Fading Evaluation in the mm-Wave Band

Abstract

A thorough millimeter-wave measurement campaign is carried out in an indoor environment with an aim at characterizing the short-term fading channel behavior. The measurements are conducted in a variety of scenarios, with frequencies ranging from 55 GHz to 65 GHz, in line-of-sight and nonline-of-sight conditions, and combinations of horizontal and vertical polarizations at both transmitter and receiver. A number of fading models are tested, namely Rayleigh, Rice, Nakagami-m, α-µ, κ-µ, η-µ, and α-η-κ-µ. The statistics under analysis are those characterizing the fading amplitude and the frequency selectivity. In particular, the probability density and cumulative distribution functions for the former and level crossing rate per bandwidth unit for the latter are the respective first-and second-order statistics used. To this end, from the experimental data, the parameters of the models are estimated and the corresponding theoretical curves are plotted and compared with the empirical ones. Whereas the required theoretical formulations of the first-order statistics of these models are already well known, those of the second-order statistics as well as these fitting process in such a band shown here are unprecedented in the literature.

Fading Channel Models for mm-Wave Communications

“…Specifically, measurement campaigns were carried out in various indoor mm-Wave scenarios with frequencies ranging from 55 to 65 GHz for LOS and NLOS conditions. The findings in [19] reveal that the α-µ, η-µ, and κ-µ fading channel models are satisfactory for modeling short-term fading in the mm-Wave band. Other interesting results for modeling small-scale fading in mm-Wave communications can be found in [20][21][22].…”

“…Here, by substituting ( 20) into (19), and then by truncating the resulting expression up to the first T 2 terms, we get…”

“…The TWDP channel model has also successfully been applied in recent publications to model vehicle-to-infrastructure channel measurement data in the mm-Wave band [17,18]. Recently, other popular stochastic fading models were investigated in [19] to characterize propagation conditions encountered in mm-Wave communications. Specifically, measurement campaigns were carried out in various indoor mm-Wave scenarios with frequencies ranging from 55 to 65 GHz for LOS and NLOS conditions.…”

Fading Evaluation in Standardized 5G Millimeter-Wave Band

“…As already mentioned, the fading models under test are Rayleigh, Rice, Nakagami, α-µ, κ-µ, FN, η-µ, and α-η-κ-µ. The expressions of their first-order statistics, namely PDF, as well as the description of the corresponding parameters can be found in [21]. In the same way, the expressions of their second-order statistics, namely LCR, as well as the description of the corresponding parameters can be found in [22].…”

“…Therefore, it is practically impossible to have a single combination of distributions parameters that will categorically describe the channel. In general, the environments are rather complex and there is no single or simple solution either in physical or mathematical terms in channel modeling [21].…”