飞蜂窝体系结构的发展

1 前言 飞蜂窝(Femtocell)又叫家庭基站,是安装在家庭中的微小基站,通过家庭固定宽带网络实现至移动运营商网络侧的回传.Femtocell技术能使运营商和终端用户双方受益.     

家庭基站成为移动通信新热点

目前移动通信业出现了一个新热点Femtocell.Femto的意思是飞秒(10-12秒),Femtocell就是超微蜂窝,可以称为家庭基站.从2G GSM、3G到WiMAX都在发展这种家庭基站.     

Picochip积极布局中国Femtocell市场为3G运营商寻找“蓝海”

什么是Femtocell:Femtocell(毫微微蜂窝式基站)又称桌面基站,是一种家庭基站技术,主要用来解决家庭室内覆盖的问题.但是由于它具有运行于IP协议、通过用户IP宽带网接人运营商的移动核心网和超小型化、即插即用等创新特性,呈现给运营商一片"蓝海".     

picoChip：所有基站都将如此而生

在此次Femtocell论坛上,picoChip公司的市场总监Andy Gothard做了题为＂总有一天,所有的基站都将如是而生＂,他指出,Femtocell的许多特性正被许多其它类型的基站所用,此前Femtocell由于在尺寸上的限制有很多严苛的要求,现在实现这些要求的很多技术可以被其它的基站所用。另外,他还带来了picoChip最新的可以应用于公共接入领域的芯片PC333。并接受了记者的采访。     

Fentocell加速3G全业务运营或蕴含无限商机

近日,2009年中国Femtocell家庭基站高峰论坛在北京召开.Femtocell技术以其自身的技术特点受到了国际运营商巨头和厂商的青睐,过去的一年里更是在全球范围内加大部署.记者了解到,Femtocell论坛已经拥有117名成员,其中包括17个世界排名前20位的运营商,构成了成熟Femlocell的生态系统.     

3G、Wi-Fi、LTE：Femtocell寻找新蓝海

Femtocell（毫微微蜂窝式基站）又称桌面基站,是一种家庭基站技术,主要用来解决家庭室内覆盖的问题。但是由于它具有运行于IP协议、通过用户IP宽带网接入运营商的移动核心网和超小型化、即插即用等创新特性,通过在住宅、企业或特定环境部署Femtocell可     

厂商动态

华为发布新一代Femtocell产品 华为近日正式发布了面向大众市场的新一代Femtocell商用产品。该产品采用华为自主研发的专用芯片,以及新平台和新设计。Femtocell是一种毫微微蜂窝基站,体积小巧,可作为移动网络的接入点,通过宽带为用户提供高质量的室内3G数据业务和语音业务。华为新一代Femtocell能够与华为第四代基站实现无缝切换,在高质量、高可靠性、高安全性、友好的用户界面、创新的造型设计等方面为业界树立了标杆,使家庭用户易于接受,运营商便于管理。     

Femtocell国际商用提速 运营商已形成差异化策略

截至目前,Femtocell基站全球部署量已超过220万,其中三分之一的商用部署是企业级的。进入2011年,Femtocell产业相比去年取得了巨大的成绩。今年Femto论坛宣布3G Femtocell数量已经超过了3G宏基站,目前已经有31个运营商在商用Femtocell,43个运营商承诺将会部署Femtocell。Femto不再局限于家庭从不久     

Femtocell网络中博弈式频率复用算法

提出了一种适用于Femtocell网络的博弈式频率复用算法。在Femtocell网络中,首先Femtocell基站通过感知其无线环境选择临时子频带,然后通过对分簇后的Femtocell网络执行簇内协调和簇间博弈两步算法,消除相邻Femtocell之间的频谱冲突,使Femtocell网络合理地复用频谱资源。在Femtocell随机部署的网络中,该方法解决了Femtocell网络中的频谱冲突问题。仿真表明,采用该算法后,Femtocell网络的频谱冲突得到有效改善,Femtocell系统平均信道容量明显提高。     

EPON技术在CDMA基站业务承载中的应用

从EPON承栽TDM业务的原理出发,结合CDMA基站业务承载的技术要求和现实需求,提出了通过EPON进行CDMA基站业务承载的方案,以解决CDMA基站业务承载、室内覆盖业务承载及今后Femtocell业务承载的需求.     

Interference Management with Block Diagonalization for Macro/Femto Coexisting Networks

A femtocell is a small cellular base station, typically designed for use in a home or small business. The random deployment of a femtocell has a critical effect on the performance of a macrocell network due to co‐channel interference. Utilizing the advantage of a multiple‐input multiple‐output system, each femto base station (FBS) is able to form a cluster and generates a precoding matrix, which is a modified version of conventional single‐cell block diagonalization, in a cooperative manner. Since interference from clustered‐FBSs located at the nearby macro user equipment (MUE) is the dominant interference contributor to the coexisting networks, each cluster generates a precoding matrix considering the effects of interference on nearby MUEs. Through simulation, we verify that the proposed algorithm shows better performance respective to both MUE and femto user equipment, in terms of capacity.     

毫微微小区技术浮出水面

毫微微小区是一种旨在改善室内覆盖的小型低成本基站，能够在网络最边缘提供高质量的覆盖，适用于家庭及办公室环境。与现有的微小区技术相比．毫微微小区具有设备单元小、网络效率高和成本低的优点。目前，毫微微小区技术仍处在初期阶段，在广泛商用之前还有许多技术、商用和监管方面的问题有待解决。但一旦该技术被用户广泛接受，实现规模商用。必将对移动产业产生不小的影响。     

Resource Allocation Based on Channel Sensing and Spatial Spectrum Reuse for Cognitive Femtocells

A cognitive femtocell is a new small cell based on a smart home base station to solve the spectrum-scarcity problem. Recently, dedicated resource allocation for cognitive femtocell to mitigate co-channel interference is extensively researched. However, the cognitive femtocell may suffer from the lack of frequency resource for its users due to high data traffic load of the macrocell. We propose a novel resource allocation and power control mechanism using spatial frequency reuse and spectrum sensing, which enables femto users in the cognitive femtocell to obtain more feasible resource. We analyze and evaluate the performance gain of the proposed scheme. Although data traffic load of the macrocell increases, the capacity of the cognitive femtocell can be maintained appropriately by the proposed resource allocation and power control scheme and it is shown that the performance is improved compared to that of the conventional scheme.

     

家庭基站中基于随机矩阵的能量动态检测频谱分配机制

针对家庭基站和宏基站并存的情况下会导致相互干扰以及协调使用频谱需要信令开销问题,提出了一种基于随机矩阵的频谱分配机制。该机制将动态的检测空闲频谱点的频谱感知技术应用于家庭基站和宏基站共存网络中,家庭基站在一个时间段内接收各个频点上的信号,利用随机矩阵能量动态检测频谱可用性,实时感知网络中的频谱空洞,生成可借用频谱点集合,选择业务请求用户服务质量高的家庭用户借用该集合。该方法以复杂度为代价,避免使用信令交互找到可用频谱,从而减少了网络信令开销。仿真结果表明所提机制能够提高网络容量和公平性以及网络链路效率。     

The applications of the femtocell in the mobile home networks

Femtocell (or femto in short) is the femtocell mobile base station launched in recent years based on the development trend of 3G technology and mobile broadbandization. It is also called home base station and is a base station product covered inside the user's house. The business modes and development of femto in StarHub, Vodefone and China Unicom are discussed in detail in this paper. In this article we overview the technical and business arguments for femtocells and compare it to other widely used network technologies.     

Robust uplink power control for co-channel two-tier femtocell networks

This paper is concerned with uplink interference suppression problem in two-tier femtocell networks through power control. Specifically, we consider the Quality-of-Service (QoS) of the macrocell user and femtocell users in terms of their received Signal to Interference-plus-Noise Ratios (SINRs) at macrocell base station (MBS) and femtocell base stations (FBSs), and we also take femtocell users’ power efficiency into consideration by designing an objective function, which is a weighted sum of transmission power and squared SINR difference between femtocell user's maximum SINR and actual SINR. Due to the error of the SINR at MBS caused by distance errors, a robust uplink power control problem is formulated, and it is equivalent to a robust convex optimization problem with femtocell users’ SINR constraints. Then, the robust convex optimization problem is converted into a general convex optimization problem. Moreover, a distributed power control algorithm combined with admission control is presented to obtain femtocell users’ optimal power allocation. Numerical results show the convergence and effectiveness of the proposed uplink power control algorithm.     

Statistics of macrocell-synchronous femtocell-asynchronous users? delays for improved femtocell uplink receiver design

In a typical macrocell network, the mobile users are synchronized to the macrocell base station (mBS), where users further away to the mBS transmit their signals earlier. In such a network, the signals of the macrocell users arrive at a femtocell base station (fBS) asynchronously, which may yield interference problems such as inter-carrier-interference in orthogonal frequency domain multiple access (OFDMA) systems. In this letter, statistics of the arrival times of macrocell-synchronous femtocell-asynchronous mobile users' signals to an fBS is derived (conditioned on the fBS-mBS distance), and its implications on the femtocell uplink receiver design are briefly discussed.     

异构携能通信网络中基于人工噪声辅助的鲁棒安全传输方案

异构携能通信网络中信道状态信息不准确时,为保证信息、能量传输的安全性与可靠性,该文提出一种基于人工噪声辅助的鲁棒安全传输方案。通过联合设计宏基站、微基站的下行信息波束及人工噪声矩阵,干扰窃听者,同时提升系统能量接收性能。在基站的发送功率约束、合法用户的信息接收及能量接收中断约束和窃听者的窃听信息中断约束下,以最大化系统能量接收性能为目标进行建模。针对该问题的非凸性,首先将其等效转化为一种易于处理的形式;而后进一步利用Berstein-type不等式处理其中的中断概率约束,将其转化为凸的问题进行求解。仿真结果验证了该方案的安全性和鲁棒性。     

毫微微蜂窝基站的自配置功率机制

为了解决分层网络中由于添加飞小区引起的一系列干扰问题,提出了一种飞小区基站的自配置功率机制。该机制首先分析了飞基站可能受到各种其他基站的干扰和引起对已有用户的干扰类型,然后设计了一个功率最优化问题,即在保证已有用户正常通信前提下最大化飞小区的系统容量,最后通过拉格朗日乘数法得到了功率自配置的最优解。仿真结果表明该机制对比于基于接收信号强度设置功率机制,有效降低了飞基站发射功率,提高了已有用户的吞吐量,减少了对已有用户的干扰。     

Power allocation and relay selection for network-coded D2D communication underlay heterogeneous cellular networks

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.