Model for Ray-Based UTD Simulations of the Human Body Shadowing Effect in 5G Wireless Systems

Łukasz Januszkiewicz

doi:10.1155/2018/9084830

Abstract

Shadowing effects caused by the obstructing presence of a human body can result in increased path loss in indoor wireless systems. This paper proposes a simplified model of a human body for use in ray-tracing simulations of indoor wireless communication systems based on the uniform theory of diffraction (UTD). The human body shadowing effect was first investigated using measurements and computer simulations employing the finite-difference time-domain method (FDTD). Based on the results, a human body model was elaborated for use in ray-based Remcom XGtd software. The model was developed for the 3.6 GHz band, which has been allocated for 5G wireless systems in many countries.

Highlights

Wireless systems used for personal communication utilize a wide range of frequency bands, from 800 MHz to 6 GHz
The analyses presented in this paper utilize the NMR Hershey model, which is accessible in XFdtd software in several versions, with voxel sizes varying from 1 mm to 10 mm
For the frequency of interest, 3.6 GHz, it was possible to simulate path loss for distances of only a few meters from the human body. This is too small a region to model the path loss in modern wireless systems, which operate at much larger distances, from few tens of meters to kilometers

Summary

Introduction

Wireless systems used for personal communication utilize a wide range of frequency bands, from 800 MHz to 6 GHz. There are important considerations for the designers of wireless systems operating in this range in close proximity to people. The absorption of electromagnetic energy can, have a significant influence on path loss between the wireless transceivers. The impedance and radiation patterns of the antennas may be affected by proximity to a human body. Designers of personal cellular communication systems, in which the transmitted power of the portable terminals reaches several watts, have focused mainly on analysis of the specific absorbance rate (SAR) and the influence of the human body on antenna properties. For designers of wireless sensor networks, which utilize low-power miniature transceivers located on the body, path loss is a more important factor

Methods

Results

Conclusion