Quotients of Orders in Cyclic Algebras and Space-Time Codes
arXiv:1210.7044
Abstract
Let be a number field with ring of integers $\Oc_F$ and $\Dc$ a division -algebra with a maximal cyclic subfield . We study rings occurring as quotients of a natural $\Oc_F$-order in $\Dc$ by two-sided ideals. We reduce the problem to studying the ideal structure of $Λ/\qf^sΛ$, where $\qf$ is a prime ideal in $\Oc_F$, . We study the case where $\qf$ remains unramified in , both when and . This work is motivated by its applications to space-time coded modulation.