Priority channel selection based on detection history database

This paper proposes a new database-based two-stage channel selection method for cognitive radios. The proposed method consists of two stages, namely the database collection and signal detection parts. The database collects information about channels. When a cognitive radio needs to find an unoccupied channel for a transmission, it sends a query to the database. Based on the information collected to the database, the most probably unoccupied channels at requesting time are the best candidates when searching unoccupied channels, and these channels are submitted to the cognitive radio. The cognitive radio performs first the power level detection. Based on the power level information delivered from the database, a full signal detection is performed next to the channel with low enough power level to ensure that the channel is really unoccupied.