Unmanned aerial vehicles (UAVs), representing advanced combat capabilities in new domains, have become essential weaponry in modern warfare. The proliferation of frequency-dependent equipment and rapid advancements in counter-UAV technologies have resulted in increasingly complex electromagnetic environments. High-power microwave (HPM) radiation, characterized by high power, tunable carrier frequency, and complex coupling effects, can effectively jam or damage UAV systems. Datalinks, acting as the UAV’s ‘brain’, are particularly vulnerable to HPM interference. Consequently, research into HPM coupling mechanisms and protection methods for UAV datalink is vital for enhancing UAV resilience.

This study investigates the coupling laws and protection methods of HPM radiation on the RF front-end of UAV datalinks.

Models of the datalink antenna and RF front-end PCB were developed using Computer Simulation Technology (CST) software. The antenna was irradiated with HPM pulses with variations in carrier frequency, pulse width, polarization direction, and rise time. The coupled voltage waveforms at the antenna output ports were analyzed. These voltages were injected into the receiver circuit model to determine the coupled voltage at the pins of the RF chip (Si24R1), thus simulating the complete HPM field-to-circuit coupling process. A 2.45 GHz PIN limiter was implemented for electromagnetic protection.

(1) The amplitude of the coupled voltage at the Si24R1 RF chip pins exhibited spiking behavior at high carrier frequencies. (2) Coupled voltage decreased significantly with increasing polarization angle. (3) Variations in pulse width and rise time had minimal effect on coupled voltage amplitude. (4) The PIN limiter significantly reduced the coupled voltages while maintaining signal reception quality, enhancing the datalink’s electromagnetic protection.

This work quantifies HPM coupling laws on RF front-end circuits under varying parameters. Implementing PIN limiter on the RF front-end significantly attenuates electromagnetic interference, providing a validated reference for UAV electromagnetic protection.