In this paper, we propose new network simulator architecture to simulate the performance of multi-channel multi-radio mesh network in the NS-2. We add Multi-radio abstraction layer to manage multiple radio instances, and we are able to simulate regardless of the number of channels and radios in each node. Most of all, we implement some important procedures for realistic multi-channel multi-radio experiments such as channel switching mechanism and multiple radio usage policy. Using this architecture, we evaluate the performance when all of nodes utilize 3 radios according to the number of available channels. Simulation results show that the performance can be improved up to 2.15 times compared to using 2 radios. Also, we study the capacity of VoIP calls in the wireless mesh network environment. We figure out that mesh network can support 5 times more voice calls than wireless LAN.