无人机动态数据链路电磁辐射效应试验

Electromagnetic radiation effects on dynamic datalink of UAV

数据链路的电磁安全性成为制约无人机发展的突出问题,为提高无人机数据链的电磁环境适应能力,根据数据链路电磁敏感度随飞行状态变化的特点,设计并开展了动态数据链路连续波电磁辐射效应试验。结果表明:数据链工作信号强度影响系统的电磁敏感度。无人机常规工作状态下,带内干扰辐射场强阈值低于1 V/m,对应的自动增益控制(AGC)电压最大,达到190 V;此时,带内干扰容错能力强,误码随干扰功率增加而变大的趋势相对明显;最大规定误码阈值条件下,上行控制链路仍能正常工作。邻频干扰条件下,电磁干扰场强阈值随频偏增加而变大,对应的AGC电压相对减小;误码随干扰功率增大过程被压缩,数据链突发失锁效应。

The electromagnetic security of datalink becomes an outstanding issue for restricting the development of an Unmanned Aerial Vehicle(UAV). To improve the adaptability of the UAV’s datalink in the electromagnetic environment, a test method of electromagnetic radiation effects on the dynamic datalink is designed due to variable electromagnetic susceptibility depending on the flight state. Then the test of continuous wave radiation effects on the datalink is conducted. The results show that the electromagnetic susceptibility depends on the operation signal power. The electric field thresholds of the in-band interference is lower than 1 V/m under normal operations for UAV, but the corresponding Automatic Gain Control(AGC) voltage is the largest, reaching 190 V. Although the anti-interference capability of the datalink is weak, but its error tolerance performance is good. The increasing trend of the number of bit errors with the increase of Electromagnetic Interference(EMI) signal power is obvious. When the amount of bit errors approaches the limited maximum, the uplink can still work properly. Besides, the frequency offset EMI may suppress the BER increasing process at the critical lost-link state resulting in the disruption of the datalink. The corresponding susceptibility threshold becomes larger as the frequency offset increases, but the corresponding AGC voltage is relatively reduced.