Routing Metrics in Cognitive Radio Networks

Routing in cognitive radio networks (CRN) should consider both the end-to-end performances and the interference to the primary systems. In this paper, we categorized routing metrics into three types and derived new metrics of each type. Firstly, by considering the primary usage pattern and maximum CR link hold-time, we derived three new metrics MET, RH and METRH to capture different end-to-end performances. We categorized these metrics as the first type. Then, interference caused by periodic sensing was introduced. We derived a novel metric LTP to reflect this interference and categorized this metric as the second type. Finally, by making trade-off between end- to-end performances and interference to the primary users, we proposed metrics METI, RHI and METRHI which belong to the third type of routing metric. Simulation results indicate our proposed metrics of the first two types can accurately capture the performances they attempt to reflect. And all the proposed metrics outperform the traditional Minimum Hop metric (MH) in the considering performances by a large margin.