Ramanababu Challapalli, Chitra Perumal, S. Ramana Kumar Joga, Chidurala Saiprakash, Theophilus A. T. Kambo Jr
{"title":"DMIMO and Machine Learning Techniques for Enhanced BER and Data Rates in 5G Free-Space Optical Communication","authors":"Ramanababu Challapalli, Chitra Perumal, S. Ramana Kumar Joga, Chidurala Saiprakash, Theophilus A. T. Kambo Jr","doi":"10.1049/ote2.70018","DOIUrl":"10.1049/ote2.70018","url":null,"abstract":"<p>This paper proposes a dual-MIMO (DMIMO) free-space optical (FSO) communication system integrated with hybrid machine learning models (CNN and LSTM) to enhance bit error rate (BER), Q-factor, and data rates for 5G backhaul networks under atmospheric disturbances. Using OptiSystem software, we simulated the system's performance in fog, rain, haze, and snow environments. Results demonstrate data rates up to 120 Gbps and up to 80% BER improvement compared to conventional MIMO systems, especially under dense fog and turbulence. Although the proposed system shows excellent performance in both simulated conditions and also in experimental validation, real-world challenges such as sudden weather changes, pointing errors, and computational complexity were tested in both simulation and experimental environment. Future work will focus on implementing adaptive beam steering to enhance its validation in real-world situations to optimise the system for dynamic environments.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"19 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70018","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144881324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Miguel Rêgo, Alexis A. Dowhuszko, Pedro Fonseca, Luís Nero Alves
{"title":"Experimental Demonstration of 32-PAM Optical Camera Communication Using a Low Cost and a High Cost Camera","authors":"Miguel Rêgo, Alexis A. Dowhuszko, Pedro Fonseca, Luís Nero Alves","doi":"10.1049/ote2.70016","DOIUrl":"10.1049/ote2.70016","url":null,"abstract":"<p>This work demonstrates experimentally the feasibility of using up to 32-PAM in rolling shutter based optical camera communication (OCC). Two different cameras have been used for OCC performance comparison, namely, a low-cost Pi Camera V2.1 and a higher-cost Alvium 1800 U-500m. Based on the limitations evidenced by this analysis, a decoding algorithm has been proposed to recover the transmitted signal from the acquired images. The experimental evaluation has been carried out for distances up to 2 m, using 8-PAM, 16-PAM and 32-PAM, analysing the received samples histograms and the symbol error rate (SER) for both cameras. Based on the collected experimental results, it is concluded that 32-PAM is possible with both cameras, with a maximum SER of 0.16% for the Alvium camera and 5.05% for the Pi Camera. Finally, it is observed that both the signal and noise amplitudes remain constant for the tested distances, resulting in a SER that does not notably depend on the distance between the transmitter and receiver.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"19 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oğuzhan Başer, Mehmet Ali Küçük, Cenk Albayrak, Kadir Türk
{"title":"Energy-Efficient 8-PAM Optical DAC Design for Visible Light Communication Systems","authors":"Oğuzhan Başer, Mehmet Ali Küçük, Cenk Albayrak, Kadir Türk","doi":"10.1049/ote2.70017","DOIUrl":"10.1049/ote2.70017","url":null,"abstract":"<p>This paper presents a cost-effective and energy-efficient optical digital-to-analog converter (ODAC) transmitter scheme for visible light communication (VLC) systems. The proposed ODAC transmitter enables data transmission while providing lighting, as desired in VLC systems, unlike existing ODAC structures in the literature, by switching power LEDs at high speeds with a MOSFET-based switching circuit design. This paper also discusses the ODAC design stages and presents the points to be considered in detail. In addition, by implementing the hardware design of an ODAC transmitter with a 3-bit resolution, that is, capable of generating 8-PAM signals, based on the proposed ODAC architecture, experimental studies are conducted for energy efficiency and communication performance results via the established VLC system using the designed ODAC. Experimental results demonstrate that the proposed ODAC transmitter achieves a data transmission rate of 18.75 Mbps with a bit error rate (BER) below the forward error correction (FEC) limit at a communication distance of 4 m, while also exhibiting a high power efficiency of 94%.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"19 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Deep Learning Based Design of Binary Signalling for Optical Wireless Communication Systems With 2D Receiver","authors":"Yongwoon Hwang, Chung Ghiu Lee, Soeun Kim","doi":"10.1049/ote2.70015","DOIUrl":"10.1049/ote2.70015","url":null,"abstract":"<p>Recently, deep learning (DL) techniques have been increasingly applied to communication system design, owing to their powerful capabilities in handling complex channel characteristics. We apply a DL technique to binary signalling design for optical wireless communication system, which incorporates a <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>2</mn>\u0000 <mo>×</mo>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 <annotation> $2times 2$</annotation>\u0000 </semantics></math> light-emitting diode (LED) transmitter array. The <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>2</mn>\u0000 <mo>×</mo>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 <annotation> $2times 2$</annotation>\u0000 </semantics></math> LED transmitter array is adopted for two-dimensional (2D) arrayed photodiode receiver. The system encodes binary bit streams into <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>2</mn>\u0000 <mo>×</mo>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 <annotation> $2times 2$</annotation>\u0000 </semantics></math> LED lighting patterns and the 2D received lighting patterns are interpreted as 2D images, which are decoded for retrieving the binary bit stream. For conventional on-off keying (OOK) signal for optical wireless communication system, it is necessary to choose appropriate 2D lighting patterns to represent binary logic symbols effectively. In this paper, we propose a design algorithm for binary signalling to generate appropriate 2D binary symbols. The DL-based signalling design algorithm is implemented as an autoencoder (AE) structure. It is trained with the set of transmitted and received signal patterns over the physical channel model with additive noise. To validate the proposed signalling design scheme, we adopt a two-step approach. Firstly, the signalling design algorithm generates binary LED signal sets after appropriate training processes. Secondly, from the generated signal sets, the LED patterns of interest are investigated considering their symbol error rate (SER) performance. It is confirmed that the proposed design algorithm provides binary signalling sets that meet the required SER performance. Through this study, it is demonstrated that DL-based signalling design is feasible, and the results are expected to contribute to further research aimed at extending the approach to more practical and complex system scenarios.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"19 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144714821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dynamically Tunable Plasmonic Dual-Band Metamaterial Absorber Utilising VO2/MoS2 for Optical Communication Frequencies","authors":"Masoud Hasankhani, Hamid Vahed, Mohammad Bemani","doi":"10.1049/ote2.70009","DOIUrl":"10.1049/ote2.70009","url":null,"abstract":"<p>This paper presents the design and analysis of a tunable metamaterial absorber based on the combination pattern of two-dimensional molybdenum disulfide (MoS<sub>2</sub>) and vanadium dioxide (VO<sub>2</sub>) resonator. The design of the absorber structure is simple and includes an array of silicon on which the pattern of MoS<sub>2</sub> and vanadium is placed. By using the ability to adjust the MoS<sub>2</sub> carrier concentration and VO<sub>2</sub> phase transition properties, the absorber has dual control over its optical properties through temperature and voltage settings. This design provides the possibility of dynamic control of the resonance frequencies of the absorber. The absorber structure shows 99.3% absorption at 1375.8 nm and 94.3% at 1550.9 nm. By adjusting the parameters of the absorber structure, the absorption peak at wavelengths 1545.6 and 1743 nm reached 99.4% and 95.4%, respectively. The tunability of MoS<sub>2</sub> and vanadium allows precise tuning of absorption peak locations and makes the structure suitable for applications such as sensors, detectors, optical filters and telecommunication devices that require precise wavelength placement.</p>","PeriodicalId":13408,"journal":{"name":"Iet Optoelectronics","volume":"19 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/ote2.70009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144688082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}