Abstract: Cognitive radio is an intelligent technology of increasing spectrum utilization,which can change its transmitter parameters based on interaction with the environment where it operates.It can be used to improve the spectrum access and efficiency of the spectrum use;especially it enables an unlicensed user to use the licensed spectrum.It also makes network terminals more flexible.The key to share the spectrum is sensing spectrum reliably.A novel method of integrating forward is proposed and backward linear prediction with matrix QR decomposition based on the blinding sensing algorithm proposed by Parthapratim De.Simulation results demonstrate the new method can sense the spectrum void more reliably under the same wireless transmitting environment compared with the original blinding sensing algorithm.