Dear Editor,This letter is concerned with the problem of stable high-quality signal transmission of unmanned aerial vehicle(UAV)-assisted multiple-input multiple-output(MIMO)communication system.The particle swarm opt...Dear Editor,This letter is concerned with the problem of stable high-quality signal transmission of unmanned aerial vehicle(UAV)-assisted multiple-input multiple-output(MIMO)communication system.The particle swarm optimization(PSO)algorithm is used to achieve optimal beamforming and power allocation for this system.Additionally,sensitive particle(SP)and parameter adaptive adjustment are introduced into the traditional PSO algorithm,aiming to improve the performance of the PSO algorithm in dynamic environments with real-time changes in the UAV position.A reinforcement learning(RL)-based approach is proposed to obtain optimal UAV trajectory and adaptive adjustment strategy for PSO parameters,which combine with a specific obstacle avoidance scheme to achieve accurate UAV navigation while satisfying high-quality signal transmission.Simulation experiments show that our scheme provides higher and more stable spectral efficiency as well as more efficient UAV navigation than the currently commonly used scheme with a single RL approach.展开更多
To improve the optical performance of an antireflection(AR) coating on a micro-spherical substrate, the ray angle of the incidence distribution and the thickness profile are taken into consideration during the optic...To improve the optical performance of an antireflection(AR) coating on a micro-spherical substrate, the ray angle of the incidence distribution and the thickness profile are taken into consideration during the optical coating design. For a convex spherical substrate with a radius of curvature of 10 mm and a clear aperture of 10 mm,three strategies are used for the optimization of the spectral performance of a broadband AR coating in the spectral region from 480 to 720 nm. By comparing the calculated residual reflectance and spectral uniformity,the developed method demonstrates its superiority in spectral performance optimization of an AR coating on a micro-spherical substrate.展开更多
基金supported by the National Natural Science Foundation of China(62173251,62203113the“Zhishan”Scholars Programs of Southeast University,and the Fundamental Research Funds for the Central Universities(2242023K30034).
文摘Dear Editor,This letter is concerned with the problem of stable high-quality signal transmission of unmanned aerial vehicle(UAV)-assisted multiple-input multiple-output(MIMO)communication system.The particle swarm optimization(PSO)algorithm is used to achieve optimal beamforming and power allocation for this system.Additionally,sensitive particle(SP)and parameter adaptive adjustment are introduced into the traditional PSO algorithm,aiming to improve the performance of the PSO algorithm in dynamic environments with real-time changes in the UAV position.A reinforcement learning(RL)-based approach is proposed to obtain optimal UAV trajectory and adaptive adjustment strategy for PSO parameters,which combine with a specific obstacle avoidance scheme to achieve accurate UAV navigation while satisfying high-quality signal transmission.Simulation experiments show that our scheme provides higher and more stable spectral efficiency as well as more efficient UAV navigation than the currently commonly used scheme with a single RL approach.
文摘To improve the optical performance of an antireflection(AR) coating on a micro-spherical substrate, the ray angle of the incidence distribution and the thickness profile are taken into consideration during the optical coating design. For a convex spherical substrate with a radius of curvature of 10 mm and a clear aperture of 10 mm,three strategies are used for the optimization of the spectral performance of a broadband AR coating in the spectral region from 480 to 720 nm. By comparing the calculated residual reflectance and spectral uniformity,the developed method demonstrates its superiority in spectral performance optimization of an AR coating on a micro-spherical substrate.