[论文解读] Handover between Macrocell and Femtocell for UMTS based Networks

Mostafa Zaman Chowdhury, Won Ryu+2 more|arXiv (Cornell University)|Oct 5, 2018

Advanced MIMO Systems Optimization参考文献 4被引用 88

一句话总结

本文针对UMTS宏小区–femtocell网络的切换优化，介绍了架构、信号流变化，以及一个用于减少不必要切换的方案，并进行了仿真验证。

ABSTRACT

The femtocell networks that use home base station and existing xDSL or other cable line as backhaul connectivity can fulfill the upcoming demand of high data rate for wireless communication system as well as can extend the coverage area. Hence the modified handover procedure for existing networks is needed to support the macrocell/femtocell integrated network. Some modifications of existing network and protocol architecture for the integration of femtocell networks with the existing UMTS based macrocell networks are essential. These modifications change the signal flow for handover procedures due to different 2-tier cell (macrocell and femtocell) environment. The measurement of signal-to-interference ratio parameter should be considered for handover between macrocell and femtocell. A frequent and unnecessary handover is another problem for hierarchical network environment that must be optimized to improve the performance of macrocell/femtocell integrated network. In this paper, firstly we propose the concentrator based and without concentrator based femtocell network architecture. Then we present the signal flow with appropriate parameters for the handover between 3GPP UMTS based macrocell and femtocell networks. A scheme for unnecessary handoff minimization is also presented in this paper. We simulate the proposed handover optimization scheme to validate the performance.

研究动机与目标

• 通过Femtocell在UMTS网络中满足对更高数据速率和更广覆盖的日益增长的需求。
• 通过架构修改将Femtocell回传链路与UMTS宏小区网络整合。
• 为两层结构的宏小区/室内型小区环境重新配置切换过程。
• 减少不必要/漏切换，以提升整体网络性能。

提出的方法

• 提出基于集中器和非集中器的Femtocell网络架构。
• 描述3GPP UMTS宏小区与Femtocell网络之间的切换信号流。
• 确定并将信噪比（SIR）作为关键的切换参数纳入。
• 提出一个在分层网络中减少不必要切换的方案。
• 提供对所提切换优化方案的基于仿真的验证。

实验结果

研究问题

• RQ1 应如何修改切换过程以支持两层宏小区–Femtocell的UMTS网络？
• RQ2 在该架构中，哪些信号流参数，尤其是SIR，影响切换决策？
• RQ3 优化方案能否在不降低性能的前提下有效减少不必要的切换？
• RQ4 哪些架构选择（基于集中器 vs 非集中器）会影响切换性能？
• RQ5 仿真是否验证了所提切换方案在提升网络性能方面的有效性？

主要发现

• 修改后的切换过程改变了宏小区–Femtocell环境中的信号流。
• 与SIR相关的测量对于可靠的宏小区到Femtocell切换至关重要。
• 提出了一个减少不必要切换的方案，以缓解分层网络中的过度切换。
• 对基于集中器的和非集中器架构在切换性能上的影响进行了分析。
• 仿真结果验证了所提切换优化方法的有效性。