针对电力线通信的限制条件,探讨在每自适应正交频分复用(orthogonal frequency division multiplexing,OFDM)符号内各用户要求速率、各子信道分配最大功率和比特数约束下,多用户在多子信道上自适应比特和功率分配的数学模型,提出2种新...针对电力线通信的限制条件,探讨在每自适应正交频分复用(orthogonal frequency division multiplexing,OFDM)符号内各用户要求速率、各子信道分配最大功率和比特数约束下,多用户在多子信道上自适应比特和功率分配的数学模型,提出2种新的基于用户优先级的功率自适应动态资源分配算法,其不同之处是,多用户在同频子信道下功率分配时,一是基于Perron-Frobenius理论,另一是基于非合作博弈论。在典型电力线信道环境下仿真分析算法的性能,并分析干扰因子和定价因子对算法性能的影响。结果表明,基于非合作博弈论的资源分配算法可以通过定价因子的改变来控制分配的功率过大等问题,从而能更好地满足电力线通信系统中高速率、低功耗和低复杂度的要求。展开更多
Cognitive radio allows Secondary Users (SUs) to dynamically use the spectrum resource licensed to Prirmry Users (PUs), and significantly improves the efficiency of spectrum utilization and is viewed as a promising...Cognitive radio allows Secondary Users (SUs) to dynamically use the spectrum resource licensed to Prirmry Users (PUs), and significantly improves the efficiency of spectrum utilization and is viewed as a promising technology. In cognitive radio networks, the problem of power control is an important issue. In this paper, we mainly focus on the problem of power control for fading channels in cognitive radio networks. The spectrum sharing underlay scenario is considered, where SUs are allowed to coexist with PUs on the condition that the outage probability of PUs is below the maximum outage probability threshold limitation due to the interference caused by SUs. Moreover, besides the outage probability threshold which is defined to protect the performance of PUs, we also consider the maximum transmit power constraints for each SU. With such a setup, we emphasize the problem of power control to minimize the outage probability of each SU in fading channels. Then, based on the statistical information of the fading channel, the closed expression for outage probability is given in fading channels. The Dual-Iteration Power Control (DIPC) algorithm is also proposed to minimize the outage probability based on Perron-Frobenius theory and gradient descent method under the constraint condition. Finally, simulation results are illustrated to demonstrate the performance of the proposed scheme.展开更多
文摘针对电力线通信的限制条件,探讨在每自适应正交频分复用(orthogonal frequency division multiplexing,OFDM)符号内各用户要求速率、各子信道分配最大功率和比特数约束下,多用户在多子信道上自适应比特和功率分配的数学模型,提出2种新的基于用户优先级的功率自适应动态资源分配算法,其不同之处是,多用户在同频子信道下功率分配时,一是基于Perron-Frobenius理论,另一是基于非合作博弈论。在典型电力线信道环境下仿真分析算法的性能,并分析干扰因子和定价因子对算法性能的影响。结果表明,基于非合作博弈论的资源分配算法可以通过定价因子的改变来控制分配的功率过大等问题,从而能更好地满足电力线通信系统中高速率、低功耗和低复杂度的要求。
文摘Cognitive radio allows Secondary Users (SUs) to dynamically use the spectrum resource licensed to Prirmry Users (PUs), and significantly improves the efficiency of spectrum utilization and is viewed as a promising technology. In cognitive radio networks, the problem of power control is an important issue. In this paper, we mainly focus on the problem of power control for fading channels in cognitive radio networks. The spectrum sharing underlay scenario is considered, where SUs are allowed to coexist with PUs on the condition that the outage probability of PUs is below the maximum outage probability threshold limitation due to the interference caused by SUs. Moreover, besides the outage probability threshold which is defined to protect the performance of PUs, we also consider the maximum transmit power constraints for each SU. With such a setup, we emphasize the problem of power control to minimize the outage probability of each SU in fading channels. Then, based on the statistical information of the fading channel, the closed expression for outage probability is given in fading channels. The Dual-Iteration Power Control (DIPC) algorithm is also proposed to minimize the outage probability based on Perron-Frobenius theory and gradient descent method under the constraint condition. Finally, simulation results are illustrated to demonstrate the performance of the proposed scheme.