A new communication framework for wide-band cognitive radio networks

IEEE Trans. Veh. Technol.

et al. 2016

Abstract-Channel rendezvous is a vital step to form a cognitive radio network (CRN). It is intractable to guarantee rendezvous for secondary users (SUs) within a short finite time in asynchronous, heterogeneous, and anonymous CRNs. However, most previous heterogeneous algorithms rely on explicit SUs' identifiers (IDs) to guide rendezvous, which is not fully distributed. In this paper, we exploit the mathematical construction of sunflower sets to develop a single-radio sunflower set (SSS)-based pairwise rendezvous algorithm. We propose an approximation algorithm to construct disjoint sunflower sets. Then, the SSS leverages the variant permutations of elements in sunflower sets to adjust the order of accessing channels instead of SUs' IDs, which is more favorable for anonymous SUs in distributed environments. We also propose a multiradio-sunflower-set-based pairwise rendezvous algorithm to bring additional rendezvous diversity and accelerate the rendezvous process. Moreover, for the case with more than two SUs, we propose a multiuser collaborative scheme in which SUs cooperatively exchange and update their channel-hopping sequences until rendezvous. We derive the theoretical upper and lower bounds of rendezvous latency of the proposed algorithms. Extensive simulation comparisons with the state-of-the-art blind-rendezvous algorithms are conducted, incorporating the metrics of maximum and expected time-to-rendezvous. The simulation results show that our algorithms can achieve rendezvous faster than previous works.

Section: Introductionmentioning

confidence: 99%

Fully Distributed Channel-Hopping Algorithms for Rendezvous Setup in Cognitive Multiradio Networks

IEEE Trans. Veh. Technol.

et al. 2016

“…(iv) Onymous/anonymous information. Onymous algorithms (e.g., Sym-ACH [8] and Framework in [9]) rely on distinct SUs' IDs to distinguish their CH sequences and guarantee rendezvous. However, SUs are usually anonymous with no explicit IDs in distributed CRNs.…”

Section: Introductionmentioning

confidence: 99%

A time-efficient rendezvous algorithm with a full rendezvous degree for heterogeneous cognitive radio networks

IEEE INFOCOM 2016 - The 35th Annual IEEE International Conference on Computer Communications

2016

Channel rendezvous is a prerequisite for secondary users (SUs) to set up communications in cognitive radio networks (CRNs). It is expected that the rendezvous can be achieved within a short finite time for delay-sensitive applications and over all available channels to increase the robustness to unstable channels. Some existing works suffer from a small number of rendezvous channels and can only guarantee rendezvous under the undesired requirements such as synchronous clock, homogeneous available channels, predetermined roles and explicit SUs' identifiers (IDs). In this paper, to address these limitations, we employ the notion of Disjoint Set Cover (DSC) and propose a DSC-based Rendezvous (DSCR) algorithm. We first present an approximation algorithm to construct one DSC. The variant permutations of elements in the ingeniously constructed DSC are then utilized to regulate the order of accessing channels, enabling SUs to rendezvous on all available channels within a short duration. We derive the theoretical maximum and expected rendezvous latency and prove the full rendezvous degree of the DSCR algorithm. Extensive simulations show that the DSCR algorithm can significantly reduce the rendezvous latency compared to existing algorithms.

“…(ii) Symmetric/asymmetric role. Asymmetric-role algorithms (e.g., Asym-ACH [6], Framework in [7]) need to pre-assign the role (either a sender or a receiver) before hopping. Different roles generate CH sequences based on different rules.…”

Section: Introductionmentioning

confidence: 99%

“…(iii) Onymous/anonymous information. Onymous algorithms (e.g., Sym-ACH [6], Framework in [7]) rely on distinct SUs' IDs to generate CH sequences. However, SUs in the distributed CRN are anonymous in most cases and they do not possess a public ID.…”

Section: Introductionmentioning

confidence: 99%

Padded-Dyck-Path-Based Rendezvous Algorithms for Heterogeneous Cognitive Radio Networks

2015 24th International Conference on Computer Communication and Networks (ICCCN)

2015

Rendezvous is a vital step for secondary users who want to initiate a communication in cognitive radio networks. In this paper, we propose a novel Padded-Dyck-Path-based (PDP) rendezvous algorithm that generates channel hopping sequences utilizing global channels. PDP is designed according to the roundabout Dyck path so as to increase rendezvous opportunities. As the global channels may not be shared in distributed environments, we also propose a local PDP (L-PDP) heterogeneous rendezvous algorithm that generates channel hopping sequences utilizing only local available channels. L-PDP can significantly reduce rendezvous latency and allow for distributed implementations. We prove that both PDP and L-PDP can provide guaranteed rendezvous and derive their upper bounds of rendezvous latency. Analytical and simulation results show that PDP and L-PDP outperform existing algorithms in terms of time-to-rendezvous in global and local scenarios, respectively.Index Terms-Cognitive radio networks, channel rendezvous, heterogeneous networks, Dyck path.