) highly nonlinear fiber (HNLF) quadrature amplitude modulation (QAM)

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Research Progress of Structured Light coding/decoding Communications

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ACTA OPTICA SINICA 2019年第1期39卷

作者： Wang Jian Liu Jun Zhao Yifan Huazhong Univ Sci & Technol Wuhan Natl Lab Optoelect Wuhan 430074 Hubei Peoples R China Huazhong Univ Sci & Technol Sch Opt & Elect Informat Wuhan 430074 Hubei Peoples R China

Structured light fields arc a kind of special light fields that have tailored lightwave spatial structure. The generalized structured light fields arc these kinds of fields including spatially variant amplitude, phase and polarization distribution as well as space array. Structured light fields have seen wide applications in optical manipulation, microscopy, imaging, metrology, sensing, nonlinear optics, astronomy, quantum science and optical communications owing to their distinct advantages. Structured light communication techniques include multiplexing communications and coding/decoding communications. In this review article, the recent progress of structured light coding/decoding communications is retrospected. Various generation methods of structured light fields and structured light coding/decoding communications with different spatial modes (orbital angular momentum mode, non -diffraction Bessel mode, linearly polarized mode, vector mode, space array), different coding methods (direct mode coding, high-speed mapping), and different scenarios (photonic chip, free space, fiber) arc comprehensively reviewed. Future trend and perspective arc also discussed. Structured light coding/decoding communications exploit the space domain dimensional resources of light fields, which provide a potential solution to address the new capacity crunch of optical communications and enable sustainable expansion of optical communications.

关键词： physical optics optical communications coding/decoding space domain structured light field orbital angular momentum vector light field

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Demonstration of a Visible-Light Parallel Communication Link Based on Hexadecimal Vector Beam Array coding/decoding 16

Demonstration of a Visible-Light Parallel Communication Link...

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16th International Conference on Optical Communications and Networks (ICOCN)

作者： Zhao, Yifan Li, Shuhui Du, Jing Wang, Jian Huazhong Univ Sci & Technol Sch Opt & Elect Informat Wuhan Natl Lab Optoelect Wuhan 430074 Hubei Peoples R China

ISBN: (纸本)9781538632734

We experimentally demonstrate visible-light coding/decoding utilizing hexadecimal vector beam array for parallel communication link. The hexadecimal base mode is investigated and 128-my is also available. We present vector beam array carrying 4x6/6x8/12x16 hexadecimal numbers and error-free data stream transmission performance is also demonstrated.

关键词： coding/decoding Vector beam array

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A PROGRAM NUCLEUS FOR ENcoding AND decoding CALENDAR DATES

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COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 1986年第3期23卷 317-318页

作者： SINN, HP UNIV HOSP MARBURG DEPT PATHOL MARBURG FED REP GER

A novel algorithm and subroutine is presented for encoding and decoding calendar dates. For encoding a numeric calendar date in the form day, month, year is converted into an integer variable in the range between 215-1 and -215. With decoding this integer variable is converted into numeric day, month and year. The algorithm performs very quickly and takes only 7 lines of FORTRAN code for encoding and decoding respectively.

关键词： Calendar date FORTRAN coding/decoding

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Analysis and performance of bidirectional decoding of convolutional codes over fading channels

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IEEE TRANSACTIONS ON COMMUNICATIONS 1998年第10期46卷 1292-1300页

作者： Belzile, J Gagnon, F Haccoun, D Ecole Technol Super Dept Elect Engn Montreal PQ H2T 2C8 Canada Ecole Polytech Dept Elect & Comp Engn Montreal PQ H3C 3A7 Canada

In this paper, the performance of suboptimal convolutional decoding over fading channels is explored. The suboptimal decoding algorithm used is the bidirectional algorithm. By estimating a "decoder weight spectrum" for the decoder, an "equivalent free distance" may be observed. Furthermore, by using this "decoder weight spectrum," useful estimations of the error probabilities are obtained and compared to computer-simulation results in the case of very slow and very fast fading. The resultant curves are shown to be very tightly related. Computer-simulation results are also shown for various signal-to-noise ratios, normalized Doppler spreads, and frame length on three typical fading channels: the Rayleigh fading channel with exponential and Bessel autocorrelation functions and the Rician fading channel with exponential autocorrelation function, We show that considerable gains (up to 4 dB) can be obtained with respect to a similar-complexity Viterbi decoder at a frame error probability P-e = 10(-3) and a slightly smaller gain (up to 1.8 dB) at a bit error probability P-b = 10(-5).

关键词： coding/decoding convolutional coding error analysis fading channel

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A new low-resolution and robust digital watermarking technique for the personalization of travel documents

A new low-resolution and robust digital watermarking techniq...

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5th Conference on Optical Security and Counterfeit Deterrence Techniques

作者： Herrigel, A Voloshynovskiy, S Rytsar, Y Up Great AG CH-8320 Fehraltorf Switzerland

ISBN: (纸本)0819452130

This paper presents a new approach for the protection of travel documents. We propose a digital watermarking technique which requires for the verification process a low scanning resolution of at least 72 DPI. The approach is based on the wavelet decomposition and supports three key aspects: Message encoding is accomplished by iterative error correction codes satisfying a nearly optimal channel capacity. This encoding is based on specific modulation that requires for the implementation a significant lower complexity as the often applied M-array modulation. The watermark embedding is applied in the wavelet domain based on stochastic driven perceptional criteria for a good quality and invisibility. The watermarking process is considered as a communication process with side information. The approach utilizes two different watermarks, one for the channel state information estimation and one for the informative watermark which carries as a payload the hidden information.

关键词： digital watermarking coding/decoding document protection

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A new very fast pull-in PLL system with anti-pseudo-lock function

A new very fast pull-in PLL system with anti-pseudo-lock fun...

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Symposium on VLSI Circuits

作者： Shirahama Taniguchi Nakashi Kyushu University Fukuoka Japan

PLLs (phase locked loops) are expected to be desirable components for clock extraction in high speed digital communication systems, typically in optical systems, because of the low cost, compactness, suitability to integration, and ease of treatment. The PLL for clock extraction requires a fast pull-in and small output jitter characteristics. In this paper, we describe a total PLL system, in which a further improvement of the pull-in time is realized and a pseudo lock (i.e. harmonic lock), which has been a serious problem in the past, can be avoided automatically. We have constructed the PLL system using a monolithic PU-IC for the PLL core part and 1.2 micron design rule PLAs for most of the remaining part of the system, and measured total performances of the system.

关键词： Phase-locked loops Emitter-coupled logic Very-large-scale integration Clocks coding/decoding Digital communication

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A versatile, efficient digital filter for decimation and interpolation

A versatile, efficient digital filter for decimation and int...

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Symposium on VLSI Circuits

作者： Brandt Wooley Texas Instrumenits Inc. Dallas TX USA University of Stanford Stanford CA USA

The area and power consumption of oversampled data converters are governed largely by the associated digital decimation and interpolation filters. This paper presents an area- and power-efficient programmable digital filter for decimation and interpolation in digital-audio applications. Several architectural and implementation features reduce the complexity of the filter and allow its implementation in a die area of only 3670 mils/sup 2/ (2.37 mm/sup 2/). The filter is first described in the context of decimation for an oversampled A/D converter employing a second-order sigma-delta modulator. Extensions of the filter to accommodate other modulators, as well as to perform interpolation for oversampled D/A conversion, are then discussed.

关键词： FIR digital filters Sigma-delta modulation Converters coding/decoding Very-large-scale integration CMOS integrated circuits, memory Random-access memories

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A high-speed and compact-size JPEG Huffman decoder using CAM

A high-speed and compact-size JPEG Huffman decoder using CAM

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Symposium on VLSI Circuits

作者： Komoto Homma Nakamura Oki Electric Industry Company Limited Tokyo Japan

A JPEG compliant Huffman decoder circuit has been developed. The circuit executes at 27 MHz in order to maintain image data transfer at CCIR 601 video rates. The circuit detects and decodes variable length Huffman codes in a single clock cycle by searching among all Huffman codes in the current table. The circuit utilizes a CAM with mask bits to perform this rapid search. The architecture also utilizes a double barrel shifter to window the next portion of the input bit stream to be examined, which makes the critical path as short as possible. According to the simulation results, the delay of execution in a cycle is 18.1 ns. The total memory size is 15K bits.

关键词： Huffman coding coding/decoding Image coding Associative memories CMOS integrated circuits Digital signal processing chips Data compression Very-large-scale integration High-speed integrated circuits

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Real-time decoding and display of structured video

Real-time decoding and display of structured video

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IEEE International Conference on Multimedia Computing and Systems (ICMCS)

作者： Bove Granger Watlington Media Laboratory Massachusetts Institute of Technology Cambridge MA USA

Structured (or model-based or analysis-synthesis) video refers to the representation of moving scenes in terms of component parts which are assembled according to scripting information to produce images for viewing. This sort of representation has advantages for both compression and interactivity. We describe a software implementation on a data-flow computer system which renders and composites two- and three-dimensional moving objects for display of compressed real and synthetic scenes.< >

关键词： coding/decoding Image databases

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