參數(shù)資料
型號(hào)： AN2407
廠商： 飛思卡爾半導(dǎo)體(中國(guó))有限公司
英文描述： Reed Solomon Encoder/Decoder on the StarCore SC140/SC1400 Cores, With Extended Examples
中文描述： 里德所羅門編碼器/的StarCore SC140/SC1400核心解碼器，以擴(kuò)展實(shí)例
文件頁(yè)數(shù)： 3/48頁(yè)
文件大?。?/td> 306K
代理商： AN2407
Theory
Reed Solomon Encoder/Decoder on the StarCore SC140/SC1400 Cores, With Extended Examples, Rev. 1
Freescale Semiconductor
3
The Reed-Solomon codes are block codes. Unlike convolutional codes, Reed-Solomon codes operate on multi-bit
symbols rather than on individual bits. The question of whether to choose convolutional codes or block codes
depends on several variables. In low-speed, low-integrity applications, convolutional codes are the better choice,
and block codes are suitable for high-speed, high-integrity applications. An example of an application suited to
convolutional codes is a digitized voice communication in which a relatively high bit-error rate (about 10
–3
) is
acceptable. For blocks of machine-oriented data in which the desired bit-error rate ranges from 10
–10
to 10
–14
,
block codes are the natural choice. Some applications use both convolutional and block codes. In such applications,
concatenated codes result in strong performance by operating in two steps. The inner decoder, usually
convolutional, reduces the bit-error rate to a medium-low level, and the outer decoder, usually a block type,
reduces the bit-error rate further, to a very low level.
The errors introduced by the communications channel are classified into two main categories:
Random errors
. The bit-error probabilities are independent of each other. For example, thermal noise
in communication channels typically causes random errors.
Burst errors
. The bit errors occur sequentially in time. Burst errors can be caused by such conditions as
a fading communications channel or mechanical defects in a storage system.
When an FEC system is designed, the statistical nature of the noise environment must be considered, as well as the
acceptable output bit-error rate. When the environment consists predominately of random errors, convolutional
codes provide a low bit-error rate solution. However, when the environment has lower bit-error rates, long-length
block codes often perform even better. In burst-error channels, Reed-Solomon codes are among the best codes
because errors composed of many consecutive corrupted bits translate into only a few erroneous symbols.
2
Theory
The Reed-Solomon code was developed in 1960 by I. Reed and G. Solomon [4]. This code is an error detection and
correction scheme based on the use of Galois field arithmetic. This section provides background information on
binary and extended Galois fields and summarizes the essence of the Reed-Solomon codes. For details on Reed-
Solomon codes, consult the literature, for example, [5] and [6].
2.1 Galois Fields
A number field has the following properties:
Both an addition and a multiplication operation that satisfy the commutative, associative, and
distributive laws.
Closure, so that adding or multiplying elements always yields field elements as results.
Both
zero
and
unity
elements. The zero element leaves an element unchanged under addition. The
unity element leaves an element unchanged under multiplication.
An additive/multiplicative inverse for each field element. The sole exception is the zero element,
which has no multiplicative inverse.
Division is defined as the inverse of multiplication such that if
a
×
b
=
c
, it follows that
c
divided by
a
yields
b.
An
example of a number field is the set of real numbers together with the addition and multiplication operations.
Galois fields differ from real number fields in that they have only a finite number of elements. Otherwise, they
share all the properties common to number fields.
相關(guān)PDF資料
PDF描述
AN2410S Video Camera Circuit
AN2441S Color Encoder Circuit
AN246 Transmission lines and terminations with Philips Advanced Logic families
AN2510S Video Camera Circuit
AN2512S Video Camera Circuit
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AN2407FHP 制造商:Panasonic Industrial Company 功能描述:IC
AN241 制造商:Panasonic Industrial Company 功能描述:IC
AN2410S 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Video Camera Circuit
AN2416 制造商:VYNCKIER ENCLOSURE SYSTEMS 功能描述:ENCLOSURE, JUNCTION BOX, POLYESTER BEIGE; Enclosure Type:Junction Box; Enclosure Material:Fiberglass Reinforced Polyester; Body Color:Beige; External Height - Imperial:24.21"; External Height - Metric:615mm; IP Rating:IP66 ;RoHS Compliant: Yes
AN2416PL 制造商:VYNCKIER ENCLOSURE SYSTEMS 功能描述:ENCLOSURE, JUNCTION BOX, POLYESTER BEIGE; Enclosure Type:Junction Box; Enclosure Material:Fiberglass Reinforced Polyester; Body Color:Beige; External Height - Imperial:24.21"; External Height - Metric:615mm; IP Rating:IP66 ;RoHS Compliant: Yes
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*