Regulatory bodies recognize the possibility of an unlicensed and dynamic access to the TV-white spaces. As a consequence, it is expected that heterogeneous and independently operated networks will be interested in sharing the same bandwidth within the same service area. Along this direction, this article addresses the coexistence among multiple heterogeneous secondary networks (SNs) operating in the TV-white spaces by proposing a weighted autocorrelation-based spectrum sensing technique. This is designed for orthogonal frequency division multiplexing signals and is based on an efficient exploitation of the correlation properties of the received signal induced either by the cyclic prefix and by the potential oversampling at the receiver. In particular, the proposed approach enables the identification of concurrent SNs, belonging to a predefined set, suitably selecting the optimal autocorrelation weights. Furthermore, it is shown that the proposed scheme can operate in a blind mode to detect a potential unknown SN. A theoretical analysis is proposed in order to derive the false alarm probability of the proposed detector to prove that this is a Constant False Alarm Detector. Finally, performance comparisons with alternative schemes, by resorting to computer simulations, are presented to highlight the advantages of the proposed solution.

中文翻译：

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具有过采样和最优权重选择的基于相关的频谱感知，用于 TVWS 中基于 OFDM 的网络共存

监管机构认识到未经许可和动态访问电视空白空间的可能性。因此，预计异构和独立运营的网络将有兴趣在同一服务区域内共享相同的带宽。沿着这个方向，本文通过提出一种基于加权自相关的频谱感知技术，解决了在 TV-white 空间中运行的多个异构二级网络 (SN) 之间的共存问题。这是为正交频分复用信号设计的，并且基于对接收信号的相关特性的有效利用，这些相关特性由循环前缀和接收器处的潜在过采样引起。特别是，所提出的方法能够识别属于预定义集合的并发 SN，适当地选择最佳自相关权重。此外，表明所提出的方案可以在盲模式下运行以检测潜在的未知 SN。提出了一种理论分析，以推导出所提出的检测器的虚警概率，以证明这是一个恒定虚警检测器。最后，通过计算机模拟与替代方案的性能比较，以突出所提出的解决方案的优点。