KSAT2 Project


This page describes a next project succeeded to the Hayato (KSAT) project.

Missions of KSAT2

 1. Study on Forcast of Localied Downpour and Tornado
   In-orbit experiments of an original observation method of atmospheric water vapor.
 2. Take Earth Live Images from Space
   Ku-band high-speed data transmission, one shot / a few seconds.
 3. Basic Experiments for LEO Positioning Satellites
   Frequency and phase synchronization between a ground-base system and a satellite.
 4. Orbit Determination Experiments with Radio Interferometer
   Essential item for nano-satellite orbiting at very low earth orbit.
 5. Satellite Traking Experiment at Very Low Earth Orbit

   Evaluation of Earth's atmosphere to the satellite.
 6. Verification of Pantograph-type Extending Boom in Space
   The boom was originally designed and is fit for compact satellites.
 7. Messages of Encourgement from Space to Japan
   Hand-lettered messages and heart warm pictures, especially from children eesponsible for the future.

Imaginary Drawing of Satellite in Space     (Expand by Click)

  KSAT2 orbiting at the altitude of ISS (left panel), and before and after deployment from POD (right panel / original design version).
  Illuststration of KSAT2   Fł̎p

Outloook of KSAT2    (Expand by Click)

  Outlook of KSAT2 before (left panel) and after (right panel) deployment from POD (revised verion).
 Illuststration of KSAT2   
  Main body of the satellite has a shape of 10 cm Cube, and its mass will be 1.5 kg.
  An expanding boom for attitude control and two solar paddles are attached to the main body.

System Block Diagram   (Expand by Click)


  Block diagram
  To be low power dissipation and compact comparing with KSAT.
  Redandancy with dual communication lines.
  Improvement of Power Efficiency with MPPT control.

Communication

    Dual uplink lines, Dual downlink lines and a beacon signal line.

- Frequency and Transmissio Rate -

Frequency Band Moduration Method Transmission Rate Purpose
Uplink UHF Band F2D 1 kbps  Commands
S Band G2D 1 kbps  Command (Backup)
Downlink S Band G1D 200 ksps  HK Data
Ku Band G1D 1 Mbps or Carrier  Image and Beacon

  # Coding by viterbi algorithm is applied to S-band downlin data.

Schedule    (Expand by Click)


  Milestone

Situation after Launch

 Feb.28,2014,  3:37
      Launch from Tanegashima. Separation of Hayato II in the South Pacific.
 Feb.28,2014, 18:35-18:48
      Receive Ku-band beacon from Hayato II at Kagoshima University station.
      Send command in the UHF band towards Hayato II from Tohoku University station.
      → Receive S-band telemetry at Tohoku University, Chiba Institute of Technology and other station.
 Mar.1,2014,  17:41-17:51
      Send command from Tohoku University station.
      → Receive S-band telemetry at Tohoku University, Chiba Institute of Technology and other station.
 Mar.2,2014,  3:20- 3:31
      Receive Ku-band beacon at Kagoshima University station.
      Send command from Tohoku University station.
      → Receive S-band telemetry at Tohoku University, Chiba Institute of Technology and other station.
 (And later, until early morning March 9)
      Ku-band beacon is continuously received.
      Send a command towards Hayato II, but no response from Hayato II.
 Mar.9,2014,  16:13-16:26
      Send command in the S-band from Kagoshima University station.
      → Receive S-band telemetry at Tohoku University station.
 (After that, Hayato II response to S-band command from Kagoshima University station)

Operating Conditions
 1. Telemetry data from Hayato II of March 1 and February 28
   · Feb.28  Battery voltage 3.69V, temperature 12.8 °C → Within the normal range
                 Power supply status to each machine is normal
   · Mar. 1  Battery voltage 3.75-4.3V, temperature 10-12 °C → Within the normal range
   · Can not be confirmed paddle deployment, boom extension ← As judged by the power generation situation in solar cells
 2. Telemetry data from Hayato II of March 12
   · Battery voltage 3.07V → Within the normal range
   · Battery temperature 0.39 °C → Slightly lower (0°C nearby)
   · Solar cells (current) +Y_cell : 0.58A +Y_PDL(Reverse surface of the boom) : 0.85A
      →Paddle is more likely to deploy
 3. Radio wave reception status
   · Strength of Ku-band radio beacon is fluctuating time in a few 10 seconds
   · Fluctuates time in seconds both S-band telemetry radio waves, Ku-band telemetry
   · Strength of Ku-band telemetry radio waves is lower than expected

Orbit of Hayato II    (Expand by Click)


  Orbit of Hayato II

Ku-band Radio Beacon    (Expand by Click)


  Ku-band radio beacon   Ku-band radio beacon2

  Doppler shift of Ku-band beacon radio wave is frequency synchronization and Ku-band telemetry signal.
  

Ku-band Radio Telemetry    (Expand by Click)


  Ku-band radio telemetry

Ku-band Dynamic Radio Spectrum    (movie)


  Spectrum Sample

   Apr. 8, 2014  21:46 (76,492KB)

   Apr.10, 2014  21:01 (30,454KB)

   Apr.26, 2014  16:31 (46,119KB)

   Apr.27, 2014  02:01 (47,329KB)

   Apr.27, 2014  16:43 (56,889KB)

   Apr.29, 2014  15:31 (52,392KB)

   May. 3, 2014  14:31 (32,870KB)

   May. 7, 2014  22:45 (33,313KB)

   May.12, 2014  11:34 (29,408KB)

   May.16, 2014  10:50 (31,388KB)



Masanori Nishio    Jun. 5, 2014 Revised