DOI QR코드

DOI QR Code

저궤도 위성 간 X-대역 하향링크에서의 간섭 영향성 분석

Interference Analysis Between LEO Satellites for X-band Downlink

  • 투고 : 2021.02.24
  • 심사 : 2021.04.16
  • 발행 : 2021.06.01

초록

지구 관측위성의 데이터를 지상으로 전송하기 위해 활용되는 X-대역 주파수는 한정적이므로, 여러 위성들이 해당 동일 대역을 공유하는 방식으로 활용한다. 복수의 위성이 유사 주파수 대역을 활용하기 위해서 국제전기통신연합-전파통신부문(International Telecommunication Union - Radiocommunication; ITU-R)에서는 송신 대역 내 전력속밀도(Power Flux Density; PFD) 제한 조건이 있고, 이를 통해 위성 간 간섭 영향성을 극복하고 있다. 하지만 이러한 규정 하에서도 복수의 위성이 비교적 근접한 지상국에 접속하는 경우 간섭 영향성의 분석이 수행될 필요가 있다. 본 논문에서는 한반도 내에 임의 배치된 두 개의 지상국을 기준으로, 서로 다른 궤도를 따르는 두 개의 저궤도 위성에 각각 접속하여 통신할 경우에 대해 수신 신호대 간섭+잡음비(Signal to Interference plus Noise Ration; SINR) 기준으로 간섭 영향성 분석을 수행하였다. 간섭 영향성 분석을 통해 PFD 규격을 만족시키는 두 위성이라 하더라도 전체 임무 기간(365일 가정) 내에 간섭은 발생할 수 있으나 영향받는 기간이 짧고 미리 예측할 수 있음을 확인할 수 있었다.

The X-band frequencies for transmitting the data from earth observation satellites are limited, so a number of satellites share the frequency bands. In order for multiple satellites to utilize same or adjacent frequency bands, International Telecommunication Union - Radiocommunication (ITU-R) limits power flux density (PFD), which overcomes the interferences among multiple satellites. However, even under the regulation, the interference effect needs to be analyzed when multiple satellites are connected to communicate with multiple ground stations (GSs) located close to each other. In this paper, the interference effect is analyzed based on signal to interference plus noise ratio (SINR) when two low earth orbit (LEO) satellites operating in different orbits are connected to communicate with randomly located two GSs in Korean peninsula. From the analysis results, it is confirmed that there can be interferences during 365 days operation even if the satellites meet PFD requirement, but the periods under interference effects are short and the interference can be foreseen.

키워드

참고문헌

  1. Recommendation ITU-R SF.358-5, "Maximum permissible values of power flux-density at the surface of the earth produced by satellites in the fixed-satellite service using the same frequency bands above 1 GHz as line-0f-sight radio-relay systems," 5th Ed., Recommendation ITU-R, Genova, 1995, pp. 1~14.
  2. Amin, M. G. and Sun, W., "A Novel Interference Suppression Scheme for Global Navigation Satellite Systems Using Antenna Array," IEEE Journal on Selected Areas in Communication, Vol. 23, No. 5, 2005, pp. 999~1012. https://doi.org/10.1109/JSAC.2005.845404
  3. Lim, Z. H. and Shin, C. S., "Interference Suppression for Satellite Navigation Based on Dual-Polarized Antenna," Information and Control Symposium, October 2020, pp. 315~316.
  4. Vatalaro, F., Corazza, G. E., Caini, C. and Ferrarelli, C., "Analysis of LEO, MEO, and GEO global mobile satellite systems in the presence of interference and fading," IEEE Journal on Selected Areas in Communication, Vol. 13, No. 2, 1995, pp. 291~300. https://doi.org/10.1109/49.345873
  5. An, K., Lin, M., Zhu, W., Huang, Y. and Zheng, G., "Outage Performance of Cognitive Hybrid Satellite-Terrestrial Networks With Interference Constraint," IEEE Transactions on Vehicular Technology, Vol. 65, No. 11, 2016, pp. 9397~9404. https://doi.org/10.1109/TVT.2016.2519893
  6. Henarejos, Z. P., Vazquez, M. A. and Perez-Neira, A. I., "Deep Learning For Experimental Hybrid Terrestrial and Satellite Interference Management," 2019 IEEE 20th International Workshop on Signal Processing Advances in Wireless Communication, July 2019, pp. 1~5.
  7. Kim, H. K., Jo, Y. K., Kim, J. S. and Jo, H. S., "Interference Analysis between Inter-Satellite Service and Submillimeter-wave 5G Mobile Communication Service," Proceeding of Symposium of the Korean Institute of Communications and Information Sciences, June 2017, pp. 524~525.
  8. Kim, B. S., Lee, K. W. and Lee, W. K., "Environmental Impact Analysis of Satellite Communications from Interference," Proceeding of Symposium of the Korean Institute of Communications and Information Sciences, January 2016, pp. 809~810.
  9. Kang, Y. H. and Choi, M. H., "The Analysis on the Interference Effects from Airship of HAPS system to Satellite of GSO system in Ka band," The Journal of the Korean Institute of Communications and Information Sciences, Vol. 29, No. 5B, 2004, pp. 476~481.
  10. Park, H. W. and Jang, Y. S., "Adjacent Satellite Interference Cancellation in Dual-contact Satellite Scenario," Journal of the Institute of Electronics and Information Engineers, Vol. 57, No. 8, 2020, pp. 9~19. https://doi.org/10.5573/ieie.2020.57.8.9
  11. Pitz, W. and Miller, D., "The TerraSAR-X Satellite," IEEE Transactions on Geoscience and Remote Sensing, Vol. 48, No. 2, 2010, pp. 615~622. https://doi.org/10.1109/TGRS.2009.2037432
  12. Bouchal, Z. and Olivik, M., "Non-diffractive vector Bessel beams," Journal of Modern Optics, Vol. 42, No. 8, 1995, pp. 1555~1566. https://doi.org/10.1080/09500349514551361
  13. Recommendation ITU-R P. 618-13, "Propagation data and prediction methods required for the design of earth-space telecommunication systems," 13th Ed., Recommendation ITU-R, Genova, 2017, pp. 1~29.
  14. CCSDS 413.0-G-2, Bandwidth-efficient Modulations: Summary of Definition, Implementation, and Performance, 2nd Issue, GREEN BOOK, Washington DC, 2009, pp. B-4~B-7.