Journal of the Korean Society for Aeronautical & Space Sciences (한국항공우주학회지)

The Korean Society for Aeronautical and Space Sciences (한국항공우주학회)
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Radio Frequency Interference on the GNSS Receiver due to S-band Signals

S 대역 신호에 의한 위성항법수신기의 RF 신호간섭

  • Kwon, Byung-Moon (KSLV-II R&D Head Office, Korea Aerospace Research Institute) ;
  • Shin, Yong-Sul (KSLV-II R&D Head Office, Korea Aerospace Research Institute) ;
  • Ma, Keun-Su (KSLV-II R&D Head Office, Korea Aerospace Research Institute) ;
  • Ju, Jeong-Gab (Alternative Navigation Division, Navcours Co., Ltd.) ;
  • Ji, Ki-Man (KSLV-II R&D Head Office, Korea Aerospace Research Institute)
  • Received : 2019.03.29
  • Accepted : 2019.04.25
  • Published : 2019.05.01
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Abstract

This paper describes the RF(Radio Frequency) interference on the GNSS receiver due to the S-band signals transmitted from the transmitters in the Test Launch Vehicle, and analyzes the cause of the RF interference. Due to the S-band signals that have relatively high power levels compared with GNSS signals, an LNA(Low Noise Amplifier) in the active GNSS antenna was saturated, and the intermodulation signal within GNSS in-bands was produced in the LNA whenever two S-band signals were received from the GNSS antenna. For these reasons, the C/N0 of the satellite signals in the GNSS receiver was attenuated severely. The design of the LNA was changed in order to protect the RF interference due to the S-band signals and the suppression capability of the RF interference was confirmed in the new LNA through the comparison of the old LNA.

본 논문은 시험발사체에 탑재된 송신기에서 송신되는 S 대역 신호에 의해 위성항법수신기에서 나타난 RF 신호간섭을 설명하고, 그 원인을 분석한다. 능동형 위성항법안테나의 LNA는 항법위성 신호와 비교하여 상대적으로 신호세기가 매우 높은 S 대역 신호에 의해 포화되었으며, 2개의 S 대역 신호가 위성항법안테나에 수신될 때마다 GNSS 대역에 해당하는 상호변조신호가 LNA에서 발생하였다. 이러한 현상으로 인해 위성항법수신기에서 계산된 항법위성신호의 C/N0가 크게 감쇄하였다. S 대역 신호에 의한 RF 신호간섭을 차단하기 위하여 위성항법안테나 LNA의 설계변경을 수행하였고, 설계변경 전 후의 LNA에 대해 수행한 비교시험을 통하여 설계변경된 LNA에서 S 대역 신호에 의한 RF 신호감쇄 현상이 억제될 수 있음을 확인하였다.

Keywords

References

  1. Kwon, B. M., Moon, J. H., Shin, Y. S., Choi, H. D., and Cho, G. R., "Development of a GPS receiver system for satellite launch vehicles," Journal of the Korean Society for Aeronautical and Space Sciences, Vol. 36, No. 9, 2008, pp.929-937. https://doi.org/10.5139/JKSAS.2008.36.9.929
  2. Kwon, B. M., Moon, J. H., Shin, Y. S, and Choi, H. D., "A conceptual design of the next generation GNSS receiver for satellite launch vehicles," The 11th Space Launch Vehicle Technology Symposium, 2010.
  3. Leung, J., Schipper, G., Tseng, G. T., and Wildhagen, P., "GPS applications to launch vehicles," Proceedings of 51st ION Annual Meeting, Jun. 1995, pp. 293-302.
  4. Shin, Y. S., Kwon, B. M., and Ma, K. S., "The design of the GNSS antenna preventing LNA saturation by S band signal," 2018 KSAS Fall Conference, 2018.
  5. Shin, Y. S., Kwon, B. M., Moon, J. H., and Choi, H. D., "GNSS antennas for space launch vehicles," 2012 KGS Conference, 2012.
  6. Landry, R. J., and Renard, A., "Analysis of potential interference sources and assessment of present solutions for GPS/GNSS receivers," 4th Saint-Petersburg on INS, 1997.
  7. Lomer, M., Fulga, S., and Gammel, P., "GNSS on the go: Sensitivity and performance in receiver design," Inside GNSS, Spring 2008, 46-51.
  8. Wildemeersch, M., and Fortuny-Guasch, J., "Radio frequency interference impact assessment on Global Navigation Satellites Systems," Institute for the Protection and Security of the Citizen, 2010.
  9. Law, E. Kingery, R., and Cramer, D., "Investigation of telemetry and GPS compatibility," International Telemetering Conference, 2017.
  10. Kwon, B. M., Shin, Y. S., and Ma, K. S., "Signal interference of a GNSS receiver for the test launch vehicle," 2017 IPNT Conference, 2017.
  11. Kwon, B. M., Moon, J. H., Shin, Y. S., Choi, H. D., and Cho, G. R., "Operation of the GPS receiver system for KSLV-I on the launch site at Naro Space Center," Journal of the Korean Society for Aeronautical and Space Sciences, Vol. 38, No. 7, 2011, pp.737-745. https://doi.org/10.5139/JKSAS.2010.38.7.737
  12. Kwon, B. M., Moon, J. H., Shin, Y. S., and Choi, H. D., "GPS interference on launch pad at Naro Space Center," The 12th Space Launch Vehicle Technology Symposium, 2013, pp. 45-50.
  13. Kwon, B. M., Moon, J. H., Shin, Y. S., and Choi, H. D., "A solution for the GPS interference on launch pad of KSLV-I using a filter," 2013 KGS Conference, 2013.
  14. Kwon, B. M., Shin, Y. S., Moon, J. H., and Min, B. J., "Specifications of the LNA filter in a GNSS antenna for KSLV-II," The 14th Space Launch Vehicle Technology Symposium, 2015.
  15. "Recommendation ITU-R SM.2021: Production and mitigation of intermodulation products in the transmitter," Radiocommunication Sector of International Telecommunication Union, 2000.
  16. "Recommendation ITU-R SM.1446: Definition and measurement of intermodulation products in transmitter using frequency, phase, or complex modulation techniques," Radiocommunication Sector of International Telecommunication Union, 2011.
  17. Rhodes, C., "Intermodulation effects: Another perspective on LightSquared interference to GPS," Inside GNSS, Jul./Aug. 2011, pp.20-24.
  18. Orban, D., and Eyerman, T., "GPS antenna LNA", www.vicmyers.com/wp-content/uploads/orbangps.pdf (2019/03/20)
  19. Langley, R. B., "Innovation: A primer on GPS antennas," GPS World, Jul. 1998, pp.50-54.
  20. "LFCN-1500: Ceramic low pass filter," Mini-Circuits, Rev. H.