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Power Focusing with Intelligent Reflective Surfaces for Wireless Indoor Communication Systems

Gong, Mingye LU (2021) EITM02 20201
Department of Electrical and Information Technology
Abstract
Intelligent reflective surfaces (IRS) are envisioned to have a significant number of applications in future wireless network systems by reconfiguring the signal propagation to improve system performance. In particular, the IRS's cell elements can independently reflect the incident signal by tuning its phase and achieving passive beamforming to enhance the received signal of the user equipment. We study the IRS-aided point to point multiple-input single-output (MISO) wireless system where one IRS is deployed to assist the wireless communication network from a multi-antenna base station to a single-antenna user. The user receives the signal transmitted directly from the base station as well as that reflected by the IRS. We aim to maximize... (More)
Intelligent reflective surfaces (IRS) are envisioned to have a significant number of applications in future wireless network systems by reconfiguring the signal propagation to improve system performance. In particular, the IRS's cell elements can independently reflect the incident signal by tuning its phase and achieving passive beamforming to enhance the received signal of the user equipment. We study the IRS-aided point to point multiple-input single-output (MISO) wireless system where one IRS is deployed to assist the wireless communication network from a multi-antenna base station to a single-antenna user. The user receives the signal transmitted directly from the base station as well as that reflected by the IRS. We aim to maximize the total received signal power at the user by jointly optimizing the (active) transmit beamforming at the base station and (passive) reflect beamforming by the IRS's reflective cells. First, we propose a signal model for the passive IRS-aided wireless network for empty-room and dead-zone scenarios. Second, we propose a beamforming optimization algorithm to analyze the received signal power's maximization for the given scenarios. The performance of the proposed methods is analyzed in an ideal indoor environment where all the antennas both in the base station and the IRS are in a perfect line-of-sight propagation environment. Furthermore, numerical results show significant performance enhancement with the use of IRS in typical wireless networks compared to benchmark schemes. The numerical results show how the IRS-aided wireless system compensates for the attenuation loss blocking by the obstacle wall with different materials in the dead-zone scenarios. Moreover, we present the relationship between the size of the IRS and the received signal power and the size of the IRS and the IRS deploying positions, respectively. It is verified that the IRS can drastically enhance the link quality and coverage over the traditional setup without the IRS. (Less)
Popular Abstract
Intelligent Reflecting surface(IRS) is a brand-new concept providing a revolutionizing technology in wireless communication that will improve the communication network in 6th generation (6G) and beyond wireless networks significantly. The IRS is an artificial meta-surfaces that can control the electromagnetic field on the entire surface, adapt reflecting signals, and proactively modify the wireless channel. The main advantage of IRS technology is that it enables transmitted power, focusing on a target location while reducing interference to its neighbors. This capability, can, logically, be translated into a significant increase in transmission data rates, without an unrealistic increase in transmission power. All the above advantageous... (More)
Intelligent Reflecting surface(IRS) is a brand-new concept providing a revolutionizing technology in wireless communication that will improve the communication network in 6th generation (6G) and beyond wireless networks significantly. The IRS is an artificial meta-surfaces that can control the electromagnetic field on the entire surface, adapt reflecting signals, and proactively modify the wireless channel. The main advantage of IRS technology is that it enables transmitted power, focusing on a target location while reducing interference to its neighbors. This capability, can, logically, be translated into a significant increase in transmission data rates, without an unrealistic increase in transmission power. All the above advantageous make IRS an appealing solution for performance enhancement in next generation wireless networks, especially for indoor environments with a high density of users (e.g. shopping malls, airports, stadiums). Moreover, IRS has excellent compatibility with existing conventional networks, that is, in existing networks, IRS can be flexibly deployed to enhance the performance of current communication networks. IRS also possesses appealing advantages from the implementation aspect, such as lightweight, conformal geometry, and low-cost. However, at this time, the IRS technology is at an infancy stage, and much more research is needed before it can be deployed in practical systems.

The aims of the thesis are analyzing and maximizing the total received signal power at the user equipment by jointly optimizing the (active) transmit beamforming at the base station and (passive) reflect beamforming by the reflective cells at the IRS. For simplicity, we focus on a single user Multiple-Input-Single-Output (MISO) communication system, aided by an IRS comprising passive reflecting element cells.

This thesis can be divided into two parts. In the first part of the thesis, we present a general view of the received power distribution in the empty-room scenario with different deploying positions. In the second part of the thesis, we focus on analyzing how IRS compensates for the power attenuation caused by the obstacle blocking the direct signal propagation link between the base station and the user equipment and how the size and the deploying position of the IRS influence the results. (Less)
Please use this url to cite or link to this publication:
author
Gong, Mingye LU
supervisor
organization
course
EITM02 20201
year
type
H2 - Master's Degree (Two Years)
subject
keywords
Intelligent Reflective Surfaces (IRS), 6G, MISO, Wireless Indoor Communication Systems
report number
LU/LTH-EIT 2021-811
language
English
id
9054427
date added to LUP
2021-06-18 15:06:26
date last changed
2021-06-18 15:06:26
@misc{9054427,
  abstract     = {{Intelligent reflective surfaces (IRS) are envisioned to have a significant number of applications in future wireless network systems by reconfiguring the signal propagation to improve system performance. In particular, the IRS's cell elements can independently reflect the incident signal by tuning its phase and achieving passive beamforming to enhance the received signal of the user equipment. We study the IRS-aided point to point multiple-input single-output (MISO) wireless system where one IRS is deployed to assist the wireless communication network from a multi-antenna base station to a single-antenna user. The user receives the signal transmitted directly from the base station as well as that reflected by the IRS. We aim to maximize the total received signal power at the user by jointly optimizing the (active) transmit beamforming at the base station and (passive) reflect beamforming by the IRS's reflective cells. First, we propose a signal model for the passive IRS-aided wireless network for empty-room and dead-zone scenarios. Second, we propose a beamforming optimization algorithm to analyze the received signal power's maximization for the given scenarios. The performance of the proposed methods is analyzed in an ideal indoor environment where all the antennas both in the base station and the IRS are in a perfect line-of-sight propagation environment. Furthermore, numerical results show significant performance enhancement with the use of IRS in typical wireless networks compared to benchmark schemes. The numerical results show how the IRS-aided wireless system compensates for the attenuation loss blocking by the obstacle wall with different materials in the dead-zone scenarios. Moreover, we present the relationship between the size of the IRS and the received signal power and the size of the IRS and the IRS deploying positions, respectively. It is verified that the IRS can drastically enhance the link quality and coverage over the traditional setup without the IRS.}},
  author       = {{Gong, Mingye}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Power Focusing with Intelligent Reflective Surfaces for Wireless Indoor Communication Systems}},
  year         = {{2021}},
}