一种抑制小区间干扰的比例公平调度算法

针对LTE-Advanced系统中小区间干扰及用户公平性问题,提出了基于多小区联合预编码和静态功率控制的比例公平(MCPPC-PF)调度算法。通过干扰空间迫零和静态控制发射功率的方法抑制小区间干扰,并结合比例公平(PF)调度算法,提高用户的公平性。仿真结果表明,与传统算法相比,MCPPC-PF算法提升系统容量的同时还提高了用户的公平性;与基于多小区联合预编码和静态功率控制的最大化吞吐量调度算法相比,MCPPC-PF算法在系统容量损失了4.6%的情况下,边缘用户容量提高了约45%。     

LTE-A系统中比例公平调度算法的改进

在非连续载波聚合(高频+低频)场景下,载波衰减特性不同,聚合的载波有不同的覆盖范围,使得不同用户可调度的载波数量不同,若使用传统比例公平( PF)算法会导致小区不同位置用户资源配置的不公平性。本文提出了一种分组权重PF调度算法( GWPF ),根据用户可调度的载波数量,将用户和载波分组,并引入加权因子对原比例公平算法进行加权处理,从而提高用户公平性。仿真结果表明GWPF较PF算法有着更好的用户公平性和边缘小区吞吐量。     

最大化SLNR及软频率复用的比例公平调度算法

针对 LTE-Advanced 系统中小区间干扰及用户公平性问题,提出了最大化信漏噪比(SLNR)及软频率复用的比例公平调度算法(SLNR–SFR–PF)。该算法通过基于最大化 SLNR的分布式预编码和软频率复用的方法抑制小区间干扰,并结合比例公平调度算法,提高用户的公平性。仿真结果表明,与 SLNR–PF 算法相比,SLNR–SFR–PF 算法使系统容量提高了约7.9%,同时,小区边缘的平均用户数据速率提高了11.5%。     

LTE-Advanced载波聚合中的无线资源管理研究

载波聚合是LTE-Advanced系统的关键技术之一。文章中重点介绍了载波聚合中的移动性无线资源管理（RRM：Radio Resource Manage-ment）机制。在引入该机制的基础上,传统的正比公平（PF：proportional fair）调度算法并不能够很好地保证用户之间在资源分配方面的公平性,因此提出了Balanced PF（BPF）算法。从系统级仿真结果可以看出,与传统的PF算法相比,BPF算法可以提升边缘用户的吞吐量性能,改善用户之间的公平性。     

OFDM系统分组调度算法仿真与分析

对于蜂窝正交频分复用(OFMA)系统,分组调度技术是影响系统性能提升的重要因素。分组调度算法是为分组业务提供资源分配及复用的方法。这里介绍了分组调度技术原理及几种经典的调度算法,并通过Matlab仿真,对几种调度算法的公平性和吞吐量进行了比较。通过仿真可知,比例公平算法(PF,Proportional Fair)平衡考虑了系统吞吐量与公平性,取得了较好的效果。     

TD-LTE系统无线资源调度算法研究及性能分析

文章介绍了TD-LTE无线资源调度算法,包括轮询算法(Round Robin)、最大吞吐量算法(MaxTP)和比例公平算法(PF)等,并通过搭建的仿真平台仿真这几种算法的吞吐量及公平性,分析和比较各自的性能。     

基于干扰感知的上行调度算法研究

针对LTE系统中上行小区间干扰特性,提出了一种基于干扰感知的LTE上行比例公平调度算法改进方案。该方案通过小区协作方式计算协作簇内的小区调度优先级和基于干扰感知的用户调度优先级并以此进行资源调度。仿真结果表明,相对于未采用干扰感知的比例公平调度算法,该方案的两种形式都能够在保障系统吞吐量性能的前提下,有效地提高小区边缘用户性能,同时证明了干扰感知的越精确,小区边缘用户的性能越好。     

LTE-A系统多点协作传输技术研究

多点协作传输技术作为LTE-A中的关键技术,可显著提升小区边缘用户的速率和吞吐量。介绍了多点协作的原理,给出了相关系统模型,分析了多点协作的首要问题——协作节点的选择。针对多度协作会造成的系统性能下降,提出了适合的最大协作节点数。同时考虑到传统的PF调度算法会造成小区吞吐量下降,提出了适用于多点协作的归一化PF调度算法。最后,仿真两种调度算法在不同协作节点选择下的性能,通过比较平均小区吞吐量和边缘用户吞吐量说明归一化PF调度算法的优势。     

一种针对HSDPA中继系统的比例公平调度算法

由于系统在资源分配上的差异,现有的3GPP长期演进项目的后续演进(Long Term Evolution Advanced,LTE-A)中继系统中的调度算法并不能直接应用于高速下行链路分组接入(High Speed Downlink Packet Access,HSDPA)中继系统。提出了一种适合HSDPA中继系统的比例公平调度算法,并给出了算法流程。通过系统级仿真,比较了该算法与没有中继时的PF调度算法和两层比例公平(THPF)调度算法的性能。仿真结果表明,所提出的调度算法能够在提高用户吞吐率的同时更好地保证用户公平性要求。     

面向电网业务质量保障的5G高可靠低时延通信资源调度方法

该文研究面向电网业务质量保障的5G 高可靠低时延通信(URLLC)的资源调度机制,以高效利用低频段蜂窝通信系统内有限的频谱和功率资源来兼顾电力终端传输速率和调度时延、调度公平性,保障不同电力业务的通信质量（QoS）。首先,基于URLLC的高可靠低时延传输特性,建立电力终端多小区下行传输模型。然后,提出面向系统下行吞吐量最大化的资源分配问题模型并对其进行分步求解,分别提出基于定价机制与非合作博弈的功率分配算法和基于调度时延要求的改进比例公平算法（DPF）动态调度信道资源。仿真结果表明,提出的资源调度方法能在保证一定传输可靠性和公平性的条件下降低电力终端调度时延,满足不同业务等级的QoS需求,与已知算法对比有一定的优越性。     

A distributed pricing algorithm for achieving network‐wide proportional fairness

Proportional fairness (PF) scheduling achieves a balanced tradeoff between throughput and fairness and has attracted great attention recently. However, most previous work on PF only considers the single cell scenario. This paper focuses on the problem of achieving network‐wide PF in a generalized multiple base station multiple user network. The problem is formulated as a maximization model and solved using the dual method. By decomposing the dual objective function, we get a distributed pricing based algorithm. Optimality of this algorithm is presented. Although the algorithm is derived using fixed link rate assumption, it can still apply in the presence of time‐varying rates. The proposed algorithm is suitable for distributed systems in the sense that it does not need any inter base station communication at all. Simulations illustrate that the proposed distributed network‐wide PF scheduling algorithm achieves almost the same performance as the centralized one. Compared with traditional local PF (LPF) scheduling, the network‐wide PF scheduling achieves higher throughput, lower throughput oscillation, and greater fairness. Copyright © 2010 John Wiley & Sons, Ltd.     

Effective resource scheduling scheme considering scheduling relevancy for downlink joint transmission system

Coordinated multi-point(CoMP) transmission is a promising technique to improve both cell average and cell edge throughput for long term evolution-advanced(LTE-A).For CoMP joint transmission(CoMP-JT) in heterogeneous scenario,if joint transmission(JT) users are firstly scheduled,other non-JT users will not be allocated sufficient resources,i.e.,scheduling relevancy exists in the users under different cells in the same coordination cluster.However,the CoMP system throughput will decline remarkably,if the impact of scheduling relevancy is not considered.To address this issue,this paper proposes a novel scheduling scheme for CoMP in heterogeneous scenario.The principles of the proposed scheme include two aspects.Firstly,this scheme gives priority to user fairness,based on an extended proportional fairness(PF) scheduling algorithm.Secondly,the throughput of the coordination cluster should be maintained at a high level.By taking the non-CoMP system as a baseline,the proposed scheme is evaluated by comparing to random PF(RPF) and orthogonal PF(OPF) scheme.System-level simulation results indicate that,the proposed scheme can achieve considerable performance gain in both cell average and cell edge throughput.     

Multi-user Fair Scheduling in the Downlink of CDMA Packet Systems

A fair scheduling algorithm is proposed to improve the system throughput while maintaining the fairness in the downlink of a code-division multiple access (CDMA) system employing AMC and multicodes. R. Kwan and C. Leung suggested an optimal scheduling to maximize the total throughput based on simultaneous transmissions strategy. In this letter, we extend the optimal scheduling so that some degree of fairness can be maintained. We formulate a mixed-integer nonlinear programming problem to assign the radio resources such as the transmit power and codes to several users effectively. The result shows that the proposed algorithm provides a significant throughput gain over PF scheduling with one-by-one transmission at the same level of fairness     

基于QoS付费业务的LTE下行跨层分组调度算法

准4G网络（LTE）即将商用会给人们带来更多的方便,以至于大量用户在日常生活中使用更多的QoS业务,这样系统会出现了拥塞和调度不够合理的情况,影响了高优先级业务的丢包率、时延和公平性。通过对LTE下行跨层分组调度各种算法的研究分析,从时延、丢包率、吞吐量和公平性等因素入手,在原有的比例公平性调度算法（PF）上进行改进,加入了补偿因子和付费权重值,使得改进型跨层调度算法,在吞吐量有一定提高的情况下,有效地降低了高优先级业务的丢包率和时延,并确保了高优先级业务的公平性。     

Resource scheduling scheme with QoS support in two-hop relay-enhanced OFDMA systems

As the system performance is obviously improved by introducing the concept of relay into the traditional orthogonal frequency division multiple access(OFDMA)systems,resource scheduling in relay-enhanced OFDMA systems is worthy of being studied carefully.To solve the optimization problem of achieving the maximum throughput while satisfying the quality of service(QoS)and guaranteeing the fairness of users,a novel resource scheduling scheme with QoS support for the downlink of two-hop relay-enhanced OFDMA systems is proposed.The proposed scheme,which is considered both in the first time sub-slot between direct link users and relay stations,and the second time sub-slot among relay link users,takes QoS support into consideration,as well as the system throughput and the fairness for users.Simulation results show that the proposed scheme has good performance in maximizing system throughput and guaranteeing the performance in the service delay and the data loss rate.     

多用户多服务无线网络中感知用户体验的比例公平调度

The effective radio resource allocation algorithms, which satisfy diversiform requirements of mobile multimedia services in wireless cellular networks, have recently attracted more and more attention. This paper proposes a service-aware scheduling algorithm, in which the Mean Opinion Score (MOS) is chosen as the unified metric of the Quality of Experience (QoE). As the network needs to provide satisfactory services to all the users, the fairness of QoE should be considered. The Proportional Fair (PF) principle is adopted to achieve the trade-off between the network performance and user fairness. Then, an integer programming problem is formed and the QoE-aware PF scheduling principle is derived by solving the relaxed problem. Simulation results show that the proposed scheduling principle can perform better in terms of user fairness than the previous principle maximizing the sum of MOS. It also outperforms the max-min scheduling principle in terms of average MOS.     

Resource scheduling in downlink LTE-advanced system with carrier aggregation

In this paper,we focus on the resource scheduling in the downlink of long term evolution advanced (LTE-A) assuming equal power allocation among subcarriers.Considering the backward compatibility,the LT...     

Scheduling with base station diversity and fairness analysis for the downlink of CDMA cellular networks

Efficient packet scheduling in CDMA cellular networks is a challenging problem due to the time variant and stochastic nature of the channel fading process. Selection diversity is one of the most effective techniques utilizing random and independent variations of diverse channels to improve the performance of communication over fading channels. In this paper, we propose two packet scheduling schemes exploiting base station selection diversity in the downlink of CDMA cellular networks. The proposed schemes rely on the limited instantaneous channel state information (CSI) to select the best user from the best serving base station at each time slot. This technique increases the system throughput by increasing multiuser diversity gain and reducing the effective interference among adjacent base stations. Results of Monte Carlo simulations are given to demonstrate the improvement of system throughput using the proposed scheduling schemes. In addition, we investigate fairness issue of wireless scheduling schemes. Due to different characteristics of wireless scheduling schemes, the existing fairness indexes may result in misleading comparison among different schemes. We propose a new fairness index to compare the overall satisfaction of the network users for different scheduling schemes. Copyright © 2006 John Wiley & Sons, Ltd.