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基于注水方法与粒子群的多用户OFDM资源分配 被引量:1
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作者 孙明 吴仁超 徐耀群 《哈尔滨商业大学学报(自然科学版)》 CAS 2015年第2期210-214,231,共6页
针对各态历经信道下多用户OFDM资源分配的用户速率加权和最大化问题,提出了一种新注水方法,能够快速和准确地得到最优子载波分配和最优功率分配;根据Karush-Kuhn-Tucker(KKT)最优性条件,采用粒子群算法对速率阈值乘子进行调整,最大化了... 针对各态历经信道下多用户OFDM资源分配的用户速率加权和最大化问题,提出了一种新注水方法,能够快速和准确地得到最优子载波分配和最优功率分配;根据Karush-Kuhn-Tucker(KKT)最优性条件,采用粒子群算法对速率阈值乘子进行调整,最大化了满足用户速率阈值限制的用户速率加权和.通过对所提算法与随机对偶梯度算法的分析比较发现,所提算法能够更好地满足KKT最优性条件,从而有利于找到最优解.仿真结果表明,本算法所得到的用户速率加权和高于随机对偶梯度算法. 展开更多
关键词 ofdm资源分配 注水方法 KKT最优性条件 粒子群算法
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认知无线电系统中OFDM多用户资源分配算法 被引量:15
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作者 李维英 陈东 +1 位作者 邢成文 王宁 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2007年第3期368-372,共5页
基于认知无线电技术特点和OFDM传输特性,提出一种OFDM多用户资源分配算法.认知无线电用户根据感知的资源状况,针对用户的带宽以及QOS等要求,通过对子载波和功率的分配使得整个信道容量达到最大.本算法引入“调度因子”来体现用户子载波... 基于认知无线电技术特点和OFDM传输特性,提出一种OFDM多用户资源分配算法.认知无线电用户根据感知的资源状况,针对用户的带宽以及QOS等要求,通过对子载波和功率的分配使得整个信道容量达到最大.本算法引入“调度因子”来体现用户子载波分配过程中“比例公平”的原则,保障每个用户都能满足一定的通信要求;引入“衰减因子”和用户设备类型,在不干扰授权用户通信的前提下进行多用户之间分配子载波和功率.算法采用“二步法”,以降低计算复杂度,满足于认知无线电实时性要求.仿真结果表明所提算法相对于FDMA方案信道容量至少提高40%. 展开更多
关键词 认知无线电 ofdm)资源分配
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基于进化算法和KKT条件的正交频多用技术(OFDM)资源优化分配方案设计 被引量:1
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作者 任新 《科学技术与工程》 北大核心 2013年第36期10828-10833,共6页
为了有效改善OFDM资源分配过程中传统二步法的求解性能,提高求解的准确性,提出了一种基于进化算法和KKT(Karush-Kuhn-Tucker)条件的正交频分多用技术(orbogonal frequeney division multiplening,OFDM)资源混合优化分配方案。首先在一... 为了有效改善OFDM资源分配过程中传统二步法的求解性能,提高求解的准确性,提出了一种基于进化算法和KKT(Karush-Kuhn-Tucker)条件的正交频分多用技术(orbogonal frequeney division multiplening,OFDM)资源混合优化分配方案。首先在一定规则下产生出子载波分配方案,在通过KKT条件给出较优的功率分配方案,计算对应的系统容量值,并作为适应值,把每个载波分配方案作为一条染色体,经过交叉、变异,得到一组新的载波分配方案。再用KKT条件对每一个新的载波分配方案求出相应的一种较优的功率分配方式,并得到相应的系统容量值。将上述过程交替进行,即可实现载波分配的优化信息和功率分配的优化信息彼此利用,达到混合优化求解,提高准确性的目的。经过实验仿真分析表明,该方案在多用户条件下与传统的MPSO、PFPA方案相比,在系统容量、最小发射功率、系统总传输速率等方面有明显的优势。 展开更多
关键词 正交频分多用技术(ofdm)资源分配 进化算法 KKT条件 优化
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Resource Allocation for Two-Way Amplify and Forward OFDM Relay Networks 被引量:3
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作者 Zhijun Liu Xiaofeng Tao Waheed ur Rehman 《China Communications》 SCIE CSCD 2017年第8期76-82,共7页
Physical-layer network coding(PNC) promises substantial theoretical gain to achieve the maximum system throughput in cooperative relay transmission. However, with the increasing global warming, how to reduce power con... Physical-layer network coding(PNC) promises substantial theoretical gain to achieve the maximum system throughput in cooperative relay transmission. However, with the increasing global warming, how to reduce power consumption while satisfy system throughput requirement is becoming a vital issue. In this paper, we investigate energy-efficiency resource allocation(RA) based on PNC with amplify-and-forward(AF) protocol in orthogonal frequency division multiple(OFDM) bidirectional transmission. To minimize the overall transmit power consumption with required system throughput requirement, we consider joint subcarriers and power allocation and formulate the objective task into a constrained optimization problem where the best relay node is selected to minimize total transmit power. The closed form optimization power allocation solutions are acquired by analytical derivation. Based on derivation, we propose a novel optimal energy-efficient power allocation(OE-PA). Numerical results are given to evaluate the performance of the derived scheme as compared to other schemes and show that our scheme has signifi cant improvement to energy saving. 展开更多
关键词 Energy-effi ciency Resource allocation physical-layer network coding ofdm system
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Adaptive resource allocation for multi-user multi-server power-line communication OFDM systems
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作者 徐志强 翟明岳 +1 位作者 崔翔 赵宇明 《Journal of Central South University》 SCIE EI CAS 2011年第2期479-489,共11页
The bits and power allocation model of adaptive power-rate mixture for multi-user multi-server power-line communication systems was analyzed with the restrictions of maximal total power,fixed rate for each real time (... The bits and power allocation model of adaptive power-rate mixture for multi-user multi-server power-line communication systems was analyzed with the restrictions of maximal total power,fixed rate for each real time (RT) user,minimal rate for each non-real time (NRT) user,maximal bits and power for each subcarrier in each orthogonal frequency division multiplexing (OFDM) symbol. An algorithm of resource dynamic allocation in the first OFDM symbol of each frame and resource optimal adjustment in the latter OFDM symbol of each frame was proposed. In the first OFDM symbol of every frame,resource is firstly assigned for RT users so as to minimize their total used power until satisfying their fixed rates; secondly the remainder resource of power and subcarriers are assigned for NRT users so as to minimize their total used power until satisfying their minimal rates also; lastly the remainder resource is again assigned for NRT users according to the proportional fairness strategy so as to maximize their total assigning rate. In the latter OFDM symbol of each frame,bits are swapped and power is adjusted for every user based on the resource allocation results of anterior OFDM symbol. The algorithm is tested in the typical power-line channel scenarios and the simulation results indicate that the proposed algorithm has better performances than the classical multi-user resource allocation algorithms and it realizes the multiple aims of multi-user multi-server resource allocation for power-line communication systems. 展开更多
关键词 power-line communications adaptive orthogonal frequency division multiplexing resource allocation user priority swapadjustment
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