  This paper studies a wireless network consisting of multiple
transmitter-receiver pairs where interference is treated as noise. Previously,
the throughput region of such networks was characterized for either one time
slot or an infinite time horizon. We aim to fill the gap by investigating the
throughput region for transmissions over a finite time horizon. Unlike the
infinite-horizon throughput region, which is simply the convex hull of the
throughput region of one time slot, the finite-horizon throughput region is
generally non-convex. Instead of directly characterizing all achievable
rate-tuples in the finite-horizon throughput region, we propose a metric termed
the rate margin, which not only determines whether any given rate-tuple is
within the throughput region (i.e., achievable or unachievable), but also tells
the amount of scaling that can be done to the given achievable (unachievable)
rate-tuple such that the resulting rate-tuple is still within (brought back
into) the throughput region. Furthermore, we derive an efficient algorithm to
find the rate-achieving policy for any given rate-tuple in the finite-horizon
throughput region.
