  A cache-aided $K$-user Gaussian broadcast channel (BC) is considered. The
transmitter has a library of $N$ equal-rate files, from which each user demands
one. The impact of the equal-capacity receiver cache memories on the minimum
required transmit power to satisfy all user demands is studied. Considering
uniformly random demands across the library, both the minimum average power
(averaged over all demand combinations) and the minimum peak power (minimum
power required to satisfy all demand combinations) are studied. Upper bounds
are presented on the minimum required average and peak transmit power as a
function of the cache capacity considering both centralized and decentralized
caching. The lower bounds on the minimum required average and peak power values
are also derived assuming uncoded cache placement. The bounds for both the peak
and average power values are shown to be tight in the centralized scenario
through numerical simulations. The results in this paper show that proactive
caching and coded delivery can provide significant energy savings in wireless
networks.
