  We investigate retransmission permutation arrays (RPAs) that are motivated by
applications in overlapping channel transmissions. An RPA is an $n\times n$
array in which each row is a permutation of ${1, ..., n}$, and for $1\leq i\leq
n$, all $n$ symbols occur in each $i\times\lceil\frac{n}{i}\rceil$ rectangle in
specified corners of the array. The array has types 1, 2, 3 and 4 if the stated
property holds in the top left, top right, bottom left and bottom right
corners, respectively. It is called latin if it is a latin square. We show that
for all positive integers $n$, there exists a type-$1,2,3,4$ $\RPA(n)$ and a
type-1,2 latin $\RPA(n)$.
