摘要
Extensive research attentions have been devoted to studying cooperative cognitive radio networks(CCRNs),where secondary users(SU)providing cooperative transmissions can be permitted by primary users(PU)to use spectrum.In order to maximize SU’s utility,SU may transmit its own information during the period of cooperative transmission,which stimulates the use of covert transmission against PU’s monitoring.For this sake,this article reviews the motivations of studying covert communications in CCRN.In particular,three intelligent covert transmission approaches are developed for maximizing SU’s utility in CCRNs,namely,intelligent parasitic covert transmission(IPCT),intelligent jammer aided covert transmission(IJCT)and intelligent reflecting surface assisted covert transmission(IRSC).Further,some raw performance evaluations are discussed,and a range of potential research directions are also provided.
基金
supported by the National Natural Science Foundation of China under Grant 61825104, in part by the National Natural Science Foundation of China under Grants 61801518, 62201582
in part by the National Key R&D Program of China under Grant 2022YFC3301300
in part by the Key Research and Development Program of Shaanxi under Grant 2022KW-03
in part by the Young Talent fund of University Association for Science and Technology in Shaanxi under Grant 20210111
in part by the Natural Science Basic Research Program of Shaanxi under Grant 2022JQ-632
in part by Innovative Cultivation Project of School of Information and Communication of National University of Defense Technology under Grant YJKT-ZD-2202
