Cross Layer Design Approaches, Schemes and Optimization Methodologies for Cognitive Radio Networks: a Survey

Wireless technology has seen a tremendous advancement in recent times. Overnight new researches are made and fascinating outcomes are accomplished. But it’s never imperative that such a technological growth in wireless system has offered numerous challenges to the research community. For improvement in the performance of wireless networks ‘cross-layer designing’ was coined. Many issues arouse for cross layer design. The situation became even tougher with new paradigm ‘cognitive networks’. Since cognitive networks are limited in performance by challenges in spectrum sensing, sharing, mobility, end to end Qos etc, a cross-layer design is worth pursuing. In this paper, we present an insight to cross-layer design first. Secondly, we introduce some of the approaches proposed in the literature followed by a short overview on classical optimization methodologies for cross-layering. Finally, an extensive survey on different schemes for performance enhancement is performed taking several recent works in literature. Tabulation is made systematically for quick reference.