Skolem Sequence Based Self-adaptive Broadcast Protocol in Cognitive Radio Networks

TL;DR

This paper introduces SASS, a novel broadcast protocol for cognitive radio networks that uses Self-Adaptive Skolem sequences to enable multi-channel broadcasting and clock synchronization without information exchange.

Contribution

It presents a new channel hopping-based broadcast protocol utilizing Self-Adaptive Skolem sequences for robust multi-channel communication and clock synchronization in cognitive radio networks.

Findings

Successful broadcast over multiple channels demonstrated

Clock synchronization achieved without information exchange

Protocol adapts to any clock drift

Abstract

The base station (BS) in a multi-channel cognitive radio (CR) network has to broadcast to secondary (or unlicensed) receivers/users on more than one broadcast channels via channel hopping (CH), because a single broadcast channel can be reclaimed by the primary (or licensed) user, leading to broadcast failures. Meanwhile, a secondary receiver needs to synchronize its clock with the BS's clock to avoid broadcast failures caused by the possible clock drift between the CH sequences of the secondary receiver and the BS. In this paper, we propose a CH-based broadcast protocol called SASS, which enables a BS to successfully broadcast to secondary receivers over multiple broadcast channels via channel hopping. Specifically, the CH sequences are constructed on basis of a mathematical construct---the Self-Adaptive Skolem sequence. Moreover, each secondary receiver under SASS is able to adaptively synchronize its clock with that of the BS without any information exchanges, regardless of any amount of clock drift.