I figured out the problem. There were two things I wasn't taking into
account:
- The modulator reads bits in MSB order, which means that I should pack
them the same way.
- There is a bit framing problem (can be solved using packet
encoder/decoder). Checked converting both sequences to
It's not just an offset problem. Even though in the output file, there is a
delayed sequence, it doesn't have the right bits. As it has exactly the
same period it leads me to believe that it's just a problem of phase sync.
Attached is a minimal grc file.
Cheers,
Fabián
On Wed, Oct 3, 2012 at 12:
On Mon, Oct 1, 2012 at 1:27 PM, Fabián Kozynski wrote:
> As sanity check I'm trying a simple flowgraph in GRC with a QAM mod/demod:
>
> Vector Source ==> Throttle ==> QAM Mod ==> QAM Demod ==> Unpacked to Packed
> ==> File Sink
>
> The parameters in the mod/demod are as default. I also have a File
As sanity check I'm trying a simple flowgraph in GRC with a QAM mod/demod:
Vector Source ==> Throttle ==> QAM Mod ==> QAM Demod ==> Unpacked to Packed
==> File Sink
The parameters in the mod/demod are as default. I also have a File Sink
before the mod.
In the output I see first a bunch of zeros,
