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A New Measurement Method for BDS Inter-Satellite Link Based on Co-Frequency Co-Time Full Duplex System
Hao Feng1,2, Zhuo Yang1,2, Hong Ma2
1Graduate School, Space Engineering University, Beijing 101416, China.
Sensors (Basel, Switzerland)
|September 19, 2025
Summary
This study introduces a Co-frequency Co-time Full Duplex (CCFD) system for BeiDou-3 satellites, significantly improving ranging accuracy and transmission efficiency over traditional methods. The new CCFD system achieves centimeter-level precision, enhancing satellite navigation performance.
Area of Science:
- Satellite Navigation Systems
- Radio Frequency Engineering
- Signal Processing
Background:
- BeiDou-3 inter-satellite links require high-precision ranging and large-capacity transmission.
- Traditional Time-Division Half-Duplex (TDHD) systems face limitations in accuracy, efficiency, and link establishment.
Purpose of the Study:
- To propose and validate a novel two-way measurement method using Co-frequency Co-time Full Duplex (CCFD) for BeiDou-3 inter-satellite links.
- To enhance ranging accuracy and transmission efficiency compared to existing TDHD systems.
Main Methods:
- Developed a dynamic link constraint model based on BeiDou-3 constellation configuration.
- Conducted a comprehensive link budget analysis for inter-satellite measurements.
- Derived the principles, system model, and error analysis for CCFD two-way measurement.
Main Results:
- CCFD system demonstrated feasibility and significant ranging accuracy improvements.
- Achieved 1.9 cm accuracy (51.3% enhancement) at 61.6 dBHz, surpassing TDHD's 3.9 cm.
- Further improved to 0.8 cm accuracy (66.8% enhancement) at 69.3 dBHz, outperforming TDHD's 2.2 cm.
Conclusions:
- The proposed CCFD technology substantially enhances BeiDou-3 satellite navigation system performance.
- CCFD offers a promising solution for future high-precision satellite communication and ranging applications.
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