Universal Path Gain Laws for Common Wireless Communication Environments

TL;DR

This paper derives universal, accurate path gain models for various wireless environments based on electromagnetic fundamentals, outperforming existing models and providing theoretical justification for empirical power laws with minimal environmental data.

Contribution

It introduces universal path gain laws applicable across diverse environments, grounded in electromagnetic theory, with simplified parameters and improved accuracy over existing models.

Findings

Root Mean Square errors under 5 dB, better than 3GPP models

Path gain follows a power law with exponents 1.5 to 4

Models outperform linear fits and 3GPP models in urban canyons

Abstract

Simple and accurate expressions for path gain are derived from electromagnetic fundamentals in a wide variety of common environments, including Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) indoor urban canyons, urban/rural macro, outdoor-indoor and suburban streets with vegetation. Penetration into a scattering region, sometimes aided by guiding, is the "universal" phenomenon shared by the diverse morphologies. Root Mean Square (RMS) errors against extensive measurements are under 5 dB, better than 3GPP models by 1-12 dB RMS, depending on environment. In urban canyons the models have 4.7 dB RMS error, as compared to 7.9 dB from linear fit to data and 13.9/17.2 dB from LOS/NLOS 3GPP models. The theoretical path gains depend on distance as a power law with exponents from a small set {1.5, 2, 2.5, 4}, specific to each morphology. This provides a theoretical justification for widely used power law empirical models. Only coarse environmental data is needed as parameters: street width, building height, vegetation depth, wall material and antenna heights.