Indoor 5G network gets much-needed signal boost

An easy-to-use system consisting of modules that can route 5G around obstacles in the home with the goal of eliminating telecom shadowing areas.

As the Internet has become an indispensable part of our daily lives, the fifth generation of the Internet, or 5G, has offered higher data speeds, increased availability, easier access, higher reliability, and a more consistent experience for users than even its predecessor, 4G.

With the continued wide spread of 5G, this new generation of the Internet is facing some obstacles that hold it back. This is because 5G technology operates in frequency bands below 6 GHz, which leads to various problems not found in current 4G technology, which uses higher frequency bands.

One such reason is the fact that 5G is often limited inside buildings, such as homes and offices, where the electromagnetic waves it carries struggle to penetrate obstructions such as walls, doors, furniture and even humans. This leads to connectivity shadowing areas that hinder 5G indoors.

The solution to this could be the introduction of multiple units to “bounce” electromagnetic surfaces around indoor environments, but this can result in the need for hundreds or thousands of active components, making this an expensive solution. Multiple units complicate the design of 5G Wi-Fi systems and can distort the signal.

All of these factors limit the commercial use of these systems.

Reconfigurable intelligent surface systems (RIS) consisting of modules that can be oriented to avoid obstructions and eliminate communication shadow areas are a promising emerging candidate for solving current indoor 5G communications problems.

A new paper published in the journal advanced intelligent systems He proposes a new mechanism for controlling the electromagnetic wave of RIS by mechanically rotating each unit.

This approach results in a RIS that can combat the shadowing of 5G communications while still being relatively inexpensive, containing few components, and thus remaining simple in design.

“The main findings of the research are new electromechanical tuning mechanisms for RIS applications,” said Sungjoon Lim, co-author and professor at the School of Electrical and Electronic Engineering at Chung-Ang University in Seoul, Korea. “Our findings provide innovative electromagnetic beam control functionality through rotatable unit cell structures and rack gear systems.”

Bringing 5G home

To control the angle of rotation of each unit cell, the mechanical rack gear structure is driven by a single direct current (DC) motor. “Our approach does not require expensive active ingredients and the number of controllers can be reduced,” Lim said.

The team called their proposed system “electromechanically reconfigurable smart surfaces,” or RIS (MRIS). “In addition, it can overcome design complexity, implementation difficulty with bias lines, and modified signal distortion that characterized previous RIS efforts,” Lim added.

Users can remotely control the setting function with a mobile phone, reflecting the 5G beam by driving the units mechanically.

The team tested the internal 5G performance of their proposed system using theoretical analysis and numerical study and also experimentally in a custom built indoor environment.

Thus, the team demonstrated the RIS (MRIS) platform that can be used to solve the signal blocking problem of 5G intercom with the system demonstrating functions such as reflection, scanning and signal scattering depending on the angle of rotation of individual units.

Lim explained what’s next for the system, saying the team intends to expand it from beam control in just two dimensions to more complex beam control in 3D.

“We designed RIS to control each shaft as a proof of concept in this work, and the proposed concept for RIS 3D beam control can be developed,” the researcher said. “We are currently working on 3D beam control RIS.

“In addition, it is necessary to research high-speed DC motors and electrical systems capable of providing constant power to the motors to improve tuning speed.”

Lim said the team also plans to test electromagnetic beams of different polarizations, which is essential because in a home environment, the beams will strike units from multiple paths.

Reference: Heijun. Jeong et al Reconfigurable smart 5th generation wireless mechatronics on the inner surfaceAdvanced Intelligent Systems (2022). DOI: 10.1002 / aisy.202200185