针对无人机应用场景频谱效率较低的问题,提出一种结合认知无线电技术的多无人机通信网络谱效优化方案.首先基于协作频谱感知,建立空地信道下多机协作的认知无人机网络模型,设置无人机(unmanned air vehicle,UAV)数量、感知时间和判决门...针对无人机应用场景频谱效率较低的问题,提出一种结合认知无线电技术的多无人机通信网络谱效优化方案.首先基于协作频谱感知,建立空地信道下多机协作的认知无人机网络模型,设置无人机(unmanned air vehicle,UAV)数量、感知时间和判决门限等优化参数,在此基础上提出高谱效联合优化算法对构建的非凸优化问题求解,最后分析无人机飞行过程中谱效的变化情况.仿真结果表明,存在最优感知时间使系统谱效获得最大值,且UAV数量和判决门限等因素会影响该谱效最优值;提出的高谱效联合优化算法具有较好的收敛性,有效提高了UAV次级认知网络的频谱效率.展开更多
A hybrid carrier(HC) scheme based on weighted-type fractional Fourier transform(WFRFT) has been proposed recently.While most of the works focus on HC scheme's inherent characteristics, little attention is paid to...A hybrid carrier(HC) scheme based on weighted-type fractional Fourier transform(WFRFT) has been proposed recently.While most of the works focus on HC scheme's inherent characteristics, little attention is paid to the WFRFT modulation recognition.In this paper, a new theory is provided to recognize the WFRFT modulation based on higher order cumulants(HOC). First, it is deduced that the optimal WFRFT received order can be obtained through the minimization of 4 th-order cumulants, C_(42). Then, a combinatorial searching algorithm is designed to minimize C_(42).Finally, simulation results show that the designed scheme has a high recognition rate and the combinatorial searching algorithm is effective and reliable.展开更多
文摘针对无人机应用场景频谱效率较低的问题,提出一种结合认知无线电技术的多无人机通信网络谱效优化方案.首先基于协作频谱感知,建立空地信道下多机协作的认知无人机网络模型,设置无人机(unmanned air vehicle,UAV)数量、感知时间和判决门限等优化参数,在此基础上提出高谱效联合优化算法对构建的非凸优化问题求解,最后分析无人机飞行过程中谱效的变化情况.仿真结果表明,存在最优感知时间使系统谱效获得最大值,且UAV数量和判决门限等因素会影响该谱效最优值;提出的高谱效联合优化算法具有较好的收敛性,有效提高了UAV次级认知网络的频谱效率.
基金supported by the National Natural Science Foundation of China(6127125061571460)
文摘A hybrid carrier(HC) scheme based on weighted-type fractional Fourier transform(WFRFT) has been proposed recently.While most of the works focus on HC scheme's inherent characteristics, little attention is paid to the WFRFT modulation recognition.In this paper, a new theory is provided to recognize the WFRFT modulation based on higher order cumulants(HOC). First, it is deduced that the optimal WFRFT received order can be obtained through the minimization of 4 th-order cumulants, C_(42). Then, a combinatorial searching algorithm is designed to minimize C_(42).Finally, simulation results show that the designed scheme has a high recognition rate and the combinatorial searching algorithm is effective and reliable.