Altitude Error Analysis of Helicopter-Borne FMCW Radar Altimeter

헬기 탑재 레이다 고도계 신호 수집 및 오차 분석

  • 정정수 (한국항공대학교 항공전자공학과) ;
  • 이호준 (LIG 넥스원) ;
  • 곽영길 (한국항공대학교 항공전자공학과)
  • Received : 2012.01.02
  • Accepted : 2012.01.26
  • Published : 2012.02.29


Helicopter-borne FMCW radar altimeter obtains the altitude information using the beat frequency between the transmitted and reflected signal from the nadir direction. However, the altitude error may exist when the strong echoes are received from the large RCS at the off-nadir direction because of the wide beamwidth of the altimeter antenna. In this paper, in order to investigate the effect of the altitude error due to the large RCS around the off-nadir direction, the reflected signals were measured by using the corner reflectors displaced on the several reference ground positions, and the acquired signals were analyzed and compared in the spectral domain. The analysis results can be used for the improvement of the altitude accuracy in the radar altimeter.


Radar Altimeter;FMCW;Beat Frequency;Radar Cross Section


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