无人机机载测控天线自动选择算法

A Airborne Antenna Automatic Selection Algorithm in UAV TT&C Link

中大型无人机通常配备多幅天线来降低机体遮挡和空域覆盖不够的影响,传统地面测控站手动选择天线的方式存在准确性不高、时效性差、占用操控员精力等缺点。分析了先进无人机测控链路架构,提出基于无源天线方向图的自动天线选择算法,通过实测或仿真天线增益数据形成拟合曲线,根据地面站投影在飞机坐标系下的方位俯仰实现自适应天线选择。针对有源相控阵或定向天线,提出机体坐标系到相控阵天线坐标系的转换矩阵和波束指向算法。给出测控直扩波形信噪比计算方法,将信号质量算法作为卫星导航失效情况下自动天线选择的备份手段。所提算法在准确性、时效性和自动化水平上相对传统手动方式有较大提升,飞行试验数据表明本文算法有效支撑无人机与测控站的稳定可靠通信。

Large and medium sized UAVs are usually equipped with multiple TT&C antennas to reduce the impact of airframe shielding and insufficient airspace coverage.The traditional method of selecting antennas manually in ground TT&C stations has some disadvantages such as low accuracy,poor timeliness,and a low level of automation.The TT&C link architecture of advanced UAV is analyzed.An automatic antenna selection algorithm based on passive antenna pattern is proposed,which uses a fitting curve based on measured or simulated antenna gain data,along with the azimuth and pitch of the ground station projected into the UAVs coordinate system.The transformation matrix from the airframe to the phased array antenna coordinate system and the beam pointing algorithm is provided,which is suitable for phased array antenna or directional antenna.The signal quality algorithm is used as a backup method for automatic antenna selection when satellite navigation fails to function properly.Compared with the traditional manual mode,the algorithm is improved in automatic control capability,antenna selection accuracy and timeliness.The flight data show that the algorithm effectively supports the stable and reliable communication between UAV and TT&C station.