  Communication at millimeter wave (mmWave) frequencies is one of the main
novelties introduced in the 5th generation (5G) of cellular networks. The
opportunities and challenges associated with such high frequencies have
stimulated a number of studies that rely on simulation for the evaluation of
the proposed solutions. The accuracy of simulations largely depends on that of
the channel model, but popular channel models for mmWaves, such as the Spatial
Channel Models (SCMs), have high computational complexity and limit the
scalability of the scenarios. This paper profiles the implementation of a
widely-used SCM model for mmWave frequencies, and proposes a simplified version
of the 3GPP SCM that reduces the computation time by up to 12.5 times while
providing essentially the same distributions of several metrics, such as the
Signal-to-Interference-plus-Noise Ratio (SINR) in large scale scenarios. We
also give insights on the use cases in which using a simplified model can still
yield valid results.
