Abstract:We investigate the optimal joint power allocation in Heterogeneous Networks(HetNets)to maximise its capacity.Considering frequency reuse in the network,we study two power-constraint cases,i.e.,per-cell power ...Abstract:We investigate the optimal joint power allocation in Heterogeneous Networks(HetNets)to maximise its capacity.Considering frequency reuse in the network,we study two power-constraint cases,i.e.,per-cell power constraint case and per-tier power constraint case.We formulate the capacity maximization problem by allowing each subcarrier of Marco eNodeB(MeNB)to be shared by users from multiple Picos.We mathematically demonstrate that the optimal power allocation in the per-cell power constraint case has a remarkably simple nature:each Pico transmits to its user with maximum power,while MeNB either selects only one user to jointly transmit with maximum power or does not transmit to any user.In the per-tier power constraint case,the difference is that the power allocation between two Picos takes the form of water-filling.Numerical results verify that our proposed schemes outperform the conventional interference coordination schemes.展开更多
Power allocation is an important issue for Cognitive Radio Networks(CRNs),since it needs to consider the Quality of Service(QoS) for Secondary Users(SUs) while maintaining the interference power to Primary User(PU) be...Power allocation is an important issue for Cognitive Radio Networks(CRNs),since it needs to consider the Quality of Service(QoS) for Secondary Users(SUs) while maintaining the interference power to Primary User(PU) below the Interference Temperature(IT) threshold. In this paper, based on Euclidean projection, we propose a distributed power control algorithm with QoS requirements to minimise the total power consumption of SUs under the time-varying channel scenario. Considering the maximum transmit power constraints and the minimum signal to interference plus noise constraints for each SU, together with the IT constraints for each PU, the power allocation problem is transformed into a convex optimization problem without auxiliary variables, and is solved by the Lagrangian dual method with less information exchange.Simulation results demonstrate that the proposed scheme is superior to the Iterative Water-Filling Algorithm(IWFA).展开更多
针对单中继AF协作通信系统,分析了不同中继位置和功率分配方式对系统误码率性能的影响。以最小化系统误码率为目标,研究了等功率分配(equal power allocation,EPA)和最优功率分配(optimum power allocation,OPA)两种方案下,中继按照线...针对单中继AF协作通信系统,分析了不同中继位置和功率分配方式对系统误码率性能的影响。以最小化系统误码率为目标,研究了等功率分配(equal power allocation,EPA)和最优功率分配(optimum power allocation,OPA)两种方案下,中继按照线形拓扑轨迹运动时的最优位置。理论分析和仿真结果表明,中继位置及OPA的联合优化算法大大提高了传统的EPA方案下的系统性能。展开更多
在中继端运动与静止两种情况下分析了一个两用户放大转发协同通信系统的误码率(symbol-error-rate,SER)性能。首先得到M-PSK调制下的SER封闭表达式与相应上界,以此提出一个最优功率分配方案(optimum power allocation,OPA),目的是使得SE...在中继端运动与静止两种情况下分析了一个两用户放大转发协同通信系统的误码率(symbol-error-rate,SER)性能。首先得到M-PSK调制下的SER封闭表达式与相应上界,以此提出一个最优功率分配方案(optimum power allocation,OPA),目的是使得SER最小,然后讨论了在最优与等功率分配(equal power allocation,EPA)两种方案下中继按照椭圆拓扑运动时对SER的影响。EPA方案下,精确最优中继位置恰在源端与目的端的中点处,但是在OPA方案下最优位置却离目的端更近,并且,无论中继端运动还是静止,OPA方案都能得到比EPA更好的SER性能。展开更多
基金supported by the National Major Science and Technology Project under Grant No.2009ZX03003-003-01Huawei Innovation Project under Grant No.YJCB2011060WL
文摘Abstract:We investigate the optimal joint power allocation in Heterogeneous Networks(HetNets)to maximise its capacity.Considering frequency reuse in the network,we study two power-constraint cases,i.e.,per-cell power constraint case and per-tier power constraint case.We formulate the capacity maximization problem by allowing each subcarrier of Marco eNodeB(MeNB)to be shared by users from multiple Picos.We mathematically demonstrate that the optimal power allocation in the per-cell power constraint case has a remarkably simple nature:each Pico transmits to its user with maximum power,while MeNB either selects only one user to jointly transmit with maximum power or does not transmit to any user.In the per-tier power constraint case,the difference is that the power allocation between two Picos takes the form of water-filling.Numerical results verify that our proposed schemes outperform the conventional interference coordination schemes.
基金supported by the National Natural Science Foundation of China under Grant No.61171079
文摘Power allocation is an important issue for Cognitive Radio Networks(CRNs),since it needs to consider the Quality of Service(QoS) for Secondary Users(SUs) while maintaining the interference power to Primary User(PU) below the Interference Temperature(IT) threshold. In this paper, based on Euclidean projection, we propose a distributed power control algorithm with QoS requirements to minimise the total power consumption of SUs under the time-varying channel scenario. Considering the maximum transmit power constraints and the minimum signal to interference plus noise constraints for each SU, together with the IT constraints for each PU, the power allocation problem is transformed into a convex optimization problem without auxiliary variables, and is solved by the Lagrangian dual method with less information exchange.Simulation results demonstrate that the proposed scheme is superior to the Iterative Water-Filling Algorithm(IWFA).
文摘针对单中继AF协作通信系统,分析了不同中继位置和功率分配方式对系统误码率性能的影响。以最小化系统误码率为目标,研究了等功率分配(equal power allocation,EPA)和最优功率分配(optimum power allocation,OPA)两种方案下,中继按照线形拓扑轨迹运动时的最优位置。理论分析和仿真结果表明,中继位置及OPA的联合优化算法大大提高了传统的EPA方案下的系统性能。
文摘在中继端运动与静止两种情况下分析了一个两用户放大转发协同通信系统的误码率(symbol-error-rate,SER)性能。首先得到M-PSK调制下的SER封闭表达式与相应上界,以此提出一个最优功率分配方案(optimum power allocation,OPA),目的是使得SER最小,然后讨论了在最优与等功率分配(equal power allocation,EPA)两种方案下中继按照椭圆拓扑运动时对SER的影响。EPA方案下,精确最优中继位置恰在源端与目的端的中点处,但是在OPA方案下最优位置却离目的端更近,并且,无论中继端运动还是静止,OPA方案都能得到比EPA更好的SER性能。
