KAkawfey·Jun 24, 2019
The FCC license registration [0] contains some interesting information.
- Experimental radio service call sign WM9XPA
- Using an Icom IC-821C Transceiver [1], a twenty-something year old VHF/UHF ham radio...wow for a $7M project couldn't they have spent more on a radio? Well, maybe not, I'll get to that in a minute.
- Ground station is in the middle of nowhere? I think something with the Lat-Lon might be off if they mention West Lafayette, IN as the city (Purdue is located here).
- The satellite's datalink is FSK on 437.025 MHz, designation 15K0F1D, which is a standard 15kHz wide FM modulated FSK signal. The signal's parameters are not known from the registration but I googled some more and found their FAQ which links to their protocol description [2]. In a nutshell it's run-of-the-mill AX.25 at 9600baud using a simple encoding for variou
Read the rest
s parameters. You could decode this easily with an SDR and Direwolf [3] or GNURadio. This is why they can use the low-cost ham radio. I'm also willing to bet they'll be leveraging submissions from amateur radio operators and the automated SATNOGS network [4] to harvest more data.
[0] https://fcc.report/ELS/The-Planetary-Society/1029-EX-ST-2019
[1] http://www.rigpix.com/icom/ic821h.htm
[2] https://planetary.s3.amazonaws.com/projects/lightsail/manual...
[3] https://github.com/wb2osz/direwolf/blob/dev/doc/README.md
[4] https://satnogs.org/