The heterogeneous network structure is a promising paradigm to improve the quality of service across the entire network. Nevertheless, such a structure is challenging due to the presence of multiple-tier secondary users (SUs). In this study, the authors investigated the effect of spectrum allocation in heterogeneous cognitive radio networks with a primary network and two-tier secondary networks, and proposed a two-tier spectrum trading strategy which includes two trading processes. In Process One, they model the spectrum trading as a monopoly market, where the primary spectrum owner (PO) acts as the monopolist and the first-tier secondary users (FSUs) act as the buyers. They design an optimal quality-price contract to maximise the utility of PO, and the FSUs will choose the spectrum with appropriate quality and price to enhance their satisfaction. In Process Two, spectrum trading is modelled as a multi-seller, multi-buyer market. The dynamic behaviour of second-tier SUs is studied using the theory of evolution game, while the competition among FSUs is analysed via a non-cooperative game where the Nash equilibrium is considered as the solution. The existences of the optimal contract, evolutionary equilibrium and Nash equilibrium are demonstrated in the performance evaluation.

中文翻译：

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异构认知无线电网络中频谱分配的两层交易策略设计

异构网络结构是提高整个网络服务质量的一种有希望的范例。但是，由于存在多层二级用户（SU），因此这种结构具有挑战性。在这项研究中，作者研究了频谱分配在具有主网络和两层辅助网络的异构认知无线电网络中的影响，并提出了包括两个交易过程的两层频谱交易策略。在过程一中，他们将频谱交易建模为垄断市场，其中主要频谱所有者（PO）充当垄断者，而第一层二级用户（FSU）充当买方。他们设计了一个最佳的质量价格合同，以最大程度地利用采购订单，FSU将选择具有适当质量和价格的频谱以提高满意度。在流程二中，频谱交易被建模为一个多卖方，多买方市场。使用演化博弈理论研究了第二层SU的动态行为，同时通过以纳什均衡为解决方案的非合作博弈分析了FSU之间的竞争。在绩效评价中证明了最优合同，演化均衡和纳什均衡的存在。