Re: [Discuss-gnuradio] Question on threshold mathematics in correlate_and_sync block

2015-01-02 Thread Andy Walls
On Wed, 2014-12-31 at 15:48 -0500, Andy Walls wrote: On Wed, 2014-12-31 at 14:00 -0500, Andy Walls wrote: Hi. Can someone give me a brief clue about the threshold testing in the correlate_and_sync block? I found my answer in this post:

Re: [Discuss-gnuradio] Question on threshold mathematics in correlate_and_sync block

2015-01-02 Thread Tom Rondeau
On Fri, Jan 2, 2015 at 8:57 AM, Andy Walls a...@silverblocksystems.net wrote: On Wed, 2014-12-31 at 15:48 -0500, Andy Walls wrote: On Wed, 2014-12-31 at 14:00 -0500, Andy Walls wrote: Hi. Can someone give me a brief clue about the threshold testing in the correlate_and_sync block?

Re: [Discuss-gnuradio] Question on threshold mathematics in correlate_and_sync block

2015-01-02 Thread Nick Foster
Hi Tom, Andy, Thanks for the reports and details. I can definitely see the problem with the situation you're describing. We obviously weren't considering that case when we designed the block. We were really expecting any preamble/access code that we were using would have good

Re: [Discuss-gnuradio] Question on threshold mathematics in correlate_and_sync block

2015-01-02 Thread Andy Walls
On Fri, 2015-01-02 at 09:56 -0800, Nick Foster wrote: There is another problem which prevents proper correlation: the end of work coming mid-burst. See the attached End of work mid-corr.png which shows an end of work tag with the value of

[Discuss-gnuradio] Question on threshold mathematics in correlate_and_sync block

2014-12-31 Thread Andy Walls
Hi. Can someone give me a brief clue about the threshold testing in the correlate_and_sync block? In the constructor: for(size_t i=0; i d_symbols.size(); i++) corr += abs(d_symbols[i]*conj(d_symbols[i])); d_thresh = 0.9*corr*corr; corr looks like the value (at offset 0) of

Re: [Discuss-gnuradio] Question on threshold mathematics in correlate_and_sync block

2014-12-31 Thread Andy Walls
On Wed, 2014-12-31 at 14:00 -0500, Andy Walls wrote: Hi. Can someone give me a brief clue about the threshold testing in the correlate_and_sync block? In the constructor: for(size_t i=0; i d_symbols.size(); i++) corr += abs(d_symbols[i]*conj(d_symbols[i]));