On Channel Hopping Sequences With Full Rendezvous Diversity for Cognitive Radio Networks

Abstract

In cognitive radio networks (CRNs), establishing a communication link between a pair of secondary users (SUs) requires them to rendezvous on a common channel which is not occupied by primary users (PUs). Under time-varying PU traffic, asynchronous sequence-based channel hopping (CH) with the maximal rendezvous diversity is a representative technique to guarantee an upper bounded time-torendezvous (TTR) for delay-sensitive services in CRNs, without requiring global clock synchronization.Maximum TTR (MTTR) and maximum conditional TTR (MCTTR) are two commonly considered metrics for evaluating such CH sequences, and minimizing these two metrics is the primary goal in the sequence design of various paper reported in the literature. In this paper, to investigate the fundamental limits of these two metrics, we first derive lower bounds on the MCTTR and MTTR, and then propose an asymmetric design which has the minimum MCTTR and an improvement on MTTR than other previously known algorithms. Moreover, when the number of licensed channels is odd, our proposed design achieves the minimum MTTR. We also present the TTR performance of the proposed design via simulation. DRAFT This paper continues the work to investigate asynchronous CH sequences with the maximal rendezvous diversity under this objective. The follow-on tasks after initial rendezvous, such as channel contention procedure and data packet transmission, are outside the scope of this paper.Obviously, MTTR and MCTTR provide upper bounds on the TTR for two extreme channel conditions, and hence have been commonly considered for those applications that have stringent worst-case TTR requirement. DRAFT

Efficient Matrix-Based Channel Hopping Schemes for Blind Rendezvous in Distributed Cognitive Radio Networks

“…Meanwhile, the sender plays the role of “child” which stays at the same channel for L time slots to be found by the receiver and then repeatedly hops to another unvisited channel. The FARCH [30] is another GC scheme which follows similar procedures as the WFM for generating its CH sequences when L is even. However, the FARCH receiver follows a different strategy when L is odd which enhances the TTR performance.…”

“…This section presents the performance evaluation of the developed QS-CH and IQSF-CH schemes as compared with some extant blind CH rendezvous schemes. The proposed QS-CH scheme is compared with six representative asymmetric-role schemes (four GC schemes, FDCH-RP [27], PCH [28], AAsync [31], and FARCH [30,34] as well as two LC schemes named as D-QCH in [32] and SJRW [23]). On the other side, the proposed IQSF-CH scheme is compared with six representative symmetric-role CH schemes (four GC schemes, EJS [20], T-CH [40], D-CH [40], and S-QCH in [32] as well as two LC schemes named as ZOS [44] and MTP [21,43]).…”

Multi-Radio Based Rendezvous Technique for Heterogeneous Cognitive Radio Sensor Network

“…Non-assisted rendezvous, on the other hand, is one that operates without the assistance of a central controller (or another node) and does not have a CCC. There are many approaches for non-assisted rendezvous techniques presented in the conventional references [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 ]. The general terminologies used for our articles related to rendezvous are summarized as follows: Channel Symmetricity : For the symmetric channel, the cognitive radio transmitter (CR-Tx) and cognitive radio receiver (CR-Rx) have the same available channels.…”

“…However, with the uncertainty of channel symmetry and time synchronization at either end of CR nodes, a universal algorithm is needed for further improvement. A deterministic succession-based rendezvous for a better outcome was analysed in [ 26 ] and they proposed a channel rendezvous with maximum diversity. Bian et al suggested an asynchronous channel-hopping scheme [ 27 ].…”