家庭基站：优化4G通信性能降低成本

目前，通信网络架构的发展已经接近香农理论中的极限值，依靠改变调制方式或提升技术来改善网络容量与速度的途径正在走向尽头，未来的解决方案只能依靠缩小基站的物理尺寸，以得到更广泛和更密集的覆盖范围。     

An adaptive step-size spectrum auction mechanism for two-tier heterogeneous networks

Recently, with the rapid growth of demands for wireless communications, dynamic spectrum allocation is one of the key technologies in cognitive radio networks to resolve the realistic problem of low utilization efficiency of spectrum. It mainly focuses on how the spectrum owner dynamically allocates idle spectrum to secondary users who have no licensed spectrum for communications. In this paper, a dynamic spectrum allocation model based on auction theory in a two-tier heterogeneous network is proposed, in which the primary users (PUs) are the sellers, the central processor (CP) auctioneer is the coordinator, and femtocell base station (FBS) as the buyer bids for the idle spectrum and act as a wireless access point that provides communication services for secondary users (SUs). Its basic process is as follows: the auctioneer gradually raises the spectrum price from the reserved price; each bidder decides whether participates in the purchase or not. It is characterized by distributed execution and low complexity which can reduce unnecessary information exchange between primary users or secondary users. Meanwhile it can enhance the utilization of spectrum and improve the efficiency of the auction by generate the incentive mechanism.     

EPON在CDMA基站业务承载中的应用

文章从EPON承载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.以满足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.经过实际验证,此应用效果良好,具有较高的实用和推广价值.     

Femto典型场景应用和业务策略探讨

Femtocell是业界针对全业务运营商提出的一种室内覆盖、容量解决方案,它利用已有固定宽带提供回程,实现移动通信网络的有效延伸。作为固定移动融合的新技术,个人移动通信市场和家庭宽带通信市场的结合点,Femtocell将是全业务运营商提供差异化业务的重要技术手段。本文主要介绍了Femtocell的技术方案以及国内外运营商的运营现状和策略,同时分析了基于Femtocell的典型场景应用和业务策略。     

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。     

家庭信息化“管”端支撑技术探讨

文章结合中国移动家庭信息化实施案例,重点对家庭网关及家庭无线宽带业务进行了探讨。首先,指出发展家庭网关对于电信运营商意义重大,并指出电信运营商发展电信级家庭网关业务的优势所在;其次,概述电信运营商在无线宽带覆盖中遇到的问题并提出具体解决方案,并通过实践证明WLAN Mesh组网结合CPE应用在小范围覆盖、低成本、快速布网方面具有一定优势;最后,对家庭信息化未来发展趋势进行了展望。     

Load-aware femtocell placement in the commercial buildings

Femtocells are designed to cover small indoor areas. In commercial buildings, femtocell placement and number is one of the most important network issues. In such buildings, another problem is uneven traffic distribution in different spaces, which causes high traffic and low traffic areas. Due to the small coverage areas of femtocells and these high traffic and low traffic areas, some femtocells are overloaded and some femtocells are underloaded. Also, increase in the distance of high-traffic areas from the femtocells, increases the number of resource blocks used. These issues reduce network efficiency. In this article, femtocell placement has been managed in such a way that the traffic load on the femtocells is balanced and is reduced the number of resource blocks used in the building and efficiency is increased. A mathematical model for femtocell placement has been introduced which balancing the femtocell load and reducing the average number of resource blocks used, the conditions of maximum coverage area and minimum femtocell number should also be fulfilled. This challenge has been addressed by using non-dominated sorting genetic algorithm (NSGA-II). An initial population generation algorithm and a selection function are also presented. The assessment results indicate that compared to the latest studies, this newly proposed method reduces the average load on the whole building by 79% and decreases the load variance between the femtocells by 86%.