Wireless and Photonic Networks Research Centre of Excellence (WiPNEt), Department of Computer and Communication Systems Engineering, University Putra Malaysia, Serdang 43400, Selangor, Malaysia.
Faculty of Computer Science and Information Systems, Thamar University, Dhamar 87246, Yemen.
Sensors (Basel). 2018 Dec 10;18(12):4360. doi: 10.3390/s18124360.
Channel rendezvous is an initial and important process for establishing communications between secondary users (SUs) in distributed cognitive radio networks. Due to the drawbacks of the common control channel (CCC) based rendezvous approach, channel hopping (CH) has attracted a lot of research interests for achieving blind rendezvous. To ensure rendezvous within a finite time, most of the existing CH-based rendezvous schemes generate their CH sequences based on the whole global channel set in the network. However, due to the spatial and temporal variations in channel availabilities as well as the limitation of SUs sensing capabilities, the local available channel set (ACS) for each SU is usually a small subset of the global set. Therefore, following these global-based generated CH sequences can result in extensively long time-to-rendezvous (TTR) especially when the number of unavailable channels is large. In this paper, we propose two matrix-based CH rendezvous schemes in which the CH sequences are generated based on the ACSs only. We prove the guaranteed and full diversity rendezvous of the proposed schemes by deriving the theoretical upper bounds of their maximum TTRs. Furthermore, extensive simulation comparisons with other existing works are conducted which illustrate the superior performance of our schemes in terms of the TTR metrics.
信道汇聚是分布式认知无线电网络中实现次级用户(SU)之间通信的初始和重要过程。由于基于公共控制信道(CCC)的汇聚方法存在缺点,信道跳频(CH)已吸引了大量用于实现盲汇聚的研究兴趣。为了确保在有限的时间内完成汇聚,大多数现有的基于 CH 的汇聚方案基于网络中的整个全局信道集来生成其 CH 序列。然而,由于信道可用性的空间和时间变化以及 SU 感知能力的限制,每个 SU 的本地可用信道集(ACS)通常是全局集的一个小子集。因此,遵循这些基于全局生成的 CH 序列可能会导致汇聚时间(TTR)非常长,尤其是当不可用信道的数量较大时。在本文中,我们提出了两种基于矩阵的 CH 汇聚方案,其中 CH 序列仅基于 ACS 生成。我们通过推导它们最大 TTR 的理论上限来证明所提出方案的可靠和全分集汇聚。此外,还与其他现有工作进行了广泛的仿真比较,说明了我们的方案在 TTR 指标方面的优越性能。