  The capacity region of the one-sided Gaussian interference channel is
established in the weak interference regime. To characterize this region, a new
representation of the Han-Kobayashi inner bound for the one-sided Gaussian
interference channel is first given. Next, a new outer bound on the capacity
region of this channel is introduced which is tight in the weak interference
regime. This is the first capacity region for any variant of the interference
channel in the weak interference regime.
