• Aerospace Engineering and Technology
• /
• v.13 no.2
• /
• pp.73-79
• /
• 2014

During developing cubesat flight software, Communication test between cubesat and ground station is needed. For this, we have constructed indoor ground station without outdoor antenna for decreasing total cost and time. In this time, if output power of ground station is high, it will affect for cubesat transceiver to be fail. For solving this problem, ground station must be designed for output power of it to be lower than input power of cubesat satellite, and it must be verified. In this paper, first, we describe cubesat indoor ground station using UHF and VHF. Second, we describe output power decreasing test for indoor operation of ground station by attaching attenuators in the end of the output connector.

• Journal of Aerospace System Engineering
• /
• v.16 no.6
• /
• pp.81-89
• /
• 2022

This study measured the radio environment of 10 domestic institutions with CubeSat ground stations for 24 hours in three frequency bands (VHF/UHF/S-band) allocated by the International Telecommunication Union (ITU). The impact of the RF environment around the ground stations on CubeSat downlink frequencies was analysed and compared with acceptable interference noise requirements from the CubeSat RF link. The findings indicate that not only the selection of downlink frequency but also the configuration of RF communication link design and ground station system of CubeSat should consider the S-band RF environment around the ground station due to the presence of several wireless devices.

• Journal of Aerospace System Engineering
• /
• v.17 no.4
• /
• pp.104-109
• /
• 2023

The Cube Satellite Contest has been held six times as of August 2023, and a total of 21 teams have been selected. Fifteen Cube Satellites selected in previous contests were successfully launched and entered into low-Earth orbit. The six Cube Satellites selected in the sixth contest in 2022 are currently undergoing detailed design, and are scheduled to be launched in 2025 using a Korean launch vehicle. In this study, we analyzed the initial operation reports submitted by the selected teams of the Cube Satellite Contest in 2012, 2013, 2015, 2017, and 2019 to assess mission performance and identify causes of mission failure. Based on the submitted reports, an improvement scheme to enhance mission success for future Cube Satellites is proposed.

• Journal of Space Technology and Applications
• /
• v.4 no.2
• /
• pp.87-104
• /
• 2024

CubeSats are being utilized in various fields such as Earth observation, space exploration, and verification of space science and technology due to their low cost, short development period, enhanced mission-oriented performance, and ability to perform various missions through constellation and formation flights. Recently, as the availability of CubeSats has increased and their application areas have expanded, the demand for high-speed transmission of large amounts of data obtained by CubeSats has increased unprecedentedly. Laser-based free space optical communication technology is capable of transmitting large amounts of data at high speeds compared to the existing radio communication methods, and provides various advantages such as use of unlicensed spectrum, low cost, low power, high security characteristics, and of use a small communication platform. For this reason, it is suitable as a high-performance communication technology to support CubeSat missions. In this paper, we will present the core components and characteristics of CubeSat-based space laser communication system, and recent research trends, as well as representative technology development results.

• Journal of Space Technology and Applications
• /
• v.4 no.2
• /
• pp.137-152
• /
• 2024

Currently, investigations in microgravity environments are carried out in a variety of applications, including drop towers, where experiments can be performed for short periods of time, and space stations, where time is not limited. However, producing a microgravity environment for long-term scientific research requires huge development expenditures and efforts. As a result, if the microgravity experiment is carried out on a cubesat, the variety of scientific studies will likely increase even more due to its low cost. The Korea Microgravity Science Laboratory (KMSL) cubesat, which has these features, is a satellite that has carried out microgravity science missions. On March 22, 2021, the KMSL satellite was launched by a Soyuz2.1a from Baikonur in Kazakhstan and operated normally for nearly two months. This article presents results and lessons gained for successfully completing science missions in microgravity based on the KMSL satellite's operational experience.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.7
• /
• pp.586-593
• /
• 2014

The CNUSAIL-1 project aims to develop and operate a 3U-sized cube satellite with solar sail mechanism. The primary mission is to successfully deploy the solar sail in a low earth orbit, and the secondary mission is to collect the scientific data for the effect of the solar sail deployment and operation on orbit maneuver and attitude change of the cube satellite. For this, the bus system will collect and transmit the dynamic data of the satellite and the visual images of the solar sail operation. This paper describes solar sail mission and conceptual design of CNUSAIL-1. The actuation/operation of the solar sail and the bus system are preliminarily designed in terms of attitude control system, communication system, electrical power system, command and data handling system, structure and thermal control system is designed.

• Journal of Aerospace System Engineering
• /
• v.6 no.4
• /
• pp.34-39
• /
• 2012

CubeSats classified as pico-class satellite require a ground station to track the satellite, transmit a command, and receive an on-orbit data such as SOH (State-of-Health) and mission data according to the operation plan. For this, ground station system has to be properly designed to perform a communication to with the satellite with enough up- and down-link budgets. In this study, a conceptual design of the ground station has been performed for the CubeSat named as STEP Cube Lab. (Cube Laboratory for Space Technology Experimental Project). The paper includes a ground station hardware interface design, link budget analysis and a ground station software realization. In addition, the operation plan of the ground station has been established considering the STEP Cube Lab. mission requirements.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.44 no.11
• /
• pp.997-1005
• /
• 2016

Flight software plays an important role in operating satellites, such as processing commands from ground station, controlling satellites and processing mission data. Reliability is the most important thing in flight software and many verifications and tests are needed for assuring it. this causes an increase of cost and period of development. So NASA has developed a reusable flight software platform to apply to their satellite projects. The CFS(Core Flight System) is the very result. We are developing our flight software for a nano-satellite based on NASA CFS. We have tested core services and functions provided in CFS and we have designed and implemented flight software based on these.

• Journal of Aerospace System Engineering
• /
• v.9 no.4
• /
• pp.37-42
• /
• 2015

The CubeSats is classified as a pico-class satellite which requires a ground station to track the satellite, transmit commands, and receive an on-orbit data such as SOH (State-of-Health) and mission data according to the operation plan. In order to this, the ground station system has to be properly designed to perform a communication to with the satellite with enough up- and down-link budgets. In this study, a conceptual design of the ground station has been performed for the CubeSat named as STEP Cube Lab. (Cube Laboratory for Space Technology Experimental Project). The paper includes a ground station hardware interface design, a link budget analysis and a ground station software realization. In addition, the operation plan of the ground station has been established considering the STEP Cube Lab. mission requirements.