# Fusion-Based Localization System Integrating UWB, IMU, and Vision
## 3 Tightly Coupled UWB/IMU Fusion Localization Based on Sliding-Window Factor Graph
### UIWB/IMU Fusion Localization
In future research, we plan to incorporate interference-aware strategies in future research, such as robust outlier detection, adaptive covariance tuning, and sensor confidence weighting, to improve reliability. Since the current system primarily performs localization in a two-dimensional plane, it does not fully account for dynamic variations in altitude. With the advancement of spatial operations, three-dimensional mobile platforms, such as unmanned aerial vehicles (UAVs), are expected to play a key role in indoor intelligent systems. Therefore, future research may extend to the development of 3D localization systems based on UAV platforms in order to meet the demands of higher-dimensional and more accurate localization applications. Moreover, although the current work mainly focuses on indoor scenarios due to the limitations of GNSS signals in such environments, we believe that the proposed method has the potential to be extended to outdoor or mixed environments. Future research may consider incorporating GNSS information to enhance localization robustness, especially in cases where UWB or visual features are limited. Although the present work targets indoor positioning, we recognize that the core fusion strategies may be applicable in other domains facing similar challenges. For example, high-frequency surface wave radar (HFSWR) systems also require robust multi-source data integration under interference. Inspired by recent advances in high-resolution signal processing for HFSWR [34; 35], future work may explore the cross-domain adaptation of our framework. Conceptualization, Z.D. and H.L. ; methodology, H.L. and X.G. ; software, H.L. ; validation, H.L., P.L. and Z.D. ; formal analysis, H.L. ; investigation, H.L. ; resources, H.L. and Z.D. ; data curation, H.L. ; writing--original draft preparation, H.L. ; writing--review and editing, H.L. ; visualization, H.L. ; supervision, H.L. and Z.D. ; project administration, H.L. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable. The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding authors. We thank the Research Centre for Convergence of Wireless Network Communication and Navigation for their support for this research. The authors declare no conflicts of interest. ## References

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