reed solomon code (RS)

The Reed-Solomon code( RS) is an error correction method used in mobile communications for Cellular Digital Packet Data( CDPD), in wireline communications for ADSL and ATM, and also for data storage on compact discs(CDs) and DVDs.

The Reed-Solomon code is a forward error correction( FEC) method that allows correction of erroneously transmitted data blocks. The FEC data is appended to the user data in a code word in a data block and transmitted together with it. The code word consists of the user data and a number of Reed-Solomon check bytes as well as one or more DMT symbols. If the RS code was selected with 255/239, this means that for each 239 data bytes, an additional 16 bytes are added for the forward error correction (FEC).

The mathematical description is similar to that of the CRC method with cyclic block checking, whereby a previously formed Reed-Solomon check digit is used for polynomial division. For use in compact discs ( CD), the procedure was modified to the CIRC procedure.