Article
Engineering, Electrical & Electronic
Nizar Bouhlel, Majed Saad, Faouzi Bader
Summary: This paper addresses a MIMO communication system based on GSM and DP antennas in sub-THz bands, aiming to improve SE while reducing spatial correlation effects. The proposed ML and MOB-MMSE detectors jointly detect complex symbols and virtual bits conveyed by activated polarization and transmit antenna combination index. The DP-GSM system is studied over correlated fading channels, showing robustness to spatial correlation effects under Rician fading. Additionally, an ABEP upper bound is derived and analyzed for DP-GSM system over correlated fading channels, considering sub-THz impairments and comparing with DP-SMX and UP-GSM systems. DP-GSM with low order modulation outperforms UP-GSM and provides cost reduction by using a lower number of RF chains in transmitter architecture based on RF-switching.
IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
(2021)
Article
Engineering, Electrical & Electronic
Jinxiang Song, Christian Haeger, Jochen Schroeder, Alexandre Graell Amat, Henk Wymeersch
Summary: We propose an autoencoder-based transceiver for a wavelength division multiplexing system impaired by hardware imperfections. The autoencoder is designed following the architecture of conventional communication systems, enabling it to have similar performance and improve training convergence rate. Simulation results show that the proposed autoencoder significantly outperforms the conventional approach in terms of spectral efficiency.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2022)
Article
Automation & Control Systems
Rong-Heng Cui, Xue-Jun Xie
Summary: This paper focuses on the problem of output feedback stabilization of stochastic planar nonlinear systems with output constraint. By introducing new nonlinear mappings, adding a power integrator and homogeneous domination techniques, two new design and analysis frameworks are established in this paper to achieve stochastic asymptotic stability and stochastic finite-time stability of the trivial solution of the closed-loop system, while ensuring the requirements of almost sure boundedness of the closed-loop signals and the symmetric output constraint.
Article
Multidisciplinary Sciences
Wei Hu
Summary: Novel stochastic finite-time stability criteria for stochastic nonlinear systems with stochastic impulse effects are established in this paper. The significance and usefulness of the results are demonstrated through an example.
Article
Automation & Control Systems
Haiqi Peng, Quanxin Zhu
Summary: This article focuses on the stochastic finite time stability (SFTS) and stochastic fixed time stability (SFIXTS) of switched stochastic nonlinear functional systems. It establishes several novel theorems on SFTS and SFIXTS using the Lyapunov-Razumikhin approach, stochastic analysis techniques, and stochastic process theory. The article also provides estimations of stochastic settling time, considering the effects of noise, time-delays, and switches.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2023)
Article
Automation & Control Systems
Wuquan Li, Miroslav Krstic
Summary: The study presents mean-nonovershooting tracking control designs for stochastic strict-feedback nonlinear systems, with a focus on achieving strict mean-nonovershooting tracking. By designing a new controller, arbitrary reference trajectories can be tracked from below, while maintaining the mean-square boundedness of the system states. The control gains are independent of the initial conditions of system states and derivatives of the reference trajectory, providing a better feature compared to existing research results.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2021)
Article
Mathematics, Applied
Mengling Li, Zhengyong Ouyang, Feiqi Deng, Ze-Hao Wu
Summary: This paper focuses on the stochastic dissipativity theory and applications for nonlinear stochastic systems with Markov jump and Levy noise. The theory is established based on the dissipation inequality, multi supply rates, multi storage functions and stochastic analysis tools, and utilized to obtain sufficient conditions for system stability. The effectiveness of the results is validated through examples.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2021)
Article
Engineering, Electrical & Electronic
Filipe M. Ferreira, Eric Sillekens, Boris Karanov, Robert Killey
Summary: An advanced digital backward-propagation (DBP) method using a separate-channels approach (SCA) is investigated for the compensation of inter-channel nonlinearities in spatial- and wavelength-multiplexed systems. Results show that SCA-DBP can relax step size requirements and improve performance, while transmission performance can be enhanced by sub-band processing of back propagated channels in spatial multiplexed systems.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Multidisciplinary Sciences
K. Murali, S. Rajasekar, Manaoj V. Aravind, Vivek Kohar, W. L. Ditto, Sudeshna Sinha
Summary: Logical Stochastic Resonance (LSR) produces a logic function response in moderate noise, extendable to higher-level logic architecture. Furthermore, Logical Vibrational Resonance (LVR) and Logical Coherence Resonance (LCR) exhibit similar effects as LSR.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2021)
Article
Automation & Control Systems
Kun-Zhi Liu, Andrew R. Teel, Xi-Ming Sun
Summary: This paper addresses the event-triggered control problem for stochastic nonlinear systems in the presence of stochastic transmission protocols. A stochastic event-triggered transmission strategy is proposed and a new Lyapunov function is constructed to analyze the stability of the resulting system. Stability conditions and explicit parameter design are derived, and examples are provided to illustrate the effectiveness.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Engineering, Electrical & Electronic
Hyeongtaek Lee, Hyuckjin Choi, Hwanjin Kim, Sucheol Kim, Chulhee Jang, Yongyun Choi, Junil Choi
Summary: Research on massive MIMO systems often use time division duplexing for the base station to acquire channel state information, while still needing to transmit downlink training signals to support spatial multiplexing due to the mismatch between transmit and receive antennas at user equipment. After receiving downlink signals, the UE must use pre-defined codebook to send quantized CSI feedback to the BS.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2021)
Article
Computer Science, Information Systems
Tianliang Zhang, Shengyuan Xu, Weihai Zhang
Summary: A control scheme for stochastic predefined-time stabilization of continuous-time stochastic Ito systems is proposed in this paper. It allows the upper bound of the mean value of the settling-time function to be below an arbitrarily given positive value. Lyapunov-type results for predefined-time stabilization of general stochastic Ito systems are presented. Additionally, a state feedback control scheme is designed for a class of stochastic nonlinear systems in strict-feedback form. Two simulation examples are provided to demonstrate the usefulness of the proposed stochastic predefined-time stabilization.
SCIENCE CHINA-INFORMATION SCIENCES
(2023)
Article
Automation & Control Systems
Wuquan Li, Miroslav Krstic
Summary: In this paper, new state feedback control designs are proposed for lower/upper triangular nonlinear systems with multiplicative stochastic sensor uncertainty. For lower triangular nonlinear systems with small sensor noise, a novel control design is developed to simultaneously dominate the nonlinear functions and sensor noise with small multiplicative gain. For upper triangular nonlinear systems, a new low-gain domination design is proposed to effectively deal with sensor noise with arbitrarily large intensities. These designs ensure the closed-loop system to have an almost surely unique global solution; the origin of the closed-loop system is mean-square stable, and the states can be regulated to zero almost surely. Two simulation examples are provided to illustrate the designs.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2023)
Article
Computer Science, Artificial Intelligence
Xiyue Guo, Huaguang Zhang, Jiayue Sun, Yu Zhou
Summary: This article proposes a preassigned time adaptive tracking control problem for stochastic multiagent systems with deferred full state constraints and deferred prescribed performance. A modified nonlinear mapping is designed to eliminate the constraints on the initial value conditions and achieve deferred prescribed performance for stochastic MASs that provide only local information.
IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS
(2023)
Article
Computer Science, Information Systems
Kapseok Chang, Woncheol Cho, Byung-Jae Kwak, Young-Jo Ko
Summary: This article proposes a cell-search scheme for time-critical industrial IoT over mobile networks operating in high-frequency bands. The scheme achieves high timing accuracy and a larger set of cell IDs through the design of primary and secondary synchronization signals based on distributed concatenations. Compared to 5G NR, the proposed scheme has advantages in terms of lower timing detection complexity, a larger set of cell IDs, improved timing and cell ID detection performance, shorter cell-search time, and lower battery consumption.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Oleg Sidelnikov, Alexey Redyuk, Stylianos Sygletos, Mikhail Fedoruk, Sergei Turitsyn
Summary: The study utilizes convolutional neural networks to compensate for nonlinear signal distortions in optical communication systems, optimizing algorithmic complexity to improve learning efficiency and performance.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Review
Chemistry, Analytical
Mingming Tan, Pawel Rosa, Tu T. Nguyen, Mohammad A. Z. Al-Khateeb, Md. Asif Iqbal, Tianhua Xu, Feng Wen, Juan D. Ania-Castanon, Andrew D. Ellis
Summary: This paper reviews different designs of distributed Raman amplifiers proposed to minimize the signal power profile asymmetry in mid-link optical phase conjugation systems. The paper demonstrates how symmetrical signal power profiles can be achieved using various distributed Raman amplification techniques, both in single-span and multi-span scenarios. Additionally, the paper shows the predicted reduction in Kerr nonlinear product and performance in in-line/long-haul transmission using numerical simulations.
Article
Optics
Sonia Boscolo, Tu T. Nguyen, Abdallah A. Ali, Stylianos Sygletos, Andrew D. Ellis
Summary: The study proposes a kernel-based adaptive filtering method to suppress phase noise in dual-pump fibre-based optical phase conjugation. Experimental and numerical demonstrations show improved signal-to-noise ratio over conventional PN compensation, with no penalty in performance across a range of pump-phase mismatch values. The method is applicable to 64-QAM modulation and its performance is evaluated through numerical simulations in a transmission setup with mid-link OPC.
Article
Optics
Yiming Li, Zhouyi Hu, David M. Benton, Abdallah Ali, Mohammed Patel, Andrew D. Ellis
Summary: This paper experimentally demonstrates 10-channel mode-division multiplexed free-space optical transmission using 5 spatial modes. Strong inter-mode cross talk is observed when using a complete orthogonal mode set as independent channels. A successive interference cancellation based multiple-input multiple-output digital signal processing algorithm is applied to mitigate the inter-mode cross talk and supports unequal transmit and receive channel numbers, improving cross talk resiliency.
Article
Engineering, Electrical & Electronic
Xun Mu, Alessandro Ottino, Filipe M. Ferreira, Georgios Zervas
Summary: We propose an automated method for designing multi-core fibres, which uses neural networks to estimate coating loss and particle swarm optimization algorithm to explore optimal designs. The method achieves low crosstalk and maximizes effective mode area, and the fibres exceed the capacity of existing designs.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2022)
Article
Optics
Zhouyi Hu, Yiming Li, David M. Benton, Abdallah A. Ali, Mohammed Patel, Andrew D. Ellis
Summary: In this article, we present a method for mode multiplexing and demultiplexing in high-capacity free-space optical communications using commercial mode-selective photonic lanterns. By optimizing mode selection and applying adaptive loading, we achieve high throughput and net data rates for multiple independent channels.
Article
Optics
Xun Mu, Alessandro Ottino, Filipe M. Ferreira, Georgios Zarvas
Summary: 6-core and 8-core trench-assisted heterogeneous fibres are designed using artificial intelligence-based techniques, achieving low crosstalk and low loss. The influence of additional cores on the fiber performance is revealed through comparison analysis.
Article
Engineering, Electrical & Electronic
Zhouyi Hu, Zhaozhong Chen, Yiming Li, David M. Benton, Abdallah A. I. Ali, Mohammed Patel, Martin P. J. Lavery, Andrew D. Ellis
Summary: This paper presents the design and experimental demonstration of an adaptive multi-modal FSO transceiver to enhance robustness and high capacity in free-space optical communications under atmospheric turbulence. Modulation formats and power for different transmit modes can be adaptively allocated at the transmitter side based on dynamically estimated channel state information. At the receiver side, the most suitable multi-input/multi-output decoder can be selected to meet the forward error correction requirement with minimal power consumption. Through turbulence emulation using time-division multiplexed transmitter and receiver emulation and a spatial light modulator, an aggregate data rate of 590 Gbit/s/wavelength is achieved under strong atmospheric turbulence, validating the feasibility of the proposed adaptive transceiver over a turbulent FSO link. Moreover, all key devices, such as transponder, multiplexer, and demultiplexer, used in this work are commercially available to demonstrate practical applicability.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Yiming Li, Zhaozhong Chen, Zhouyi Hu, David M. Benton, Abdallah A. I. Ali, Mohammed Patel, Martin P. J. Lavery, Andrew D. Ellis
Summary: We experimentally demonstrate the enhanced atmospheric turbulence resiliency in a 137.8 Gbit/s/mode mode-division multiplexing free-space optical communication link through the application of a successive interference cancellation digital signal processing algorithm. The turbulence resiliency is further enhanced through redundant receive channels in the mode-division multiplexing link. The proof of concept demonstration achieves a record-high mode- and polarization-division multiplexing channel number, line rate, and net spectral efficiency in emulated turbulent links in a mode-division multiplexing free-space optical system.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Multidisciplinary
David M. Benton, Andrew D. Ellis, Yiming Li, Zhouyi Hu
Summary: Emulated atmospheric turbulence effects can be generated using a DMD micromirror array, and the resulting scintillation levels are consistent with standard turbulence models.
ENGINEERING RESEARCH EXPRESS
(2022)
Article
Optics
Vladimir Gordienko, Filipe M. Ferreira, Vitor Ribeiro, Nick Doran
Summary: We introduce a new interferometric fiber optic parametric amplifier (FOPA) that can suppress unwanted four-wave mixing products. We simulate two configurations, one rejecting idlers and the other rejecting nonlinear crosstalk from the signal output port. The simulations demonstrate that idlers can be suppressed by >28 dB across at least 10 THz, allowing the reuse of idler frequencies for signal amplification and doubling the FOPA gain bandwidth. We show that this can be achieved even with real-world couplers by introducing a small attenuation in one of the interferometer arms.
Article
Optics
Yiming Li, Zhaozhong Chen, David M. Benton, Mohammed Patel, Martin P. J. Lavery, Andrew D. Ellis
Summary: We have experimentally demonstrated high-capacity polarization-and mode-division multiplexing free-space optical transmission with strong turbulence resiliency. A compact spatial light modulator-based polarization multiplexing multi-plane light conversion module was used to emulate strong turbulent links. By employing advanced decoding techniques and redundant receive channels, the strong turbulence resiliency in a mode-division multiplexing system was significantly improved, achieving record-breaking line rates and spectral efficiencies.
Article
Engineering, Electrical & Electronic
Benedikt Geiger, Eric Sillekens, Filipe Ferreira, Robert Killey, Lidia Galdino, Polina Bayvel
Summary: The performance of a wideband coherent receiver was studied, focusing on the impact of digital pre-distortion, geometric constellation shaping, pilot sequence detection, and the number of sub-channels in the super-channel. A net data rate of 2.36 Tb/s was achieved after transmitting an 8 x 26 GBd DP-GS-256-QAM super-channel over a distance of 75 km using a single 110 GHz electrical bandwidth receiver. The overall improvement in achievable information rate due to digital pre-distortion and tailored geometric constellation shaping was 1.2 bit/4D-sym.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Optics
Zhouyi Hu, Yiming Li, Zhaozhong Chen, David M. Benton, Abdallah A. I. Ali, Mohammed Patel, Martin P. J. Lavery, Andrew D. Ellis
Summary: Free-space optical (FSO) communication has gained much interest due to its cost-efficiency and high system capacity. Combining modal-division multiplexing with conventional techniques can unlock the full potential of FSO communications. This paper reviews recent progress in multi-modal FSO communication systems and discusses practical design issues. The authors also present two demonstrations achieving record-high data rates using commercial equipment, highlighting the potential of this technique.
OPTICS COMMUNICATIONS
(2023)