SNUGLITE-I (2017-2019)

Seoul National University GNSS Laboratory Satellite (SNUGLITE)-I Project

• 2U CubeSat mission (Launch: Dec 2018)
• Funded by Korea Aerospace Research Institute (KARI)
• Finalist in the 2015 Korea CubeSat Competition

SNUGLITE-I Mission Concept

System

• 2U CubeSat
• Main payloads: L1/L2C GPS receiver x2
• Sub payloads: 3-axis fluxgate magnetometer w/ deployable boom
• Mass: 1.9 kg
• Orbit: SSO 575km (LTDN 10h30m)​

Frequency:

• UHF (437.275MHz)
  • downlink : beacon, command-return
  • uplink : tele-command
• S-band (2405MHz)
  • downlink : housekeeping data, mission data

Beacon Structure

• downlink frequency: 437.275MHz
• modulation: GMSK
• baudrate: 9600bps
• protocol : AX.25 and CSP (cubesat space protocol)

message structure

• Payload data is covered by 4-byte header of CSP (https://en.wikipedia.org/wiki/Cubesat_Space_Protocol).
• 32 byte Reed-Solomon (223, 255) block code is applied from CSP header to the end of payload data and added to the end of payload data.
• AX.25 protocol is also used with the header and beginning and ending of “0xC0”.
• There are two types of payload data: simple beacon (length: 45 byte) and full beacon (162 byte).
• In stand-by operation mode, the period of simple beacon and full beacon is 10 sec and 30 sec, respectively. And full beacon is prior than simple beacon.
• One of interesting is that all beacons include the position and velocity of satellite using own developed GPS receivers!

Structure of simple beacon (45 bytes)

Structure of full beacon (162 bytes)

• If you receive any signals from SNUGLITE cubesat, please let us know!
• All the data which you send us will be helpful to our research. (Earth quake detection, Space environment observation, Satellite monitoring and so on)
• We would appreciate it if you send us as much data as possible. Also, if any paper utilizes your data, we will provide a certificate that your data has helped with the paper. (e-mail: snuglite@gmail.com)

2018/12/12
Object AC is the closest to SNUGLITE.