## 5 Conclusions  
This article examines the performance enhancement of low-orbit satellite positioning systems in urban canyon environments, particularly under complex conditions with NLOS satellite signals. Initially, a theoretical signal model is developed, using a narrowband far-field source to capture the spatial characteristics of satellite signals. Next, a spatial correlation matrix is derived based on signal reception from a uniform surface array antenna, forming the basis for the spatial spectrum of the 2D-MUSIC algorithm. Additionally, an innovative method is proposed for pre-estimating elevation angles using the a priori information from satellite ephemeris. Building on this, an efficient, high-precision azimuth discrimination algorithm is developed, reducing dimensionality and simplifying computation. Simulation results demonstrate the effectiveness of the proposed positioning estimation method. The azimuth discrimination algorithm reduces computational complexity while maintaining high-precision angle estimation. The NLOS virtual satellite construction method is proposed to integrate NLOS satellite data into the positioning system, enhancing its accuracy in complex environments. Simulation experiments deploy a satellite positioning system using a uniform surface array antenna in a simulated environment containing both line-of-sight and non-line-of-sight satellite signals. The NLOS virtual satellite construction method significantly enhances positioning accuracy in NLOS environments, particularly when the number of visible satellites is limited. The experiments confirm that the proposed method effectively utilizes NLOS signals to improve the positioning accuracy without increasing hardware complexity. The findings in this paper provide valuable insights for designing effective NLOS signal processing strategies in low-orbit satellite positioning systems for urban canyon environments. Conceptualization, [PERSON]; methodology, J.G. ; supervision, J.G. ; writing--original draft preparation, J.G. ; writing--review and editing, J.G. All authors have read and agreed to the published version of the manuscript. **Funding:** This work was supported in part by the Science and Technology Project of Shenzhen under Grant JCYJ20200109113424990 and in part by the Marine Economy Development Project of Guangdong Province under Grant GDNRC [2020]014. **Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable. **Data Availability Statement:** The raw data supporting the conclusions of this article will be made available by the authors on request. **Conflicts of Interest:** The authors declare no conflicts of interest. * (22) [PERSON]; [PERSON]; [PERSON] A Computation Effective Range-Based 3D Mapping Aided GNSS with NLOS Correction Method. _J. Navig._**2020**, _73_, 1202-1222. [CrossRef]
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