  Future wireless networks will extensively rely upon bandwidths centered on
carrier frequencies larger than 10GHz. Indeed, recent research has shown that,
despite the large path-loss, millimeter wave (mmWave) frequencies can be
successfully exploited to transmit very large data-rates over short distances
to slowly moving users. Due to hardware complexity and cost constraints,
single-carrier modulation schemes, as opposed to the popular multi-carrier
schemes, are being considered for use at mmWave frequencies. This paper
presents preliminary studies on the achievable spectral efficiency on a
wireless MIMO link operating at mmWave in a typical 5G scenario. Two different
single-carrier modem schemes are considered, i.e. a traditional modulation
scheme with linear equalization at the receiver, and a single-carrier
modulation with cyclic prefix, frequency-domain equalization and FFT-based
processing at the receiver. Our results show that the former achieves a larger
spectral efficiency than the latter. Results also confirm that the spectral
efficiency increases with the dimension of the antenna array, as well as that
performance gets severely degraded when the link length exceeds 100 meters and
the transmit power falls below 0dBW. Nonetheless, mmWave appear to be very
suited for providing very large data-rates over short distances.
