Article
Computer Science, Information Systems
Huaicong Kong, Min Lin, Zining Wang, Jin-Yuan Wang, Wei-Ping Zhu, Jiangzhou Wang
Summary: This letter investigates the return link performance of a high throughput satellite system with a feeder link using free-space optical technology and a user link employing radio frequency transmission. By combining rate splitting uplink non-orthogonal multiple access with beamforming in the user link, the spectral efficiency can be improved. The study derives a closed-form average throughput expression of the system with the proposed scheme and provides simulation results to demonstrate its superiority.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Junrong Ding, Dongpeng Kang, Xiaolong Xie, Ling Wang, Hongyu Wu, Liying Tan, Jing Ma
Summary: This paper presents a performance analysis of dual-hop mixed RF/FSO systems with fixed-gain AF relaying under pointing errors. The RF link experiences kappa-mu shadowed fading, while the FSO link encounters Fisher-Snedecor F turbulence with pointing errors. Closed-form approximate expressions for end-to-end SNR statistics are derived, and the effects of system and channel parameters are analyzed. The derived approximate expressions are verified through Monte Carlo simulations.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Automation & Control Systems
Dan Ma
Summary: This article examines the delay range for robust consensus of unstable first-order agents using proportional and proportional-derivative control protocols subject to time-varying delays. The results show that the agent dynamics and the graph connectivity may limit the range of tolerable delays, and incorporating the delay variation rate in the design of the PD control protocol can expand the range of achievable robust consensus.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Computer Science, Information Systems
Li Cho, Xianhua Yu, Chau-Yun Hsu, Pin-Han Ho
Summary: This article focuses on the issue of high power consumption in the 802.11ah uplink transmitter due to high PAPR, and introduces a novel scheme called ISR for receiver-side signal compensation, which can improve PA efficiency by 4-9 dB for uplink signaling.
Article
Computer Science, Information Systems
Jihoon Choi, Jingon Joung, Bang Chul Jung
Summary: This article investigates a secure uplink multiple-input multiple-output communication system, proposes a secure multiple access method, extends the secure STLC scheme from single-antenna to two-antenna users, and achieves full spatial diversity.
IEEE SYSTEMS JOURNAL
(2021)
Article
Automation & Control Systems
Yalin Deng, Huasheng Zhang, Jianwei Xia, Wei Sun
Summary: This article investigates the exponential H-infinity tracking control problem of uncertain switched stochastic systems with mixed time-varying delays. A delay-dependent sufficient conclusion is obtained, ensuring the system stability and H-infinity tracking performance. Corresponding controllers are designed based on the stability analysis.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2022)
Article
Automation & Control Systems
Ying Zhao, Quanxin Zhu
Summary: This paper discusses the existence and boundedness of unique global solution for highly nonlinear switched stochastic systems with time delays and studies the stability conditions and control methods. By introducing a delay feedback control function and using methods like mathematical induction, the H∞ stability and pth moment exponential stability of the systems are proved. An explanatory example is provided to demonstrate the effectiveness of the main results.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2021)
Article
Automation & Control Systems
Kai Zhang, Bin Zhou, Guang-Ren Duan
Summary: This paper investigates the consensus problem of linear multi-agent systems with large input and communication delays. A novel reduced-order observer-based finite dimensional protocol is proposed to solve the problem, assuming only the relative output among agents is available and the delays are constant and exactly known. The proposed protocols are robust to changes in communication topology and allow for time-varying and unknown delays, if the systems only contain input delays. Simulation results on spacecraft formation flying system demonstrate the effectiveness of the proposed approach.
SYSTEMS & CONTROL LETTERS
(2023)
Article
Mathematics, Interdisciplinary Applications
Yeong-Hwa Chang, Cheng-Yuan Yang, Hung-Wei Lin
Summary: An adaptive fuzzy sliding-mode controller is proposed for multiple Euler-Lagrange systems communicated with directed topology. Using adaptive techniques, the control scheme achieves the objective of globally asymptotic stability.
Article
Automation & Control Systems
Lixuan Zhang, Kai Zhang, Huaiyuan Jiang
Summary: This paper investigates the consensus problem for leader-following multi-agent systems characterized by discrete-time multiple input delays linear systems with directed communication topologies. Full-order observer-based output feedback protocols are established by using the relative outputs and inputs of neighboring agents, under reasonable assumptions. To overcome the impact of potential network attacks, the relative inputs of the proposed protocols are truncated, forbidding the exchange of communication information between neighboring agents, making the closed-loop leader-following MAS immune to attacks and achieving consensus. Additionally, the improved attack-free protocols allow arbitrarily large yet bounded delays and require only relative output measurements, reducing communication burden and making them easy to implement in practice.
INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE
(2023)
Article
Engineering, Mechanical
Xiangyang Cao, Chenghui Zhang, Daduan Zhao, Yan Li
Summary: This paper investigates the guaranteed cost positive consensus for linear multi-agent systems (MASs) with multiple time-varying delays and switching topologies. The positive consensus criterion and switching signals are derived by combining multiple Lyapunov-Krasovskii functionals with mode-dependent average dwell time approaches. It realizes a trade-off between the consensus regulation performance and the control energy consumption of MASs.
NONLINEAR DYNAMICS
(2022)
Article
Computer Science, Artificial Intelligence
Yingkang Xie, Qian Ma
Summary: This article explores the adaptive event-triggered-based neural network control for switching nonlinear systems with nonstrict-feedback structure and time-varying delays. The switching observer is designed for estimating unmeasurable states, and a compensation system is introduced to deal with the existence of time-varying input delay. The study establishes the average dwell-time (ADT) scheme and the event-triggered controller to achieve the semiglobal uniform ultimate boundedness (SGUUB) of all variables and to avoid Zeno behavior. The numerical simulation demonstrates the effectiveness of the proposed control approach.
IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS
(2023)
Article
Computer Science, Information Systems
Chenglin Zhang, Wentao Shi, Zijun Gong, Qunfei Zhang, Cheng Li
Summary: Efficient target localization is crucial for marine applications in the Internet of Underwater Things (IoUT). A-optimality criterion-based observer trajectory optimization problem is formulated to improve localization performance based on time delay and Doppler shift measurements. The proposed method addresses the conflict between the nonaccessible zone constraint and observer dynamics constraint using a warning zone-based augmented Lagrange multiplier approach. Extensive simulations demonstrate the improved target localization accuracy achieved by trajectory optimization.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Article
Mathematics, Applied
Lina Fan, Yuan Lv, Quanxin Zhu
Summary: This paper addresses the globally stochastic exponential input-to-state stability (ISS) of discrete-time switched stochastic systems with partially unstable subsystems under time-varying delays and external input. It proposes a solution using mode-dependent average dwell time and multiple Lyapunov-Krasovskii functional to overcome the influences caused by the partially unstable subsystems and time-varying delays. New stability criteria are derived based on related systems, extending previous work and relaxing some restrictions. The effectiveness of the study is verified through two examples.
APPLIED MATHEMATICS AND COMPUTATION
(2023)
Article
Engineering, Electrical & Electronic
Jing Wang, Xingtao Wang
Summary: This paper addresses the H-infinity control problem for a class of uncertain switched singular systems with time-varying state delays under asynchronous switching. The exponential stability of the system is guaranteed by finding a novel Lyapunov-Krasovskii function and utilizing average dwell time technique. A condition for ensuring the H-infinity performance of the original system is derived, and strict LMI formulas for solving the state feedback controller are provided. Numerical examples are presented to demonstrate the effectiveness of the proposed methods.
CIRCUITS SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
Saheed Olanigan, Lei Cao, Ramanarayanan Viswanathan
JOURNAL OF ELECTRONIC IMAGING
(2016)
Article
Telecommunications
Amrit Kharel, Lei Cao
IEEE COMMUNICATIONS LETTERS
(2018)
Article
Engineering, Aerospace
Hadi Kasasbeh, Lei Cao, Ramanarayanan Viswanathan
IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS
(2019)
Article
Engineering, Aerospace
Rojina Adhikary, John N. Daigle, Lei Cao
IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS
(2020)
Article
Computer Science, Information Systems
Xingjian Sun, Shailee Yagnik, Ramanarayanan Viswanathan, Lei Cao
Summary: This paper investigates the performance of using the XOR rule to detect deterministic signals in bivariate Gaussian noise. The study finds that when the correlation coefficient approaches 1, the XOR rule with identical, alternating partitions of observations at the sensors (XORAP) is the optimal fusion rule. The Bayes error of XORAP decreases to zero at a slower rate compared to the exponential decrease of CLRT.
Proceedings Paper
Computer Science, Hardware & Architecture
Amrit Kharel, Lei Cao
2018 15TH IEEE ANNUAL CONSUMER COMMUNICATIONS & NETWORKING CONFERENCE (CCNC)
(2018)
Proceedings Paper
Engineering, Electrical & Electronic
Rojina Adhikary, John N. Daigle, Lei Cao
GLOBECOM 2017 - 2017 IEEE GLOBAL COMMUNICATIONS CONFERENCE
(2017)
Article
Engineering, Electrical & Electronic
R. Wesley Henderson, Paul M. Goggans, Lei Cao
DIGITAL SIGNAL PROCESSING
(2017)
Article
Computer Science, Information Systems
Natarajan Meghanathan
JOURNAL OF KING SAUD UNIVERSITY-COMPUTER AND INFORMATION SCIENCES
(2016)
Proceedings Paper
Computer Science, Hardware & Architecture
Amrit Kharel, Lei Cao
2015 WIRELESS TELECOMMUNICATIONS SYMPOSIUM (WTS)
(2015)
Proceedings Paper
Computer Science, Information Systems
R. Adhikary, J. N. Daigle
2015 IEEE 12th International Conference on Mobile Ad Hoc and Sensor Systems (MASS)
(2015)