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1.
针对异构网络中D2D通信复用蜂窝用户频谱时存在的频谱分配问题,该文提出一种基于改进离散鸽群优化(PIO)算法的D2D通信资源分配机制。通过设置信干噪比(SINR)门限值来保证用户的通信服务质量(QoS),采用功率控制算法为用户设置发射功率,使用基于运动权值的二进制离散鸽群优化(MWBPIO)算法为D2D用户进行资源分配,并将D2D通信技术与中继技术进行有效结合,为边缘用户建立D2D中继链路,保证边缘用户的通信质量,最大化系统性能目标。仿真结果表明,该方案有效抑制了异构通信系统中引入D2D用户后导致的干扰问题,提高了边缘用户的通信质量和系统的频谱利用率以及系统的能效。  相似文献   

2.
Wireless Personal Communications - Device to device (D2D) communication is a candidate technology to ascertain the 5G wireless system. To implement the D2D communication in an in-band cellular...  相似文献   

3.
In this paper, we discuss four different optimization problems for distributed antenna systems (DAS) with and without D2D communication, respectively. The first and the third problems are maximizing spectral efficiency (SE) and energy efficiency (EE) of the DAS with D2D communication on the conditions of the minimum SE of DAS as well as D2D pair, the maximum transmit power of each remote access unit (RAU) and maximum transmit power of D2D transmitter. The second and the forth problems are maximizing SE of the DAS on the conditions of the minimum SE as well as the maximum transmit power of RAUs. We exploit the sub-gradient iteration method to obtain the optimal power allocation and summarize optimal power allocation algorithms for the first and second problems. We exploit fractional programming method to investigate the third and fourth problems and develop corresponding optimal power allocation algorithms. Simulation results demonstrate the effectiveness of the proposed power allocation algorithms and show the SE and EE of the DAS by using D2D communication are much better than DAS without D2D communication.  相似文献   

4.
The related D2D (device-to-device) and V2X (vehicle-to-everything) are regarded as vital components of 5G communication system,which providing alternative network services and multiple application services for cellular network.In the meanwhile,SDN (software defined networking) can improve the compatibilities and flexibilities of D2D and V2X.SD-D2D (software defined D2D communication) and SD-V2X (software defined V2X communication) technologies were reviewed.Based on their similarities and respective characteristics,their state-of-arts and architectures were reviewed accordingly,and the key technologies such as D2D location/discovery management,D2D routing control,D2D flow table management,V2V path scheduling,and V2V path recovery were analyzed.Finally,it was pointed out that the SD-D2D architecture was approaching mature and the SD-V2X framework had been preliminarily determined,the existing problems of interference management,mobile management and routing management in D2D/V2X communication could be effectively solved.Furthermore,it was also pointed out that the disconnection between the existing SD-D2D/V2X studies and the actual application needed to be overcome.  相似文献   

5.
Device-to-Device(D2D)通信是下一代(5G)移动网络的重要组成部分。D2D设备间在不依赖基站的情况下直接进行数据传输,并通过重复使用蜂窝小区的频率资源从而提高移动通信系统的容量。为了激励蜂窝网络用户参与到D2D通信,运营商对D2D通信的定价是一个很关键的问题。文中首先介绍了D2D的基本概念及其四种主要类型,并就其中DR-OC型D2D通信定价提出了运营商和D2D设备的收益模型,然后仿真分析了网络中谱单价和奖励带宽对双方收益的影响。仿真结果显示运营商可以通过调整奖励带宽来协调双方收益以激励更多的用户参与到D2D通信。  相似文献   

6.
Device-to-Device(D2D)是一种在LTE-A系统中通过重用小区内宏蜂窝用户的资源来实现端到端通信的新型技术。本文从实际应用的角度出发,首先对D2D技术的原理和应用进行了分析,然后讨论D2D技术应用于LTE-A系统中的优缺点,接着通过仿真验证了D2D技术在LTE-A系统中的优势。最后阐述了D2D技术在LTE-A系统中应用可研究的方向及技术展望。  相似文献   

7.
为了优化长期演进(LTE)系统引入设备直传(D2D)通信后带来的同频干扰、系统边缘用户性能恶化问题,提出一种基于信干噪比(SINR)的多小区D2D通信资源分配方案,通过调整信干噪比阈值将部分蜂窝用户(CU)转化为D2D用户并释放频谱资源进而获得较佳的资源分配策略,同时提出一种基于小区间D2D竞争机制的配置算法有效降低小区间干扰.仿真表明,算法能够有效提升系统容量,并提升小区边缘D2D用户公平性.  相似文献   

8.
刘艳君  郭爱煌 《通信技术》2015,48(7):814-817
D2D(Device-to-Device)通信作为蜂窝网的辅助通信方式,可以有效提高系统容量,具有提高频谱效率、减小时延等优势。模式选择是蜂窝网与D2D联合通信的关键问题之一。提出一种基于时延的D2D通信模式选择算法,该算法引入队列状态信息模型,以队列长度为权重的最大加权算法为调度策略,以时延作为模式选择的标准。通过仿真给出本算法与基于系统容量最大化的模式选择算法的性能比较,仿真结果表明与基于系统容量最大化的模式选择算法相比,本算法所需时延和丢包率均减小约20%。  相似文献   

9.
在超密集D2D通信中,目前的中继选择方案主要假定中继设备具有主动意愿参与数据转发,但部分理性中继设备出于自身考虑,可能会存在时延或拒绝转发的自私行为,进而影响用户体验效果.从中继设备自私行为角度出发,提出了D2D通信中自私中继设备识别方法,进而提出了基于自私行为分析的超密集D2D中继选择算法.首先,定义了联合兴趣度、转...  相似文献   

10.
In this paper,a new communication model is built named grouping D2D(GD2D).Different from the traditional D2D coordination,we proposed GD2D communication in licensed and unlicensed spectrum simultaneously.We formulate a resource allocation problem,which aims at maximizing the energy efficiency(EE)of the system while guaranteeing the quality-of-service(Qos)of users.To efficiently solve this problem,the non-convex optimization problem is first transformed into a convex optimization problem.By transforming the fractional-form problem into an equivalent subtractive-form problem,an iterative power allocation algorithm is proposed to maximize the system EE.Moreover,the optimal closedform power allocation expressions are derived by the Lagrangian approach.Simulation results show that our algorithm achieves higher EE performance than the traditional D2D communication scheme.  相似文献   

11.
An unmanned aerial vehicle (UAV)-assisted communication is a promising technique for enabling ground users in a non-functional area (NFA) or disaster area to communicate. All the base stations in the disaster area may be partially or fully damaged due to the natural calamity. Device-to-device (D2D) communication can be a viable solution for immediate connection between users in an NFA. We propose a UAV-assisted multi-hop D2D communication following a hybrid power-time switching (PTS) in this paper. Moreover, a D2D user of a cluster can communicate with another D2D user in a different cluster through UAVs. However, D2D users can harvest energy from their respective ad hoc energy stations and forward the information to the nearby D2D user following a hybrid PTS-based strategy. We propose a time frame for the same and show a node-based energy harvesting strategy. The expressions of outage probability, throughput, end-to-end energy consumption, and energy efficiency are developed for the Rician and Nakagami-m faded channel. The impact of several network parameters such as energy harvesting factor, energy harvesting efficiency, and fading parameter on the network performance is also indicated.  相似文献   

12.
5G通信技术中终端直通(D2D通信)的功率分配是近期研究的热点,为了提升系统容量和频谱利用率,将毫米波与D2D通信技术结合,在此技术中,针对28GHz频段上行链路及下行链路蜂窝网络中的D2D资源分配进行了研究,将其系统总吞吐量达到最大化算法进行优化。首先,推导出每个D2D对所对应的准入集,其次,在考虑每个D2D对用户以及蜂窝用户功率控制情况下,分别求出上行链路及下行链路中的吞吐量,最后,在保证D2D对总吞吐量最大化前提下将蜂窝用户信道分配给D2D对。仿真结果表明,所提出的方案可以提高系统的吞吐量。  相似文献   

13.
Xu  Yi-Han  Liu  Meng-Lian  Xie  Jing-Wei  Zhou  Jun 《Wireless Personal Communications》2021,120(4):2693-2710

The rapid growth of traffic demand and innovation of mobile networks have pushed the current communication infrastructure to provide a tight integration of different wireless technologies. On the one hand, all user connections are expected to be heterogeneous in future networks and thus an intelligent mobility management is essential to satisfy the requirements of lower latency, less power consumptions and last but not least possible uninterrupted ongoing session when a User Equipment (UE) moves across network boundaries. On the other hand, Device-to-Device (D2D) communication as a revolutionary technology to enhance network performance has shown a great potential in dominating future communication market. Consequently, in this paper, we investigate the mobility management problem for D2D communications in heterogeneous networks. We leverage on IEEE 802.21 Media Independent Service (MIS) and propose a new framework, so-called enhanced version of IEEE 802.21 MIS that supports D2D communication (E-MIS-D2D) to enhance D2D mobility experience over heterogeneous networks. The E-MIS-D2D is a network assisted and initiated architecture, in which a load-aware mode selection algorithm is also proposed for selecting the transmission mode between D2D and non-D2D modes. Through extensive simulations, we validate that the proposed method outperforms the existing methods in terms of packet loss ratio, average throughput, latency, bandwidth usage and load rate of eNB.

  相似文献   

14.
Underlay device-to-device (D2D) communication is an attractive technology enabling nearby cellular users to communicate with each other directly in order to increase data rate and spectral efficiency. The current cellular heterogeneous networks consist of macrocell base stations and small cell base stations with different transmit powers and coverage areas. Femtocell is the most popular small cell which is expected to be utilized in dense and ultra-dense scenarios in the future. Network coding in relay-assisted multi-hop communications improves achievable transmission rate and coverage of D2D communications. In this paper, two-hop random linear network coding network in cooperative D2D communication (RLNC-CDC) is considered. We propose to use femtocell base station (FBS) as a relay. We assume that the D2D pair and relay operate in the frequency band which is allocated to femtocell network. Therefore, there would be interference from the relay node and the D2D communication on the femtocell network users. To reduce the interference, the sum of transmit powers of the D2D pair and selected relay FBS should be minimized in a way that the highest transmission rate for the D2D pair is achieved. The constraints on the bounds of transmit powers of the D2D and relay node as well as the minimum required transmission rate for D2D communication are considered and the optimum solution is obtained. Simulation results indicate that the proposed RLNC-CDC achieves higher data rate and smaller outage probability than the direct D2D transmission.  相似文献   

15.
文凯  卢彦博  夏威  范文倩 《电视技术》2015,39(22):44-48
终端直通技术(D2D)是一种终端在基站控制下直接进行通信而不需要基站转发的新型通信技术。D2D引入LTE-A蜂窝系统虽然可以带来吞吐量和频谱效率的提升,但是也会带来很大的干扰。综合近些年来的研究成果,合理的资源调度算法成为降低干扰,提升系统性能的关键。首先,描述了D2D通信技术引入LTE-A蜂窝网络后的系统干扰模型。然后,从模式选择、资源分配和功率控制三个方面综述了目前国内外文献关于资源调度算法的研究成果。  相似文献   

16.
Device-to-device (D2D) multicast communication is a useful way to improve the communication efficiency of local services. This study considers a scenario of D2D multicast communication in software defined cellular network and investigates the frequency resource allocation problem. Firstly, we build the system model and formulate the optimization problem. Secondly, a hierarchical scheme to achieve a suboptimal solution is proposed. To select appropriate user equipments (UEs) as potential D2D transmitters (PDTs), a social aware PDT selection method is proposed. Then, a resource allocation algorithm considering users’ priorities is proposed. Furthermore, to study the resource allocation for general system that UEs without priorities, a non-priority considered allocation algorithm is proposed also. Numerical simulation results show that the proposed schemes are effective in improving the system utility and reducing the resource consuming for D2D communications.  相似文献   

17.
Wireless Networks - Device to device (D2D) communication that provides high data rate proximity based direct communication between users, along with simultaneous wireless information and power...  相似文献   

18.
石纯子  朱琦 《信号处理》2017,33(7):953-960
D2D(Device-to-Device)通信作为第五代移动通信(5G, 5-generation)的关键技术之一,因其高频谱效率、低能耗等优点受到广泛关注。为了更好地满足D2D用户的服务质量(quality of service, QoS)需求,本文引入用户满意度的概念,提出了一种基于QoS的分簇信道分配算法。该算法运用图论着色方法为D2D用户分配信道,可分为三个步骤:首先构建D2D用户间的干扰图,然后在保证蜂窝用户QoS需求的情况下建立D2D用户的可用颜色列表,最后为D2D用户分簇,位于同一簇内的用户可以共享信道。仿真结果表明,本文算法可以有效提高D2D用户的满意度和系统公平性。   相似文献   

19.
Wireless Personal Communications - Device to device (D2D) communication is one of the potentials to achieve the established standards for 5G. It represents a direct communication between two...  相似文献   

20.
Chief UE的作用是辅助实现D2D通信与蜂窝网络通信更好地无缝切换并且提高通信的质量。对Chief UE的概念进行了详细描述,并且对于其在切换中的作用进行了相应的阐述和论证:在传统D2D通信的基础上,定义了其中一个性质稳定良好的UE为Chief UE,进行D2D连接的内部管理和通信,并且在需要切换时,能够进行通行保持直到整个通信切换的完成和结束。将具有Chief UE的D2D切换同不具有Chief UE的D2D切换进行了相应的对比和论述,以更好地论证Chief UE存在的必要性。  相似文献   

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