CMORC: Class-based Multipath On-demand Routing protocol for Cognitive radio networks

Cognitive radio (cr) technology enables dynamic spectrum access (dsa) to improve the efficiency of under-utilized licensed bands and overcrowded unlicensed bands. however, providing an acceptable service for cognitive users requires more sophisticated approaches due to the existence of primary users (pu) with high priority over licensed bands. additionally, it is of paramount importance that interference with pus be reduced so that they can communicate without interruption. in order to meet requirements of users as much as possible and reduce interference with pus, a new class-based multi-path ondemand routing protocol for cognitive radio networks (cmorc) is proposed. cmorc is a multipath routing protocol, which defines two classes of routing to make delay or interference optimum. to the best of our knowledge, it is the first multipath protocol that takes into consideration both route discovery and rate allocation. cmorc finds the optimum sending rates for each path by solving an optimization problem for each routing class. since solving these optimization problems is shown to be easy, cmorc is an efficient and practical solution for radio equipment with limited hardware. the simulation results reveal that cmorc outperforms the other recent multipath routing protocol, d^2carp, in terms of interference, delay and packet delivery ratio depending on class type.