Article
Engineering, Electrical & Electronic
Mengfan Fu, Qiaoya Liu, Yicheng Xu, Hexun Jiang, Xiaobo Zeng, Yiwen Wu, Lilin Yi, Weisheng Hu, Qunbi Zhuge
Summary: This paper proposes a multi-dimensional distribution matching (MDDM) method based on bit-level shaping for implementing probabilistic shaping (PS) in high order modulation formats. The MDDM is optimized across multiple dimensions to achieve better performance and reduce implementation complexity. A degenerate MDDM method with similar performance to MDDM is also introduced. Experimental results show that the proposed methods outperform the conventional distribution matching method.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Bin Chen, Wei Ling, Yunus Can Gultekin, Yi Lei, Chigo Okonkwo, Alex Alvarado
Summary: Signal shaping is crucial in approaching Shannon's capacity but challenging at very high speeds. This letter proposes a 4D amplitude coding (4D-AC) geometric shaper architecture that can generate geometrically shaped 4D formats in real time through simple logic circuit operations. Numerical results show low losses compared to baseline formats.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Erik Borjeson, Per Larsson-Edefors
Summary: The text introduces the circuit implementations of one- and two-stage carrier phase recovery (CPR) for 256QAM coherent optical receivers, discussing the optimization of algorithms and trade-offs between energy per bit and SNR penalty. It shows that achieving energy dissipation around 1 pJ/bit at an SNR penalty of 0.6 dB is possible with specific implementations, with PCPE+BPS being the preferred choice due to its smaller area.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Hami Rabbani, Hamid Hosseinianfar, Hamed Rabbani, Maite Brandt-Pearce
Summary: This paper introduces a nonlinear model for multi-channel WDM systems, valid for arbitrary modulation formats, including asymmetric ones. The model focuses on the XPM nonlinear term to reduce nonlinear interference undergone by these formats.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Feng Tian, Tianze Wu, Yiqing Ji, Chuxuan Wang, Qi Zhang, Ran Gao, Zhipei Li, Qinghua Tian, Xiangjun Xin
Summary: A new 4D-PS ultra-high order modulation format and PA-CPR algorithm are proposed to improve GMI performance. The feasibility of the scheme is demonstrated through simulations. The results show that the proposed 8APSK-PA-CPR algorithm outperforms QPSK-PA-CPR algorithm, with lower complexity and higher coding gain.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Optics
Zhaobang Zeng, Lemeng Leng, Peiyan Zhao, Chenbin Zhang, Ding Ding, Dun Mao, Tingyi Gu, Wei Jiang
Summary: In a parallel-coupled dual-racetrack modulator, interference between resonant light in two resonators is utilized to achieve high extinction ratios for high-speed modulation. The modulator also enables the generation of four-level pulse-amplitude modulation without an external DAC.
Article
Optics
Li Zhao, Sicong Xu, Mingxu Wang, Bohan Sang, Jianyu Long, Long Zhang, Wen Zhou, Kaihui Wang, Jianjun Yu
Summary: This study proposes a probabilistic shaping delta-sigma modulation technique that improves the anti-noise capability of the modulation signal. It demonstrates that the PS-based 131072QAM signal modulated by delta-sigma modulation performs better in terms of bit error rate than the ordinary 65536QAM signal using the delta-sigma modulation scheme. The study also shows that the PS-based modulation has a lower bit error rate than soft decision-forward error correction (4 x 10(-2)).
Article
Materials Science, Multidisciplinary
Joyce Yew Pei Ling, Zaiton Abdul Mutalip, Afif Hakim Hasanudin, Faezah Jasman, Zeina Rihawi
Summary: In the field of visible light communication (VLC) systems, carrier-less amplitude and phase modulation, specifically the CAP-4 scheme, has been found to have better performance compared to basic On-Off Keying. This study analyzes the performance of CAP-2, CAP-4, and CAP-8 based on bit-error-rate, constellation diagram, and eye diagram. CAP-4 has the lowest EVM (-10.90 dB) and highest MER (11.30 dB), indicating superior performance.
OPTOELECTRONICS AND ADVANCED MATERIALS-RAPID COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Guangyi Li, Difei Shi, Xiangyan Meng, Lu Wang, Ming Li, Ninghua Zhu, Wei Li
Summary: A photonic method utilizing a dual-polarization dual-parallel Mach-Zehnder Modulator (DP-DPMZM) is proposed and experimentally verified to generate dual-band microwave waveforms with simultaneous and different formats. The DP-DPMZM consists of four sub-MZMs driven by two independent RF signals and two independent baseband signals. After photo-detection, the two baseband signals are up-converted into two different higher frequency bands. This method allows for independent tunability of the central frequencies and modulation formats of waveforms at two frequency bands, enabling diverse applications in radar and communication systems.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Haleema Khalil, Farhan Qamar, Romana Shahzadi, Asim Shahzad, Mudassar Ali, Nouman Qamar, Sattam Al-Otaibi
Summary: Radio over fiber (RoF) is an effective communication technique that combines optical fiber and free space radio paths, with important applications for futuristic networks. The performance of RoF system can be visualized by modulating data with RF signal at the same frequency at transmitter and receiver ends, and various simulations and parameter tests directly affect system performance.
Article
Chemistry, Multidisciplinary
Qiangguo Zhou, Qinxi Qiu, Tuntan Wu, Yongzhen Li, Zhiming Huang
Summary: This article proposes a novel ultrawideband terahertz linear polarization converter, which has the characteristics of high-purity output and near-zero copolarization transmission in the full band. The physical mechanism of polarization conversion is elucidated through the analysis of surface current and electric field distribution. In addition, the influence of geometric parameters on the device is discussed, providing theoretical support for the design of high-performance polarization converters.
Article
Computer Science, Information Systems
Andrew Burton, Petr Chvojka, Paul Anthony Haigh, Zabih Ghassemlooy, Stanislav Zvanovec
Summary: This paper introduces a wavelength-division multiplexing visible light communication system based on a defocused non-imaging MIMO, which utilizes the natural diversity of LEDs to generate an H-matrix without the need for optical bandpass filters. By transmitting independent sets of on-and-off keying signals on different wavelengths, the received superposed symbols can be demultiplexed. The system is empirically verified for K = 3 using red, green, and blue LEDs with varying Q-factors.
Article
Computer Science, Information Systems
Hyun-Sam Jung
Summary: The interleaved PWM can enhance the equivalent switching frequency and output current harmonics in parallel operation of three-phase converters. However, it may lead to circulating current, for which a coupled inductor is employed for suppression. A new PWM strategy has been devised to improve harmonics by modifying the interleaved carrier, although unintended additional device switching may occur.
Article
Engineering, Electrical & Electronic
Huaiyin Wang, Xingwen Yi, Jing Zhang, Fan Li
Summary: This paper investigates the impact of equalization-enhanced phase noise (EEPN) on coherent optical receivers, specifically for high-order modulation formats. The study explores the differences between intra-symbol and inter-symbol EEPN, as well as the distribution of EEPN on different modulations. Practical carrier phase recovery algorithms are also analyzed and predicted.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Jiang Chen, Jianyang Shi, Junhui Hu, Chao Shen, Nan Chi
Summary: This paper introduces carrierless amplitude and phase (CAP) as a high spectral efficiency modulation scheme in visible light communication (VLC) systems. The possibility of designing perfect DC-balanced PSFs is discussed, and the performance of odd-dimensional and even-dimensional PSFs is compared through simulations and experiments.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Optics
Zahra Nazari Chaleshtori, Stanislav Zvanovec, Zabih Ghassemlooy, Mohammad-Ali Khalighi
Summary: With the increasing use of organic light emitting diodes in various devices, visible light-based device-to-device communication is gaining importance. Researchers propose using smart phones' display pixels and built-in cameras for such communication and investigate the impact of receiver orientation and user mobility on link performance.
Article
Engineering, Electrical & Electronic
J. Bohata, D-N Nguyen, J. Spacil, D. Suslov, D. Dousek, S. Zvanovec, Z. Ghassemlooy, M. Komanec
Summary: This letter presents the results of an experimental measurement campaign using combined radio over fiber and radio over FSO technology in a cloud-based 5G fronthaul network. The results show excellent performance in terms of phase noise and signal-to-noise ratio, and also investigate the impact of atmospheric conditions on received mmW signals in the FSO channel.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2022)
Article
Computer Science, Hardware & Architecture
Zun Htay, Carlos Guerra-Yanez, Zabih Ghassemlooy, Stanislav Zvanovec, Mojtaba Mansour Abadi, Andrew Burton
Summary: This paper demonstrates the experimental implementation of a gigabit Ethernet free space optical (FSO) communications link with adaptive switching using GNU Radio and analyzes its performance. The proposed switching mechanism improves the link performance under different fog conditions and is compared with a single FSO link.
JOURNAL OF OPTICAL COMMUNICATIONS AND NETWORKING
(2022)
Article
Engineering, Electrical & Electronic
Pranav Sharda, Manav R. Bhatnagar, Zabih Ghassemlooy
Summary: In this research, a novel vehicle-to-vehicle visible light communications (VLC) system model is proposed, taking into account the impact of shadowing on VLC link performance. The performance of the system is analyzed using the diversity-multiplexing tradeoff (DMT) metric, which provides optimal tradeoff points for system design. The study also investigates the system performance under practical transmission scenarios and atmospheric turbulence conditions, revealing useful insights not previously identified in the literature.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2022)
Article
Optics
Tianming Huang, Bangjiang Lin, Zabih Ghassemlooy, Ningcong Jiang, Qiwei Lai
Summary: This paper proposes a NLOS visible light positioning system using a binocular camera and a single LED, which achieves 3D positioning of arbitrary postures and overcomes the challenges of LOS transmission path shadowing/blocking and limited field of view. The authors also propose a label-based enhanced VLP scheme, which significantly improves the system performance.
Article
Engineering, Electrical & Electronic
Jan Bohata, Dong-Nhat Nguyen, Pham Tien Dat, Zabih Ghassemlooy, Beatriz Ortega, Stanislav Zvanovec
Summary: This letter presents a method for data transmission and coverage extension in an indoor environment using the radio-over-fiber (RoF) technology and a 26 GHz millimeter-wave (mmW) radio signal. The proposed system consists of two RoF seamless wireless links to emulate a mobile fronthaul and overcome the higher attenuation of the mmW signal. Experimental evaluation shows the possibility of signal transmission over up to 20 km of optical fiber with minimal error vector magnitude for 64-QAM.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Jiandong Liu, Liang Chu, Bin Liu, Juan Liu, Yingying Hu, Xing-Dao He, Jinhui Yuan, Yangbo Zhou, Dejun Liu, Zabih Ghassemlooy, James Martin, Yong Qing Fu, Qiang Wu
Summary: This study proposes and experimentally demonstrates a highly sensitive hydrogen sensor coated with Pt/WO3 powder and erbium-doped fiber amplifier (EDFA). The sensor is constructed by splicing a tapered small-diameter coreless fiber (TSDCF) between two single-mode fibers (SMFs). The Pt/WO3 powder on the surface of a polydimethylsiloxane (PDMS) film coated on the TSDCF structure serves as the hydrogen-sensitive material. An EDFA is introduced to improve the Q factor and resolution of the sensor's output spectrum. The sensor exhibits good stability with a light intensity fluctuation of less than 1.26 dB over a 30-minute duration, and a maximum light intensity variation and sensitivity of -32.41 dB and -21.25 dB/%, respectively, when the hydrogen concentration varies from 0% to 1.44%.
IEEE SENSORS JOURNAL
(2023)
Article
Optics
Carlos Guerra-Yanez, Victor Guerra, Cristo Jurado-Verdu, Jose Rabadan, Rafael Perez-Jimenez, Zabih Ghassemlooy, Stanislav Zvanovec
Summary: This work explores the use of symmetries in radiant surfaces to calculate induced irradiance distributions. A general mathematical expression is developed and applied to different types of sources. Experimental evaluation and comparisons are conducted, showing significant improvements in computation time and accuracy. The proposed approach enhances short-range predictions for extended sources. The article also outlines applications in optical wireless communications.
Article
Engineering, Electrical & Electronic
Hongxu Wang, Huixin Zhang, Zabih Ghassemlooy, Tian Zhang
Summary: In this paper, a low-complexity and high-performance clipping-free multilayer optical orthogonal frequency division multiplexing (OFDM) scheme is proposed for optical wireless communication (OWC). The scheme arranges the symbols of multi-layer quadrature amplitude modulation (QAM) in the frequency domain to generate a bipolar time-domain signal using inverse fast Fourier transform (IFFT) at the transmitter. At the receiver, a zero-value regression (Re0) -based demodulation is proposed for optimizing the bit error rate (BER). The proposed scheme achieves similar system complexity as single-layer modulations and offers improved power efficiency and avoidance of interlayer interference.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2023)
Article
Computer Science, Hardware & Architecture
Waseem Ozan, Izzat Darwazeh, Kyle Jamieson
Summary: This paper introduces a new design called Partial Symbol Recovery (PSR) to address packet collisions in wireless networks. By bootstrapping a decoder from the interference-free parts of data symbols, PSR improves performance and consistently enhances throughput for different data types and modulation methods.
IEEE-ACM TRANSACTIONS ON NETWORKING
(2023)
Article
Computer Science, Information Systems
Tianming Huang, Bangjiang Lin, Zabih Ghassemlooy, Ningcong Jiang, Qiwei Lai
Summary: This article introduces a 3-D non-line-of-sight (NLOS) VLP system that uses a single LED and an image sensor (IS) to address the problem of obstructed LOS paths. The system utilizes an optical camera communication (OCC) subsystem to receive the transmitter's position based on NLOS links. The proposed system achieves a 90th percentile accuracy of < 22 cm for 3-D positioning and is the first to demonstrate 3-D NLOS VLP using just a single LED and an IS.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Article
Optics
Xiangyu Wan, Bangjiang Lin, Zabih Ghassemlooy, Tianming Huang, Jiabin Luo, Yongqi Ding
Summary: Non-line-of-sight (NLOS) optical camera communications (OCC) provide better link availability and mobility compared to line-of-sight links. This study proposes an NLOS OCC system that maps data signals into color pulse width modulation (CPWM) symbols and uses a convolutional neural network for demodulation, effectively reducing intersymbol interference.
Article
Engineering, Electrical & Electronic
Vaigai Nayaki Yokar, Hoa Le-Minh, Zabih Ghassemlooy, Wai Lok Woo
Summary: In this study, the authors experimentally demonstrate the ability of the smartphone-to-smartphone-based visible light communications (S2SVLC) system to support high-quality multimedia transmissions. They investigate the mean square error estimation, peak signal-to-noise degradation, bit error rate, and data rate achieved under different conditions. The results show that the system's performance is significantly impacted by data transmission at different conditions.
IET OPTOELECTRONICS
(2023)
Article
Computer Science, Information Systems
Shivani Rajendra Teli, Carlos Guerra-Yanez, Vicente Matus Icaza, Rafael Perez-Jimenez, Zabih Ghassemlooy, Stanislav Zvanovec
Summary: This paper introduces a concept of a multilevel bipolar on-off keying hybrid optical wireless communication system for indoor IoT applications. The system utilizes a single LED as a transmitter and photodiode and camera-based receivers. Experimental results show that the proposed hybrid system improves the data rate and error rate of VLC and OCC links, respectively, by doubling the bandwidth. The scheme provides independent link performance regardless of the differences between the operating R-b of VLC and OCC over a range of transmission spans.
Article
Engineering, Electrical & Electronic
Tongyang Xu, Fan Liu, Christos Masouros, Izzat Darwazeh
Summary: The integration of sensing and communication functionalities has gained significant research interest as a hardware-, power-, spectrum-, and cost-efficient solution. A dual-functional sensing and communication framework is implemented in this experimental work, where a single radiation waveform can realize both functions. The experimental results show that the dual-functional approach can achieve comparable BER performance with pure communication-based solutions while achieving fine sensing beampatterns and realistic sensing functionality simultaneously.
IEEE OPEN JOURNAL OF THE COMMUNICATIONS SOCIETY
(2022)
