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STP questions


A some questions and clarifications regarding your proposed STP.

RUDAK TLM is AX.25 UI frames.  There is no error check information within 
the data portion of the frame.  A TNC strips off the AX.25 CRC and 
typically provides a KISS wrapped frame to the computer.  Would the 
spacecraft telemetry block include the KISS wrapper?  I assume yes.

Some satellites may send TLM frames as often as every 2 or 3 seconds.  Is 
each frame a separate messages in STP, proceeded by the full set header 
lines?  I assume yes.

Many existing 400 bps PSK demods send only 512 bytes of the AO-40 TLM to 
the computer so no CRC or other error checking is available.  Would the 
sync vector still be included in the spacecraft telemetry block?  I assume yes.

One might tentatively suggest the following Source definitions for RUDAK in 

However, it is possible for either rudak processor (a or b) to send 
independent data streams on as many as 7 different downlink frequencies, or 
even alternately on the same frequency.  For example when a 153k6 downlink 
is activated the data stream may contain the full TLM data set while the 
9k6 downlink would be constrained to a small subset.  Should that be 
implemented how would we define the Source?  Should there be a another 
layer under the subsystem name?  The frequency may not always identify the 
sub-subsystem either because they send on the same frequency or because of 
Doppler (recognizing the frequency header should be the nominal 
frequency).  It would be possible to identify the sub-subsystem by 
examining the callsigns but that would require decoding the spacecraft 
telemetry block which seems to corrupt the concept of the header.  Thoughts?


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