Collaborative spectrum sensing in cognitive radio using hard decision combining with quality information

We propose a collaborative spectrum sensing scheme for cognitive radio using hard decision in combination with quality information. This scheme necessitates to determine three thresholds at the local detector. One threshold is determined by a pre-specified local probability of false alarm, and the other two optimal thresholds are found using distance measure criteria. Simulation results show that the scheme outperforms conventional hard decision combining. We also evaluate the scheme under imperfect reporting channels, modeled as binary symmetric channels with varying binary error probabilities.