无人机装备自主式保障系统研究

目前我军无人机装备采用事后维修、定期维修、预防性维修等维修保障方式,存在故障诊断及修复能力差、维修资源繁多、保障费用急剧增长等问题。充分考虑我军无人机装备技术特点及现行维修保障体制,文中创新性地提出了构建适合我军无人机装备的自主式保障系统;并对系统组成、故障模式影响及危害性分析、测试性设计技术、机载故障快速诊断及自修复技术、预测与健康管理技术、分布式信息融合技术等关键技术进行重点研究。该系统为我军新型信息化装备提供了新的维修保障模式,并可提高我军无人机装备的一体化、精确化保障水平。     

自主空中加油会合过程中飞行制导律设计

针对目前自主空中加油亟需解决的会合问题,采用带有末端角约束的比例导引方法,实现了受油机导引进入加油区域,加油机采用非线性制导算法跟踪赛马场跑道线飞行,并给出了有风条件下非线性制导算法可能失效的解决办法。引入虚拟目标和虚拟加油机的概念,保持受油机和加油机在会合上的时间同步,设计了相应的速度控制器。利用Matlab/Simulink搭建仿真平台对空中加油会合制导律进行了仿真验证,仿真结果表明设计的制导律能满足自主空中加油的会合要求。     

无人机自组网技术综述与发展展望

无人机自组网(Unmanned Aerial Vehicle Ad Hoc Network,UAVANET)主要应用于现代数字科技战场,具备传统无线自组织网络的快速组网、多跳传输和多任务协作等特点,同时拥有更高的抗毁性.无人机自组网能确保网络运行的灵活性和顽健性,但是在实际组网过程中,网络结构和组网方式的不同对作战能力...     

基于面积特征的城区航空影像匹配方法

基于特征的影像匹配是一类极为广泛和重要的方法。已有的研究体现出了特征对于实施最为匹配的影像之一－－城区航空影像有着极为明显的优越性。文中给出一种新的匹配目标函数的构建，并基于此提出一种城区航空影像匹配算法，给出了算法的实现过程，并以部分东京城区图进行了试验，结果表明文中的方法具有乘法明了，可靠易行和抗旋转性的优点。     

航空相机成像技术研究

无论是军事领域战术和战略侦查,或者是民用领域测绘、精细农业、海岸资源勘察和地图导航等应用,随处可见航空相机的身影.本文先介绍了几款20世纪典型的航空胶片相机以及它们的工作方式,然后将航空数字相机按工作方式分成了扫描型航空相机、步进凝视型相机和多镜头数字相机3类,简要介绍了其工作方式的原理及特点,并分别列举了相应的航空数字相机.最后对航空相机发展趋势进行了总结与展望.     

Efficient data management and control over WSNs using SDN‐enabled aerial networks

The recent developments in collaborative search, acquisition, and tracking have hoisted the geographical barrier. The network between unmanned aerial vehicles (UAVs) and wireless sensor networks (WSNs) is one such collaboration, which comprises battery‐powered static sensor nodes that act as sources and sinks and UAVs that act as relays. This collaborative network presents with opportunities and advantages, but at the same time, configuration of such networks is an arduous task. The WSN nodes are characterized by constant depleting power. Their network itself requires constant management and reconfiguration. These requisites can be slaked through the formation of an efficient data dissemination algorithm, which acclimates according to the network state. Considering this, a data dissemination approach is presented in this paper, which constructs a virtual topology predicated on the charge of WSN nodes utilizing software‐defined networks (SDNs) through UAVs. The topology is constantly monitored and reconfigured when required. The aerial nodes are equipped with multiple‐input multiple‐output (MIMO) antennas in order to facilitate simultaneous communication with the ground nodes, the base station, and the SDN controller. An efficient sleep timer and backoff counter strategies are also utilized by the proposed approach. The SDN controller facilitates the topology formation and maintenance of a sleep timer and a backoff counter. The proposed model is compared with clustered hierarchical layouts and hexagonal cell layouts through the network simulations. The results suggest significant improvements in the proposed model for various metrics, such as lifetime, delay, latency, delivery ratio, and throughput in comparison with the existing solutions.     

航空摄影测量技术在土地规划中的应用

随着社会经济的高速发展和航空摄影技术的不断开发,相应的测量技术在各个领域得到了广泛的应用。尤其是在土地规划工作中,航空摄影测量技术的应用不仅有助于提升土地观测和分析能力,也间接地促进了土地资源利用率的提升。文章基于航空摄影测量技术,从土地规划工作角度出发,简要地分析测量技术的特点以及应用方法,希望能对相关工作人员的工作提出有价值的建议。     

Passive Localization of Signal Source Based on UAVs in Complex Environment

For the influence caused by multipath fading and non-line-of-sight(NLOS)transmission,it is challenging to accurately localize a moving signal source in complex environment by using the wireless sensor network(WSN)on the ground.In this paper,we establish a special WSN in the sky to address this challenge,where each sensor is loaded on an unmanned aerial vehicle(UAV)and the operation center of all the UAVs is fixed on the ground.Based on the analyzing of the optimal distribution and the position error calibration of all the sensors,we formulate the localization scheme to estimate the position of the target source,which combines the time difference of arrival(TDOA)method and the frequency difference of arrival(FDOA)method.Then by employing the semidefinite programming approach,we accurately obtain the position and velocity of the signal source.In the simulation,the validity of the proposed method is verified through the performance comparison.     

Implementation of mmWave long-range backhaul for UAV-BS

Uncrewed aerial vehicles (UAVs) have become a vital element in nonterrestrial networks, especially with respect to 5G communication systems and beyond. The use of UAVs in support of 4G/5G base station (uncrewed aerial vehicle base station [UAV-BS]) has proven to be a practical solution for extending cellular network services to areas where conventional infrastructures are unavailable. In this study, we introduce a UAV-BS system that utilizes a high-capacity wireless backhaul operating in millimeter-wave frequency bands. This system can achieve a maximum throughput of 1.3 Gbps while delivering data at a rate of 300 Mbps, even at distances of 10 km. We also present the details of our testbed implementation alongside the performance results obtained from field tests.     

航空视频图像定位技术

讨论航空摄影图像的系统几何校正方法,针对机载摄像平台对地观测系统,建立从相机坐标系到地球坐标系的一系列空间坐标系统。根据各个坐标系相互转换关系,建立系统几何校正模型,对图像进行系统几何校正计算,完成图像定位。实验结果表明在有激光测距数据参与情况下,提高原模型的校正计算精度,能够有效完成航拍视频图像的校正和定位计算。