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IEEE Symposium on Computers and Communications (ISCC)

作者： Xavier, Daniel M. Silva, Natassya B. F. Branco, Kalinka R. L. J. C. Univ Sao Paulo Escola Engn Sao Carlos Sao Carlos Brazil Univ Tecnol Fed Parana Cornejo Procopio Brazil Univ Sao Paulo Inst Ciencias Matemat & Comp Sao Carlos Brazil

ISBN: (纸本)9781728129990

Unmanned Aerial Vehicles (UAVs) are aircraft that can be autonomously operated and doesn't need a pilot aboard. Consequently, the autopilot is one of the main parts of an UAV, being responsible for stabilising the aircraft during the flight, executing navigation tasks and sensing the environment. Several path-following simulations for loiter paths are described in the literature, but most of them only consider the kinematics model of an aircraft. Therefore, this paper compares path-following algorithms for loiter paths in a more realistic scenario, using Software-in-the-Loop simulations and considering the dynamic model of the aircraft in the flight simulator X-Plane. The algorithms compared are: Carrot-Chasing, Pure Pursuit and Line-of-Sight (PLOS) and Non-Linear Guidance Law (NLGL). Lastly, a new algorithm (NLGL+) is proposed with a modification from the original algorithm and its results show smaller errors and less effort than all path-following algorithms.

关键词： Software-in-the-loop unmanned aerial vehicles navigation path-following algorithms

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An algorithmic view of ℓ2 regularization and some path-following algorithms

The Journal of Machine Learning Research

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The Journal of Machine Learning Research 2021年第1期22卷 6123-6184页

作者： Yunzhang Zhu Renxiong Liu Department of Statistics The Ohio State University Columbus OH

We establish an equivalence between the ℓ2-regularized solution path for a convex loss function, and the solution of an ordinary differentiable equation (ODE). Importantly, this equivalence reveals that the solution path can be viewed as the flow of a hybrid of gradient descent and Newton method applying to the empirical loss, which is similar to a widely used optimization technique called trust region method. This provides an interesting algorithmic view of ℓ2 regularization, and is in contrast to the conventional view that the ℓ2 regularization solution path is similar to the gradient flow of the empirical loss. New path-following algorithms based on homotopy methods and numerical ODE solvers are proposed to numerically approximate the solution path. In particular, we consider respectively Newton method and gradient descent method as the basis algorithm for the homotopy method, and establish their approximation error rates over the solution path. Importantly, our theory suggests novel schemes to choose grid points that guarantee an arbitrarily small suboptimality for the solution path. In terms of computational cost, we prove that in order to achieve an ε-suboptimality for the entire solution path, the number of Newton steps required for the Newton method is O(ε-1/2), while the number of gradient steps required for the gradient descent method is O(ε-1 ln(ε-1)). Finally, we use ℓ2-regularized logistic regression as an illustrating example to demonstrate the effectiveness of the proposed path-following algorithms.

关键词： ℓ2 regularization path-following algorithms Newton method gradient descent method convergence rate analysis

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3D path-following algorithms for Unmanned Aerial Vehicles Adjusted with Genetic Algorithm 1

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4th Workshop on Communication in Critical Embedded Systems (WoCCES)

作者： Pelizer, Guilherme, V Silva, Natassya B. F. Branco, Kalinka R. L. J. C. Univ Sao Paulo Ave Trabalhador Sao Carlense 400 BR-13566590 Sao Carlos SP Brazil

ISBN: (数字)9783319614038

ISBN: (纸本)9783319614038;9783319614021

Unmanned Aerial Vehicle (UAV) is a growing research topic due to its wide range of applications. One of its major challenges is the development of the autopilot, responsible for keeping the aircraft in desired flight conditions and for executing navigation tasks. A navigation task that is usually necessary is the path-following, which guarantees that the aircraft follows a predefined trajectory. It is possible to find several approaches for this function, based in geometric and control techniques;however, compared only for the 2D scenario. Therefore, this paper objective is to present new extended path-following algorithms for the 3D scenario, based in the well-known path-following algorithms Lookahead, Non-Linear Guidance Law (NLGL), Pure Pursuit and Line-of-Sight (PLOS) and Vector Field. The algorithms parameters are obtained with Genetic Algorithm optimisation and a comparison between all of them is performed in an environment with and without wind. The results from the simulations show that Vector Field has the best performance and PLOS has the worse one due to a high effort demanded.

关键词： path-following algorithms Genetic Algorithm Unmanned Aerial Vehicles

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Physical Layer Security Aided Wireless Interference Networks in the Presence of Strong Eavesdropper Channels

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IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY 2021年 16卷 3228-3240页

作者： Sheng, Zhichao Tuan, Hoang Duong Nasir, Ali Arshad Poor, H. Vincent Dutkiewicz, Eryk Shanghai Univ Key Lab Specialty Fiber Opt & Opt Access Networks Shanghai Inst Adv Commun & Data Sci Shanghai 200444 Peoples R China Univ Technol Sydney Sch Elect & Data Engn Sydney NSW 2007 Australia King Fahd Univ Petr & Minerals KFUPM Dept Elect Engn Dhahran 31261 Saudi Arabia Princeton Univ Dept Elect & Comp Engn Princeton NJ 08544 USA

Under both long (infinite) and short (finite) blocklength transmissions, this paper considers physical layer security for a wireless interference network of multiple transmitter-user pairs, which is overheard by multiple eavesdroppers (EVs). The EVs are assumed to have better channel conditions than the legitimate users (UEs), making the conventional transmission unsecured. The paper develops a novel time-fraction based transmission, under which the information is transmitted to the UEs within a fraction of the time slot and artificial noise (AN) is transmitted within the remaining fraction to counter the strong EVs' channels. Based on channel distribution information of UEs and EVs, the joint design of transmit beamforming, time fractions and AN power allocation to maximize the worst users' secrecy rate is formulated in terms of nonconvex problems. path-following algorithms of low complexity and rapid convergence are proposed for their solution. Simulations are provided to demonstrate the viability of the proposed methodology.

关键词： Probability Power system reliability Optimization Wireless communication Optical transmitters Fading channels Communication system security Interference network physical layer security outage-aware beamforming nonconvex optimization path-following algorithms

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Security and Energy Harvesting for MIMO-OFDM Networks

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IEEE TRANSACTIONS ON COMMUNICATIONS 2020年第4期68卷 2593-2606页

作者： Hoang, Tiep M. El Shafie, Ahmed da Costa, Daniel Benevides Duong, Trung Q. Tuan, Hoang Duong Marshall, Alan Queens Univ Belfast Sch Elect Elect Engn & Comp Sci Belfast BT7 1NN Antrim North Ireland Qualcomm Inc San Diego CA 92121 USA Fed Univ Ceara UFC Dept Comp Engn BR-62010560 Sobral Brazil Univ Technol Sydney Sch Elect & Data Engn Ultimo NSW 2007 Australia Univ Liverpool Dept Elect Engn & Elect Liverpool L69 3GJ Merseyside England

We consider a multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) network in which a source node, Alice, communicates with an energy-harvesting destination node, Bob, in the presence of a passive eavesdropper. To secure the wireless transmission, Alice generates a hybrid artificial noise (AN) in both frequency and time domains. Moreover, in order to collect more energy, Bob splits the received signal power of the cyclic prefix of each OFDM block. We then propose two non-convex optimization problems to balance both the need for security and the need for harvesting energy at Bob. While one considers maximizing the secrecy rate, the other approach aims at maximizing the harvested energy. path-following algorithms of low computational complexity are developed and evaluated. Our numerical results show the gain of our proposed scheme and the effectiveness of our proposed algorithms.

关键词： MIMO OFDM SWIPT security energy harvesting hybrid artificial noise path-following algorithms

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PLS for Wireless Interference Networks in the Short Blocklength Regime with Strong Wiretap Channels

PLS for Wireless Interference Networks in the Short Blocklen...

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IEEE Global Communications Conference (GLOBECOM) on Advanced Technology for 5G Plus

作者： Sheng, Zhichao Tuan, Hoang D. Nasir, Ali A. Poor, H. Vincent Shanghai Univ Key Lab Specialty Fiber Opt & Opt Access Networks Joint Int Res Lab Specialty Fiber Opt & Adv Commu Shanghai Peoples R China Univ Technol Sch Elect & Data Engn Sydney NSW 2007 Australia King Fahd Univ Petr & Minerals KFUPM Dept Elect Engn Dhahran Saudi Arabia Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

ISBN: (纸本)9781728182988

This paper considers a wireless interference network in which the communication between multiple transmitter-user pairs is overheard by multiple eavesdroppers (EVs). Based on knowledge of the channel distribution, the goal is to maximize the worst users' secrecy rate under both long (infinite) blocklength and short (finite) blocklength transmissions. Under long blocklength transmission, the performance of the existing algorithms is unsatisfactory when the wiretapped channels are sufficiently strong. To address this drawback, we adopt a time-fraction based information and artificial noise (AN) transmission, under which first the information is transmitted within the initial fraction of the time slot and then AN is transmitted within the remaining fraction. Accordingly, the problem of join optimization of the time fractions, transmit power, and AN power to maximize the minimum secrecy rate is proposed and computed by a path-following algorithm, which iterates feasible points and converges at least to a locally optimal solution. A similar problem under short blocklength transmission is also proposed and computed. The provided simulations results clearly show the merits of the proposed approach.

关键词： URLLC interfering network secure communication outage probability path-following algorithms

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Beamforming Optimization for Physical Layer Security in MISO Wireless Networks

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2018年第14期66卷 3710-3723页

作者： Sheng, Zhichao Hoang Duong Tuan Duong, Trung Q. Poor, H. Vincent Univ Technol Sydney Sch Elect & Data Engn Sydney NSW 2007 Australia Queens Univ Belfast Belfast BT7 1NN Antrim North Ireland Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

A wireless network of multiple transmitter-user pairs overheard by an eavesdropper, where the transmitters are equippedwith multiple antennas, while the users and eavesdropper are equipped with a single antenna, is considered. At different levels of wireless channel knowledge, the problem of interest is beamforming to optimize the users' quality-of-service (QoS) in terms of their secrecy throughputs or maximize the network's energy efficiency under users' QoS. All these problems are seen as very difficult optimization problems with many nonconvex constraints and nonlinear equality constraints in beamforming vectors. The paper develops path-following computational procedures of low complexity and rapid convergence for the optimal beamforming solution. Their practicability is demonstrated through numerical examples.

关键词： Multi-input single-output network secure communication energy-efficient communication beamforming path-following algorithms

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Power Allocation for Energy Efficiency and Secrecy of Wireless Interference Networks

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2018年第6期17卷 3737-3751页

作者： Sheng, Zhichao Tuan, Hoang Duong Nasir, Ali Arshad Duong, Trung Q. Poor, H. Vincent Univ Technol Sydney Sch Elect & Data Engn Ultimo NSW 2007 Australia King Fahd Univ Petr & Minerals Dept Elect Engn Dhahran 31261 Saudi Arabia Queens Univ Belfast Belfast BT7 1NN Antrim North Ireland Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

Considering a multi-user interference network with an eavesdropper, this paper aims at the power allocation to optimize the worst secrecy throughput among the network links or the secure energy efficiency in terms of achieved secrecy throughput per Joule under link security requirements. Three scenarios for the access of channel state information are considered: the perfect channel state information;partial channel state information with channels from the transmitters to the eavesdropper exponentially distributed;and not perfectly known channels between the transmitters and the users with exponentially distributed errors. The paper develops various path-following procedures of low complexity and rapid convergence for the optimal power allocation. Their effectiveness and viability are illustrated through numerical examples. The power allocation schemes are shown to achieve both high secrecy throughput and energy efficiency.

关键词： Interference network secure communication energy-efficient communication power allocation path-following algorithms

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Outage-Aware Secure Beamforming in MISO Wireless Interference Networks

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IEEE SIGNAL PROCESSING LETTERS 2018年第7期25卷 956-960页

作者： Sheng, Zhichao Hoang Duong Tuan Duong, Trung Q. Poor, H. Vincent Univ Technol Sydney Sch Elect & Data Engn Broadway NSW 2007 Australia Queens Univ Belfast Belfast BT7 1NN Antrim North Ireland Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

Based on the knowledge of the channel distributions of a multi-input single-output wireless network of multiple transmitter-user pairs overheard by an eavesdropper, this letter develops an outage-aware beamforming design to optimize the users' quality-of-service (QoS) in terms of their secrecy rates. This is a very computationally difficult problem with a nonconcave objective function and nonlinear equality constraints in beamforming vectors. A path-following algorithm of low-complexity and rapid convergence is proposed for computation, which is also extended to solving the problem of maximizing the network's secure energy efficiency under users' QoS constraints. Numerical examples are provided to verify the efficiency of the proposed algorithms.

关键词： Energy-efficient communication interference networks outage-aware beamforming path-following algorithms secure communication

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Joint Power Allocation and Beamforming for Energy-Efficient Two-Way Multi-Relay Communications

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2017年第10期16卷 6660-6671页

作者： Sheng, Zhichao Tuan, Hoang Duong Duong, Trung Q. Poor, H. Vincent Univ Technol Sydney Fac Engn & Informat Technol Ultimo NSW 2007 Australia Queens Univ Belfast Belfast BT7 1NN Antrim North Ireland Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

This paper considers the joint design of user power allocation and relay beamforming in relaying communications, in which multiple pairs of single-antenna users exchange information with each other via multiple-antenna relays in two time slots. All users transmit their signals to the relays in the first time slot while the relays broadcast the beamformed signals to all users in the second time slot. The aim is to maximize the system's energy efficiency (EE) subject to quality-of-service (QoS) constraints in terms of exchange throughput requirements. The QoS constraints are nonconvex with many nonlinear cross-terms, so finding a feasible point is already computationally challenging. The sum throughput appears in the numerator while the total consumption power appears in the denominator of the EE objective function. The former is a nonconcave function and the latter is a nonconvex function, making fractional programming useless for EE optimization. Nevertheless, efficient iterations of low complexity to obtain its optimized solutions are developed. The performance of the multiple-user and multiple-relay networks under various scenarios is evaluated to show the merit of the proposed method.

关键词： Two-way relaying information exchange (IE) energy efficiency (EE) quality-of-service (QoS) relay beam-forming power allocation joint optimization path-following algorithms

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