28 GHz Millimeter-Wave Ultrawideband Small-Scale Fading Models in Wireless Channels

摘要

This paper presents small-scale fading measurements for 28 GHz outdoormillimeter-wave ultrawideband channels using directional horn antennas at thetransmitter and receiver. Power delay profiles were measured at half-wavelengthspatial increments over a local area (33 wavelengths) on a linear track in twoorthogonal receiver directions in a typical base-to-mobile scenario with fixedtransmitter and receiver antenna beam pointing directions. The voltage pathamplitudes are shown to follow a Rician distribution, with K-factor rangingfrom 9 - 15 dB and 5 - 8 dB in line of sight (LOS) and non-line of sight (NLOS)for a vertical-to-vertical co-polarized antenna scenario, respectively, andfrom 3 - 7 dB in both LOS and NLOS vertical-to-horizontal cross-polarizedantenna scenario. The average spatial autocorrelation functions of individualmultipath components reveal that signal amplitudes reach a correlation of 0after 2 and 5 wavelengths in LOS and NLOS co-polarized V-V antenna scenarios.The models provided are useful for recreating path gain statistics ofmillimeter-wave wideband channel impulse responses over local areas, for thestudy of multi-element antenna simulations and channel estimation algorithms.