Research On Transmitting And Receiving Optical Antenna In Ultraviolet Communication

As a supplement to wireless communication methods,UV communication is a new type of optical communication technology that uses ultraviolet light as a signal carrier to transmit information through space scattering.Among them,the day-to-day blind UV communication technology has attracted wide attention due to its good concealment,strong anti-interference ability,all-weather and non-line-of-sight communication and many other advantages.As an important part of wireless optical communications,optical antennas are of great significance to wireless optical communications systems.A good optical antenna design can greatly reduce the optical energy loss in optical communication,increase the communication distance,and enhance the received signal power,thereby improving the communication quality of the entire system.This topic has been studied from the perspective of the optical and transceiving antennas for the UV communication.First,two collimated transmitting antenna structures are proposed for the ultraviolet LED array light source.A transmissive transmitting antenna composed of a lens group is designed.The antenna can uniformly illuminate a circular area with a radius of 1.4m at a distance of 10 m.The beam divergence angle of ±30° is compressed to ±7.98°.The optical efficiency is 92.6%,and through the establishment of experimental systems,verify that the optical gain is 7.2,effectively improving the energy transmission efficiency.On this basis,the transmissive transmit antenna is used as a first-order collimation system,followed by the Cassegrain telescope-type optical reflective surface to constitute a two-stage cascaded optical transmitting antenna.Compared with the transmissive transmitting antenna,the hybrid transmitting antenna has a gain of 9 times and the beam spread angle is further compressed to ±2.28°,which is suitable for long-distance communication.Secondly,due to the consideration of antenna mobility in UV communication,a zoom structure was introduced into the design of the receiving optical antenna,and a continuous zoom receiving antenna with a zoom ratio of 3.2 times was designed with a focal length range of 125 to 258 mm.The field angle is ±2.44°?±5.03°,the total length of the system remains unchanged during zooming,and the detection surface is stable.According to the movement of each component in the zooming process,the program is written,the corresponding cam curve is drawn,and the subsequent cam structure is machined.