【作者】 刘萍；

【导师】 赵太飞；

【作者基本信息】 西安理工大学 ， 通信与信息系统， 2020， 硕士

【摘要】 无人机(Unmanned Aerial Vehicle,UAV)因其有成本低、安全、对起降要求低等优势,在军民用领域发挥着重要的作用。未来的无人机将会朝着实战化、智能化、人机混合编队等方向发展。光电引导技术精度高,测量误差小。无线紫外光(Ultraviolet,UV)独特的通信方式在近年来成为广大研究学者的热点问题,它是利用空气中的微粒对紫外光的散射来达到通信的目的。这种新型通信方式具有非直视通信、不易被干扰、不受天气影响等优势。使用无线紫外光作为无人机导航的引导光源,在一定程度上弥补了 GPS导航的缺陷。本文将无线紫外光通信技术应用于无人机飞行引导方面,针对无人机飞行引导过程中的自主着陆、地形匹配、功率控制等问题进行了研究。主要研究内容如下:(1)提供一种无人机匹配地形飞行的无线紫外光引导方法,辅助无人机匹配不同地形飞行。提出一种基于紫外光的光功率控制方法,通过调整紫外信标发送端的角度和发射功率,使得到达无人机飞行平面的紫外光功率相等,保障无人机安全飞行。对功率控制方法进行了计算机仿真。实验结果表明,紫外光LED发送张角不超过80°时,功率容易控制,信标集成易于实现,且受地形、高度等因素影响较小。(2)搭建了一套无人机助降系统,该系统以经过编码的紫外LED阵列作为引导光源,可以通过紫外光通信获取无人机位置和高度引导无人机助降;研究了紫外LED竖直发光和斜发时在空中的覆盖区域,给出了覆盖区域面积的计算公式;此外我们还推导了紫外LED朗伯功率公式,该公式较传统的直视紫外光收发光功率公式不仅考虑了接收孔径还考虑了紫外LED的发散角,适用于任何紫外光朗伯光源。仿真结果表明,随着接收器角度的增大,紫外光LED的发散角越大,紫外光的功率衰减越快。当接收器不在光源法线方向且接收角度固定时,在该角度可以通过选择合适发散角的紫外LED,接收到最大的紫外光功率。综上所述,本文将紫外光应用于无人机飞行引导技术,为无人机助降和地形匹配提供了新方法,使得无人机可以适应不同天气、地形等复杂环境。本文的研究方法为低空空域无人机飞行引导提供了技术支持。更多还原

【Abstract】 Unmanned Aerial Vehicle(UAV)plays an important role in military and civilian fields because of its advantages of low cost,safety,and low requirements for takeoff and landing.In the future,unmanned aerial vehicles will develop in the direction of actual combat,intelligence,and hybrid man-machine formation.The photoelectric guidance technology has high precision and small measurement error.The unique communication method of wireless ultraviolet(Ultraviolet,UV)has become a hot issue of researchers in recent years.It uses the scattering of ultraviolet light by particles in the air to achieve the purpose of communication.This new communication method has the advantages of Non-direct-view communication,not easily interfered by,and not affected by weather.The use of wireless ultraviolet light as the guiding light source for UAV navigation has made up for the defects of GPS navigation to a certain extent.In this paper,wireless ultraviolet communication technology is applied to drone flight guidance,and the autonomous landing,terrain matching,power control and other issues in the course of drone flight guidance are studied.The main research contents are as follows:(1)Provide a wireless ultraviolet light guidance method for UAV to match terrain flight,assist UAV to match different terrain flight.An optical power control method based on ultraviolet light is proposed.By adjusting the angle and transmission power of the transmitting end of the ultraviolet beacon,the ultraviolet power reaching the flying plane of the drone is equal to ensure the safe flight of the drone.Computer simulation of the power control method.The experimental results show that when the transmission angle of the ultraviolet LED does not exceed 80°,the power is easy to control,the beacon integration is easy to implement,and is less affected by factors such as terrain and altitude.(2)This article builds a set of drone assisting system.This system uses the encoded ultraviolet LED array as the guiding light source,which can obtain the position and height ofthe drone through ultraviolet light communication.The coverage area of the LED in the sky when it emits vertically and obliquely gives the calculation formula of the area of the coverage area;in addition,we also derived the UV LED Lambertian power formula,which is more than the traditional direct-view UV light receiving and emitting power formula.Considering the receiving aperture and the divergence angle of the ultraviolet LED,it is suitable for any ultraviolet Lambertian light source.The simulation results show that as the receiver angle increases,the greater the divergence angle of the ultraviolet LED,the faster the power attenuation of the ultraviolet light.When the receiver is not in the normal direction of the light source and the receiving angle is fixed,at this angle,the maximum ultraviolet light power can be received by selecting an ultraviolet LED with an appropriate divergence angle.In summary,this article applies ultraviolet light to the drone flight guidance technology,which provides a new method for drone assist landing and terrain matching,so that the drone can adapt to different weather,terrain and other complex environments.The research method in this paper provides technical support for low altitude airspace UAV flight guidance.更多还原