Article
Optics
Haiping Song, Chuanming Huang, Hongyu Li, Longquan Dai, Ziqi Liu, Yu Yang, Mengfan Cheng, Qi Yang, Ming Tang, Deming Liu, Lei Deng
Summary: An asymmetric dual-single-sideband modulation scheme for photonic co-frequency millimeter-wave signals generation and a DSP-free receiver are experimentally demonstrated. By modulating two vector-modulated signals and two unmodulated sidebands on asymmetric sides of an optical carrier, sideband crosstalk is effectively avoided without requiring digital compensation algorithms.
Article
Computer Science, Hardware & Architecture
Meilong Jiang, Juergen Cezanne, Ashwin Sampath, Ori Shental, Qiang Wu, Ozge Koymen, Ahmed Bedewy, Junyi Li
Summary: Wireless networks using millimeter-wave and higher band radio enable higher capacity, lower latency, and massive connections. Wireless fronthaul, as an alternative to fiber-based fronthaul, offers flexibility, scalability, and cost advantages. However, it also poses challenges in reliably delivering required performance indicators.
IEEE WIRELESS COMMUNICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Luis Vallejo, Jose Mora, Dong-Nhat Nguyen, Jan Bohata, Vicenc Almenar, Stanislav Zvanovec, Beatriz Ortega
Summary: This paper evaluates local and remote photonic millimeter wave signal generation schemes for practical deployment in a cloud radio access network. The remote configuration leads to higher electrical output power in the mmW band, and also shows superior performance in transmission experiments with QPSK signals.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Sandra Lagen, Xavier Gelabert, Andreas Hansson, Manuel Requena, Lorenza Giupponi
Summary: There is a widely held belief that future radio access network architectures will be characterized by increased levels of virtualization, enhancing performance and reducing deployment costs. In order to cope with the performance requirements of fronthaul links, different compression control strategies and techniques can be used to reduce data rates.
IEEE COMMUNICATIONS MAGAZINE
(2022)
Article
Chemistry, Multidisciplinary
Ramon Maia Borges, Celso Henrique de Souza Lopes, Eduardo Saia Lima, Marco Aurelio de Oliveira, Matheus Seda Borsato Cunha, Luciano Camilo Alexandre, Luis Gustavo da Silva, Luiz Augusto Melo Pereira, Danilo Henrique Spadoti, Murilo Araujo Romero, Arismar Cerqueira Sodre Junior
Summary: Efficient optical-wireless architecture for 5G networks was proposed with various front-haul configurations analyzed for network operator deployment. Visible light communication was investigated as a future access network technology. Experimental results demonstrated the coexistence of 4G and 5G networks with Gbit/s throughput in accordance with 5G NR Release 15.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Electrical & Electronic
Dinka Milovancev, Nemanja Vokic, David Loschenbrand, Thomas Zemen, Bernhard Schrenk
Summary: The study presents a mobile fronthaul methodology for analogue optical transmission of native radio signals with integrated photonic true-time delay for beam steering of phased-array antennas. Using laser-based coherent homodyne detectors and delay dissemination through ultra-dense wavelength division multiplexing ensures low complexity at the optical layer. Experimental results verify successful native radio signal transmission over a 14.3-km coherent optical fronthaul with low end-to-end error vector magnitude.
IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
(2021)
Article
Optics
Wuying Wang, Yangyu Fan, Xichun Liu, Zhe Guo, Guo Liu, Longchao Wei, Guoyun Lv
Summary: This study presents and demonstrates an approach to generating frequency-tunable biphase and quadriphase coded pulse signals using a polarization division multiplexing dualparallel Mach-Zehnder modulator (PDM-DPMZM). The proposed method allows for easy control and switching of different coding waveforms using vector modulation and phase coding techniques. Experimental results show that the phase coded pulse signals perform well at different carrier frequencies.
Article
Engineering, Electrical & Electronic
Claudio Paoloni
Summary: In order for the future 5G and 6G technologies to be successful, a ubiquitous data source is needed to increase the area capacity of the wireless distribution layer.
IEEE COMMUNICATIONS MAGAZINE
(2021)
Article
Engineering, Electrical & Electronic
Pham Tien Dat, Yuya Yamaguchi, Masayuki Motoya, Satoshi Oikawa, Junichiro Ichikawa, Atsushi Kanno, Naokatsu Yamamoto, Tetsuya Kawanishi
Summary: This study demonstrates the first fiber-millimeter-wave-fiber system in the 100-GHz band using a low-loss optical modulator and direct photonic down-conversion technology. The proposed system enables high-capacity, low-latency, and low-power consumption fiber-wireless transmission.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Optics
Xinjie Han, Haocheng Ke, Huashun Wen, Wenchan Dong, Yunru Fan, Guangwei Deng, Qiang Zhou, Heng Zhou, Kun Qiu, Jing Xu, Yong Geng
Summary: All-optical phase regeneration aims to compensate for phase distortions in coherently encoded data signals caused by imperfections and impairments during transmission. This study demonstrates a new architecture using integrated photonic devices to implement all-optical phase regeneration, achieving the best SNR improvement of over 6 dB for 40 Gbps QPSK data. The results suggest a promising avenue for practical implementation of all-optical phase regeneration in long-distance fiber transmission networks.
Article
Computer Science, Information Systems
Riqza Yasmin Khattak, Qasim Ahmed, Sultan Shoaib, Maryam Hafeez
Summary: This manuscript presents a design of a low-profile and printed array antenna for wireless access points and futuristic healthcare devices. The design is optimized using an empirical approach to achieve enhanced bandwidth, gain and efficiency performances. The antenna is printed on Rogers RT-5880 laminate, and it covers a wide bandwidth and shows good gain and efficiency.
Review
Chemistry, Multidisciplinary
Isiaka A. Alimi, Romil K. Patel, Nelson J. Muga, Armando N. Pinto, Antonio L. Teixeira, Paulo P. Monteiro
Summary: This paper discusses the potential enhancement of FWA performance with the development of 5G and beyond mobile networks, while also highlighting the challenges that may be faced in the implementation process regarding the transport network. It provides a comprehensive tutorial on the enabling technologies, design considerations, requirements, and prospects of broadband schemes, along with a review of technical challenges and potential solutions for FWA.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Electrical & Electronic
William L. Beardell, Conor J. Ryan, Garrett J. Schneider, Janusz Murakowski, Dennis W. Prather
Summary: In this paper, a new architecture is proposed for determining the locations of RF sources in three-dimensional space on a millisecond time scale. This is achieved by up-converting the RF field to an optical carrier, passing it through an array of optical fibers, and performing an analog Fourier transform using a free-space optical processor. The proposed method utilizes multiple temporal dispersion projections implemented through varied-length optical fiber segments, and can be implemented using commercial computing hardware and a CCD camera for detection.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Quang-Huy Tran, Tho-Minh Duong, Sungoh Kwon
Summary: This paper proposes a graph-based load balancing algorithm for small-cell integrated access and backhaul (IAB) networks. The algorithm estimates and adapts to network load status to tackle the unbalanced load problem. The simulation results show that the proposed algorithm distributes the load more evenly, increasing network throughput and UE satisfaction.
Article
Optics
Pham Tien Dat, Atsushi Kanno, Norihiko Sekine, Kouichi Akahane
Summary: This Letter presents a method for transmitting fifth-generation new radio (5G NR) millimeter-wave signals over a seamless fiber-terahertz-wave mobile fronthaul system in the 350 GHz band. The system utilizes a simple optical heterodyne method at the transmitter and direct detection at the receiver. As a proof-of-concept demonstration, the authors successfully transmitted 256 and 64-quadrature amplitude modulation 5G-NR-compliant signals at 24.2 and 38 GHz over the proposed system. This system can provide a simple solution for deploying ultra-dense small cells in high-frequency bands in 5G networks and beyond.
Article
Engineering, Electrical & Electronic
Majid Arezoomand, Abdolkarim Afroozeh, Siamak Pilban Jahromi, Hongxia Zhang
Summary: This paper investigates the problem of perfect quantum state transfer (PST) on the generalized honeycomb nanotorus. It characterizes the periodicity of all generalized honeycomb nanotorus and also studies the existence of PST between distinct atoms.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Samuel O. Edeagu, Rizwan A. Butt, Sevia M. Idrus, Nathan J. Gomes
Summary: This paper proposes a hybrid dynamic bandwidth allocation (DBA) scheme for converged fronthaul networks in 5G, which require low latency and high capacity. Different deployment scenarios and operating conditions in a 10-Gigabit-capable PON (XGS-PON) system are investigated using the OMNeT++ network simulator. The performance of the proposed hybrid DBA is evaluated in terms of average upstream delay and percentage of frame loss meeting a 140 μs queuing delay requirement for fronthaul traffic. Simulation results show that the proposed hybrid DBA achieves zero-frame loss for fronthaul traffic in all scenarios, highlighting its advantages over the status reporting DBA.
OPTICAL FIBER TECHNOLOGY
(2023)
Correction
Engineering, Electrical & Electronic
Alabbas A. Al-Azzawi, Aya A. Almukhtar, P. H. Reddy, S. Das, A. Dhar, M. C. Paul, H. Arof, H. Ahmad, S. W. Harun
OPTICAL FIBER TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Harith Ahmad, Maryam Jasmine Mohd Makhfuz, Norazriena Yusoff, Azim Danial Azam, Muhamad Zharif Samion
Summary: This study presents a method for synthesizing Ti2C using different etching methods, namely hydrofluoric acid (HF) and in situ generated HF using hydrochloric acid (HCl) and lithium fluoride (LiF) salt. The synthesized MXenes were characterized using various analysis methods, and their nonlinear optical properties were analyzed. The results show that the synthesized Ti2C-HF and Ti2C-HCl have 2D multilayered nanostructures with thicknesses ranging from 10 nm to 20 nm, and they exhibit potential as saturable absorbers in pulsed laser generation for future photonics applications.
Article
Optics
N. H. Muhamad Apandi, H. Ahmad, M. Q. Lokman, S. N. F. Zuikafly, H. Yahaya, M. H. Ibrahim, R. M. Rosnan, F. Ahmad
Summary: This study explores the generation of soliton and bound-state soliton passively mode-locked EDFLs using gamma ray irradiated SWCNT-PEO film as a saturable absorber. The results show that irradiated films can produce a wider range of mode-locked pulses.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Physics, Multidisciplinary
H. Ahmad, B. Nizamani, S. Sekar, M. Z. Samion, N. Yusoff, S. Venkataprasad Bhat
Summary: In this work, 2D boron carbon oxynitride (BCNO) was experimentally demonstrated as a potential mode-locker in erbium-doped fiber lasers (EDFL) and thulium-doped fiber lasers (TDFL) for the first time. The BCNO-coated arc-shaped fiber achieved mode-locking in EDFL with a pulse width of 1.56 ps, repetition rate of 19.14 MHz, and center wavelength of 1562.2 nm. In TDFL, mode-locked pulses with a duration of 1.456 ps, repetition rate of 13 MHz, and signal-to-noise ratio (SNR) of 70.3 dB were achieved by incorporating BCNO-coated arc-shaped fiber. These results highlight the potential of BCNO as a low-cost 2D material for laser-related applications.
Article
Engineering, Electrical & Electronic
M. S. M. Sa'ad, H. Ahmad, M. A. Alias, M. K. A. Zaini, K. S. Lim, S. W. Harun, K. T. V. Grattan, B. M. A. Rahman, G. Brambilla, S. A. Reduan, L. Bayang, M. F. Ismail
Summary: This article introduces a surface-mounted tilt sensor that is designed to measure the inclination angle of engineered structures or slopes in two directions. The sensor utilizes strain-sensitive fiber Bragg gratings (FBGs) for tilt angle measurement bidirectionally and uses a strain-free FBG for temperature compensation. The compact, robust, and easy-to-install tilt sensor shows excellent potential for various geotechnical applications, mainly in landslide detections, ground movement, and engineered slope monitoring, as supported by laboratory calibration and field test data.
IEEE SENSORS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Jing Wen Chew, Kok Bin Ng, Soon Xin Gan, Lian Seng Tey, Wu Yi Chong, Yuen Kiat Yap, Harith Ahmad
Summary: The performance of a Q-switched erbium doped fiber laser using a monolayer molybdenum disulfide (MoS2)-coated planarized optical waveguide was studied in this work. The MoS2-coated waveguide showed advantages in terms of a high damage threshold and a controllable interaction length with the light. The laser had a widely tunable wavelength range of 38.6 nm with a MoS2 coating length of 7.2 mm, which reduced to 5.9 nm when the interaction length was reduced to 2.5 mm. This reduction was attributed to a decrease in the number of vacancy states of MoS2 in shorter coatings. These results contribute valuable information for the development of all-planar waveguide pulsed laser sources.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
H. Ahmad, B. Nizamani, M. Z. Samion, M. Yasin
Summary: The nonlinear optical behavior of a novel zinc phosphate-based saturable absorber (SA) was investigated. Zinc phosphate was synthesized and coated on an arc-shaped fiber as SA. The linear and nonlinear optical absorption characteristics of the zinc phosphate SA were studied. The SA was incorporated into a praseodymium-doped fluoride fiber laser (PDFFL) and an erbium-doped fiber laser (EDFL) to generate stretched pulse mode-locked pulses at 1.3μm and soliton mode-locked EDFL pulses at 1561 nm, respectively, demonstrating the wideband saturable absorption capability of zinc phosphate.
OPTICAL FIBER TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Harith Ahmad, Kirubhashni Loganathan, Norazriena Yusoff, Muhamad Zharif Samion
Summary: In this study, different morphologies of zinc oxide (ZnO) were synthesized to investigate the effect of morphology on nonlinear optical properties. The impact of this effect on the performance of a mode-locked pulsed fiber laser was also examined. ZnO particle-like and flake-like samples were prepared using sol-gel and hydrothermal methods, and their nonlinear optical properties were analyzed using a twin detection technique. The results showed that the ZnO flake-like sample exhibited superior modulation depth, saturation intensity, and non-saturable loss compared to the ZnO particle-like sample. Consequently, a 1.9 mu m mode-locked pulsed fiber laser utilizing the ZnO flake-like based saturable absorber (SA) demonstrated better performance in terms of pulse width, signal-to-noise ratio (SNR), pulse energy, and efficiency. The findings of this study provide valuable guidance for selecting appropriate nanomaterial-based SAs for various photonics applications.
Article
Instruments & Instrumentation
H. Ahmad, J. W. Chiam, M. Z. Samion, N. Yusoff, M. Z. Zulkifli
Summary: This study reports on the fabrication of a saturable absorber using manganese violet (MV) and its successful application in generating mode-locked pulses in a thulium/holmium-doped fiber laser. The generated pulses have a center wavelength of 1908.9 nm, a repetition rate of 12.27 MHz, and a pulse width of 1.27 ps. This work demonstrates the potential of MV as a saturable absorber for mode-locked laser operations in the 2 μm region.
INFRARED PHYSICS & TECHNOLOGY
(2023)
Article
Optics
Harith Ahmad, Muhammad Firdaus Salleh, Muhammad Khairol Annuar Zaini, Muhamad Zharif Samion, Muhammad Faizal Ismail, Siti Aisyah Reduan
Summary: This study investigates the use of tapered fiber with different waist diameters to generate four-wave mixing effects. The results show that the conversion efficiency and stability of four-wave mixing vary with different waist diameters. Additionally, a high nonlinearity at the air-cladding region is observed when the waist diameter of the tapered fiber is reduced.
Article
Engineering, Electrical & Electronic
Muhammad Syamil Mohd Sa'ad, Harith Ahmad, Muhamad Zharif Samion, Mohamad Ashraff Alias, Muhammad Khairol Annuar Zaini, Lim Kok Sing, Kenneth T. V. Grattan, B. M. Azizur Rahman, Gilberto Brambilla, Sulaiman Wadi Harun, Mohammad Faizal Ismail
Summary: A fiber Bragg grating-based inclinometer probe with enhanced sensitivity has been developed for slope or ground movement monitoring. The probe is fabricated using a 3D printer and has a similar size to the conventional probe, with better resolution and sensitivity.
SENSORS AND ACTUATORS A-PHYSICAL
(2023)
Article
Engineering, Electrical & Electronic
H. Ahmad, B. Nizamani, M. Z. Samion, M. Z. Zulkifli
Summary: In this work, the generation of multi- and dual-wavelength fiber lasers at the S-band was demonstrated using an all-fiber-based Lyot filter in a thulium-doped fluoride fiber laser. The multiwavelength fiber laser exhibited high optical signal-to-noise ratio and stability, while the dual-wavelength fiber laser was achieved by incorporating a tunable bandpass filter in the laser cavity.
IEEE JOURNAL OF QUANTUM ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
H. Ahmad, N. A. Roslan, M. K. A. Zaini, M. Z. Samion, S. A. Reduan, Y. Wang, S. Wang, J. K. Sahu, M. Yasin
Summary: A stable multiwavelength fiber laser using bismuth-doped fiber and all-fiber Lyot filter has been proposed and demonstrated. The laser can generate up to 21 output channels within a specific wavelength range and exhibits good stability and high signal-to-noise ratio.
OPTICAL FIBER TECHNOLOGY
(2023)
