In this paper,a new communication model is built named grouping D2D(GD2D).Different from the traditional D2D coordination,we proposed GD2D communication in licensed and unlicensed spectrum simultaneously.We formulate ...In this paper,a new communication model is built named grouping D2D(GD2D).Different from the traditional D2D coordination,we proposed GD2D communication in licensed and unlicensed spectrum simultaneously.We formulate a resource allocation problem,which aims at maximizing the energy efficiency(EE)of the system while guaranteeing the quality-of-service(Qos)of users.To efficiently solve this problem,the non-convex optimization problem is first transformed into a convex optimization problem.By transforming the fractional-form problem into an equivalent subtractive-form problem,an iterative power allocation algorithm is proposed to maximize the system EE.Moreover,the optimal closedform power allocation expressions are derived by the Lagrangian approach.Simulation results show that our algorithm achieves higher EE performance than the traditional D2D communication scheme.展开更多
The resource allocation for device-to-device(D2D)multicast communications is investigated.To achieve fair energy efficiency(EE)among different multicast groups,the max-min fairness criterion is used as the optimizatio...The resource allocation for device-to-device(D2D)multicast communications is investigated.To achieve fair energy efficiency(EE)among different multicast groups,the max-min fairness criterion is used as the optimization criterion and the EE of D2D multicast groups are taken as the optimization objective function.The aim is to maximize the minimum EE for different D2D multicast groups under the constraints of the maximum transmit power and minimum transmit rate,which is modeled as a non-convex and mixed-integer fractional programming problem.Here,suboptimal resource allocation algorithms are proposed to solve this problem.First,channel assignment scheme is performed to assign channel to D2D multicast groups.Second,for a given channel assignment,iterative power allocation schemes with and without loss of cellular users’rate are completed,respectively.Simulation results corroborate the convergence performance of the proposed algorithms.In addition,compared with the traditional throughput maximization algorithm,the proposed algorithms can improve the energy efficiency of the system and the fairness achieved among different multicast groups.展开更多
The status quo of resource allocation of agricultural science and technology R&D(research and development)both at home and abroad,including the amount and function of agricultural science and technology research f...The status quo of resource allocation of agricultural science and technology R&D(research and development)both at home and abroad,including the amount and function of agricultural science and technology research funds,human resources in the resources of agricultural science and technology R&D,the efficiency of resource allocation of agricultural science and technology R&D,the management system of agricultural scientific innovation and the operation status of scientific funds,is analyzed.The problems in the current resource allocation of agricultural science and technology R&D are put forward,including unreasonable resource allocation;low efficiency,and low efficiency of the transformation of agricultural scientific achievements.The highly effective resource allocation of agricultural science and technology R&D is analyzed from the aspects of resource allocation structure,environment,channel,spatial layout and industrial chain.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant no.61473066 and Grant no.61601109in part by the Fundamental Research Funds for the Central Universities under Grant No.N152305001.
文摘In this paper,a new communication model is built named grouping D2D(GD2D).Different from the traditional D2D coordination,we proposed GD2D communication in licensed and unlicensed spectrum simultaneously.We formulate a resource allocation problem,which aims at maximizing the energy efficiency(EE)of the system while guaranteeing the quality-of-service(Qos)of users.To efficiently solve this problem,the non-convex optimization problem is first transformed into a convex optimization problem.By transforming the fractional-form problem into an equivalent subtractive-form problem,an iterative power allocation algorithm is proposed to maximize the system EE.Moreover,the optimal closedform power allocation expressions are derived by the Lagrangian approach.Simulation results show that our algorithm achieves higher EE performance than the traditional D2D communication scheme.
基金Projects(61801237,61701255)supported by the National Natural Science Foundation of ChinaProject(SBH17024)supported by the Postdoctoral Science Foundation of Jiangsu Province,China+2 种基金Project(15KJB510026)supported by the Natural Science Foundation of the Jiangsu Higher Education Institutions,ChinaProject(BK20150866)supported by the Natural Science Foundation of Jiangsu Province,ChinaProjects(NY215046,NY217056)supported by the Introduction of Talent Fund of Nanjing University of Posts and Telecommunications,China
文摘The resource allocation for device-to-device(D2D)multicast communications is investigated.To achieve fair energy efficiency(EE)among different multicast groups,the max-min fairness criterion is used as the optimization criterion and the EE of D2D multicast groups are taken as the optimization objective function.The aim is to maximize the minimum EE for different D2D multicast groups under the constraints of the maximum transmit power and minimum transmit rate,which is modeled as a non-convex and mixed-integer fractional programming problem.Here,suboptimal resource allocation algorithms are proposed to solve this problem.First,channel assignment scheme is performed to assign channel to D2D multicast groups.Second,for a given channel assignment,iterative power allocation schemes with and without loss of cellular users’rate are completed,respectively.Simulation results corroborate the convergence performance of the proposed algorithms.In addition,compared with the traditional throughput maximization algorithm,the proposed algorithms can improve the energy efficiency of the system and the fairness achieved among different multicast groups.
基金Supported by Agricultural Scientific Development Projects of Hebei Provincial Science & Technology Department(2010016272)Development Economics Projects of Provincial Excellent Courses in Agricultural University of HebeiPhilosophy and Social Science Research Projects in Hebei Province
文摘The status quo of resource allocation of agricultural science and technology R&D(research and development)both at home and abroad,including the amount and function of agricultural science and technology research funds,human resources in the resources of agricultural science and technology R&D,the efficiency of resource allocation of agricultural science and technology R&D,the management system of agricultural scientific innovation and the operation status of scientific funds,is analyzed.The problems in the current resource allocation of agricultural science and technology R&D are put forward,including unreasonable resource allocation;low efficiency,and low efficiency of the transformation of agricultural scientific achievements.The highly effective resource allocation of agricultural science and technology R&D is analyzed from the aspects of resource allocation structure,environment,channel,spatial layout and industrial chain.