• Journal of Advanced Navigation Technology
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• v.28 no.3
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• pp.278-287
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• 2024

In this paper, telemetry link budget model for small launch vehicle is proposed, and telemetry link budget simulator is implemented. The proposed link budget model consist of geometry model and propagation loss model. The geometry model is calculation of look angle between ground station and small launch vehicle. The propagation loss model consist of free space loss, polarization loss, and de-pointing loss which are appropriate to the small launch vehicle flight environment. The proposed propagation loss model can be calculate propagation loss without complex calculation of propagation environments. The link budget simulator is implemented in MATLAB. The simulator calculate look angle, free space loss, polarization loss parameter, de-pointing loss and received signal level in ground station by using position of ground station, routing of small launch vehicle, 3-D radiation patterns of antennas.

• Aerospace Engineering and Technology
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• v.1 no.2
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• pp.45-50
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• 2002

A conceptual design on the link budget of TC&R RF subsystem which transfers command and telemetry data as RF signal between the ground system and the 2005SAT spacecraft is presented in this paper. In order to perform the analysis of the link budget, we divided the analysis process into two processes, i.e., uplink and downlink process. For the uplink the power flux density at the spacecraft and the margin of the command receiver are calculated. In the case of the downlink the downlink EIRP and the margin of C/ No and Eb / No at the ground station are calculated. Through the uplink performance analysis, the power at the command receiver has well efficient margin, and the margin of C/ No and Eb / No is also fully proper for the downlink case.

• The KIPS Transactions:PartC
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• v.9C no.3
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• pp.439-444
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• 2002

In this paper, we present both the link budget analysis according to system parameters and the cell coverage according to transmitter power and modulation scheme of digital MMDS among the wireless CATV system methods which is bated on the wireless internet service. Also, in this paper, we present C/I and number of subscriber according to splitting cell. In this paper, the cell coverage of which obtain the results according to both transmitter power from 0dBW to -9dBW and modulation scheme of QPSK, 16QAM and 64QAM based on link budget was analysis for system parameter of digital MMDS was able to provide from maximum 134km to minimum 4.3km. Also, in this paper, the number of subscriber of which obtain the results according to polarization wave, frequency of frequency reuse and C/I in 4. 6 and 8 sectors was able to provide from maximum 5,200DSI to minimum 1,300DSI.

• Aerospace Engineering and Technology
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• v.13 no.1
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• pp.108-119
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• 2014

In this paper, through the example of international lunar exploration mission the equipment was to investigate, and the amount of data transferred per day were identified. Data storage and the data transfer rate (8.4Mbps less) for the satisfaction of the value within the range of available S and X bands was confirmed by using the communication link budget. The result is to define the range of the sensor information can be obtained, as well as from the values of the parameters calculated for the transmission communication systems will be able to define the specifications.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.178.2-178.2
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• 2012

정지궤도위성은 발사체에서 위성이 분리된 이후 천이궤도로부터 원하는 목표궤도로 궤도전이를 해야 한다. 또한 임무기간동안 궤도상에서 다양한 교란을 겪게 되며 이로 인해 시간이 증가함에 따라 위성의 위치가 변화하게 된다. 정지궤도위성은 이러한 궤도전이 및 궤도상 위치변화를 제어하기 위한 추진시스템을 장착하고 임무기간에 걸쳐 요구되는 추진제를 탑재해야 한다. 위성의 설계 초기에는 추정되는 위성의 건조질량을 기반으로 하여 궤도전이와 궤도상 임무에 필요로 하는 추진제 버짓을 계산하고 이를 토대로 하여 위성 시스템 설계를 진행한다. 또한 발사체별로 발사체의 성능과 발사장에 따라 근지점고도와 발사 경사각이 모두 상이하므로 발사체가 정해지지 않은 상태에서 발사체별 추진제 버짓을 계산, 비교하고 추진 시스템의 탱크가 이를 모두 수용할 수 있는지 분석하는 것이 중요하다. 본 논문에서는 정지궤도복합위성의 추정 건조질량과 임무분석을 통해 주어진 ${\Delta}V$와 각 발사체별 궤도전이에 필요한 ${\Delta}V$를 바탕으로 하여 발사체별 추진제버짓을 계산하였고 이를 비교검토 하였다. 이후 이러한 기본 자료를 바탕으로 하여 정지궤도복합위성 추진시스템의 추진제 수용가능 여부, 건조질량 증가 여유 등 기본설계를 진행할 수 있다.

• Journal of Advanced Navigation Technology
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• v.23 no.6
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• pp.584-588
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• 2019

Wireless body area network (WBAN) is a networking technology that enables early detection of abnormal health conditions, real-time medical monitoring, and telemedicine support systems. The internet of things (IoT) for healthcare, which has become an issue recently, is one of the most promising areas for improving the quality of human life. It must meet the high QoS requirements of the medical communication system like any other communication system. Therefore, the bit error rate (BER) threshold was chosen to accommodate the QoS requirements of the WBAN communication system. In this paper, we calculated BER performance of WBAN channel using IR-UWB PPM modulation and analyzed link budget and system margin of WBAN according to various system parameters.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.9
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• pp.771-780
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• 2021

The space Debris laser ranging system is called to be a definite type of satellite laser ranging system that measures the distance to satellites. It is a system that performs POD (Precise Orbit Determination) by measuring time of flight by firing a laser. Distance precision can be measured in mm-level units, and it is the most precise system among existing systems. Currently, KASI has built SLR in Sejong and Geochang, and utilized SLR data to verify the precise orbits of the STSAT-2C and KOMASAT-5. In recent years, due to the fall or collision of space debris, its satellites have been threatened, and in terms of security, laser tracking of space objects is receiving great interest in order to protect their own space assets and protect the safety of the people. In this paper, a 1.5m-class main mirror was applied for the system design of a multipurpose laser tracking system that considers satellite laser ranging and space object laser tracking. System preliminary performance analysis was performed based on Link Budget analysis considering specifications of major components.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.7
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• pp.891-897
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• 2020

A flight termination system, which consists of ground and vehicle systems, forcibly terminates flight if it is deemed dangerous. In order to accomplish this, the system should maintain the link reliability above a certain level throughout the whole flight. However, the national proving ground for guided missiles could not fully meet that condition because of the gradually improving performance criteria. In this paper, we have analyzed the link budget for the flight termination system. Furthermore, we have designed and developed an emergency destruction command transmitter system, which is a ground system of the flight termination system, to provide the necessary link margin. Afterwards, we measured the received signal strength at the vehicle system and compared it with that of the existing transmitter system. We hereby confirmed that the link reliability of the flight termination system improved.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.12
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• pp.1027-1035
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• 2021

We presents a design of 3U cubesat MIMAN (Monochrome imaging for monitoring aerosol by nano-satellite) for aerosol monitoring mission with high spatial resolution. The main objective of MIMAN mission is to take images of aerosols around Korea and to provide auxiliary data for GK 2B cloud masking. For this mission, we derived mission requirements and constraints for the MIMAN mission. We designed the mission architecture and concept of operations. To reduce risk factors in space operation, we considered the safety of the communication. In every operation modes, UHF communication is available so that the cubesat can operate based on the ground commands. So, we can handle every problem at the ground station during mission operations. Based on the mission and concept of operations, we confirmed that the system design satisfied the system requirements. We designed the system interface considering data flow of each hardware, and evaluated the safety of the system with system budget analysis.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.11
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• pp.1574-1580
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• 2021

This paper designs and presents the results of an air network simulation radio transmission link applied with a multi-beam active phase array antenna simulator in a testbed system for verifying an air network currently underway as a technology development task. Using the Ku band, the Radio transmission link was designed in consideration of the link budget to satisfy the requirements for the system being developed. Considering short-distance links and long-distance links, the required EIRP and G/T performance scales of multi-beam repeaters and mission planes were applied to confirm the minimum and maximum link margins based on Eb/No. In this Radio Transmission Link design, the application analysis results such as rainfall availability are used to effectively establish standards when selecting the operating radius of the multi-beam relay system and related system standards.