Impact of Pilot-Based Smart Jamming on OFDM-Based Communication Systems: BER Degradation and Interference Pattern Analysis

In the context of electronic countermeasures for orthogonal frequency division multiplexing (OFDM) systems, existing pilot-based smart jamming schemes primarily focus on the least square (LS) algorithm and only consider the ideal scenario where the interference signal and the target signal are perfectly time-frequency synchronized at the receiver. However, current OFDM systems tend to adopt the channel estimation algorithm based on discrete fourier transform (DFT), and it is challenging to achieve ideal synchronization between the interference signal and the target signal in practical jamming systems. These factors highlight the deficiencies in the theoretical analysis of existing pilot jamming schemes and their limited engineering applicability. To address these shortcomings, this paper considers the time-frequency offsets between the interference signal and the target signal, constructs the OFDM jamming system model based on DFT-based algorithm, and carries out theoretical analysis and simulation verification. The results show that, after considering the time-frequency offsets, the existing interference sequence retains robust jamming performance under DFT-based algorithms.