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| | Forward error correction - Wikipedia, the free encyclopedia |
 | | The most recent (early 1990s) development in error correction is turbo coding, a scheme that combines two or more relatively simple convolutional codes and an interleaver to produce a block code that can perform to within a fraction of a decibel of the Shannon limit. | | | The maximum fraction of errors that can corrected is determined in advance by the design of the code, so different forward error correcting codes are suitable for different conditions. | | | FEC is accomplished by adding redundancy to the transmitted information using a predetermined algorithm. |
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http://en.wikipedia.org/wiki/Forward_error_correction
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| | Error correction and detection - Wikipedia, the free encyclopedia |
| | Given the goal of error correction, the idea of error detection may seem to be insufficient. | | | Shannon's theorem sets an upper bound to the error correction rate that can be achieved (and thus the level of noise that can be tolerated) using a fixed amount of redundancy, but does not tell us how to construct such an optimal encoder. | | | Information theory tells us that whatever the probability of error in transmission or storage, it is possible to construct error-correcting codes in which the likelihood of failure is arbitrarily low, although this requires adding increasing amounts of redundant data to the original, which might not be practical when the error probability is very high. |
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http://en.wikipedia.org/wiki/Error-correction
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| | FEC |
| | A number of FEC algorithms are being used including Hamming code, Reed-Solomon code and Bose-Chandhuri-Hocquenghem code. | | | Forward Error Correction (FEC) is a technique that has been used for a number of years in submarine fiber optic systems. | | | The input BER is a measure of errors that occur in the transmission channel. |
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http://www.mrfiber.com/FEC.htm
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| | RFC 2733 - An RTP Payload Format for Generic Forward Error Correction |
| | 6.2 FEC Header This header is 12 bytes. | | | FEC Header: The FEC header is the header information contained in an FEC packet. | | | RFC 2733 Generic FEC December 1999 4 Parity Codes For brevity, we define the function f(x,y,..) to be the XOR (parity) operator applied to the packets x,y,... |
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http://www.muonics.com/rfc/rfc2733.php
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| | Forward Error Correction |
| | Hence, in an FEC system, the receiver detects and corrects errors in real time as the data is being received. | | | FEC overcomes these hurdles by allowing the receiver to detect and correct errors without having the transmitter boost its power levels or retransmit corrupted data packets. | | | FEC is an important advantage with digital communication technologies; FEC does not work with analog communications because the degradation of analog signals cannot be effectively corrected. |
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http://www.techonline.com/community/ed_resource/feature_article/20016?print
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| | Airlinx - Forward Error Correction |
| | Error correction techniques, on the other hand, add enough data encoding to allow the detection and correction of errors on the fly, and do not add significant latency, degrading traffic throughput. | | | In error detection an isolated error is detected in a block of data, and the data is discarded and a request for re-transmission is made to the source. | | | FEC is an error control technique developed by the aerospace industry for deep space exploration that can locate and correct transmission errors. |
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http://www.airlinx.com/details/ForwardErrorCorrection.html
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| | 28692.000518&ELEMENT_SET=DECL |
| | This is sometimes known as ARQ with incremental forward error correction. | | | Known in the art in the use of forward-error-correction that includes convolutional encoding in the transmission of encoded digital data over a noisy channel from a transmitter to a receiver is a branch metric computer for a Viterbi-algorithm based convolutional decoder. | | | Various forms of forward error correction are known including convolutional and block coding. |
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http://www.wipo.int/cgi-pct/guest/getbykey5?KEY=00/28692.000518&ELEMENT_SET=DECL
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| | Forward Error-Correction Coding |
| | Forward error-correction coding (also called channel coding) is a type of digital signal processing that improves data reliability by introducing a known structure into a data sequence prior to transmission or storage. | | | Forward error-correction coding represents the most efficient, economical, and predictable way of improving the reliability of transmitted or stored data. | | | This structure enables a receiving system to detect and possibly correct errors caused by corruption from the channel and the receiver. |
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http://www.aero.org/publications/crosslink/winter2002/04.html
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| | Overview of Forward Error Correction |
| | Therefore the goal is to choose parity bits to correct as many errors at possible (getting as close as possible to the (d-1)/2 error correction limit (see section 1.1), while keeping the communications efficiency as high as possible. | | | Although error detection is a subset of forward error correction it will not be covered in detail. | | | Forward error correction is such a large topic that it can only be done justice with a full semester course and not a homework assignment such as this one. |
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http://ece.wpi.edu/courses/ee535/hwk97/hwk4cd97/bad/paper.html
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| | Forward Error Correction in Firmware Systems |
| | Forward Error Correction (FEC) is an art where errors in a transmitted data payload may be corrected by a receiver without referring to the transmitter for re-transmission or correction. | | | The key value of Forward Error Correction (FEC) technology is that it allows the receiver of a corrupted message the potential to correct the message without referring to the transmitter of the message. | | | FEC codes are an example of Error Correcting Codes ("ECC"), wherein it is possible for Transmitted Data ("TX") stream, corrupted by the influence of Additive White Gausian Noise ("AWGN"), to be reconstructed by the receiver such that the transmit stream equals the receive stream ("RX"). |
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http://www.virtualperipherals.com/Library/Firmware-Forward-Error-Correction.asp
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| | Patent 5127013: Data communication system |
| | When an error exists in data received in the error correction mode, a message is recorded subsequent to the recording of the received data to announce the presence of the error, thus facilitating recognition of the occurrence of error. | | | In such a case, an error is undesirably caused in the recorded image although the error correction mode has been selected. | | | A data communication system, capable of operating in an error correction mode, is capable of producing, when data received in an error correction mode could not be correctly recorded, information indicative of the occurrence of such a recording failure. |
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http://www.freepatentsonline.com/5127013.html
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| | rfc3452.txt |
| | FEC Payload ID and FEC Object Transmission Information A document that specifies an FEC scheme and reserves a value of FEC Encoding ID MUST define the fields and their packet formats for the FEC Payload ID and specify the information in the FEC Object Transmission Information according to the needs of the encoding scheme. | | | The FEC Payload ID MUST be included in the data packet header fields, as it provides a description of the encoding symbols contained in the packet. | | | This document specifies the FEC information that must be carried in data packets and the other FEC information that must be communicated either out-of-band or in data packets. |
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http://www.ietf.org/rfc/rfc3452.txt
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| | Using bit-error-rate testers to test-drive FEC codes - 9/4/2003 - EDN |
| | Approaches that correct for bit errors during digital communication vary from simple error-detection mechanisms, to non-real-time correction capability, to real-time, on-the-fly error correction. | | | This type of analysis computes the corrected error rate by counting errors only when the error rate exceeds eight byte errors per 204-byte packet (Table 1). | | | Whenever the number of symbol errors within the 204-byte block is less than or equal to eight, you can remove the errors from further error counting and analysis, because an error corrector would have removed them. |
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http://www.edn.com/article/CA318711.html
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| | PLC-1 Forward Error Correction |
| | Nowadays FEC is everywhere around us; it is extensively used in many (if not most) digital communication systems, in Compact Disk technology, (to tolerate scratched CDs), in satellite communications, etc
Unfortunately, only a few PLC technologies offer an efficient Forward Error Correction algorithm, combined with an error detection scheme. | | | FEC coding typically enhances decoded Bit Error Rate values three order of magnitude" relative to systems not implementing any Forward Error Correction techniques. | | | For example, the CEBus PLC standard includes an excellent CRC-based error detection algorithm for PL medium, but has no forward error correction.. |
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http://www.clic.net/~metricom/fec.html
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| | Forward Error Correction for Binary Code |
| | The example that I will give is a simplistic version of binary forward error correction. | | | This type of error correction is useful when dealing with long transfer times where echo checking and other corretion strategies would either not work or the time it takes for them to do their job is prohibitive. | | | This is an Example of Forward Error Correcting Binary Code |
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http://www.ecst.csuchico.edu/~dalleman/error_correction.htm
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| | Brainstorms: Error Correction Runs Deep |
| | For example, the "need" of error correction, the multitude of ways that "errors" are avoided, the limited applicability of the parity code concept to mutifunctional RNAs (along with the myriad ways by which the parity is broken) all point to a pretty different mode of design, an entirely different "personality". | | | The fact that many layers of error correction are biological universals raises the possibility that life, without error correction, either cannot exist or cannot exist very long. | | | In addition to looking at the source or cause of error correction, it is also interesting to look at the result or effect of error correction on the processes of evolutionary change. |
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http://www.iscid.org/boards/ubb-get_topic-f-6-t-000170.html
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| | Software FEC in computer communications |
| | Abstract: Forward Error Correction (FEC) is seldom used in computer networks, because of perplexity in doing the necessary encoding/decoding in software. | | | In such cases, Forward Error Correction (FEC) techniques can be used, consisting in the transmission of redundant packets (based on error correcting codes) to allow the receivers to recover from independent packet losses. | | | Despite the widespread use of error correcting codes in many fields of information processing, and a general consensus on the usefulness of FEC techniques within some of the Internet protocols, very few actual implementations exist of the latter. |
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http://info.iet.unipi.it/~luigi/fec.html
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| | Reed-Solomon error correction - Wikipedia, the free encyclopedia |
| | Reed-Solomon error correction is a coding scheme which works by first constructing a polynomial from the data symbols to be transmitted and then sending an over-sampled plot of the polynomial instead of the original symbols themselves. | | | A Reed-Solomon code is twice as powerful at erasure correction than at error correction, and any combination of errors and erasures can be corrected as long as the equation 2E + S ≤ (n−k) is satisfied, where E is the number of errors and S is the number of erasures in the block. | | | This code can correct up to 2 byte errors per 32-byte block. |
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http://en.wikipedia.org/wiki/Reed-Solomon_code
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| | ipedia.com: Reed-Solomon error correction Article |
| | Reed-Solomon error correction is a coding scheme which works by first constructing a polynomial from the data symbols to be transmitted and then sending an over-sampled plot of the polynomial instead of the original symbols themselves. | | | Reed-Solomon error correction is a coding scheme which works by first constructing a polynomial from the data symbols to be transmitted and then sending an over-sampled plot of the polynomial instead... | | | A Reed-Solomon code is twice as powerful at erasure correction than at error correction, and any combination of errors and erasures can be corrected as long as the equation 2E + S ≤ (n−k) is satisfied, where E is the number of errors and S is the number of erasures in the block. |
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http://www.ipedia.com/reed_solomon_error_correction.html
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| | CD-Recordable FAQ - section 2 |
| | A frame holds 24 bytes of user data, 1 byte of subcode data, and 8 bytes of parity (error correction), for a total of 33 bytes. | | | The error correction that keeps your CDs sounding the way they're supposed to, even when scratched or dirty, is applied at a lower level. | | | The bits are processed by two error correction stages, referred to as C1 and C2. |
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http://www.cdrfaq.org/faq02.html
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| | World Intellectual Property Organization |
| | The error magnitude 141 is provided to an error corrector, such as the error corrector 150 of FIG. | | | The decoder (500) of claim 7, wherein each error magnitude of the plurality of error magnitudes (331, 341, 351, 361) is based on a sum of a-product term from a corresponding coefficient multiplier (325a-d) in each slice element (320) of the plurality of slice elements (320, 320') in the second evaluator (300). | | | For each error that the error locator 130 locates, an error corrector 150 determines the corrected codeword c (x) 151, based on the location 131 and magnitude 141 of this error. |
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http://www.wipo.int/ipdl/IPDL-CIMAGES/view/pct/getbykey5?KEY=01/39378.010531&ELEMENT_SET=DECL
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| | Department of Energy Information Bridge - full-text scientific and technical reports (gray literature) |
| | Realization of the importance of nearby n= 1 mode components m= 1 and m= 3 has led to a revision of the error field correction algorithm. | | | Error field optimization on DIII-D tokamak plasma discharges has routinely been done for the last ten years with the use of the external ''n= 1 coil'' or the ''C-coil''. | | | Improved plasma performance is achieved by optimizing B{sub pen} by varying the applied correction coil currents. |
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http://www.osti.gov/bridge/product.biblio.jsp?osti_id=813641
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| | Forward Error Correction for Video Transmission over CDMA |
| | The final step was to design an intelligent error correction scheme based on the innovations. | | | The important bits in a video stream were identified by means of a "forced error" simulation. | | | Using that, this thesis proved that an intelligent FEC scheme is needed to protect all important bits. |
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http://www.cc.gatech.edu/grads/s/Srinivasan.Seetharaman/video
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| | ECC Technologies, Inc. ECC FAQs |
| | Error correction is the process of detecting bit errors and correcting them and can be done in software or hardware. | | | Error correction is currently being used to make high capacity storage devices such as magnetic and optical disk and tape reliable. | | | Error correction can either be done in hardware or software depending upon how fast it has to be done. |
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http://members.aol.com/mnecctek/faqs.html
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| | Technology Transfer - Forward Error Correction (FEC) Technology |
| | Interleaving is a key component of many digital communication systems involving forward error correction coding. | | | In this case, the interleaving parameters have been carefully selected to match the error correcting capabilities of the codes involved. | | | A comprehensive archive of papers on FEC technology has been published. |
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http://www.crc.ca/en/html/crc/home/tech_transfer/fec
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| | AMCC Adds Forward Error Correction to Its DWDM Multi-Rate Solutions |
| | S3067 -- Transceiver The S3067 is the industry's first integrated mux/demux solution that supports forward error correction rates. | | | Detected error and accumulated error counts can be accessed by the user, either through a processor interface, a FPGA interface or in a number of cases via I/O signal pins. | | | An external oscillator is required to minimize the PLL lock time and provide a stable output clock source in the absence of serial input data. |
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http://www.prnewswire.com/cgi-bin/stories.pl?ACCT=104&STORY=/www/story/12-10-1999/0001093356&EDATE=
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| | TRL News |
| | For example, when the new algorithm was used in a random 4-byte error correction circuit designed and fabricated by using standard 0.35-um ASIC technology, the algorithm provided parallel processing of a 320-bit-long sequence of data in 45 nanoseconds (45 billionths of a second). | | | The new IBM algorithm opens up a whole new range of applications for Reed-Solomon error correction by speeding it up to a level comparable with that of Hamming code error correction. | | | Thanks to their simple error correction processes, Hamming codes can be decoded in parallel, which allows very fast error correction at speeds much greater than 1 Gb/s (a billion bits per second). |
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http://www.research.ibm.com/trl/news/lead_rs_e.htm
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| | Fault tolerant memory using bus bit aligned Reed-Solomon error correction code symbols - Patent 5313464 |
| | This is partly due to the fact that a data bus error or memory device failure can cause the loss of more than one ten bit symbol, thus limiting the effectiveness of the error correction code in protecting the integrity of data blocks. | | | A 640 byte data block comprising 512 ten-bit symbols using the Reed-Solomon error correction code is stored in twenty byte groups of each of thirty-two eight-bit by 128 kilobyte static RAM devices. | | | In order to more effectively utilize simple, single error correcting codes, various data organizations have been adopted that disperse the data such that a single occurrence of an error does not show up as a burst error, thus exceeding the correction capability of the code. |
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http://www.freepatentsonline.com/5313464.html
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| | error correcting memory - FOLDOC Definition |
| | The two types of memory errors in RAM (especially DRAM) are "soft" errors due to radiation-induced bit switching, and "hard" errors due to the unexpected deterioration of a memory chip. | | | Soft errors do not indicate lasting damage to the memory board, but they do corrupt programs or data. | | | Single bit memory failures are the most common. |
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http://www.nightflight.com/foldoc/foldoc.cgi?error+correcting+memory
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