保密通信作为物联网安全的一项核心技术近些年受到了广泛关注。无人机(UAV)由于其高机动和灵活部署等特性,被认为是提高物联网通信安全的有力手段。针对当前物联网中UAV辅助保密通信频谱利用率问题,研究了UAV和地面设备到设备(Device-to...保密通信作为物联网安全的一项核心技术近些年受到了广泛关注。无人机(UAV)由于其高机动和灵活部署等特性,被认为是提高物联网通信安全的有力手段。针对当前物联网中UAV辅助保密通信频谱利用率问题,研究了UAV和地面设备到设备(Device-to-Device, D2D)通信系统频谱共享的系统保密容量最大化,提出了一种基于块坐标下降(Block Coordinate Descent, BCD)法的频谱共享算法,该算法通过联合优化系统中发送方(UAV和地面设备对)的传输功率和无人机轨迹,在确保地面设备对和UAV能够共存的情况下最大化接收方的保密容量。具体来说,该算法通过差分凸规划(Difference of Two Convex Functions, DC)方法优化固定轨迹下的系统功率,利用连续凸优化方法解决给定发射功率的UAV轨迹优化问题。仿真结果表明,所提方法在多种参数配置下都能有效提高系统的保密容量,并且和其他算法相比有更低的功率消耗。展开更多
This paper relates to an advanced open mobile communication system and method of integrating the mobile communications, wireless access systems and wired communications into one common platform architecture for China&...This paper relates to an advanced open mobile communication system and method of integrating the mobile communications, wireless access systems and wired communications into one common platform architecture for China's 4th generation mobile communications, supporting costeffective broadband voice, data and video services in wireless, mobile and wired environment with one single integrated mobile terminal device. The paper includes new architecture in the integrated mobile device and converged network access, and minimum modifi cation in the existing mobile telecommunication infrastructures. This paper introduces the long-term evolution strategy for China's TDD system platform towards China's future 4G mobile communications.展开更多
This paper presents a vehicle navigation and monitoring system scheme based on GIS/GPS/GPRS. The whole system consists of vehicle terminal and monitoring center, the monitoring center and the monitoring terminal compr...This paper presents a vehicle navigation and monitoring system scheme based on GIS/GPS/GPRS. The whole system consists of vehicle terminal and monitoring center, the monitoring center and the monitoring terminal comprises a communication server, communication server is only responsible for data storage and forwarding, the monitoring functions are completed by the monitoring terminal. Therefore, after the map matching, control terminal is performed on the device display to achieve real-time monitoring of vehicle location. The monitoring terminal can also be parameters of the moving vehicle accurate location, velocity and state the necessary query and transmission scheduling control instruction to carry out scientific scheduling and management, and improve operation efficiency. If the vehicle encountered an unexpected condition, harm or left the restricted area, it also can send alarm information to the monitoring terminal, and then the terminal can receive assistance and support in time.展开更多
文摘保密通信作为物联网安全的一项核心技术近些年受到了广泛关注。无人机(UAV)由于其高机动和灵活部署等特性,被认为是提高物联网通信安全的有力手段。针对当前物联网中UAV辅助保密通信频谱利用率问题,研究了UAV和地面设备到设备(Device-to-Device, D2D)通信系统频谱共享的系统保密容量最大化,提出了一种基于块坐标下降(Block Coordinate Descent, BCD)法的频谱共享算法,该算法通过联合优化系统中发送方(UAV和地面设备对)的传输功率和无人机轨迹,在确保地面设备对和UAV能够共存的情况下最大化接收方的保密容量。具体来说,该算法通过差分凸规划(Difference of Two Convex Functions, DC)方法优化固定轨迹下的系统功率,利用连续凸优化方法解决给定发射功率的UAV轨迹优化问题。仿真结果表明,所提方法在多种参数配置下都能有效提高系统的保密容量,并且和其他算法相比有更低的功率消耗。
文摘This paper relates to an advanced open mobile communication system and method of integrating the mobile communications, wireless access systems and wired communications into one common platform architecture for China's 4th generation mobile communications, supporting costeffective broadband voice, data and video services in wireless, mobile and wired environment with one single integrated mobile terminal device. The paper includes new architecture in the integrated mobile device and converged network access, and minimum modifi cation in the existing mobile telecommunication infrastructures. This paper introduces the long-term evolution strategy for China's TDD system platform towards China's future 4G mobile communications.
文摘This paper presents a vehicle navigation and monitoring system scheme based on GIS/GPS/GPRS. The whole system consists of vehicle terminal and monitoring center, the monitoring center and the monitoring terminal comprises a communication server, communication server is only responsible for data storage and forwarding, the monitoring functions are completed by the monitoring terminal. Therefore, after the map matching, control terminal is performed on the device display to achieve real-time monitoring of vehicle location. The monitoring terminal can also be parameters of the moving vehicle accurate location, velocity and state the necessary query and transmission scheduling control instruction to carry out scientific scheduling and management, and improve operation efficiency. If the vehicle encountered an unexpected condition, harm or left the restricted area, it also can send alarm information to the monitoring terminal, and then the terminal can receive assistance and support in time.