Carrier Sensing only in gr_packet_sink?

GNU Radio
1

Hi!

I have a short question: in my implementation of a state machine to
implement a parser for a MAC sublayer standard (802.15.4) I used a
Sync-Block. Now I found out that carrier_sense() is only in
gr_packet_sink class. Does this make sense at all? Normally I’d apply
some Carrier Sensing right before modulation, mostly to avoid blocks
wasting performance on iterating over noise. I’m aware that a Squelch
Filter might archive a similar effect, but that still means the other
Signal Block go into general_work() routines.
So, why is carrier_sense() not in gr_sync_block etc.?

Best,
Marius

2

On Fri, May 25, 2012 at 4:32 AM, Marius [email protected] wrote:

So, why is carrier_sense() not in gr_sync_block etc.?

Best,
Marius

That packet sink block is very old and mostly just an example, now.
It’s largely been replaced by frame_sink_1 and
digital_correlate_access_code_bb (note that we will be moving
frame_sink_1 into gr-digital in 3.7; there was some talk about
removing packet_sink altogether).

If you follow the benchmark examples in
gr-digital/examples/narrowband, we actually implement the carrier
sensing in there, prior to the modulation as you say.

Hope this helps.

Tom