In this paper, we analyze vertical handovers in heterogeneous networks. Vertical handovers are an important ramification of user mobility in a heterogeneous wireless network since they directly impact network performance, such as throughput, packet delay, or call blocking probability. However, the study of vertical handovers faces many difficulties when it comes to analysis, including network modeling which is extremely complicated due to topology diversity. To tackle such analytic challenges, we propose a stochastic geometric analysis scheme on user mobility and small cell networks, in order to capture the impacts of different topologies. We derive a theoretical expression for the expected number of handovers that occur and a corresponding approximation. Our analysis shows that the number of vertical handovers is determined as a concave function of small cell radius $r$ when given the small cell density. Via simulations our analysis is verified in various wireless environments.

中文翻译：

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异构网络中随机部署小小区的垂直切换分析

在本文中，我们分析了异构网络中的垂直切换。垂直切换是异构无线网络中用户移动性的一个重要分支，因为它们直接影响网络性能，例如吞吐量、数据包延迟或呼叫阻塞概率。然而，垂直切换的研究在分析方面面临许多困难，包括由于拓扑多样性而极其复杂的网络建模。为了应对此类分析挑战，我们提出了一种关于用户移动性和小型蜂窝网络的随机几何分析方案，以捕捉不同拓扑的影响。我们推导出发生的预期切换次数的理论表达式和相应的近似值。我们的分析表明，当给定小小区密度时，垂直切换的数量被确定为小小区半径 $r$ 的凹函数。通过模拟，我们的分析在各种无线环境中得到验证。