In cluster-based cooperative cognitive radio networks (CCRNs), spectrum sensing and decision making processes to determine whether the primary user (PU) signal is present or absent in the network are very important and vital issues to the utilisation of the idle spectrum. The reporting time delay is a very important matter to make quick and effective global decisions for the fusion center (FC) in a cluster-based CCRNs. In this paper, we propose the concept of multiple reporting channels (MRC) for cluster-based CCRNs to better utilize the reporting time slot by extending the sensing time of secondary users (SUs). A multiple reporting channels concept is proposed based on frequency division multiple access to enhance the spectrum sensing performance and reduce the reporting time delay of all cluster heads (CHs). In this approach, we assign an individual reporting channel to each cluster for reporting purposes. All the SUs in each cluster sequentially pass their sensing results to the corresponding cluster head (CH) via the assigned single reporting channel, which extends the sensing time duration of SUs. Each CH uses the dedicated reporting channel to forward the cluster decision to the FC that makes a final decision by using the “K-out-of-N” rule to identify the presence of the PU signal. This approach significantly enhances the sensing time for all SUs than the non-sequential as well as minimize the reporting time delay of all CHs than sequential single channel reporting approach. These two features of our proposed approach increase the decision accuracy of the FC more than the conventional approach. Simulation results prove that our proposed approach significantly enhances the sensing accuracy and mitigate the reporting time delay of CH compared to the conventional approach.

在基于群集的协作认知无线电网络（CCRN）中，频谱感应和决策过程（用于确定网络中是否存在主要用户（PU）信号）对于利用空闲频谱非常重要且至关重要。对于基于群集的CCRN中的融合中心（FC）做出快速有效的全球决策，报告时间延迟是非常重要的事情。在本文中，我们提出了基于群集的CCRN的多个报告通道（MRC）的概念，以通过延长辅助用户（SU）的感知时间更好地利用报告时隙。提出了一种基于频分多址的多报告通道概念，以增强频谱感测性能并减少所有簇头（CH）的报告时间延迟。用这种方法 我们为每个群集分配一个单独的报告渠道以进行报告。每个群集中的所有SU均通过分配的单个报告通道将其感测结果依次传递到相应的群集头（CH），从而延长了SU的感测时间。每个CH使用专用报告信道将群集决策转发到FC，FC通过使用“ N出N”规则来识别PU信号的存在来做出最终决策。与顺序单通道报告方法相比，此方法比非顺序方法显着增加了所有SU的感测时间，并使所有CH的报告时间延迟最小。与传统方法相比，我们提出的方法的这两个特征可提高FC的决策准确性。