  In this paper, we consider a device-to-device communication network in which
$K$ transmitter-receiver pairs are sharing spectrum with each other. We propose
a novel but simple binary scheduling scheme for this network to maximize the
average sum rate of the pairs. According to the scheme, each receiver predicts
its Signal-to-Interference-plus-Noise Ratio (SINR), assuming \emph{all} other
user pairs are active, and compares it to a preassigned threshold to decide
whether its corresponding transmitter to be activated or not. For our proposed
scheme, the optimal threshold that maximizes the expected sum rate is obtained
analytically for the two user-pair case and empirically in the general $K$
user-pair case. Simulation results reveal that our proposed SINR-threshold
scheduling scheme outperforms ITLinQ \cite{navid}, FlashLinQ \cite{flash} and
the method presented in \cite{G} in terms of the expected sum rate (network
throughput). In addition, the computational complexity of the proposed scheme
is $O(K)$, outperforming both ITLinQ and FlashLinQ that have $O(K^2)$
complexity requirements. Moreover, we also discuss the application of our
proposed new scheme into an operator-assisted cellular D2D heterogeneous
network.
