LEO Class 1

[This page is currently out of date – we currently use modified USB TV tuners as software defined radio receivers for maximum flexibility at low cost coupled to a very low cost microcontroller board. Updated information will be provided shortly. If anything is unclear or you have any suggestions for additional content, please leave a comment at the bottom of this page or email support@myGroundStations.com – thanks!]

LEO Class 1 antenna

myGroundStations.com LEO Class 1 ground station – a roof top low-speed downlink only ground station.

These ground stations support 70cm receive only communication with spacecraft with the possibility of expansion of coverage to 2m and S-band one way communication in the future.

LEO Class 1 block diagram

Antennas:

• Omnidirectional
• 70cm Lindenblad
• Future support for additional omnidirectional 2m Lindenblad and a small inexpensive steerable S-band antenna planned
• Optional heated radome housing for use in extreme climates

Data throughput:

• up to 1200bps
• typical 432KB per satellite per day decoded data
• maximum 10.4MB per day decoded data

Expected cost:

• Less than GBP 130 / EUR 160 / USD 200

Radios:

• 1 x myGroundStations.com soft radio or
• 1 x Yaesu FT-817ND (additional cost)

Software:

• myGroundStations.com scheduler
• myGroundStations.com baseband store and forward client
• myGroundStations.com soft terminal node controller client
• cloud GENSO GSS client

Locations:

• Sufficient to provide up to 24 hours a day contact with a 700km low earth orbit spacecraft
• Thirty or more globally distributed to provide at least eighteen hours a day contact
• Several hundred to provide a RAIGS (redundant array of inexpensive ground stations) research system
• The map below shows the LEO Class 1 ground station locations

This map is displayed using Google Maps or can be used to launch Google Earth. To view all the ground stations in Google Earth (which you can download for free from earth.google.com), click on ‘View larger map’ and then on ‘View in Google Earth’ at the top right of the window. Google Maps sometimes has problems with circles near the poles, so please ignore any horizontal lines you might see.

Active ground stations are marked with a pin and the approximate area of coverage they provide for a 700km LEO myPocketQub is marked in green. Locations that have offered to host a ground station but have not installed hardware yet are marked in yellow. Locations where we would like to have at least one ground station installed to ensure minimal coverage are marked in red. Please note that some locations have had a random error of up to +/- 50km applied to them to protect their privacy.

We wish to over build the network so we can do lots of interesting research so if you could host a ground station anywhere on earth, please visit our new sites page – thanks!

You can download the KML file for viewing in Google Earth by clicking here.

Background

This ground station is designed to be installed by someone with minimal technical knowledge. It is designed to receive data at a maximum of 1200bps but be cheap enough to ensure global deployment for continuous communications with a LEO satellite as part of a RAIGS. It is small enough to be installed on a standard TV or FM aerial.

It is available in a number of configurations which allow a user to trade-off ease of installation against cost.

The cheapest configuration costs approximately GBP 65 but requires a PC to control it and provide internet connectivity plus cables from the PC to the masthead.

The easiest configuration costs approximately GBP 200 and includes an Arduino based masthead controller with WiFi and solar panel so no wires need to be run to the mast-head. It is self configuring, so as long as the system can connect to the WiFi network, the system can set itself up with no further configuration.

These prices are expected to drop at least 50% if sufficient demand to warrant bulk buying emerges.

Antenna hardware:

• 70cm Lindenblad based on this design by AA2TX – GBP 35. We plan to supply the antenna part or fully assembled based on the G7HIA kit, the assembly instructions for which can be seen here.

Radio hardware:

• 70 cm preamplifier (based on this design by G0MRF – GBP 20
• Modified Space Radio based on this design by AA2TX – GBP 10

Control hardware can be either:

• Standard PC with RS232 port, line in socket, headphone socket and USB capable of running VMWare Player to run a 512MB RAM, 4GB hard drive myGroundStations.com virtual machine image (average cost GBP 100)

or

• Arduino Pro Mini (GBP 15) with 2GB SD card (GBP 5) with myGroundStations control scheduler with waveform store and forward software plus one of
  • BlueTooth shield (such as this system – GBP 15) – requires PC for internet connectivity or
  • Ethernet shield (such as this system – GBP 25) – requires wired Ethernet connection for internet connectivity or
  • GPRS shield (such as this system – GBP 69) – requires active cellular telephone network
  • WiFi shield (such as this system – GBP 60) – requires wireless router for internet connectivity
• 12V power supply comprising one of
  • a mains DC power adapter suitable for providing power outdoors or
  • 12V solar panel system with optional battery (such as this system – GBP 60). The battery is only required if you wish to work with satellites not in a sun synchronous orbit.
• A waterproof case to contain the electronics at the mast-head (GBP 5).

The final development and packaging of the hardware and software is underway and is expected to completed in Q4 2010.

Contribute

Do you have a story, information, brochure, manual, link or other relevant content that should be on this page? If so, we would be very grateful if you would leave it as a comment or email support@myGroundStations.com so we can post it here – thanks!