Anti-Jamming Modulation for OFDM Systems under Jamming Attacks

2025-10-02

AI Summary

To address the insufficient robustness of OFDM systems under unknown interference, this paper proposes an interference-resilient modulation and adaptive communication framework. The method employs a spreading matrix to map each symbol across multiple subcarriers, enhancing interference dispersion. It further introduces a two-stage dynamic mechanism: Stage I performs online estimation of interference parameters via a prior-free, approximate maximum-likelihood detector; Stage II adaptively selects between non-coherent and coherent modulation schemes based on the estimated parameters. Innovatively integrating spread-spectrum modulation, low-complexity detection, and interference-aware adaptive decision-making, the framework significantly reduces reliance on prior knowledge of interference characteristics. Simulation results demonstrate that, across diverse interference types and intensities, the proposed scheme achieves substantial bit-error-rate (BER) improvements over conventional OFDM and state-of-the-art interference-resilient methods, while maintaining high robustness and practical feasibility.

Technology Category

• Intelligent Robots: State Estimation
• Search and Optimization: Sampling/Simulation-based Search
• Cognitive Modeling & Cognitive Systems: Adaptive Behavior

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Novel mobile and WoT systems, and system-of-systems
• User Modeling, Personalization and Recommendation: Explainable and interpretable methods for personalization
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

In this paper, we propose an anti-jamming communication framework for orthogonal frequency-division multiplexing (OFDM) systems under jamming attacks. To this end, we first develop an anti-jamming modulation scheme that uses a spreading matrix to distribute each symbol across multiple subcarriers, enhancing robustness against jamming. For optimal demodulation at a receiver, we devise a maximum likelihood detection (MLD) method and its low-complexity variant tailored to our anti-jamming modulation scheme in scenarios with known jamming variance. We analyze the bit error rate (BER) of our modulation scheme to optimize its modulation order according to a jamming scenario. To adapt to dynamic and unknown jamming environments, we present a jamming-adaptive communication framework consisting of two phases: (i) a jamming-noncoherent phase and (ii) a jamming-coherent phase. In the jamming-noncoherent phase, we develop an approximate MLD method that operates without prior knowledge of jamming variance and enables the estimation of jamming parameters. In the jamming-coherent phase, we use these estimated parameters to optimize the proposed modulation scheme while employing the low-complexity MLD method. Simulation results demonstrate the superior BER performance of the proposed anti-jamming framework compared to existing OFDM communication frameworks across a wide range of communication and jamming scenarios.

Problem

• Developing anti-jamming modulation for OFDM systems under jamming attacks
• Creating adaptive detection methods for unknown jamming environments
• Optimizing modulation order and BER performance against jamming

Innovation

• Spreading matrix distributes symbols across subcarriers
• Maximum likelihood detection with low-complexity variant
• Two-phase adaptive framework estimates jamming parameters dynamically