It looks like there's a dev call tomorrow. Is that 1700 or 1800 UTC? 
https://gnuradio.org/redmine/projects/gnuradio/wiki/Call20141120

As for input to the digital mod and packet structure discussion, I have a few 
questions, or at least food-for-thought for tomorrow:

-          It looks like the correlate_and_sync work is promising for allowing 
carrier and timing recovery loops to adjust more quickly when dealing with 
bursty, packetized traffic. However, most of the GR modem applications I've 
seen use the correlate_access_code block without the time and phase estimates 
being done on the preamble. I know the paradigm is slightly different, i.e. 
matched-filter preamble correlator vs. counting access code bit errors after MF 
and slicing, but is the intent to eventually merge the two approaches together?

-          What's the best way to handle the sudden ramp in power at the start 
of a burst? Use squelch to detect power above a threshold? Use AGC? This may be 
a fundamental radio receiver design question but I think it makes sense to ask 
it in the context of how these blocks are implemented. In gr-air-modes it looks 
like the preamble detector scans for a rapid change in sample "voltage" before 
initiating a preamble search. This seems more efficient if packet traffic is 
expected to be low, otherwise all you're doing is correlating against noise 
(correlate_and_sync) or junk bit decisions (correlate_access_code). If I've 
misunderstood anything here, please advise.

Thanks,
Sean
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