Re: [Discuss-gnuradio] loss of packets during reception

[Eric Blossom]

On Fri, Aug 21, 2009 at 06:47:12AM -0700, anma wrote:
> 
> hi,
>    i am working on a project in which 2 connect statements are defined in
> the same top_block. both connections begin with usrp source. i would like to
> know what exactly is the sequence of execution of the flowgraph when
> tb.start is called.
> do the 2 flowgraphs execute in parallel or 1 after the other?(no
> hierarchical blocks are used)

Depending on the number of cores in your machine, they will either run
in parallel or not.  Generally this doesn't matter for correctness,
since the data flow abstraction doesn't make any promises in this
area.

>     also,in this program ,both receiver and transmitter are tuned to the
> same frequency but the receiver is not receiving all the packets?does anyone
> know why this is happening?

You've haven't given us the first clue as to what you're doing.
Are the transmitter and receiver running at the same time?  If so,
there's a good chance that the transmitter is saturating the receiver
front end.

Have you tried logging the received baseband data, and looking at it
in octave, scipy, etc?  Does it look like what you expect?

Please see:

  http://gnuradio.org/trac/wiki/ReportingErrors
  http://www.catb.org/~esr/faqs/smart-questions.html

for suggestions on how to ask questions in a way that will improve the
likelihood of getting useful assistance from the people that read this
list.

Eric