有限字符输入DCO-OFDMA系统的资源分配算法研究  

Research on Resource Allocation Algorithm of DCO-OFDMA System with Finite-Alphabet Inputs

作　　者：李世银 鲁姗妹 马帅 张凡 徐子涵 王洪梅 李宗艳 熊海良[6] LI Shi-yin;LU Shan-mei;MA Shuai;ZHANG Fan;XU Zi-han;WANG Hong-mei;LI Zong-yan;XIONG Hai-liang(School of Information and Control Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;Engineering Research Center of Intelligent Control for Underground Space,Ministry of Education,Xuzhou,Jiangsu 221116,China;National Mobile Communications Research Laboratory,Southeast University,Nanjing,Jiangsu 210096,China;Shaanxi Key Laboratory of Information Communication Network and Security,Xi’an University of Posts&Telecommunications,Xi’an,Shaanxi 710121,China;Spreadtrum Communications Co.,Ltd.Communication Algorithm Technology Resources Department,Shanghai 201203,China;The School of Information Science and Engineering,Shandong University,Jinan,Shandong 250100,China)

机构地区：[1]中国矿业大学信息与控制工程学院,江苏徐州221116 [2]地下空间智能控制教育部工程研究中心,江苏徐州221116 [3]东南大学移动通信国家重点实验室,江苏南京210096 [4]西安邮电大学陕西省信息通信网络及安全重点实验室,陕西西安710121 [5]展讯通信有限公司通信算法技术资源部,上海201203 [6]山东大学信息科学与工程学院,山东济南250100

出　　处：《电子学报》2022年第3期574-584,共11页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61771474);山东省重大科技创新工程项目(No.2019JZZY020505);东南大学移动通信国家重点实验室开放研究基金资助课题(No.2021D02);山东省自然科学基金面上项目(No.ZR2019MF038)。

摘　　要：至今,有限字符输入可见光通信(Visible Light Communication,VLC)直流偏置光正交频分多址接入(Direct Current Biased Optical Orthogonal Frequency Division Multiplexing Access,DCO-OFDMA)系统的用户信息传输速率极限仍然未知.本文推导了有限字符输入DCO-OFDMA系统的用户准确可达速率及其下界,并研究了满足用户速率门限要求的总传输电功率最小化问题.由于原始优化问题为优化变量为子载波分配、功率分配及直流偏置的最小化总传输电功率的联合优化问题,复杂度高,难以求解,本文通过推导最优直流偏置及固定子载波分配方式将原始问题简化为优化变量为功率分配的最小化总信息传输功率的单变量优化问题,并利用拉格朗日函数、Karush-Kuhn-Tucker(KKT)条件,提出了满足用户速率门限要求的最小化总信息传输功率的功率分配方案.仿真结果表明,本文提出的功率分配方案依赖于子载波之间的信道增益差异和用户速率门限,且在低速率门限与高速率门限时效果均明显优于等功率分配方案,并且在高速率门限时效果明显优于传统注水功率分配方案.So far,the limit of user information transmission rate of direct current biased optical orthogonal frequen⁃cy division multiplexing access(DCO-OFDMA)for visible light communication(VLC)system with finite-alphabet inputs is yet unknown.In this paper,the user accurate achievable rate and its lower bound of the DCO-OFDMA system with fi⁃nite-alphabet inputs are derived,and the total electrical transmission power minimization problem under user rate thresh⁃old constraints is studied.Since the original optimization problem is a joint optimization problem of minimizing the total electrical transmission power with the optimization variables of subcarrier allocation,power allocation and DC-bias,which is with high complexity and difficult to solve,by deriving the optimal DC-bias and fixed subcarrier allocation,the original problem is simplified into a single variable optimization problem,which is,minimizing the total information transmission power with power allocation as the optimization variable.Moreover,by using the Lagrangian function and Karush-Kuhn-Tucker(KKT)conditions,we propose a power allocation scheme to minimize the total information trans⁃mission power with user rate threshold constraints.Numerical results show that the power allocation scheme proposed in this paper depends on the channel gain difference between subcarriers and the user rate threshold,and its performance is significantly better than the equal power allocation scheme at the low rate threshold and the high rate threshold,more⁃over,its performance is significantly better than the traditional water-filling power allocation scheme at the high rate threshold.

关 键 词：可见光通信 直流偏置光正交频分多址接入 有限字符输入 直流偏置 资源分配 

分 类 号：TN929[电子电信—通信与信息系统]