Impact of Channel Switching in Energy Constrained Cognitive Radio Networks

In this letter, we investigate the energy efficiency of multichannel spectrum access in cognitive radio networks. We consider two channel access schemes. In one case, a secondary user (SU) is assigned multiple channels and the channels are switched whenever a primary user (PU) returns. In the other, the SU operates on a single channel without switching to other channels. We develop an analytic framework on achievable channel utilization and energy consumption performance of the SU. From the results, we examine the trade-off between SU channel utilization and energy consumption, and identify the PU traffic conditions where one scheme outperforms the other.