AR# 11146

DSP Reed Solomon - Can a Xilnix RS encoder/decoder hand a range of codeword lengths?

Description

Keywords: codeword, symbol

Urgency: Standard

General Description:

Can a Xilnix RS encoder/decoder hand a range of codeword lengths?

Solution

Generally the codeword length is fixed at 'n'. Shortened codes just means the
value of 'n' does not need to be 2**(symbol_width)-1. i.e. if the symbol width is 8
then n can be less than 255 but it is still fixed.

In some cases a trick can be used to make the encoder or decoder work for
multiple codeword lengths. If n-k doesn't change and all parameters remain the
same then n can be set to the longest codeword required. When smaller
codewords are required the code word should be pre-pended with zeroes to make
it up to n. So the actual codeword length is still n but it has been padded with
zeroes.
AR# 11146
Date 05/13/2009
Status Archive
Type General Article