Distributed Delay-Aware Routing and Metrics Evaluation for Cognitive Radio Networks
Cognitive radii can dynamically sense, negotiate, and switch to available spectral bands to enhance spectrum utilization. The available spectral resource may vary with time and places, which lead to several implementation difficulties to send data in multi-hop cognitive radio networks (CRNs). We considered such factors as available time, spectral bands, transmission ranges, error rates, and primary user interruption rates, as well as sensing, negotiating, selecting, and switching time, and designed a delay-aware routing metric for multi-band, multi-rate, and multi-range CRNs. A distributed routing scheme was designed, and the performance was evaluated by a centralized algorithm in regard to the average and maximal end-to-end delays. The results demonstrated that the metrics considering the link- and nodal-delays outperforms current solutions, including probability-aware, capacity-aware, and hop-count methods, by an average of 13%. We further discuss related issues and conclude our findings.
delay-aware routing performance end-to-end delay cognitive radius spectrum resource