Low earth orbit(LEO)satellites with wide coverage can carry the mobile edge computing(MEC)servers with powerful computing capabilities to form the LEO satellite edge computing system,providing computing services for t...Low earth orbit(LEO)satellites with wide coverage can carry the mobile edge computing(MEC)servers with powerful computing capabilities to form the LEO satellite edge computing system,providing computing services for the global ground users.In this paper,the computation offloading problem and resource allocation problem are formulated as a mixed integer nonlinear program(MINLP)problem.This paper proposes a computation offloading algorithm based on deep deterministic policy gradient(DDPG)to obtain the user offloading decisions and user uplink transmission power.This paper uses the convex optimization algorithm based on Lagrange multiplier method to obtain the optimal MEC server resource allocation scheme.In addition,the expression of suboptimal user local CPU cycles is derived by relaxation method.Simulation results show that the proposed algorithm can achieve excellent convergence effect,and the proposed algorithm significantly reduces the system utility values at considerable time cost compared with other algorithms.展开更多
Satellite-terrestrial spectrum sharing can effectively alleviate the scarcity of spectrum resources,which is a widely concerned issue in the academic community,and thus have received great attention.In this paper,cons...Satellite-terrestrial spectrum sharing can effectively alleviate the scarcity of spectrum resources,which is a widely concerned issue in the academic community,and thus have received great attention.In this paper,considering the delay-limited transmission mode,we investigate a hybrid satellite-terrestrial network and propose a spectrum sharing scheme to increase the spectrum efficiency by sharing spectrum resources both between various networks on the condition of interference constraints and within one network by enabling non-orthogonal multiple access.The feasibility of spectrum sharing is first analyzed,which is also the theoretical foundation of our proposed scheme.Afterwards,by employing the Shadowed-Rician fading,we evaluate its performance,while realistically taking the mutual interferences between terrestrial and satellite networks into consideration.In addition,these theoretical derivation results are used for power allocation to maximize the system throughput by tedious algebraic operations.Finally,we validate the superiority of our proposed spectrum sharing scheme and the proposed power allocation method through numerical simulation.展开更多
基金supported by National Natural Science Foundation of China No.62231012Natural Science Foundation for Outstanding Young Scholars of Heilongjiang Province under Grant YQ2020F001Heilongjiang Province Postdoctoral General Foundation under Grant AUGA4110004923.
文摘Low earth orbit(LEO)satellites with wide coverage can carry the mobile edge computing(MEC)servers with powerful computing capabilities to form the LEO satellite edge computing system,providing computing services for the global ground users.In this paper,the computation offloading problem and resource allocation problem are formulated as a mixed integer nonlinear program(MINLP)problem.This paper proposes a computation offloading algorithm based on deep deterministic policy gradient(DDPG)to obtain the user offloading decisions and user uplink transmission power.This paper uses the convex optimization algorithm based on Lagrange multiplier method to obtain the optimal MEC server resource allocation scheme.In addition,the expression of suboptimal user local CPU cycles is derived by relaxation method.Simulation results show that the proposed algorithm can achieve excellent convergence effect,and the proposed algorithm significantly reduces the system utility values at considerable time cost compared with other algorithms.
基金supported by National Natural Science Foundation of China No.62231012National Key Research and Development Program of China under Grant 2021YFB2900500+1 种基金National 2011 Collaborative Innovation Center of Wireless Communication Technologies under Grant 2242022k60006Heilongjiang Province Postdoctoral General Foundation under Grant LBH-Z22133.
文摘Satellite-terrestrial spectrum sharing can effectively alleviate the scarcity of spectrum resources,which is a widely concerned issue in the academic community,and thus have received great attention.In this paper,considering the delay-limited transmission mode,we investigate a hybrid satellite-terrestrial network and propose a spectrum sharing scheme to increase the spectrum efficiency by sharing spectrum resources both between various networks on the condition of interference constraints and within one network by enabling non-orthogonal multiple access.The feasibility of spectrum sharing is first analyzed,which is also the theoretical foundation of our proposed scheme.Afterwards,by employing the Shadowed-Rician fading,we evaluate its performance,while realistically taking the mutual interferences between terrestrial and satellite networks into consideration.In addition,these theoretical derivation results are used for power allocation to maximize the system throughput by tedious algebraic operations.Finally,we validate the superiority of our proposed spectrum sharing scheme and the proposed power allocation method through numerical simulation.
