ABSTRACT
Error detection and correction plays a very important role in data communication. Various codes such as convolutional and block codes are available for the purpose of error detection and correction. Among the block codes Reed-Solomon code provides several advantages. Reed-Solomon codes are powerful error-correcting codes that finds wide applications in many fields. The soft-decision decoding of Reed-Solomon codes provides reliable information from the channel into the decoding process. Many soft-decision decoding algorithms are available. Among them the Koetter-Vardy algorithm is used in this paper. The gain of soft-decision …show more content…
An important function of any modern digital communications system is error control coding. Such coding in the field of communication deals with techniques for detecting and correcting errors in a signal. Though used in a variety of systems, error control coding is especially useful in wireless communication system. Such systems typically operate with a low signal-to-noise ratio (SNR) and suffer from distortion because of a multipath channel. The harsh wireless environment means that the received signal is prone to …show more content…
Reed-Solomon code
Reed-Solomon are block-based error correcting codes that can be found in many digital communication standards. It finds a wide range of applications in many areas such as storage devices, wireless or mobile communications, satellite communications, digital television, high speed modems.
Fig.1. A typical communication system
The Reed-Solomon encoder takes a block of digital data and adds extra “redundant” bits. Errors occur during transmission or storage for a number of reasons such as noise or interference, scratches on a CD. The Reed-Solomon decoder processes each block and attempts to correct errors and recover the data. The number and type of errors that can be corrected depends on the characteristics of the Reed-Solomon code.
2.1.Properties of Reed-Solomon codes
The Reed-Solomon code is specified as RS(n,k) with s-bit symbols. This means that the encoder takes k data symbols of s bits each and adds parity symbols to make an n symbol codeword. There are n-k parity symbols of s bits each. A Reed-Solomon decoder can correct up to t symbols that contain errors in a codeword, where 2t=n-k[16]. Fig.2. A typical Reed-Solomon code