## 6 Conclusions  
This study demonstrated the feasibility of acquiring high-resolution shipborne fluxgate magnetic data utilizing a paramagnetic aluminum-alloy USV, which significantly reduces magnetic interference, particularly the duration of VM. We confirmed that robust correction for vessel attitude and induced magnetization remains essential for accurate vector data, even with paramagnetic platforms. Specifically, a comparative analysis of existing correction methods (Equations (2)-(4)) revealed that Equation (3) [25] demonstrated the most effective correction performance. Despite effective filtering of high-frequency noise, two key challenges requiring further attention were identified: residual low-frequency VM effects associated with eddy currents during vessel turns, and a consistent offset error (approximately 200 nT) when compared to towed scalar data. This offset presents an inherent limit for precise magnetic field measurements, even with advanced correction strategies. These persistent discrepancies highlight the challenges in obtaining reliable magnetic fields. The methodologies validated here show potential for extending high-resolution vector magnetic surveys using paramagnetic unmanned platforms. Future work should focus on developing advanced VM correction techniques, optimizing sensor placement, and integrating complementary geophysical data. Additionally, research on the potential impact of the platform's electrical conductivity characteristics on magnetic response should also be pursued. These efforts will ultimately contribute to significantly enhancing the accuracy and resolution of vector magnetic anomaly maps derived from unmanned platforms. **Supplementary Materials:** The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/s25144511/s1](https://www.mdpi.com/article/10.3390/s25144511/s1)]([https://www.mdpi.com/article/10.3390/s25144511/s1](https://www.mdpi.com/article/10.3390/s25144511/s1)), Figure S1: Comparison of ambient magnetic field between IGRF-13 model [30] and actual measurements at the base station. (Page 2). Figure S2: shows Frequency and time-frequency analysis (FFT, STFT, CWT) of magnetic data from Sensor 1 and Sensor 2. Figure S3: CWT analysis of magnetic field measurements taken by a person manually carrying the fluxgate magnetometer in an environment without electromagnetic noise. Figure S4: Fast Fourier transform (FFT) analysis showing the effects of Butterworth low-pass filtering applied during the anti-aliasing preprocessing. Figure S5: The corrected magnetic anomaly of the entire track by Equation (3). Figure S6: Magnetic data correction results for the ferromagnetic R/V Kairei (KR05-17). Figure S7: Comparison of magnetic anomaly components (X, Y, Z) and yaw change. Figure S8: Comparison of corrected shipborne fluxgate magnetometer data with towed scalar magnetometer data over a cross-over track line. Table S1: Comparison of correction coefficients using different suggested methods for the ferromagnetic R/V Kairei. **Author Contributions:** Conceptualization, H.C.; methodology, S.C. and M.K. ; software, S.C.; validation, S.C., H.C. and M.K. ; formal analysis, S.C.; investigation, G.M., Y.P. ; resources, G.M. and Y.P. ; data curation, G.M. and Y.P. ; writing--original draft preparation, S.C.; writing--review and editing, H.C.; visualization, S.C. and M.K. ; supervision, H.C.; project administration, H.C.; funding acquisition, H.C. All authors have read and agreed to the published version of the manuscript. **Funding:** This study acknowledges the support of the National Research Foundation of Korea's Sejong Science Fellowship (NRF-2021R1C1C2003742), the Basic Research Laboratory (NRF-2022R1A4A3027001), and the National Research Foundation of Korea's G-LAMP project support (RS-2023-00301938), KMI(RS-2022-KM220610), KIMST funded by the Ministry of Oceans and Fisheries (RS-2023-00259686). **Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable.