  Given the overcrowding in the 300 MHz-3 GHz spectrum, millimeter wave
(mmWave) spectrum is a promising candidate for the future generations of
wireless networks. With the unique propagation characteristics at mmWave
frequencies, one of the fundamental questions to address is whether mmWave
networks are noise or interference-limited. The regime in which the network
operates significantly impacts the MAC layer design, resource allocation
procedure and also interference management techniques. In this paper, we first
derive the statistical characteristic of the cumulative interference in
finite-sized mmWave networks considering configuration randomness across
spatial and spectral domains while including the effect of blockages.
Subsequently, using the derived interference model we set up a likelihood ratio
test (LRT) (that is dependent on various network parameters) in order to detect
the regime of the network from an arbitrarily located user standpoint. Unlike
traditional networks, in mmWave networks, different likelihood of experiencing
an interference-limited regime can be observed at different locations.
