
	Where results make sense

Topic: Channel coding

Related Topics

Line code

Hamming code

Golay code

Huffman coding

Binary coding

Adaptive modulation

PCM

Coded orthogonal frequency division multiplexing

Bandwidth

Channel capacity

Sampling (signal processing)

Telecommunication

B8ZS

Encoding

Digital signal

In the News (Thu 12 Nov 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Research: Channel Coding for Mobile Communications, ANT, Universität Bremen
		Channel coding is power efficient: Compared to the uncoded case, the same error rates are achieved with much less transmit power at the expense of a bandwidth expansion.
		Lecture 'Channel Coding' (ANT, University of Bremen)
		Iterative decoding for SCCS and optimum ML-decoding for CCRPC and CSP
	www.comm.uni-bremen.de /research/coding (363 words)

	Noisy channel coding theorem - Wikipedia, the free encyclopedia
		In information theory, the noisy-channel coding theorem establishes that however contaminated with noise interference a communication channel may be, it is possible to communicate digital data (information) error-free up to a given maximum rate through the channel.
		4 Channel coding theorem for non-stationary memoryless channels
		With Turbo codes and the computing power in today's digital signal processors, it is now possible to reach within 1/10 of one decibel of the Shannon limit.
	en.wikipedia.org /wiki/Channel_coding (1245 words)

	Channel capacity - Wikipedia, the free encyclopedia
		By the noisy-channel coding theorem, the channel capacity of a given channel is the limiting information transport rate (in units of information per unit time) that can be achieved with vanishingly small error probability.
		The key result states that the capacity of the channel, as defined above, is given by the maximum of the mutual information between the input and output of the channel, where the maximization is with respect to the input distribution.
		The channel coding theorem states that for any ε > 0 and for any rate less than the channel capacity, there is an encoding and decoding scheme that can be used to ensure that the probability of block error is less than ε > 0 for sufficiently long message block M.
	en.wikipedia.org /wiki/Channel_capacity (377 words)

	Department TAIT - Lecture Channel Coding
		Channel coding is a data processing technique that is used in digital communication and data storage systems.
		Channel coding is done in two steps: The channel encoder generates redundant symbols that are transmitted or stored together with the other data.
		Code design (how to add the redundand symbols) and decoding thechniques (how to use these redundant symbols for error correction) are the two main areas in channel coding.
	tait.e-technik.uni-ulm.de /~schmidt/ccod.html (326 words)

	High-definition television - Wikipedia, the free encyclopedia
		The native bitrate of HDTV formats cannot be supported by 6-8MHz standard-definition television channels for over-the-air broadcast and consumer distribution media, hence the widespread use of compression in consumer applications.
		SMPTE 292M interconnects are generally unavailable in consumer equipment, partially due to the expense involved in supporting this format, and partially because consumer electronics manufacturers are required (typically by licensing agreements) to provide encrypted digital outputs on consumer video equipment, for fear that this would aggravate the issue of video piracy.
		In February 2006, Televisa's XHUAA in Tijuana began its HDTV transmissions on channel 20.
	en.wikipedia.org /wiki/HDTV (4210 words)

	Channel coding; Hamming distance (Site not responding. Last check: 2007-11-02)
		The task of channel coding is to represent the source information in a manner that minimises the error probability in decoding.
		It is apparent that channel coding requires the use of redundancy.
		The rate R of a channel code is the average ratio of the source sequence length to the channel code length.
	www.cs.ucl.ac.uk /staff/S.Bhatti/D51-notes/node30.html (370 words)

	Noisy Channel Coding Theorem
		If the efficiency is less than the capacity of the digital channel, an error-correcting code exists that has the property that as the length of the code increases, the probability of an error occurring in the decoded block approaches zero.
		The key for this capability to exist is that the code's efficiency be less than the channel's capacity.
		Figure 1: The capacity per transmission through a binary symmetric channel is plotted as a function of the digital channel's error probability (upper) and as a function of the signal-to-noise ratio for a BPSK signal set (lower).
	cnx.org /content/m0073/latest (408 words)

	Tutorial (CDMA Reference Blockset) (Site not responding. Last check: 2007-11-02)
		In addition to the PN codes, there is a set of length-64 mutually orthogonal codes called the Walsh code, which is used for ensuring orthogonality between the signals for different users receiving from the same base station.
		The channel coding operations in the forward CDMA operations use 20 ms frames for all channels, except for the Sync channel, which is coded using 26.666 ms frames.
		These Walsh codes are orthogonal to each other, and the different symbol streams are spread by their respective Walsh code (in bipolar form) and added together in a manner such that the weight given to each corresponds to the intended power in that channel.
	web.ece.umr.edu /computing/unix/software/matlab/toolbox/cdma/cdmatutorial5.html (1662 words)

	Arithmetic Channel Coding (Site not responding. Last check: 2007-11-02)
		Arithmetic coding is a source coding algorithm which encodes the output of any discrete stationary source into a sequence of independent and uniformly distributed random variables.
		The code is specified by the probabilities and cumulative probabilities of the source.
		The decoder used in arithmetic source coding is based on the noiseless assumption and it cannot be used to decode the output of a noisy channel.
	lcavwww.epfl.ch /~weidmann/acc.html (246 words)

	INTRODUCTION TO AHA CODING CLINIC REFERENCE NOTATIONS
		The Coding Clinic provides specific information and guidelines that are helpful for determining proper coding, and is used by CMS in reviewing claims.
		Channel Publishing has developed the AHA Coding Clinic reference notations to help coders access the official coding advice found throughout all issues of the Coding Clinic.
		This information has been referenced in two ways: 1) direct code by code reference notations, 2) a categorical index of articles that are too broad in scope to be assigned to a particular code.
	www.channelpublishing.com /ahacodingclinicintro.htm (429 words)

	Speech Coding
		Speech coding techniques can be broadly divided into two classes: waveform coding that aims at reproducing the speech waveform as faithfully as possible and vocoders that preserve only the spectral properties of speech in the encoded signal.
		Using new techniques for channel coding and equalization, it is possible to transmit the 8 kbps speech in a robust fashion over the mobile radio channel, in spite of channel noise, signal fading and intersymbol interference.
		The complexity of a coding algorithm is the processing effort required to implement the algorithm, and it is typically measured in terms of arithmetic capability and memory requirement, or equivalently in terms of cost.
	cslu.cse.ogi.edu /HLTsurvey/ch10node4.html (1978 words)

	ADAPTIVE SOURCE-CHANNEL SUBBAND VIDEO CODING FOR WIRELESS CHANNELS (Site not responding. Last check: 2007-11-02)
		For each subband, the source coding rate as well as the level of protection (quantified by the channel coding rate) are jointly chosen to minimize the total mean-squared distortion suffered by the video coder.
		The aim of a joint source-channel coding approach is to optimally allocate bits between the source and channel coders to minimize total distortion, while satisfying a constraint on the total rate.
		These codes make it practical to achieve a wide range of channel coding rates using a single encoder and viterbi decoder by simply pucturing the coded bitstream according to the level of protection desired.
	www.cfar.umd.edu /~murari/mmsp97/mmsp97.html (1691 words)

	3rd GPP Multiplexing and channel coding (FDD)
		Channel coding scheme is a combination of error detection, error correcting, rate matching, interleaving and transport channels mapping onto/splitting from physical channels.
		Code block segmentation is performed after the concatenation of the transport blocks when the number of bits in a TTI is larger than Z. The maximum size of the code blocks depend on if convolutional or turbo coding is used for the TrCH.
		Code blocks are delivered to the channel coding block.
	www.fortunecity.com /business/tisch/1301/id58.htm (1171 words)

	Learn more about Modulation in the online encyclopedia. (Site not responding. Last check: 2007-11-02)
		When OFDM is used in conjunction with channel coding techniques, it is described as 'Coded orthogonal frequency division modulation' (COFDM).
		Where the signal is a simple low speed on-off indication, as in morse code or radioteletype (RTTY) transmission, modulation is often known as 'keying' as in the terms
		Where Morse code is used to turn the carrier wave on and off, the term used is not 'amplitude keying', but 'continuous wave' (CW) operation.
	www.onlineencyclopedia.org /m/mo/modulation.html (247 words)

	Turbo Codes
		Turbo Codes are a class of powerful error correction codes that were introduced in 1993 by a group of researchers from France, along with a practical decoding algorithm.
		Since their introduction, turbo codes have been proposed for low-power applications such as deep-space and satellite communications, as well as for interference limited applications such as third generation cellular and personal communication services.
		This project, called the Iterative Solutions Coded Modulation Library (ISCML) runs in matlab, yet is optimized for rapid run-time by implementing the most computationally intensive parts in C (which are called from matlab as c-mex functions).
	www.csee.wvu.edu /~mvalenti/turbo.html (305 words)

	Channel and source coding (Site not responding. Last check: 2007-11-02)
		As an illustration of channel coding, suppose that a space probe transmits an image from Mars back to Earth, but the transmission is partially corrupted due to atmospheric noise.
		Error-control coding is based on carefully adding redundancy so as to combat the noise; the decoding problem at the receiver (Earth) is to use the corrupted transmission and code structure to correctly infer the transmitted codeword (image).
		On the other hand, the goal of source coding is to remove statistical redundancy from a data source (e.g., images) so as to compress it optimally, either losslessly (exact reconstruction) or in a lossy manner.
	www.eecs.berkeley.edu /~wainwrig/Test/coding/node1.html (284 words)

	Channel Coding
		Channel coding is a viable method to reduce information rate through the channel and increase reliability.
		This goal is achieved by adding redundancy to the information symbol vector resulting in a longer coded vector of symbols that are distinguishable at the output of the channel.
		Another brief explanation of channel coding is offered in Channel Coding and the Repetition Code.
	cnx.rice.edu /content/m10174/latest (322 words)

	The Laws of Cryptography: Coding and Information Theory
		In this case the average code length is the same as the entropy.
		The channel capacity is represented as a fraction or percentage of the total rate at which bits can be sent physically over the channel.
		Notice the big difference between this code and the triple transmission code: this code has a transmission rate of 50%, while the triple code has a rate of only 33.3%, even though both do single-error correction.
	www.cs.utsa.edu /~wagner/laws/coding.html (2125 words)

	Modulation
		When OFDM is used in conjunction with channel coding techniques, it is described as Coded orthogonal frequency division multiplexing (COFDM).
		OFDM is strictly a channel access method and not a modulation scheme.
		The use of on-off keying to transmit Morse code at radio frequencies is known as continuous wave (CW) operation.
	www.brainyencyclopedia.com /encyclopedia/m/mo/modulation.html (782 words)

	A Tutorial on Convolutional Coding with Viterbi Decoding
		Suppose that we have a system where a '1' channel bit is transmitted as a voltage of -1V, and a '0' channel bit is transmitted as a voltage of +1V.
		In this simulation, a '1' channel bit is transmitted at a level of -1V, and a '0' channel bit is transmitted at a level of +1V.
		The code rate, k/n, is expressed as a ratio of the number of bits into the convolutional encoder (k) to the number of channel symbols output by the convolutional encoder (n) in a given encoder cycle.
	home.netcom.com /~chip.f/viterbi/tutorial.html (2090 words)

	Error Control Coding
		Since such coding detects or corrects errors incurred in the communication or storage channel, it is often referred to as channel coding.
		Channel coding for fixed channels is a relatively mature field, but coding for time varying channels is a relatively young and immature field.
		Channel coding for storage has also been very successful in boosting capacity, and remains a topic of active research.
	users.ece.gatech.edu /~vkm/nii/node41.html (252 words)

	Coding
		Without coding, the antenna for the transmitter would be too big or the signal-to-noise ratio required would be too high (which translates to short battery life).
		Coding is guaranteed to work by Shannon's famous Channel Coding Theorem.
		Shannon's Channel Coding Theorem tells us: as long as the data rate is smaller than a parameter associated with the channel (known as the channel capacity), it is possible to transmit data with virtually no error (with the help of a coding scheme).
	www.eie.polyu.edu.hk /~enmzwang/coding.html (148 words)

	CHANNEL CODING PAGE (Site not responding. Last check: 2007-11-02)
		LDPC codes first published by the author in 1962 are the ancestors of Turbo codes.
		Multilevel coded modulations (MLC) are also studied as an efficient coding scheme for non binary modulations.
		Factor graphs are used to represent the coded multiple access system and iterative APP decoding is described as a sum-product algorithm.
	www.comelec.enst.fr /~boutros/coding (1119 words)

	Michelle Effros (Caltech) : Applications / Joint Source and Channel Coding
		Current work in joint source and channel code design combines techniques for optimizing source codes to match channel noise characteristics with techniques for optimizing channel codes to match source code characteristics into a single joint design aimed at minimizing the end-to-end distortion experienced in the communication system as a whole.
		The most important factor in that joint design seems to be the bit allocation between the source coding bits (used to describe the original data string) and the channel coding bits (used to protect the source coding bits from channel errors).
		The resulting codes may be employed on a wide range of channels (e.g., AWGN channels and Rayleigh fading channels with and without receiver side information) with significant performance benefits.
	www.ee2.caltech.edu /Faculty/effros/jscc.html (360 words)

	Technology Channel - Coding
		Code reader The co. introduces its new 2D code reader, the PD60/65, which can read 2D codes from 360 deg on metal even if it is stained, chipped or tilted.
		Code clarity on various products and materials is said not to degrade, even at high line...
		Coding that's ripe for the picking Pacific Tomato Growers, a leading, family-operated grower/packer based in Palmetto, FL, adopts ink-jet coding in a big way, to ensure more precise, quality container codes.
	www.packagingdigest.com /newsite/InfoChannel/info_code.php (433 words)

	Contents (Site not responding. Last check: 2007-11-02)
		In fact, for coding theory and cryptography, many systems use such large parameters that working practical ``by hand'' is virtually impossible and computers are not just useful but required.
		Cyclic codes are a very broad class of codes which includes, for example Reed-Solomon codes, the codes used on todays CDs.
		Other codes, such as the Goppa codes and the low density parity check codes, do not need group theory but were too advanced to fit naturally into chapter 3.
	web.usna.navy.mil /~wdj/book/node1.html (878 words)

	GSM Channel Coding
		This is split into B full rate or 16 half rate traffic channels, plus the signaling channels.
		The coding is complex in order to have the maximum chance to detect and correct the errors encountered in a typical propagation path.
		The output of the speech coder is encrypted, coded and interleaved in a sophisticated way to allow Forward Error Correction to be applied.
	www.cellular.co.za /gsm-channelcoding.htm (215 words)

	Channel Coding (Site not responding. Last check: 2007-11-02)
		GPRS employs different channel coding to achieve different error correcting capabilities and achieving different data rates.
		Under very bad channel conditions, we may use CS-1 and get a data rate of 9.05kbit/s per GSM slot with very reliable coding.
		Under very good channel conditions we transmit without convolutional coding and achieve a data rate of 21.4kbit/s.
	www.it.iitb.ac.in /~satyajit/seminar/node20.html (133 words)

	Stereo compatible multi-channel audio coding patent invention
		[0003] The present invention relates to multi-channel audio coding and in particular to a concept of generating and using a parametric representation of a multi-channel audio signal that is fully backwards compatible to parametric stereo playback environments.
		Recent approaches for the parametric coding of multi-channel audio signals (parametric stereo (PS), Binaural Cue Coding (BCC) etc.) represent a multi-channel audio signal by means of a down-mix signal (could be monophonic or comprise several channels) and parametric side information, also referred to as "spatial cues", characterizing its perceived spatial sound stage.
		Normally, the carrier channel (channels) will include subband samples, spectral coefficients, time domain samples, etc., which provide a comparatively fine representation of the underlying signal, while the parametric data do not include such samples of spectral coefficients but include control parameters for controlling a certain reconstruction algorithm instead.
	www.freshpatents.com /Stereo-compatible-multi-channel-audio-coding-dt20060622ptan20060133618.php (1520 words)

Try your search on: Qwika (all wikis)