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Development of Near Real Time GNSS Precipitable Water Vapor System Using Precise Point Positioning

정밀절대측위를 이용한 준실시간 GNSS 가강수량 시스템 개발

  • Received : 2017.10.31
  • Accepted : 2017.12.15
  • Published : 2017.12.31

Abstract

GNSS PWV (Precipitable Water Vapor) is recognized as an important factor for weather forecasts of typhoons and heavy rainfall. Domestic and foreign research have been published that improve weather forecasts using GNSS PWV as initial input data to NWP (Numerical Weather Prediction) model. For rainfall-related weather forecasts, PWV should be provided in real time or NRT (Near-Real Time) and the accuracy and integrity should be maintained. In this paper, the development process of NRT GNSS PWV system using PPP (Precise Point Positioning). To this end, we optimized the variables related to tropospheric delay estimation of PPP. For the analysis of the PPP NRT PWV system, we compared the PWV precision of RP (Relative Positioning) and PPP. As a result, the accuracy of PPP was lower than that of RP, but good results were obtained in the PWV data integrity. Future research is needed to improve the precision of PWV in the PPP method.

GNSS 가강수량은 태풍이나 집중호우의 일기예보를 위한 중요한 요소로 인식되고 있으며, 가강수량을 수치예보 모델에 초기 입력값으로 적용하여 일기예보가 향상되는 연구가 국내${\cdot}$외로 발표되고 있다. 호우 관련 일기예보를 위해서는 가강수량이 실시간 또는 준실시간으로 제공되어야 하며 가강수량 자료의 정밀함과 무결성이 유지되어야 한다. 본 논문에서는 정밀절대측위를 이용한 준실시간 가강수량 산출 시스템 개발 과정에 대해 제시하였다. 이를 위하여 정밀절대측위의 대류권 지연 추정과 관련된 변수를 최적화하고 준실시간 GNSS 가강수량 시스템을 개발하였다. 시스템의 분석을 위해 정밀절대측위와 상대측위의 준실시간 가강수량 정밀도를 비교하였다. 비교결과 정밀절대 측위의 가강수량 정밀도가 상대측위 보다 낮게 산출되었지만 자료의 무결성 부분에서는 좋은 결과가 도출되었다. 향후에는 정밀절대측위 방식의 가강수량 정밀도를 높이는 연구가 필요할 것이다.

Keywords

References

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