• 한국항행학회논문지
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• 제12권1호
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• pp.1-7
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• 2008

전방향표지시설 (VOR : VHF Omni-directional Range)은 1949년 국제민간항공기구(ICAO)에서 국제 항공항법 표준시스템의 하나로 지정한 이후, 각국에서 항공로 구성과 항공기의 이착륙 정보제공에 널리 사용하고 있다. 현재 VOR은 우리나라의 39 대를 포함하여 전 세계적으로 2,000여대가 설치되어 있어 가장 유용하게 활용되고 있는 단거리 항공 항법시스템이나, VHF 반송파를 진폭 및 주파수변조하여 항법정보를 제공하기 때문에 산악지대 등 주변 장애물의 영향을 많이 받아 예상하지 못한 성능 미흡으로 이미 설치한 장비를 다시 옮기는데 따른 비용과 시간이 많이 허비되는 등 사회적인 문제를 야기하기도 한다. 이 논문에서는 원거리 장애물이 VOR의 성능에 어느 정도 영향을 미치는 지를 계측기 등을 장착한 항공기를 이용하여 10개 VOR의 24개 장애물에 대하여 측정 및 분석하고, 이를 VOR의 설치장소 결정에 활용할 수 있도록 하여 성능 미흡으로 설치된 장비를 이전하는 등의 문제점을 해소하는데 도움을 주고자 한다.

• 한국항행학회논문지
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• 제8권2호
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• pp.144-154
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• 2004

본 논문에서는 4세대 이동통신시스템의 핵심 기술인 Space-Time Block Code (STBC)를 OFDM 시스템에 적용하고 주파수 선택적 레일라이 페이딩 환경에서 각 방식의 성능을 시뮬레이션을 통해서 비교, 분석한다. 먼저 주요 STBC 방식들의 신호 모델과 각 방식별로 복조과정을 유도한다. 또한, 이동통신 환경을 고려하여 OFDM 시스템 파라메타를 설정하고 2bps/Hz에서 4bps/Hz 까지의 전송율에 대해 STBC 방식별로 적절한 변조방식을 설정하여 각각의 전송속도에 대해 STBC-OFDM 방식들의 성능을 컴퓨터 시뮬레이션을 통해 비교, 분석한다. 이 밖에, 각 STBC-OFDM 방식들이 동일한 변조방식을 사용할 경우에 대해서도 성능을 비교, 분석한다.

• Transactions on Control, Automation and Systems Engineering
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• 제4권2호
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• pp.114-123
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• 2002

Called VISTA (Variable-stability In-flight Simulator Test Aircraft), the one-of-a-kind NF-l6D has a simulation system that can mimic several aircraft. Though housed in an F-l6 Fighting Falcon airframe, VISTA can also act like the F-15 Eagle or the Navy's F-14 Tomcat. More importantly, such flexibility allows for improved training and consolidation of some sorties. Consequently USAF Test Pilot School students will have an opportunity to learn how to test future integrated cockpits. In this paper we will use the multiple model adaptive estimation (MMAE) and the multiple model adaptive controller (MMAC) techniques to model the aircraft's flight control system containing the longitudinal and lateral-directional axes. Single and dual actuator and sensor failures will also be included in the simulation. White Gaussian noise will be included to simulate the effects of atmospheric disturbances.

• Journal of Positioning, Navigation, and Timing
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• 제9권2호
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• pp.125-129
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• 2020

In this paper, Zero velocity UPdaTe (ZUPT) is implemented on the navigation system of Remotely Piloted Aircraft for GNSS denied environment. RPA's navigation system suffers from lack or loss of satellite signal while maintenance or ground test inside a hangar. Although some of the hangars install GPS repeaters for indoor tests, the anti-jamming equipment with array antenna blocks the repeater signal regarding them as hostile jamming signal. With ZUPT, an aircraft navigation system can be tested free from the divergence of navigation solution without line-of-sight satellites. The designed ZUPT aided centralized Kalman Filter is implemented on the Embedded GPS&INS and simulated with Captive Flight Test data. The simulation result shows stable navigation solution without GNSS updates.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2000년도 제14회 학술강연논문집
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• pp.6-6
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• 2000

On-orbit thermal behavior of KOMPSAT (Korea Multi-purpose Satellite) propulsion system employing hydrazine (N$_2$H$_4$) liquid monopropellant is addressed. Thermal control performance to prevent propellant freezing in spacecraft-operational orbit was verified by flight telemetry data obtained during LEOP (Launch and Early Operation Phase). Results are depicted in terms of temperature history during several orbits selected and are compared with acceptable temperature ranges of system components. Cyclic behavior of temperature is reduced into duty cycles of the avionics heaters and subsequently converted into the electrical power required to keep away from propellant freezing. Temperature of each component which was achieved under on-ground thermal-balanced condition of spacecraft, is presented for comparison with the flight data, additionally.

• 한국항행학회논문지
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• 제16권3호
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• pp.449-454
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• 2012

최근 유비쿼터스 컴퓨팅 기술의 발전함에 따라 센서기반 시스템이 IT 업계의 큰 이슈로 떠오르고 있다. 센서기반시스템을 응용한 스마트 기상 측정 시스템은 기상관측의 중요 인자인 온도를 위치와 고도에 구애받지 않고 실시간으로 측정할 수 있다. 스마트 기상 측정 시스템은 GPS의 위치정보를 송신하는 제어부와 PC의 무선 수신부로 구성되었다. 제어부는 측정기구 본체로서 ATmega2560을 프로세서로 사용하여 온도센서와 GPS를 제어하고, 측정된 정보는 RF 모듈을 통해서 수신부에서 송신부인 PC로 보내서 데이터를 처리할 수 있도록 하였다.

• 시스템엔지니어링학술지
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• 제2권1호
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• pp.18-23
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• 2006

The purpose of this study and report is to provide, to the MND, an independent cost analysis of modernizing software of F-16 fighter fleets to support the use of several weapon system options, including JDAM, AIM-9X and HARM Targeting System etc. The study analyzed each options with software sizing, software cost, enabling hardware cost, flight test cost, system engineering cost, and 3 strategies. And the study proposed and analyzed some alternative strategies: strategy1 is to modernize software only within existing electronic processing capability; strategy2 is a full upgrade of weapons avionics with plug compatible electronics; strategy3 is an approach defined to mirror the USAF Common Configuration Implementation Approach (CCIP). The recommended alternative is strategy2.

• Journal of Information Processing Systems
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• 제15권6호
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• pp.1462-1471
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• 2019

Real-time embedded systems have become pervasive in general industry. They also began to be applied in such domains as avionics, automotive, aerospace, healthcare, and industrial Internet. However, the system failure of such domains could result in catastrophic consequences. Runtime software testing is required in such domains that demands very high accuracy. Traditional runtime software testing based on handwork is very inefficient and time consuming. Hence, test automation methodologies in runtime is demanding. In this paper, we introduce a software testing system that translates a real-time software into a monitorable real-time software. The monitorable real-time software means the software provides the monitoring information in runtime. The monitoring target are time constraints of the input real-time software. We anticipate that our system lessens the burden of runtime software testing.

• International Journal of Aerospace System Engineering
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• 제2권2호
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• pp.87-91
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• 2015

KT-1P for the Peru Air Force will be used as a utility aircraft with upgraded avionics equipment and arming capability based on KT-1 and KA-1. KT-1P should be shown for compatibility of new store loading configurations loaded with dispenser, bomb, and rocket based on aircraft-store compatibility test and evaluation procedures before KT-1P is operated as a light attack aircraft. The weapon system ground test for installation and flight test for envelope expansion including store separation are described in this paper, which was performed referring 'seek eagle program' under MIL-HDBK-1763 and MIL-HDBK-244A.

• 한국군사과학기술학회지
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• 제5권2호
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• pp.123-131
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• 2002

ASC(Avionics System Computer) was developed to control weapon delivery and navigation sensors, and to perform man-machine interface with pilots for XKO-1 aircraft. The data communications between ASC and UFC(Up Front Controller), DC(Data Concentrator) were implemented by RS422 serial data bus. Also, SCIL(Standard Computer Interface Library) was designed to facilitate control and management of the computer hardware resources and is embedded in the ASC. These structures have a merit of noise immunity and a reduction of wire harness for signal lines, and enable OFP(Operational Flight Program) programmers to use the SCIL easily without knowing hardware details. Manufactured system was on installed on XKO-1, and peformed for BIT(Built In Test) and interface test with UFC and DC. The test results show that it meets the system requirements.