Hoi Chuen Cheng, Frederick Ziyang Hong, Babar Hussain, Yiru Wang, Chik Patrick Yue^*

CMC-Computers, Materials & Continua, Vol.81, No.1, pp. 161-181, 2024, DOI:10.32604/cmc.2024.053079 - 15 October 2024

Abstract Large-scale indoor 3D reconstruction with multiple robots faces challenges in core enabling technologies. This work contributes to a framework addressing localization, coordination, and vision processing for multi-agent reconstruction. A system architecture fusing visible light positioning, multi-agent path finding via reinforcement learning, and 360° camera techniques for 3D reconstruction is proposed. Our visible light positioning algorithm leverages existing lighting for centimeter-level localization without additional infrastructure. Meanwhile, a decentralized reinforcement learning approach is developed to solve the multi-agent path finding problem, with communications among agents optimized. Our 3D reconstruction pipeline utilizes equirectangular projection from 360° cameras to More >

Mohammed S. M. Gismalla^1,2, Asrul I. Azmi^1,2, Mohd R. Salim^1,2, Farabi Iqbal^1,2, Mohammad F. L. Abdullah³, Mosab Hamdan^4,5, Muzaffar Hamzah^4,*, Abu Sahmah M. Supa’at^1,2

CMC-Computers, Materials & Continua, Vol.77, No.2, pp. 2189-2204, 2023, DOI:10.32604/cmc.2023.035250 - 29 November 2023

Abstract Visible light communication (VLC) has a paramount role in industrial implementations, especially for better energy efficiency, high speed-data rates, and low susceptibility to interference. However, since studies on VLC for industrial implementations are in scarcity, areas concerning illumination optimisation and communication performances demand further investigation. As such, this paper presents a new modelling of light fixture distribution for a warehouse model to provide acceptable illumination and communication performances. The proposed model was evaluated based on various semi-angles at half power (SAAHP) and different height levels for several parameters, including received power, signal to noise ratio More >

Mohammed S. M. Gismalla^1,2,3, Asrul I. Azmi^1,2, Mohd R. Salim^1,2, Farabi Iqbal^1,2, Mohammad F. L. Abdullah⁴, Mosab Hamdan^5,6, Muzaffar Hamzah^5,*, Abu Sahmah M. Supa’at^1,2

CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 3607-3625, 2023, DOI:10.32604/cmc.2023.031192 - 31 October 2022

Abstract Visible light communication (VLC), which is a prominent emerging solution that complements the radio frequency (RF) technology, exhibits the potential to meet the demands of fifth-generation (5G) and beyond technologies. The random movement of mobile terminals in the indoor environment is a challenge in the VLC system. The model of optical attocells has a critical role in the uniform distribution and the quality of communication links in terms of received power and signal-to-noise ratio (SNR). As such, the optical attocells positions were optimized in this study with a developed try and error (TE) algorithm. The More >

Adisorn Kaewpukdee, Peerapong Uthansakul^*

CMC-Computers, Materials & Continua, Vol.74, No.1, pp. 1025-1048, 2023, DOI:10.32604/cmc.2023.032569 - 22 September 2022

Abstract Visible Light Communication (VLC) technology is aggressive research for the next generation of communication. Currently, Radio Frequency (RF) communication has crowed spectrum. An Intelligent Transportation System (ITS) has been improved in the communication network for Vehicle-to-Vehicle (V2 V), Vehicle-to-Infrastructure (V2I), and Infrastructure-to-Vehicle (I2 V) by using the visible light spectrum instead of the RF spectrum. This article studies the characterization of Line-of-Sight (LOS) optical performance in an Outdoor Wireless Visible Light Communication (OWVLC) system employing a Multiple-Input Multiple-Output (MIMO) technique for I2 V communications in ITS regulations. We design the new configuration of the OWVLC-I2 V system, which is More >

R. Priyadharsini^*, A. Kunthavai

Intelligent Automation & Soft Computing, Vol.35, No.1, pp. 261-279, 2023, DOI:10.32604/iasc.2023.025884 - 06 June 2022

Abstract Radio waves and strong magnetic fields are used by Magnetic Resonance Imaging (MRI) scanners to detect tumours, wounds and visualize detailed images of the human body. Wi-Fi and other medical devices placed in the MRI procedure room produces RF noise in MRI Images. The RF noise is the result of electromagnetic emissions produced by Wi-Fi and other medical devices that interfere with the operation of the MRI scanner. Existing techniques for RF noise mitigation involve RF shielding techniques which induce eddy currents that affect the MRI image quality. RF shielding techniques are complex and lead… More >

Xiukai Ruan¹, Shahid Iqbal Awan^2,*

Journal on Internet of Things, Vol.4, No.4, pp. 215-225, 2022, DOI:10.32604/jiot.2022.038270 - 18 July 2023

Abstract A SCMA ACO-OFDM downlink visible light communication (VLC) system is proposed. Six users share four spectrum resources, four of which are 4 primary color LED lights. ACO-OFDM technology is used to convert the user’s sparse codebook mapped signal into a positive real value signal that can be carried on the light wave, which can realize high-speed parallel communication. Simulation verifies the feasibility of the system. At the same time, the channel model of visible light communication is constructed, and the signal-to-noise ratio(SNR) and channel gain of the visible light channel are systematically analyzed. Finally, the More >

Ladathunya Pumkaew, Monthippa Uthansakul^*, Peerapong Uthansakul

CMC-Computers, Materials & Continua, Vol.71, No.1, pp. 1547-1566, 2022, DOI:10.32604/cmc.2022.022556 - 03 November 2021

Abstract Nowadays, Visible Light Communication (VLC) is an attractive alternative technology for wireless communication because it can use some simple Light Emitting Diodes (LEDs) instead of antennas. Typically, indoor VLC is designed to transmit only one dataset through multiple LED beams at a time. As a result, the number of users per unit of time (throughput) is relatively low. Therefore, this paper proposes the design of an indoor VLC system using switched-beam technique through computer simulation. The LED lamps are designed to be arranged in a circular array and the signal can be transmitted through the… More >

K. M. Delphin Raj¹, Sun-Ho Yum¹, Jinyoung Lee², Eunbi Ko³, Soo-Yong Shin², Soo-Hyun Park^3,*

CMC-Computers, Materials & Continua, Vol.70, No.3, pp. 5721-5743, 2022, DOI:10.32604/cmc.2022.020870 - 11 October 2021

Abstract For the past few decades, the internet of underwater things (IoUT) obtained a lot of attention in mobile aquatic applications such as oceanography, diver network monitoring, unmanned underwater exploration, underwater surveillance, location tracking system, etc. Most of the IoUT applications rely on acoustic medium. The current IoUT applications face difficulty in delivering a reliable communication system due to the various technical limitations of IoUT environment such as low data rate, attenuation, limited bandwidth, limited battery, limited memory, connectivity problem, etc. One of the significant applications of IoUT include monitoring underwater diver networks. In order to… More >

Lukas Danys¹, Radek Martinek¹, Rene Jaros^1,*, Jan Baros¹, Petr Simonik², Vaclav Snasel³

CMC-Computers, Materials & Continua, Vol.68, No.3, pp. 3629-3652, 2021, DOI:10.32604/cmc.2021.017333 - 06 May 2021

Abstract This pilot study focuses on a real measurements and enhancements of a software defined radio-based system for vehicle-to everything visible light communication (SDR-V2X-VLC). The presented system is based on a novel adaptive optimization of the feed-forward software defined equalization (FFSDE) methods of the least mean squares (LMS), normalized LMS (NLMS) and QR decomposition-based recursive least squares (QR-RLS) algorithms. Individual parameters of adaptive equalizations are adjusted in real-time to reach the best possible results. Experiments were carried out on a conventional LED Octavia III taillight drafted directly from production line and universal software radio peripherals (USRP)… More >