Multi-slot optimized index modulation based on FHSS for efficient anti-jamming

Abstract

The more sophisticated reactive follower jamming has become a critical challenge as traditional anti-jamming techniques including frequency hopping spread spectrum (FHSS) and index modulation based on FHSS (IM-FHSS) demonstrate insufficient robustness. To address this challenge, we propose a novel anti-jamming method termed multi-slot optimized index modulation based on frequency hopping spread spectrum (MSO-IM-FHSS). The proposed method innovatively integrates information transmission across multiple time slots, utilizing distinct activation states to convey data through subcarriers. Crucially, the jammer remains unaware of the activation states and their roles, while the states of the time slots are predefined and synchronized to ensure secure communication. At the receiver end, both fixed and optimal threshold detectors are employed to accurately decode the received signals. Theoretical analysis and simulation results show that MSO-IM-FHSS substantially outperforms traditional FHSS and IM-FHSS in terms of anti-jamming capability, attributed to its efficient utilization of both time and frequency domains. This advancement not only enhances communication reliability but spectrum resource utilization, offering a robust solution for modern wireless communication systems.