Over the last few years, we have seen dramatic increase in the demand for radio spectrum in the world due to rapid growth in wireless services and applications. In order to meet the growing demand for radio spectrum, new schemes should be developed for utilizing free spectrum effectively. Cognitive radio (CR) is promising technology that enables solving spectrum scarcity problem effectively. Thus, in this paper, we propose two schemes to motivate primary user (PU) to share spectrum with secondary users (SUs). The key concern of the proposed schemes is maximizing PU’s profit by hiring free spectrum to wealthy SUs. In the eviction scheme, SUs with less profit are expelled from service to serve wealthy SUs. The folding scheme reconfigures spectrum request to serve it. It reduces the size of request if the available size is not sufficient for the request. The simulation results demonstrate that the ability of new schemes to maximize PU’s profit. Apparently, the results confirm the ability of the proposed schemes to utilize the free spectrum efficiently.

在过去几年中，由于无线服务和应用的快速增长，我们看到全球对无线电频谱的需求急剧增加。为了满足对无线电频谱日益增长的需求，应开发新的方案以有效利用免费频谱。认知无线电（CR）是一种很有前途的技术，可以有效地解决频谱稀缺问题。因此，在本文中，我们提出了两种方案来激励主要用户（PU）与次要用户（SU）共享频谱。拟议计划的主要关注点是通过向富有的 SU 租用免费频谱来最大化 PU 的利润。在驱逐计划中，利润较少的 SU 会被驱逐出服务，以服务于富有的 SU。折叠方案重新配置频谱请求以服务它。如果可用大小不足以满足请求，它会减小请求的大小。仿真结果表明，新方案能够最大限度地提高 PU 的利润。显然，结果证实了所提出方案有效利用自由频谱的能力。