With the increasing number of communication devices and the complexity of communication environments,unmanned aerial vehicles(UAV),due to their flexible deployment and convenient networking capabilities,have shown sig...With the increasing number of communication devices and the complexity of communication environments,unmanned aerial vehicles(UAV),due to their flexible deployment and convenient networking capabilities,have shown significant advantages in tasks such as high-density communication areas and emergency rescue within special communication scenarios.Considering the openness of air-toground wireless communication,it is more susceptible to eavesdropping attacks.As a result,the introduction of physical layer security(PLS)in UAV communication systems is crucial to safeguard the security of transmitted data.In this paper,we investigate the PLS issues in a UAV cooperative communication system operating in Nakagami-m fading channels with the presence of friendly interference.It considers the effects of imperfect successive interference cancellation(i SIC)and power allocation coefficients on system performance based on non-orthogonal multiple access(NOMA)techniques.By deriving closed-form expressions for the outage probabilities at the receiving users and the intercept probability of UAV eavesdropper(U-EAV),the performance of the considered cooperative UAV-assisted NOMA relay system with the presence of friendly interference is evaluated.展开更多
THE village of Xujiawan is a quiet place these days. Except for a couple of old people chatting in front of their homes,there are no young people to be seen."All the young people have gone,working in the cities t...THE village of Xujiawan is a quiet place these days. Except for a couple of old people chatting in front of their homes,there are no young people to be seen."All the young people have gone,working in the cities to make money,"Wang Lirun,the village Party secretary,said.展开更多
Many local shoppers are buying merchan- dise as gifts,especial- ly around traditional Chinese festivals. Olympic souvenirs are considered a generous and tasteful choice. OLYMPIC merchandise ap- preciates rapidly and a...Many local shoppers are buying merchan- dise as gifts,especial- ly around traditional Chinese festivals. Olympic souvenirs are considered a generous and tasteful choice. OLYMPIC merchandise ap- preciates rapidly and at a high rate-the price of a 2004 Olympics souvenir badge,for example,has gone up 10 fold,"says Gu Bingfu,director of the Sports Branch of the China Association of Collectors."The price of a poster from the 1988展开更多
IN the village where I was born,rising prices are the talk of the town.Jiaojiazhuang is in Hebei Province,some 300 kilometers from Beijing.Surrounded by hills,the village has a population of 1,500,and only one road li...IN the village where I was born,rising prices are the talk of the town.Jiaojiazhuang is in Hebei Province,some 300 kilometers from Beijing.Surrounded by hills,the village has a population of 1,500,and only one road linking the settlement to the outside world.But since the reform and opening-up policy was instigated 30 years ago,every aspect of life,even for those in such out-of-the-way places,has become tied up with money.展开更多
基金supported by the National Natural Science Foundation of China under Grant(61901201,62001359)the Tianyou Youth Talent Lift Program of Lanzhou Jiaotong Universitythe Key Research and Development Project of Lanzhou Jiaotong University(ZDYF2304)。
文摘With the increasing number of communication devices and the complexity of communication environments,unmanned aerial vehicles(UAV),due to their flexible deployment and convenient networking capabilities,have shown significant advantages in tasks such as high-density communication areas and emergency rescue within special communication scenarios.Considering the openness of air-toground wireless communication,it is more susceptible to eavesdropping attacks.As a result,the introduction of physical layer security(PLS)in UAV communication systems is crucial to safeguard the security of transmitted data.In this paper,we investigate the PLS issues in a UAV cooperative communication system operating in Nakagami-m fading channels with the presence of friendly interference.It considers the effects of imperfect successive interference cancellation(i SIC)and power allocation coefficients on system performance based on non-orthogonal multiple access(NOMA)techniques.By deriving closed-form expressions for the outage probabilities at the receiving users and the intercept probability of UAV eavesdropper(U-EAV),the performance of the considered cooperative UAV-assisted NOMA relay system with the presence of friendly interference is evaluated.
文摘THE village of Xujiawan is a quiet place these days. Except for a couple of old people chatting in front of their homes,there are no young people to be seen."All the young people have gone,working in the cities to make money,"Wang Lirun,the village Party secretary,said.
文摘Many local shoppers are buying merchan- dise as gifts,especial- ly around traditional Chinese festivals. Olympic souvenirs are considered a generous and tasteful choice. OLYMPIC merchandise ap- preciates rapidly and at a high rate-the price of a 2004 Olympics souvenir badge,for example,has gone up 10 fold,"says Gu Bingfu,director of the Sports Branch of the China Association of Collectors."The price of a poster from the 1988
文摘IN the village where I was born,rising prices are the talk of the town.Jiaojiazhuang is in Hebei Province,some 300 kilometers from Beijing.Surrounded by hills,the village has a population of 1,500,and only one road linking the settlement to the outside world.But since the reform and opening-up policy was instigated 30 years ago,every aspect of life,even for those in such out-of-the-way places,has become tied up with money.
