• Title/Summary/Keyword: RALT, Radar Altimeter

Search Result 3, Processing Time 0.018 seconds

Improvement of Abnormal Altitude Display of Radar Altimeter by Using Attenuation of Received Interference (수신 간섭의 신호 감쇠를 통한 전파고도계의 비정상 고도 시현 개선)

  • Kwon, Jung-Hyuk;Oh, Seung-Hyun;Seo, Byung-Il;Lee, Wang-Sang
    • Journal of Aerospace System Engineering
    • /
    • v.16 no.2
    • /
    • pp.39-48
    • /
    • 2022
  • The purpose of this paper was to study how to improve the occurrence of abnormal altitude values of radio altimeter, due to RF interference signals during the flight of aircraft. In flight missions, since it performs a roll-out after several high maneuvers, accurate altitude must be displayed to effectively perform flight missions. Thus, a root cause analysis and trouble shooting were performed for the display of abnormal altitude values of radar altimeters, and a method of reducing RF interference signals by installing an attenuator was examined. Additionally, the verification results for the improvements are also described.

Analysis of Optimum Antenna Placement Considering Interference Between Airborne Antennas Mounted on UAV (무인항공기 탑재 안테나 간 간섭을 고려한 안테나 최적 위치 분석)

  • Choi, Jaewon;Kim, Jihoon
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.52 no.6
    • /
    • pp.32-40
    • /
    • 2015
  • In this paper, the optimum antenna placement is analyzed by considering the interference between airborne antennas mounted on the unmanned aerial vehicle(UAV). The analysis is implemented by selecting the antennas that the distance and operational frequency band between airborne antennas is close to each other among the omni-directional antennas. The analyzed antennas are the control datalink, TCAS(Traffic Collision & Avoidance System), IFF(Identification Friend or Foe), GPS(Global Positioning System), and RALT(Radar ALTimeter) antennas. There are three steps for the optimum antenna placement analysis. The first step is selecting the antenna position having the optimum properties by monitoring the variation of radiation pattern and return loss by the fuselage of UAV after selecting the initial antenna position considering the antenna use, type, and radiation pattern. The second one is analyzing the interference strength between airborne antennas considering the coupling between airborne antennas, spurious of transmitting antenna, and minimum receiving level of receiving antenna. In case of generating the interference, the antenna position without interference is selected by analyzing the minimum separation distance without interference. The last one is confirming the measure to reject the frequency interference by the frequency separation analysis between airborne antennas in case that the intereference is not rejected by the additional distance separation between airborne antennas. This analysis procedure can be efficiently used to select the optimum antenna placement without interference by predicting the interference between airborne antennas in the development stage.

A Study on Reliability Improvement of RALT for KUH through Fault Analysis (한국형기동헬기 레이더고도계의 결함분석을 통한 신뢰성 향상에 관한 연구)

  • Jun, Byung Kyu;Kim, Young Mok;Chang, Joong Jin;Kim, Chang Young;Hwang, Gil Won
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.42 no.5
    • /
    • pp.406-414
    • /
    • 2014
  • In this paper, it is introduced characteristics of FMCW-type Radar Altimeter for KUH, and its defects occurred during ground/flight test in initial product phase. In addition, it is also described 'data/control flow model' based fault analysis results of S/W and processes of verifying improvement design through flight test as well as aircraft system integration test called MEP SIL. As a result of design improvement and verification, it is validated that settling the defects and improving not only safety but also capability of the KUH.