Discussion in 'Satellite and Space Communications' started by KC9SGV, Mar 31, 2019.
I hadn't investigated but I had the same thought..
The payload is on the PSLV 4th stage and gets its power from solar panels and batteries attached to the 4th stage. The 4th stage is expected to remain in orbit for about 6 months.
Once again, Paul sets me straight. Ok, we have a little bit longer than "early days", so that's good. I also noticed that my SatNogs station picked up what appeared to be a much stronger packet over the last 24 hours - maybe that's good news. I've got a 58° pass later this morning, maybe I can find time to run out and give it another try.
More hits on Twitter.
don't do twitter. Does the "ARISS" path work?
Also, no mention of antenna's/pre-amps or Tx power used that I can find.
Whelp.... Another pass with no decodes. I did hear a flurry of packets at one point, which suggests there may have been digipeats, but who knows. I'll try and decode the audio that my satnogs station caught later tonight.
K4KDR has reported that on a pass today of 69°, he was only able to get one packet into the digipeater (right at TCA), and that's at 50W with an az/el system using wimo x-quads. I suspect this digi isn't going to be terribly friendly to HT users.
If they use one antenna for both AIS and APRS...
(APRS was added as an afterthought, completed in six days, just a box, no antenna, no battery, no power panels.)
If this is the case, AIS has thousands of ships all trying to work the antenna automatically.
There are only a few hams trying to work APRS through the same antenna per pass.
Without proper diplexing, how would this system not be blind to APRS ?
AIS is ~160 MHz for ship to shore connections.
Not sure what the sat connection freq would be for AIS.
Maybe it is time for AMSAT India and Exseedspace to inform us hams here ?
So, in researching AIS, the time slot phenomenon is telling..
AIS knows when to transmit, in order not to get bumping transmissions.
On an antenna where both AIS and APRS operates...(IF this the case, and we do not at the moment have further information about the fourth stage setup), AIS transmissions to and from the ships are time slotted. But what about the random APRS transmissions ?
Maybe APRS telemetry and position beaconing from the sat could be time slotted in with the AIS transmissions from the sat.
But what about APRS message uploads from hams ?
Am I overthinking this, or are there indeed separate antennas for AIS and APRS on this rocket fourth stage ?