Scholarlink

<p>In low Earth orbit positioning navigation and timing (LEO-PNT) systems, differential Doppler positioning is a primary technology, making the accuracy of Doppler measurements crucial for positioning performance. While the burst nature of LEO communication signals often leads to the use of fast fourier transform (FFT) for Doppler measurement, its accuracy is inherently limited by the transform’s point count. To address these limitations in tracking IRIDIUM-NEXT ring alert (IRA) burst signals, this paper proposes an ephemeris-assisted carrier Doppler tracking and measurement method, specifically designed for base station receivers and leveraging the characteristics of IRA signals. The Doppler effect resulting from satellite motion is predicted using two-line element (TLE) to reduce the dynamics, improving the convergence speed and tracking stability of the emerging signal. And during the reception of the signal, the corresponding phase discriminator and loop parameters are set to adaptively respond to the varying modulation. Experimental results demonstrate that the proposed method achieves a 73.85% average improvement in Doppler frequency tracking accuracy compared to the traditional FFT method and an 88.77% reduction in loop convergence time compared to the adaptive-bandwidth 3rd-PLL. The accuracy of the differential Doppler positioning is improved by 51.08% when using the Doppler measurements obtained by the proposed method. The tracking method proposed in this paper improves the stability and accuracy of Doppler tracking in the base station receiver by making optimal use of the orbital parameters and the burst signal characteristics.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Burst Doppler tracking and measurement in LEO-PNT base station receivers with ephemeris assistance

  • 期刊论文

  • 发表日期：

    2025年9月22日

查看全文
  • Wenfei Guo,
  • Weijun Feng,
  • Li Cheng,
  • Yitao Zhu,
  • Xiaoli Chen

摘要

In low Earth orbit positioning navigation and timing (LEO-PNT) systems, differential Doppler positioning is a primary technology, making the accuracy of Doppler measurements crucial for positioning performance. While the burst nature of LEO communication signals often leads to the use of fast fourier transform (FFT) for Doppler measurement, its accuracy is inherently limited by the transform’s point count. To address these limitations in tracking IRIDIUM-NEXT ring alert (IRA) burst signals, this paper proposes an ephemeris-assisted carrier Doppler tracking and measurement method, specifically designed for base station receivers and leveraging the characteristics of IRA signals. The Doppler effect resulting from satellite motion is predicted using two-line element (TLE) to reduce the dynamics, improving the convergence speed and tracking stability of the emerging signal. And during the reception of the signal, the corresponding phase discriminator and loop parameters are set to adaptively respond to the varying modulation. Experimental results demonstrate that the proposed method achieves a 73.85% average improvement in Doppler frequency tracking accuracy compared to the traditional FFT method and an 88.77% reduction in loop convergence time compared to the adaptive-bandwidth 3rd-PLL. The accuracy of the differential Doppler positioning is improved by 51.08% when using the Doppler measurements obtained by the proposed method. The tracking method proposed in this paper improves the stability and accuracy of Doppler tracking in the base station receiver by making optimal use of the orbital parameters and the burst signal characteristics.