Communications Blockset

Integer-Input RS Encoder

Create a Reed-Solomon code from integer vector data

Library

Block sublibrary of Channel Coding

Description

The Integer-Input RS Encoder block creates a Reed-Solomon code with message length K and codeword length N. You specify both N and K directly in the block mask. N must have the form 2^M-1, where M is an integer greater than or equal to 3. The code is more efficient if N-K is an even integer.

The input and output are integer-valued signals that represent messages and codewords, respectively. The integers that form the messages and codewords represent elements of the finite field GF(2^M) and hence must be between 0 and 2^M-1.

The input must contain exactly K elements. If it is frame-based, then it must be a column vector. The output is a vector of length N.

An (N,K) Reed-Solomon code can correct up to floor((N-K)/2) symbol errors (not bit errors) in each codeword.

Examples

Suppose M = 3, N = 2³-1 = 7, and K = 5. Then a message is a vector of length 5 whose entries are integers between 0 and 7. A corresponding codeword is a vector of length 7 whose entries are integers between 0 and 7. The figure below illustrates possible input and output signals to this block, when the block parameters are set to their defaults of 7 and 5, respectively.

Dialog Box

Codeword length N

The codeword length, which is also the output vector length.

Message length K

The message length, which is also the input vector length.

Pair Block

Integer-Output RS Decoder

See Also

Binary-Input RS Encoder

Insert Zero

Integer-Output RS Decoder