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APPLICATION OF pulse-code modulation TO SOUND-SIGNAL DISTRIBUTION IN A BROADCASTING NETWORK

PROCEEDINGS OF THE INSTITUTION OF ELECTRICAL ENGINEERS-LONDON 1972年第10期119卷 1442-&页

作者： SHORTER, DEL CHEW, JR Research Department British Broadcasting Corporation Tadworth UK

The application of digital methods to the internal distribution of high-quality sound signals in a broadcasting system allows a high and predictable standard of technical quality to be maintained with the minimum of attention by operating staff. pulse-code-modulation systems for the incorporation of a sound signal into a video waveform and for the multiplex distribution of programmes for the radio service will soon be in operation within the BBC, and the eventual use of national and international digital links for this purpose is envisaged. The feasibility of digital recording has also been demonstrated. This paper is mainly concerned with the special requirements to be met in the digital coding and decoding of broadcast-quality sound signals. Considerations of quantising noise, distortion and digit-error detection lead to a bit rate approaching half a megabit per second per channel, though this rate may be somewhat reduced as a result of current developments in digital companding. No attempt is made to deal with aspects of point-to-point transmission which are common to other digital systems, but the effects of digit-error rate and of timing jitter are considered, and tolerances are suggested.

关键词： digital communication systems digit error rate Radio and television broadcasting sound signal distribution timing jitter broadcasting network tolerances pulse-code modulation broadcast quality sound signals digital coding pulse code modulation codes broadcasting error detection codes decoding

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HISTORY OF pulse code modulation

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PROCEEDINGS OF THE INSTITUTION OF ELECTRICAL ENGINEERS-LONDON 1979年第9期126卷 889-892页

作者： CATTERMOLE, KW Department of Electrical Engineering Science University of Essex Colchester UK

The paper describes the factors leading to the invention of p.c.m., and the form first devised by A.H. Reeves. It outlines the development of early p.c.m. telephone systems up to about 1960, with emphasis on developments of which the author has personal experience. It surveys the life and work of the inventor, including his later ideas on encoding. Finally, it brings to light a little-known precursor of p.c.m., a form of picture telegraph invented by P.M. Rainey in 1921.

关键词： telephone systems invention reviews Telephony pulse-code modulation pulse code modulation history development

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DIFFERENTIAL CODING OF PAL VIDEO SIGNALS USING INTRAFIELD PREDICTION

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PROCEEDINGS OF THE INSTITUTION OF ELECTRICAL ENGINEERS-LONDON 1977年第12期124卷 1139-1147页

作者： DEVEREUX, VG Research Department British Broadcasting Corporation Tadworth UK

The paper discusses the application of differential pulse-code modulation (d.p.c.m.) and hybrid d.p.c.m./p.c.m. coding as a means of reducing the bit rate required for broadcast-quality System I (Pal, 625-line, 5.5 MHz) video signals. In the d.p.c.m. codes investigated, each codeword indicated the difference in magnitude between a sample of a video signal and a prediction of this sample based on samples already transmitted in the same and/or previous line periods with a sampling frequency equal to three times the colour subcarrier frequency. The codes examined required the transmission of between 3 and 6 bits per sample. Subjective test results are given for the picture impairment caused by quantising errors and transmission errors. The tests on quantising errors indicated that d.p.c.m. could provide a saving of nearly 2 bits per sample compared with p.c.m. A comparison of subjective test results and measurements of the r.m.s. quantising errors for d.p.c.m. and p.c.m. indicates that the picture impairment corresponding to a given signal/noise ratio is similar for both d.p.c.m. and p.c.m.

关键词： Signal processing and detection quantising errors picture impairment transmission errors colour television video signals PAL video signals differential coding pulse-code modulation PCM Radio and television transmitters intrafield prediction codes encoding

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PPM VERSUS PCM FOR OPTICAL LOCAL-AREA NETWORKS

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IEE PROCEEDINGS-I COMMUNICATIONS SPEECH AND VISION 1992年第3期139卷 241-250页

作者： MARTIN, JD HAUSIEN, HH School of Electronic and Electrical Engineering University of Bath Bath UK

pulse-position modulation (PPM) is presented within the context of a local-area network (LAN) application. A simplified analysis is used to calculate the advantage of converting from pulse-code modulation (PCM) to PPM signalling in a LAN, assuming in each case the same fibre network and the same optical transmitting device. Although PPM exploits its wide bandwidth to give greater sensitivity in noise, the true system advantage is obtainable only by using a large peak-to-mean-power ratio in the transmitter. It is shown that this performance is possible for both a laser diode and for an edge-emitting LED. An experimental system is reported, operating at a data rate of 4 Mbit/s, and good correspondence with theory is obtained. Design procedures are given for broad classes of situation.

关键词： OPTICAL FIBERS LOCAL AREA NETWORKS pulse-POSITION modulation pulse-code modulation SIGNAL PROCESSING

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Generalized PCM Coding of Images

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2012年第8期21卷 3801-3806页

作者： Prades Nebot, Jose Morbee, Marleen Delp, Edward J. Univ Politecn Valencia Inst Telecommun & Multimedia Applicat Valencia 46022 Spain Univ Ghent Dept Telecommun & Informat Proc B-9000 Ghent Belgium Purdue Univ Sch Elect & Comp Engn W Lafayette IN 47907 USA

pulse-code modulation (PCM) with embedded quantization allows the rate of the PCM bitstream to be reduced by simply removing a fixed number of least significant bits from each codeword. Although this source coding technique is extremely simple, it has poor coding efficiency. In this paper, we present a generalized PCM (GPCM) algorithm for images that simply removes bits from each codeword. In contrast to PCM, however, the number and the specific bits that a GPCM encoder removes in each codeword depends on its position in the bitstream and the statistics of the image. Since GPCM allows the encoding to be performed with different degrees of computational complexity, it can adapt to the computational resources that are available in each application. Experimental results show that GPCM outperforms PCM with a gain that depends on the rate, the computational complexity of the encoding, and the degree of inter-pixel correlation of the image.

关键词： Binning interpolative coding pulse-code modulation quantization

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NONLINEAR PREDICTION IN IMAGE-CODING WITH DPCM

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ELECTRONICS LETTERS 1990年第17期26卷 1357-1359页

作者： LI, J MANIKOPOULOS, CN Dept. of Electr. & Comput. Eng. New Jersey Inst. of Technol. Newark NJ USA

In contrast to the traditional linear differential pulse code modulation (DPCM) design for the encoding of images, a new, nonlinear, neural network-based, DPCM technique has been devised. The predictor is designed by supervised training, based on a typical sequence of pixel values in an image. A function link neural network architecture has been used to design the predictor for one dimensional (1-D) DPCM. Computer simulation experiments in still image coding have shown that the resulting encoders work very well. At a transmission rate of 1 bit/pixel, for the image LENA, the 1-D neural network DPCM provides a 4.2 dB improvement in SNR over the standard linear DPCM system.

关键词： DPCM LENA SNR encoding encoding filtering and prediction theory function link neural network architecture image coding neural nets neural network-based nonlinear prediction picture processing pixel values pulse-code modulation still image supervised training

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CROSS-CORRELATION METHOD FOR ANALYZING PHASE AND GAIN ERRORS IN PCM SYSTEMS FOR COLOR-TELEVISION

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PROCEEDINGS OF THE INSTITUTION OF ELECTRICAL ENGINEERS-LONDON 1975年第4期122卷 367-368页

作者： WADE, JG PLYMOUTH POLYTECH PLYMOUTH PL48AADEVONSHIREENGLAND

Quantizing error in a PCM system for color television can lead to subcarrier phase and gain errors in a decoded color signal. These errors depend upon the signal/noise ratio at the encoder input, and crosscorrelation ... 详细信息

关键词： crosscorrelation method gain errors correlation methods video signals Television and video equipment, systems and applications pulse-code modulation digital computer model codes decoding Signal processing and detection colour television encoder decoder system error analysis signal/noise ratio phase errors encoder input pulse code modulation decoded colour signal Information theory PCM systems encoding

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modulation SCHEME SUITABLE FOR INFRARED BIOTELEMETRY

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ELECTRONICS LETTERS 1985年第14期21卷 601-602页

作者： WELLER, C Division of Bioengineering Clinical Research Centre Harrow UK

Telemetering physiological signals from hospital patients by time-sharing infra-red radiation of fixed wavelength means that the limited time available for encoding each data channel imposes constraints on modulation ... 详细信息

关键词： limited time available for encoding Optical communication Telemetering systems telemetering systems hospital patients codes Patient diagnostic methods and instrumentation telemetering physiological signals infra-red biotelemetry Telemetry biomedical electronics unconventional pulse code IR links pulse-code modulation light emitting diodes Biomedical measurement and imaging patient monitoring constraints on modulation methods time-sharing infra-red radiation of fixed wavelength optical links modulation scheme digital modulation methods analogue modulation

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ROBUST FRAMING RECEIVER FOR 2.048 MBIT/S PCM SYSTEMS

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ELECTRONICS LETTERS 1990年第14期26卷 1077-1079页

作者： DODDS, DE PAN, SM Dept. of Electr. Eng. Saskatchewan Univ. Saskatoon Sask. Canada

A faster, more robust framing detector for the multiplexing format of 2.048 Mb/s PCM systems is proposed. Existing framing detectors look for a seven bit syncword. By simply storing 512 bits and searching for the combination of two seven bit syncwords, the search time is improved by a factor of four and operation is permissible with a greatly increased channel error rate.

关键词： 2.048 Mbit/s 512 bit PCM systems channel error rate tolerance combination of two seven bit syncwords digital communication systems frame synchronisation multiplexing format pulse-code modulation receivers robust framing detector robust framing receiver search time storing 512 bits synchronisation telephone systems two syncword system

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pulse-coded information transmission across an axially excited chiral-sculptured thin film in the Bragg regime

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2001年第1期28卷 59-62页

作者： Geddes, JB Lekhtakia, A Penn State Univ Dept Engn Sci & Mech CATMAS University Pk PA 16802 USA

Although a monochromatic plane wave of a certain circular polarization state and wavelength may be almost completely reflected by a chiral sculptured thin film, we show here that information coded in rectangular pulses can still he transmitted across the film-provided the rise and fall rimes of the pulses are sufficiently small and the pulse widths are sufficiently large. (C) 2001 John Wiley & Sons, Inc.

关键词： chiral-sculptured thin films circular Bragg phenomenon pulse-code modulation

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