# Jamming Detection and Suppression Technique for OTFS Systems in an AWGN Channel
## 1 Introduction  
The sixth-generation (6G) network is envisioned as a groundbreaking technology that enables seamless terminal applications across terrestrial and non-terrestrial domains, such as self-driving autonomous cars, high-speed trains, unmanned autonomous vehicles (UAVs), and low-earth-orbit (LEO) satellites [1, 2, 3]. Future 6G networks are anticipated to handle mobility speeds of up to 1000 km/h, representing a significant advancement over the capabilities of previous generations [4, 5]. A key challenge in these scenarios is ensuring reliable communication in environments characterized by high mobility. Orthogonal time frequency space (OTFS) is a novel two-dimensional (2D) modulation technique that offers superior resilience to Doppler and delay effects compared to conventional orthogonal frequency division multiplexing (OFDM) [6, 7]. In recent years, a variety of studies have been conducted on the application of OTFS in different scenarios. In [8], the authors proved that the OTFS modulation is robust to carrier frequency offsets and performs better than OFDM modulation in LEO satellite communications. The Doppler interferencein OTFS-based LEO satellite systems is analyzed in [9], and a simple yet practical solution to mitigate this interference is subsequently proposed. Furthermore, the authors in [10] proposed a multiple input multiple output (MIMO)-OTFS-based random access method for cooperative LEO satellite networks. Since 6G systems will adopt integrated space-air-ground-sea communications to achieve ubiquitous connectivity, anti-Doppler modulation and demodulation schemes, including OTFS and second-order time-frequency (SOTF) modulation, for high-mobility satellite-UAV communications were studied in [11; 12; 13]. Similar to OFDM, OTFS systems are also vulnerable to jammings [14]. Therefore, how to mitigate the impact of jamming in these communication systems has become a challenge. There have already been several studies on the anti-jamming capabilities of OTFS. In [15], the authors explored narrow-band interference (NBI) in OTFS systems, emphasizing that OTFS demonstrates a certain level of robustness against NBI. In [16], an energy concentration NBI suppression method was proposed by designing the translation matrices and interference nulling. To address Barrage Jamming (BJ) in electromagnetic battlefield environments, the authors in [17] designed an OTFS with an Index Modulation (OTFS-IM) system and analyzed the impact of BJ on its performance. In [18; 19], sparse code multiple access (SCMA) and a frequency hopping mechanism were proposed for NBI in the next generation of the Internet of Things (IoT). The non-uniform impact of jamming signals, such as NBI and periodic impulse noise (PIN), on OTFS systems was investigated, and a resource hopping method for OTFS-SCMA was developed to suppress severe interference [20]. In addition, researchers have proposed a variety of algorithms to address the problem of jamming detection [21]. Several notable approaches have been introduced, such as consecutive mean excision (CME) [22], forward consecutive mean excision (FCME) [23; 24], FCME with double-threshold enhancement [25], and FCME incorporating adjacent cluster combining (ACC) techniques [26; 27]. The CME algorithm operates under the assumption that the original received signal is jamming-free and iteratively compares signal amplitudes against an updated threshold to identify the jamming.The FCME algorithm assumes low-amplitude signals are jamming-free and uses lower detection thresholds to avoid missing low-power interference. However, its sorting process adds complexity, hindering hardware implementation. In summary, research on low-complexity jamming detection and suppression methods for OTFS remains limited. In this work, a frequency-domain anti-jamming technique was explored, utilizing a time-domain overlapping window strategy to reduce interference sidelobes while mitigating the degradation of the signal-to-noise ratio (SNR) caused by the window function.