A Prediction Study of Path Loss Models from 2-73.5 GHz in an Urban-Macro Environment

Abstract

It is becoming clear that 5G wireless systems will encompass frequencies from around 500 MHz all the way to around 100 GHz. To adequately assess the performance of 5G systems in these different bands, path loss (PL) models will need to be developed across this wide frequency range. The PL models can roughly be broken into two categories, ones that have some anchor in physics, and ones that curve-match only over the data set without any physical anchor. In this paper we use both real-world measurements from 2 to 28 GHz and ray-tracing studies from 2 to 73.5 GHz, both in an urban-macro environment, to assess the prediction performance of the two PL modeling techniques. In other words, we look at how the two different PL modeling techniques perform when the PL model is applied to a prediction set which is different in distance, frequency, or environment from a measurement set where the parameters of the respective models are determined. We show that a PL model with a physical anchor point can be a better predictor of PL performance in the prediction sets while also providing a parameterization which is more stable over a substantial number of different measurement sets.

Overview of Millimeter Wave Communications for Fifth-Generation (5G) Wireless Networks—With a Focus on Propagation Models

“…The standard deviation σ yields insight into the statistical variation about the distant-dependent mean path loss [61]. The CI model ties path loss at any frequency to the physical free space path loss at 1 m according to Friis' free space equation [85], and has been shown to be robust and accurate in various scenarios [19], [24], [27], [28]. Indoor environments, however, were found to have frequency-dependent loss beyond the first meter, due to the surrounding environment, and work in [21] extended the CI model to the CIF model where the PLE has a frequency-dependent term.…”

3-D Millimeter-Wave Statistical Channel Model for 5G Wireless System Design

“…The current 3GPP/WINNER path loss models use two parameters to describe path loss over distance (a slope and an intercept), which are highly dependent upon the number of path loss samples measured and corresponding distances. The CI model, however, uses just one parameter, the PLE, making it more stable across various path loss data sets, frequencies, and environments [12], [27], [33], [62], while remaining steeped in physics to a physical free space path loss value at a distance of 1 m, which can always be considered to be within LOS of a BS. Using the CI model, it is therefore easier to compare path loss results from different research groups.…”

“…Users located near BSs (i.e., small TX-RX separation) will be power controlled in the near field [27], [62].…”

“…The d 0 = 1 m CI free space reference path loss model is a simple physically-based one-parameter (PLE) model [12], [33], which is more stable across frequencies and environments than the traditional FI least-squares regression equation line [12], [27], [33], [62]. Further, the CI and FI models perform similarly over identical data sets, with differences in standard deviations that are within a fraction of a dB, yet the CI model is simpler and based on fundamental propagation physics [12], [27], [33].…”

A study of channel model parameters for aerial base stations at 2.4 GHz in different environments

“…In our study we have considered CI free space reference distance PL model as it is a standard approach for describing propagation at any frequency and it is more stable, simple, and reliable than other models such as, for example, ABG model [14], [18]. The model is based on two fundamental parameters, the Path Loss Exponent (PLE) and the standard deviation of fading σ, both dependent on the environment.…”