라디오존데 관측자료 기반 저고도 대기굴절 특성과 가시선 변화 분석

박명훈^* ; 김정 ; 이성균 ; 고진용 ; 장재덕

LIG 디펜스&에어로스페이스 M&S팀 수석연구원

Analysis of Low-Altitude Atmospheric Refractivity Characteristics and Line-of-Sight Variations Based on Radiosonde Observations

Myunghoon Park^* ; Jeong Kim ; Sungkyun Lee ; Jinyong Go ; Jaedeok Jang

Chief research engineer, M&S Team, LIG Defense&Aerospace

Correspondence to: *Myunghoon Park 333 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do, 13488, Republic of Korea Tel: +82-31-5179-7267 Fax: +82-31-5179-7086 E-mail: pmh604god@gmail.com

초록

본 연구에서는 기상청 라디오존데 관측자료를 이용하여 함정 탑재 레이다의 저고도 전파환경을 분석하고, 대기굴절 특성이 기하학적 가시선(LOS)에 미치는 영향을 정량적으로 평가하였다. 기존의 0 km–1 km 평균층 대신 레이다 운용환경을 고려한 20 m–200 m 인접층을 분석 대상으로 설정하여 굴절도 기울기, k-factor 및 LOS 변화를 산출하였다. 분석 결과, 정상굴절이 가장 높은 발생 비율을 보였으며, 여름철에는 초굴절 및 덕트 발생 증가와 함께 k-factor 증가 및 LOS 증가 경향이 뚜렷하게 나타났다. 또한 동일한 관측자료라도 분석 고도층에 따라 굴절환경과 LOS 변화 특성이 서로 다르게 나타나 기존 0 km–1 km 대표층만으로는 저고도 레이다 운용환경을 충분히 반영하기 어려움을 확인하였다.

Abstract

The aim of this study was to quantitatively investigate the effects of atmospheric refractivity on the low-altitude propagation environment of shipborne radars using Korea Meteorological Administration radiosonde observations. Instead of the conventional 0–1 km boundary layer, a radar-adjacent layer of 20–200 m was analyzed to estimate the refractivity gradient, effective Earth radius factor (k-factor), and geometric line-of-sight (LOS) variation. The results show that normal refraction was the dominant propagation condition, and summer exhibited increased super-refraction and ducting, accompanied by higher k-factors and extended LOS distances. Furthermore, noticeable differences were observed between the conventional boundary-layer analysis and the radar-adjacent layer analysis, indicating that the conventional approach does not fully represent the propagation environment experienced by low-altitude shipborne radars.

Keywords:

Atmospheric Refractivity, Radiosonde, Radio Wave Propagation, Line-of-Sight, Atmospheric Ducting

키워드:

대기 굴절도, 라디오존데, 전파 전파, 가시선, 대기 덕트

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