Linear codes over Z4+uZ4: MacWilliams identities, projections, and formally self-dual codes
نویسندگان
چکیده
Linear codes are considered over the ring Z 4 + uZ 4 , a non-chain extension of Z 4. Lee weights, Gray maps for these codes are defined and MacWilliams identities for the complete, symmetrized and Lee weight enumer-ators are proved. Two projections from Z 4 + uZ 4 to the rings Z 4 and F 2 + uF 2 are considered and self-dual codes over Z 4 +uZ 4 are studied in connection with these projections. Finally three constructions are given for formally self-dual codes over Z 4 + uZ 4 and their Z 4-images together with some good examples of formally self-dual Z 4-codes obtained through these constructions.
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عنوان ژورنال:
- Finite Fields and Their Applications
دوره 27 شماره
صفحات -
تاریخ انتشار 2014