Burst start/end phase error

Thomas Tsou tom at tsou.cc
Fri Dec 14 04:52:42 UTC 2012


On Thu, Dec 13, 2012 at 11:16 PM, Alexander Chemeris
<alexander.chemeris at gmail.com> wrote:
>> No, not yet. I tried some other combinations that worked fine on the
>> signal tester, but the handset still wasn't happy. I'm not yet sure
>> why.
>
> Did you check power mask with the signal tester, or phase error too?
> May be differential modulation is somehow broken by this change?

The modified case I measured earlier was improved in power mask and
phase error, but just failed in real testing. There is an overall
phase rotation from the added bits, but this technically shouldn't
matter - and adding only the trailing bits also caused the failure
condition. My guess is that this is ramp/power related and not
directly due to modulation.

My power shaping profile was really a coarse guesstimate, so that may
be a factor. But I'm surprised it doesn't work because having no power
profile seems to work quite well (without the extra bits).

  Thomas




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