New classes of cyclic extended Goppa codes
In this correspondence, we give a condition for a "classical" Goppa code to have a cyclic extension. This condition follows from properties of the semilinear automorphism group of the corresponding Generalized Reed-Solomon codes. Using this condition, we can construct not only all the known Goppa codes with a cyclic extension, but also new families.
goppa codes semilinear automorphism groups cyclic codes