【作者】 刘洋；

【导师】 孙彦景；

【作者基本信息】 中国矿业大学 ， 信息与通信工程， 2021， 硕士

【摘要】 近年来,随着移动通信技术的快速发展,人类社会对于数据传输的需求急剧增长,新的业务场景不断涌现,智能化的办公、学习、生活方式让当前的无线通信系统面临着巨大的挑战。为了应对未来通信系统中的海量设备连接与多样化应用场景,新型多址接入技术已成为通信领域的研究热点问题。其中,作为一种有潜力的新型多址技术,非正交多址接入技术(Non-Orthogonal Multiple Access,NOMA)凭借其可以显著提高系统的频谱利用率、系统吞吐量以及能量效率的优势,获得了众多国内外学者的密切关注。同时,NOMA与多输入多输出技术(Multiple-Input Multiple-Output,MIMO)的结合可以进一步提升系统性能,因此,本文以MIMO NOMA系统作为研究对象,分别从系统的可靠性和有效性角度对系统的性能进行研究。针对脉冲噪声背景下的MIMO NOMA系统,本文在系统发射功率受限以及用户信号传输速率要求约束条件下,构建了系统和速率最大化问题。由于所形成的优化问题是非凸的,无法直接进行求解,为了解决该问题,本文分别提出D.C.(Difference of Two Convex Functions,D.C.)算法和FP(Fractional Programming,FP)算法两种方案对优化问题进行转化。其中,D.C.算法利用一阶泰勒展开式近似代替目标函数,将其转化为D.C.形式;而FP算法采用二次变换的方式,对分式形式的目标函数的分子分母进行解耦,转化为特定形式,采用上述两种算法均可以得到原问题的最优解。仿真结果表明,本文所提出的两种算法均可以有效提高MIMO NOMA系统的和速率性能。针对通信场景中的脉冲噪声,本文主要研究了时域的脉冲噪声消除算法。以系统的输出信噪比及误码率性能作为评估目标,在经典的混合时域非线性预处理方法的基础上,提出了改进的脉冲噪声消除算法,对指标的计算过程进行了详细的数学推导,并将所提方案与其他方案进行了比较分析。最后,仿真结果表明,本文所提出的改进的脉冲噪声消除算法,在一定程度上可以有效改善系统的输出信噪比及误码率性能。该论文有图23幅,表5个,文献80篇。更多还原

【Abstract】 In recent years,with the rapid development of mobile communication technology,the demand for data transmission in human society has increased dramatically,and new business scenarios have continued to emerge.Intelligent modes of office,study and lifestyle make the current wireless communication system face huge challenges.In order to cope with the massive device connections and diversified application scenarios in the future communication system,the new multiple access technology has become a research hotspot in the communication field.Among them,as a potential new technology,non-orthogonal multiple access technology(NOMA)has attracted widespread concern from domestic and foreign scholars,on account of its advantages in significantly improving the spectrum efficiency,system capacity and energy efficiency of the system.In the meanwhile,the combination of NOMA and multipleinput multiple-output technology(MIMO)can further improve system performance.Therefore,taking the MIMO NOMA system as the research object,the paper studies the performance of the system from the perspective of system reliability and effectiveness.Under the background of impulsive noise,aiming at the MIMO NOMA system,this paper constructs system sum-rate maximization problem with the conditions of system transmission power limitation and users’ rates constraints.Since the formed optimization problem is non-convex,it cannot be solved directly.In order to solve this problem,two schemes are proposed,using the difference of two convex functions(D.C.)algorithm and Fractional Programming(FP)algorithm to transform the optimization problem respectively.The D.C.algorithm uses the first-order Taylor expansion to approximately replace the objective function,and transform it into the D.C.form.And the FP algorithm uses a quadratic transformation method to decouple the numerator and denominator of the objective function in fractional form,and transform it into a specific form.Thus,both algorithms can obtain the optimal solution to the original problem.From the simulation results,it can be seen that the two proposed algorithms can dramatically improve the sum-rate performance of the MIMO NOMA system.Regarding to the impulsive noise in the communication scene,the impulsive noise mitigation algorithms in the time domain are mainly studied.Taking the output signalto-noise ratio and bit error rate performance of the system as the evaluation targets,an improved impulsive noise mitigation algorithm is proposed,which is based on the classic hybrid time-domain nonlinear preprocessing method.A detailed mathematical derivation of the calculation process of the index is carried out,and the proposed scheme is compared and analyzed with other schemes.At last,the simulation results show that the proposed improved impulsive noise mitigation algorithm can effectively improve the output signal-to-noise ratio and bit error rate performance of the system to a certain extent.This thesis contains 23 figures,5 tables and 80 references.更多还原