QoS -Aware Spectrum Sharing for Multi-Channel Vehicular Network

We consider QoS -aware band sharing in cognitive wireless networks where secondary users are allowed to access the band owned by a primary network provider. The intrusion from secondary users to primary users is forced to be below the tolerable limit. Also, signal to intrusion plus noise ratio (SINR) of each secondary user is maintained higher than a required level for QoS cover. When network load is high, admission control needs to be performed to satisfy both QoS and intrusion constraint. We propose an admission control algorithm which is performed jointly with power manage such that QoS needs of all admitted secondary users are satisfied while keeping the intrusion to primary users below the passable limit. When all secondary users can be supported at minimum rates, we allow them to increase their spread rates and share the spectrum in a fair manner. We formulate the joint power/rate allocation with max-min equality principle as an optimization problem. We show how to change it into a convex optimization problem so that its globally most favourable solution can be obtained. Numerical grades show that the proposed admission control algorithm achieves performance very close to the optimal solution.