|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | An Efficient Trajectory Planning for Cellular-Connected UAV under the Connectivity Constraint显示文摘Unmanned Aerial Vehicles(UAVs)acting as aerial users to access the cellular network form a promising solution to guarantee its safe and efficient operations via the high-quality communication.Due to the flexible mobility of UAVs and the coverage range limits of ground base station(GBS),the signalto-noise ratio(SNR)of the communication link between UAVs and GBS will fluctuate.It is an important requirement to maintain the UAV’s cellular connection to meet a certain SNR requirement during the mission for UAV flying from take off to landing.In this paper,we study an efficient trajectory planning method that can minimize a cellular-connected UAV’s mission completion time under the connectivity requirement.The conventional method to tackle this problem adopts graph theory or a dynamic programming method to optimize the trajectory,which generally incurs high computational complexities.Moreover,there is a nonnegligible performance gap compared to the optimal solution.To this end,we propose an iterative trajectory optimizing algorithm based on geometric planning.Firstly,we apply graph theory to obtain all the possible UAV-GBS association sequences and select the candidate association sequences based on the topological relationship among UAV and GBSs.Next,adopting the triangle inequality property,an iterative handover location design is proposed to determine the shortest flight trajectory with fast convergence and low computation complexity.Then,the best flight trajectory can be obtained by comparing all the candidate trajectories.Lastly,we revealed the tradeoff between mission completion time and flight energy consumption.Numerical results validate that our proposed solution can obtain the effectiveness with set accuracy and outperform against the benchmark schemes with affordable computation time. | Dingcheng Yang Qian Dan Lin Xiao Chuankuan Liu Laurie Cuthbert | 2021 | China Communications2021，18，2： | 3 |
| 2 | Optimal Power Control for OFDM Signals over Two-Way Relay with Physical Network Coding显示文摘This paper describes an optimal power allocation scheme for orthogonal frequency division multiple access two-way relay networks with physical network coding.The aim is to enhance the achievable sum rate of the terminals for a constrained total transmit power.Convex optimization is used to derive a closed-form solution for the power allocation between the relay node and the two terminals.This reduces the variable dimensionality of the objective function for the power assignment problem among multiple carriers when the total transmit power is constrained.This solution is then used to derive the optimal power control scheme.This method reduces the implementation complexity compared with the traditional resource allocation scheme.Numerical and simulation results show that the approach achieves almost the optimal sum rate and outperforms the fixed power assignment method with less computational load in various scenarios. | Dingcheng Yang Zhenghai Wang Hao He Jisheng Xu | 2011 | Tsinghua Science and Technology2011，16，6： | 1 |
| 3 | Joint power control and relay selection scheme for cognitive two-way relay networks显示文摘A joint power control and relay selection scheme is considered for a cooperative and cognitive radio system where a secondary network shares spectrum with the primary network. In the secondary network, two secondary users (SUs) communicate with each other via an assist relay. The main point is to provide the best system performance to SUs while maintaining the interference power at primary user (PU) under a certain level. Using convex optimization, a closed-form solution is obtained when optimizing the power allocation among the two nodes and relay. Based on this result, a joint power control and relay selection scheme with fewer variable dimensions is proposed to maximize the achievable rate of the secondary system. Simulation results demonstrate that the sum rate of the cognitive two-way relay network increases compared with a random relay selection and fixed power allocation. | Dingcheng Yang Lin Xiao Jisheng Xu Wengang Li | 2013 | Journal of Systems Engineering and Electronics2013，24，4： | 1 |
| 4 | Transmission strategies for wireless powered MIMO relay systems显示文摘This paper studies a multiple input multiple output(MIMO) simultaneous wireless information and power transfer(SWIPT) relay system, in which the source node(SN) send information and energy simultaneously to the relay node(RN), and the RN forward the received signal to the destination node(DN) powered by harvested energy. In particular, we consider two SWIPT receiver designs, namely power splitting(PS) and antenna switching(AS) in the relay system. For each design, iterative algorithms based on convex optimization technique are proposed to maximize the system rate. Furthermore, in order to strike a balance between computational complexity and system performance, based on the AS scheme, we propose a low complexity optimization method for PS scheme where a suboptimal PS ratio is given. Numerical results are provided to evaluate the performance of the proposed algorithm for MIMO SWIPT relay systems. It is shown that the performance of the proposed suboptimal method approaches that of the optimal PS scheme. | Wu Fahui Xiao Lin Yang Dingcheng Laurie Cuthbert | 2017 | The Journal of China Universities of Posts and Telecommunications2017，24，1： | 0 |
| 5 | Joint User Association and Caching Placement for Cache-Enabling UAV Networks显示文摘Cache-enabling unmanned aerial vehicles(UAVs)are considered for storing popular contents and providing downlink data offloading in cellular networks.In this context,we formulate a joint optimization problem of user association,caching placement,and backhaul bandwidth allocation for minimizing content acquisition delay with consideration of UAVs’energy constraint.We decompose the formulated problem into two subproblems:i)user association and caching placement and ii)backhaul bandwidth allocation.We first obtain the optimal bandwidth allocation with given user association and caching placement by the Lagrangian multiplier approach.After that,embedding the backhaul bandwidth allocation algorithm,we solve the user association and caching placement problem by a threedimensional(3D)matching method.Then we decompose it into two two-dimensional(2D)matching problems and develop low-complexity algorithms.The proposed scheme converges and exhibits a low computational complexity.Simulation results demonstrate that the proposed cache-enabling UAV framework outperforms the conventional UAV-assisted cellular networks in terms of content acquisition delay and the proposed scheme achieves significantly lower content acquisition delay compared with other two benchmark schemes. | Tiankui Zhang Chao Chen Dingcheng Yang | 2023 | China Communications2023，20，6： | 0 |
| 6 | 3D Radio Map Reconstruction and Trajectory Optimization for Cellular-Connected UAVs显示文摘This paper introduces an innovative approach to address the trajectory optimization challenge for cellular-connected unmanned aerial vehicles(UAVs)operating in three-dimensional(3D)space.In most cases,optimizing UAV trajectories necessitates ensuring reliable network connectivity.H.owever,achieving dependable connectivity in 3D space poses a significant challenge due to terrestrial base stations primarily designed for ground users.Additionally,UAVs possess network information only for the areas they have visited,with global network information being inaccessible.To address this issue,we propose a collaborative approach in which multiple UAVs create a global model of outage probability using federated learning,enabling more precise and effective trajectory design.Building upon the constructed global information,we conduct the trajectory design.Initially,we introduce A-star(A*)algorithm for trajectory design in small-scale scenarios.Nevertheless,recognizing the limitations of A*algorithm in large-scale scenarios,we further introduce improved rapidly-exploring random trees(RRTs)algorithm for weighted path optimization.Simulation results are provided to validate the effectiveness of the proposed algorithms. | Qiuhu Gong Fahui Wu Dingcheng Yang Lin Xiao Zemin Liu | 2023 | Journal of Communications and Information Networks2023，8，4： | 0 |
| 7 | Sum-rate maximization for UAV-enabled two-way relay systems显示文摘In this paper,an Unmanned Aerial Vehicle(UAV)-enabled two-way relay system with Physical-layer Network Coding(PNC)protocol is considered.A rotary-wing UAV is applied as a mobile relay to assist two ground terminals for information interaction.Our goal is to maximize the sum-rate of the two-way relay system subject to mobility constraints,propulsion power consumption constraints,and transmit power constraints.The formulated problem is not easy to solve directly because it is a mixed integer non-convex optimization problem.Therefore,we decompose it into three sub-problems,and use the mutation arithmetic of the Genetic Algorithm(GA)and Successive Convex Approximation(SCA)to dispose.Besides,a high-efficiency iterative algorithm is proposed to obtain a locally optimal solution by jointly optimizing the time slot pairing,the transmit power allocation,and the UAV trajectory design.Numerical results demonstrate that the proposed design achieves significant gains over the benchmark designs. | Keju Lu Fahui Wu Lin Xiao Yipeng Liang Dingcheng Yang | 2022 | Digital Communications and Networks2022，8，6： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员