系留球和地面之间的自由空间光通信中继系统设计与验证

Design and Verification of Free Space Optical Communication Relay Between Ground and Tethered Ball

目前微波移动中继网络存在中继距离短、数据传输速率慢、功耗高、工作频率受限等问题。本文使用激光通信技术构建了一个中继系统,该系统实现了系留球和地面基站之间红外高清图像数据的实时转发,通信距离超过20 km。实验的成功为激光通信技术作为机载通信中继站的应用提供了技术参考。针对初始瞄准指向角度不可预测、平台姿态快速变化等特殊场景,提出了一种用于确定扫描角域的评估方法和姿态稳定性补偿的方案来解决这些问题。通过4阶Runge-Kutta迭代方法规避复杂的微积分计算,提高了扫描算法的精度。将基于目标空间位置和自身姿态变化的数据通过前馈补偿算法引入到闭环跟踪系统的速度环中,有效提高了系统的跟踪稳定性。未来将实现空对空的激光链路中继网络实验。

There are currently some deficiencies with microwave mobile relay networks,such as short relay distance,sluggish data transfer rate,high power consumption,and limited operating frequency.This paper builds a relay system using laser communication technology to complete real-time forwarding of infrared high-definition data within a distance of more than 20 km from the tethered aerostat and the ground base station.This experiment’s success serves as a technical reference for the use of laser communication technology as an airborne communication relay station.A scanning acquisition scheme and attitude stability compensation scheme based on probability statistics are proposed to address the uncertain initial pointing angle and the external conditions of the rapid change of platform attitude.To avoid the complex integral calculation,this paper proposes a method based on the fourth-order Runge-Kutta to improve the algorithm’s accuracy while ensuring the function’s realization.The feedforward speed is introduced into the speed loop of the closed-loop tracking system based on the spatial position of the target and the change in its own attitude,which effectively improves the system’s tracking stability.We plan to conduct experiments on relaying laser links in air-to-air networks in the future.