振动与远场湍流对机载精跟踪终端的影响

Effect of Vibration and Far Field Turbulence on the Fine Tracking of Airborne Optical Ccommunication Terminal

为了实现机载光通信终端小型化、高准确度的要求,依据机载平台振动功率谱特点设计了以FPGA为核心的小型机载精跟踪光通信终端.分别通过室内模拟跟踪与扰动抑制、远场信标探测与通信评估实验对精跟踪系统的性能进行了验证.分析了精跟踪系统对机载平台振动的抑制效果以及不同湍流强度对跟踪造成的影响.在远场3.4km进行大气湍流验证实验,通过角速度模拟了飞机到地面距离20~30km,飞行速度700~900km/h时的通信实验.实验表明,精跟踪系统对机载平台的振动具有较强的抑制能力,系统跟踪准确度为3μrad左右;精跟踪可以使机载光通信模拟运动时的接收光功率提高4~5.9dB.系统搭建灵活,跟踪准确度高.

In order to reduce the volume and power consumption and improve the tracking accuracy, a small airborne fine tracking system with FPGA based on the characteristics of airborne platform vibration power spectral density was desighed and developed. To verify the fine tracking system ability, simulation tracking and disturbance rejection experiments, far-field beacon detection and communication experiments were carried out, the airborne platform vibration suppressed effect and turbulence impact on fine tracking in various intensity were analyzed. In 3.4km far-field atmospheric turbulence experiment, a aircraft to ground communication through angular velocity was simulated. Simulation distance was about 20~ 30 km and flight speed was about 700 ~ 900 km/h. The experimental results show that, the fine tracking system has strong rejection effect on airborne platform vibration, the tracking accuracy is about 3 Brad. The receiving signal power can be improved 4 ~ 5. 9 dB in simulated aircraft to ground communication experiment. The fine tracking system has the characteristics of flexibility and high accuracy.