When arranging J cyclic permutation matrices I(p j,l ) with p rows and q columns (0≤j≤J-1, 0≤1≤L-1) in a row direction and also arranging L cyclic permutation matrices I (p j,l ) in a column direction so as to generate a regular quasi-cyclic matrix having uniform row and column weights, a quasi-cyclic matrix generating unit 31 configures the regular quasi-cyclic matrix by combining cyclic permutation matrices I(p j,l ) in each of which matrix elements whose row number is r (0≤r≤p-1) and whose column number is (r+p j,l ) mod p are "1"s, and other matrix elements are "0"s in such a way that a plurality of cyclic permutation matrices I(p j,l ) arranged at, e.g., the 1st row differ from one another.