In an underlay cognitive radio network

secondary user (SU) is allowed to access the spectrum when the primary user (PU) is transmitting.At this time

both of SU and eavesdropper will be interfered by PU.Using cooperative jamming technology

the interference produced by PU can be used to improve the physical layer security of SU.Based on this

a novel cooperative physical layer security scheme will be proposed for an underlay cognitive radio network with multiple PUs and SUs.In the proposed scheme

in order to maximize the total security capacity obtained by all SUs under the premise of guarantee of PUs' communication quality

a suitable spectrum access and power control method is designed for SU.Moreover

considering the impact on the access stability of individual rational and selfish

the spectrum access selection problem is formulated as a one-to-one two-side matching.The stability of spectrum access can be guaranteed through building a stable matching between PUs and SUs.The simulation results show that through using the proposed scheme

the communication quality of PU can be guaranteed

and the total secrecy capacity obtained by all SUs can be efficiently improved.