Why does the BCHPOLY function in the Communications Toolbox 2.0.1 (R12.1) return the incorrect parity check matrix?

The BCHPOLY function in the Communications Toolbox 2.0.1 (R12.1) returns the incorrect parity check matrix.

Answer 1

[MathWorks Support Team]

There is a bug in the BCHPOLY function for Communications Toolbox 2.0.1 (R12.1) that generates an incorrect parity check matrix. As a workaround, use the BCHPOLY function to compute the generator polynomial, and the CYCLGEN function to compute the parity check by passing in the generator polynomial as a parameter.

Note that the BCHPOLY function in Communications Toolbox 2.1 (R13) no longer returns a parity check matrix. Hence, the only way to get the parity check matrix would be to use the CYCLGEN function.