  This paper presents 28 GHz and 73 GHz empirically-derived large-scale and
small-scale channel model parameters that characterize average temporal and
angular properties of multipaths. Omnidirectional azimuth scans at both the
transmitter and receiver used high gain directional antennas, from which global
3GPP modeling parameters for the mean global azimuth and zenith spreads of
arrival were found to be 22 degrees and 6.2 degrees at 28 GHz, and 37.1 degrees
and 3.8 degrees at 73 GHz, respectively, in non-line of sight (NLOS).
Small-scale spatial measurements at 28 GHz reveal a mean cross-polar ratio for
individual multipath components of 29.7 dB and 16.7 dB in line of sight and
NLOS, respectively. Small-scale parameters extracted using the KPowerMeans
algorithm yielded on average 5.3 and 4.6 clusters at 28 GHz and 73 GHz,
respectively, in NLOS. The time cluster - spatial lobe (TCSL) modeling approach
uses an alternative physically-based binning procedure and recreates 3GPP model
parameters to generate channel impulse responses, as well as new parameters
like the RMS lobe angular spreads useful in quantifying millimeter-wave
directionality. The TCSL algorithm faithfully reproduces first- and
second-order statistics of measured millimeter-wave channels.
