# A Linear Strong Constraint Joint Solution Method Based on Angle Information Enhancement
## 6 Conclusions  
This paper proposes a three-stage time-frequency synchronization method based on group peak time sequence tracking. In the first stage, coarse timing synchronization is achieved via group peak accumulation timing coarse synchronization algorithm for multi-window joint estimation. In the second stage, frequency offset estimation is performed using cyclic prefix correlation. Finally, fine timing synchronization at the chip level is realized through sliding cross-correlation with the primary synchronization signal. Furthermore, a multimodal positioning algorithm is introduced for heterogeneous measurement fusion in 5G systems. By employing high-precision angle-of-arrival obser  
Figure 12: Cumulative distribution map of positioning error in Region 1. Figure 13: Cumulative distribution map of positioning error in Region 2.  
vations as intermediate variables, a linear observation model is constructed. Modeling and analysis are conducted for various multimodal scenarios, leading to a closed-form solution of the position information. This approach enables robust and high-precision positioning performance, even under dynamic conditions with varying types and quantities of observations. Future work will focus on integrating 5G with inertial navigation systems to achieve continuous and robust positioning in complex environments. Conceptualization, Z.D. and Z.M. ; methodology, Z.M. and X.G. ; software, Z.M. ; validation, Z.M., P.L. and Z.D. ; formal analysis, Z.M. and K.Y. ; investigation, Z.M. ; resources, Z.M. and Z.D. ; data curation, Z.M. ; writing--original draft preparation, Z.M. ; writing--review and editing, Z.M. ; visualization, Z.M. ; supervision, Z.M. and Z.D. ; project administration, Z.M. 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 this study are included in this 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 of this research. The authors declare no conflicts of interest. References  
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