Cognitive radio (CR) is a hopeful technology to sort out spectrum scarcity and underutilization problem in ad hoc networks. With the help of cognitive radio technology, unlicensed users can efficiently utilize the unused part of heterogeneous licensed spectrum. In this article, we present a three-dimensional (3D) Markov chain analysis for spectrum management scheme under heterogeneous licensed bands of two different licensed spectrum pools in cognitive radio ad hoc networks. We present the concept of interpool and intrapool spectrum handoff in the proposed model and derive blocking probability, dropping probability, non-completion probability, and throughput to estimate the performance of the secondary users under heterogeneous licensed spectrum environment. The impact of secondary users dynamic along with the primary users’ activity model on the performance measuring metrics in terms of blocking probability, dropping probability, non-completion probability, and throughput for three different cases is also investigated. The proposed model offers significant improvement in the performance of secondary users under heterogeneous licensed spectrum environment in a CR ad hoc network.

中文翻译：

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认知无线电自组织网络中异构许可频谱环境下二级用户的性能分析

认知无线电（CR）是一种有希望的技术，可以解决ad hoc网络中的频谱稀缺和利用率不足问题。借助认知无线电技术，未经许可的用户可以有效利用异构许可频谱的未使用部分。在本文中，我们介绍了认知无线电自组织网络中两个不同许可频谱池的异构许可频带下频谱管理方案的三维（3D）马尔可夫链分析。在提出的模型中，我们提出了池间和池内频谱切换的概念，并推导了阻塞概率，丢包概率，非完成概率和吞吐量，以估计异构许可频谱环境下辅助用户的性能。还研究了二级用户动态以及一级用户的活动模型在三种不同情况下的阻塞概率，掉落概率，非完成概率和吞吐量方面对性能度量指标的影响。所提出的模型在CR ad hoc网络中异构许可频谱环境下，辅助用户的性能有了显着提高。