Journal of IKEEE (전기전자학회논문지)

Institute of Korean Electrical and Electronics Engineers (한국전기전자학회)
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Comparison on Various Acquisition Method for GPS L1 C/A

GPS L1 C/A 기반의 신호 획득부 구현 및 비교

  • Park, Jiwoon (Dept. of Electronics Engineering, Chungnam National University) ;
  • Yoo, Hoyoung (Dept. of Electronics Engineering, Chungnam National University)
  • Received : 2020.06.17
  • Accepted : 2020.06.24
  • Published : 2020.06.30
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Abstract

GPS is a representative satellite navigation system that provides users with accurate location and time information. GPS L1 C / A is opened for civilian and thus utilized in various fields. When the satellite signal reaches the receiver, signal acquisition unit of the digital signal processing hardware searches and acquires the signal among visible satellites. The signal acquisition unit has different implementation methods depending on the signal searching method, such as serial search acquisition, parallel frequency search, parallel code phase search. In this paper, we compare and analyze the three representative acquisition hardwares using live GPS L1 C/A signals. According to the comparison, the parallel code phase search acquisition outperforms the other methods due to reduction of the number of the searchings and a high resolution.

대표적인 위성 항법 시스템인 GPS는 사용자에게 위치와 시간을 제공한다. GPS L1 C/A는 민간용으로 개발되어 다양한 분야에서의 높은 활용도를 보인다. 위성 신호가 수신기에 도달하면 디지털 신호 처리단의 신호 획득부에서 가시 위성의 신호를 검색 후 획득하고, 획득한 신호는 신호 추적단에서 실시간으로 신호를 추적하며 항법 메시지를 추출한다. 신호 획득부는 직렬 검색 획득, 병렬 주파수 검색 획득, 병렬 코드 위상 검색 획득 등 신호 검색 방식에 따라 구현 방식이 달라지는데, 본 논문에서는 세 가지 검색 방식에 따라 GPS L1 C/A코드용 신호 획득부를 구현하고 각각을 비교한다. 직렬 검색 획득과 병렬 주파수 검색 획득에 비해서 병렬 코드 위상 검색 획득은 검색 횟수를 줄일 수 있고 높은 해상도의 상관값을 가질 수 있기 때문에 계산과정 중 필요한 연산의 복잡도를 줄인다면 항법 시스템의 빠른 동작을 위해서 최적의 검색 방식으로 사용될 수 있다.

Keywords

References

  1. Interface specification IS-GPS-200: Navstar GPS Space Segment/Navigation User Segment Interfaces, Global Positioning System Directorate, 2019.
  2. J. B. Y. Tsui, Fundamentals of Global positioning System Receivers -A Software Approach, John Wiley & Sons Inc, 2005. DOI: 10.1002/0471200549
  3. Kai borre, A software Defined GPS and Galieo receiver -A single frequency approach, Birkhauser, 2007. DOI: 10.1007/978-0-8176-4540-3
  4. Kaplan, Elliott, and Christopher Hegarty. Understanding GPS: principles and applications. Artech house, 2005. DOI: 10.1017/S0373463300023730
  5. Kovar, P., P. Kacmarik, and F. Vejrazka. "Interoperable GPS, GLONASS and Galileo software receiver," IEEE Aerospace and Electronic Systems Magazine, Vol26, No.4, 2011. DOI: 10.1109/MAES.2011.5763340
  6. Shivaramaiah, Nagaraj C., and Andrew G. Dempster. "On the baseband hardware complexity of modernized GNSS receivers," IEEE International Symposium on Circuits and Systems, 2010. DOI: 10.1109/ISCAS.2010.5537816
  7. Yuying Zheng, "A software-based frequency domain parallel acquisition algorithm for GPS signal," International Conference on Anti-Counterfeiting, Security and Identification, 2010. DOI: 10.1109/ICASID.2010.5551340
  8. Lin, W. H., et al. "Acquisition of GPS software receiver using split-radix FFT," IEEE International Conference on Systems, Man and Cybernetics, 2006. DOI: 10.1109/ICSMC.2006.384873
  9. Patel, Vandana. "Reduced-size FFT correlation techniques for GPS signal acquisition." Int. J. Comput. 2011.
  10. Ahamed, Shaik Fayaz, et al. "Fast acquisition of GPS signal using Radix-2 and Radix-4 FFT algorithms," IEEE 6th International Conference on Advanced Computing, 2016. DOI: 10.1109/IACC.2016.130
  11. Rao, M. Venu Gopala, and D. Venkata Ratnam. "Faster acquisition technique for software-defined GPS receivers," Defence Science Journal, 2015. DOI: https://doi.org/10.14429/dsj.65.5579