Blocking Interference Mechanism in Networked Radios Under UWB HPM

ABSTRACT As a critical component of unmanned aerial vehicle (UAV) data link systems, networking radios used to create wireless ad‐hoc networks demonstrate considerable susceptibility to ultra‐wideband ultra‐wideband electromagnetic pulse (UWB‐EMP) irradiation, resulting in severe degradation of communication performance. This paper presents a systematic investigation based on irradiation experiments, which clearly reveal front‐door interference effects in networking radios exposed to UWB‐EMP. To elucidate the underlying interference mechanisms, a QPSK communication system model and an RF module circuit model were developed. These models indicate that the observed blocking interference is primarily attributable to non‐linear effects within the RF front‐end. Throughout the study, the BER was employed as the evaluation metric for both irradiation tests and QPSK system simulations, while the output waveform of the low‐noise amplifier served as the key indicator in circuit‐level simulations. Experimental results indicate that UWB‐EMP irradiation induces communication blackouts, with a data transmission success rate of only 66.7% within the specified duration. The antenna effectively couples UWB‐EMP energy into the communication system, causing nonlinear distortion in the RF module. This distortion significantly increases the BER, reaching up to 50% under the given simulation conditions and may even lead to complete system failure. Detailed analysis shows that: (1) at 5 kV irradiation, the LNA enters nonlinear operation, losing amplification capability for 3–7 ns before recovery; (2) at 10 kV, transistor damage becomes more severe, extending the LNA's dysfunction period to 3–30 ns; and (3) at 30 kV and 60 kV, complete transistor breakdown occurs, with recovery times prolonged to 70 ns and 105 ns, respectively. These findings provide essential theoretical and experimental foundations for enhancing the electromagnetic compatibility and protection of networking radios in ultra‐wideband electromagnetic pulse (EMP) environments.