Research of Double Threshold Collaborative Spectrum Sensing Based on OFDM

In view of the shortage of the single threshold energy detection in spectrum sensing, the double threshold energy detection is studied. Combined with the characteristics of OFDM spectrum efficiency, the double threshold energy detection and OFDM system are combined. The method is on the basis of OFDM with the sub-channel as the user to be perceived. According to the available subcarrier number, the actual number of user to be perceived is determined, and the double threshold energy detection is conducted in subchannels. The data fusion center makes decisions by means of "or" criterion. The simulation results show that the method can well identify the main users, thus controlling the data transmission of OFDM .