Ray-tracing Based Investigations on the Deployment of RISs in Indoor Scenarios
(2023) EITM02 20231Department of Electrical and Information Technology
- Abstract
- Reconfigurable intelligence surface (RIS) is a promising candidate technology for future 6G wireless communication systems. In existing communication systems, the network operators are unable to control the propagation environment, which causes significant limitations on communication performance. RIS aims to create favorable propagation conditions via programmable phase shifts. Employing RIS can improve power/spectrum efficiency, which improves the quality of communication and reduces costs.
Understanding the trade-offs between the number of base stations (BSs) and the number of RISs is highly desired by both industry and academia. To this end, a ray-tracing-based deterministic indoor channel model is developed. Based on the ray... (More) - Reconfigurable intelligence surface (RIS) is a promising candidate technology for future 6G wireless communication systems. In existing communication systems, the network operators are unable to control the propagation environment, which causes significant limitations on communication performance. RIS aims to create favorable propagation conditions via programmable phase shifts. Employing RIS can improve power/spectrum efficiency, which improves the quality of communication and reduces costs.
Understanding the trade-offs between the number of base stations (BSs) and the number of RISs is highly desired by both industry and academia. To this end, a ray-tracing-based deterministic indoor channel model is developed. Based on the ray tracing simulator, this thesis aims at providing trade-offs between the number of BSs and the number of RISs regarding the received power of user equipment (UE). Ray tracing simulations are made in the Wireless InSite™ software, and data processing in MATLAB™. To investigate the trade-offs, we evaluate the communication performance with different numbers of activated RISs and BSs. Here, our approach is to investigate a large number of tentative deployed BS/RIS positions and constrain the number of activated BS/RIS and the minimum acceptable power threshold at UE. Given the constraints, we optimize over the BS/RIS placements. In total, four optimization problems are solved in this thesis. We will present our mathematical modeling of optimization problems and how we solve them using MATLAB™.
After the completion of the thesis, we conclude that deploying a small number of RISs can reduce the number of BSs in indoor scenarios without any performance loss regarding the received power at UE. Moreover, RIS is more applicable in environments with abundant shadowing objects. Allowing a non-zero outage probability, i.e., dropping some UE positions with bad communication conditions, is verified to improve power efficiency greatly. Lastly, we also show the necessity to optimize the phase shifts of RIS to enhance the RIS performance in a wideband system (Less) - Popular Abstract
- Manipulating natural elements like air and water has been associated with an art called magic. If you are able to control nature by yourself, you are called either a magician or a science fiction character. But what if it was possible to manipulate how electromagnetic waves move in an environment? Maybe not total control but in a way that improves wireless communication from what it is today. This is possible with an emerging technology candidate called reconfigurable intelligent surface (RIS) in the emerging 6G wireless communication standard.
With a RIS, we will be able to control the physical environment to an extent for it to be compared to magic. We have all complained about important calls being cut because the signal quality has... (More) - Manipulating natural elements like air and water has been associated with an art called magic. If you are able to control nature by yourself, you are called either a magician or a science fiction character. But what if it was possible to manipulate how electromagnetic waves move in an environment? Maybe not total control but in a way that improves wireless communication from what it is today. This is possible with an emerging technology candidate called reconfigurable intelligent surface (RIS) in the emerging 6G wireless communication standard.
With a RIS, we will be able to control the physical environment to an extent for it to be compared to magic. We have all complained about important calls being cut because the signal quality has dropped or while we are streaming an exciting science fiction series, the video stops and buffers or mobile operators spending ginormous amounts of money to improve service quality. What if using a RIS we are able to mitigate these issues? Advancements in RIS research show improvements in increasing the range of existing systems, increasing energy efficiency and improving system security.
If so, then how many of these promising products, i.e., RIS, might be needed to see a justifiable improvement in wireless communication in a given scenario? To answer this question, we would need a procedure to find out how to perform this evaluation, mathematical proof backing this method, data-driven results to validate the claims made earlier, and a defined measure of justifiable improvement. Our master thesis on "Ray-tracing Based Investigations on the Deployment of RISs in Indoor Scenarios" answers these questions and opens doors to many other possibilities in using this potentially groundbreaking technology. We encourage the readers to go through our thesis report to understand how we have answered the aforementioned questions using mathematics and simulations with an interesting technique called Ray-tracing. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9125326
- author
- Nambala, Swaroop Divya Sai Prem LU and Kong, Dexin LU
- supervisor
-
- Xuesong Cai LU
- Fredrik Rusek LU
- organization
- course
- EITM02 20231
- year
- 2023
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- Reconfigurable intelligent surface, RIS, optimization, Ray-tracing, Mixed integer linear programming (MILP), Complex impulse response, Wireless Insite.
- report number
- LU/LTH-EIT 2023-930
- language
- English
- id
- 9125326
- date added to LUP
- 2023-06-20 11:37:49
- date last changed
- 2023-06-20 11:37:49
@misc{9125326,
abstract = {{Reconfigurable intelligence surface (RIS) is a promising candidate technology for future 6G wireless communication systems. In existing communication systems, the network operators are unable to control the propagation environment, which causes significant limitations on communication performance. RIS aims to create favorable propagation conditions via programmable phase shifts. Employing RIS can improve power/spectrum efficiency, which improves the quality of communication and reduces costs.
Understanding the trade-offs between the number of base stations (BSs) and the number of RISs is highly desired by both industry and academia. To this end, a ray-tracing-based deterministic indoor channel model is developed. Based on the ray tracing simulator, this thesis aims at providing trade-offs between the number of BSs and the number of RISs regarding the received power of user equipment (UE). Ray tracing simulations are made in the Wireless InSite™ software, and data processing in MATLAB™. To investigate the trade-offs, we evaluate the communication performance with different numbers of activated RISs and BSs. Here, our approach is to investigate a large number of tentative deployed BS/RIS positions and constrain the number of activated BS/RIS and the minimum acceptable power threshold at UE. Given the constraints, we optimize over the BS/RIS placements. In total, four optimization problems are solved in this thesis. We will present our mathematical modeling of optimization problems and how we solve them using MATLAB™.
After the completion of the thesis, we conclude that deploying a small number of RISs can reduce the number of BSs in indoor scenarios without any performance loss regarding the received power at UE. Moreover, RIS is more applicable in environments with abundant shadowing objects. Allowing a non-zero outage probability, i.e., dropping some UE positions with bad communication conditions, is verified to improve power efficiency greatly. Lastly, we also show the necessity to optimize the phase shifts of RIS to enhance the RIS performance in a wideband system}},
author = {{Nambala, Swaroop Divya Sai Prem and Kong, Dexin}},
language = {{eng}},
note = {{Student Paper}},
title = {{Ray-tracing Based Investigations on the Deployment of RISs in Indoor Scenarios}},
year = {{2023}},
}