6 Dec
2012
6 Dec
'12
4:13 a.m.
Hi Alexander,
Please try the last commit at
git://github.com/ttsou/openbts-p2.8.git laurent
I tested with 4 samples per symbol as we did in the past. Reducing the
start/end phase error involved adding bits so that there is no partial
phase transition to/from nothing. We then zero out the excess bits
with a simple power mask.
Thomas
6 Dec
6 Dec
4:55 a.m.
Thanks Thomas, I'll try this.
Did you test receive side with this patch?
On Thu, Dec 6, 2012 at 7:13 AM, Thomas Tsou <tom(a)tsou.cc> wrote:
Hi Alexander,
Please try the last commit at
git://github.com/ttsou/openbts-p2.8.git laurent
I tested with 4 samples per symbol as we did in the past. Reducing the
start/end phase error involved adding bits so that there is no partial
phase transition to/from nothing. We then zero out the excess bits
with a simple power mask.
Thomas
--
Regards,
Alexander Chemeris.
CEO, Fairwaves LLC / ООО УмРадио
http://fairwaves.ru
6:48 a.m.
On Thu, Dec 6, 2012 at 8:55 AM, Thomas Tsou <thomastsou(a)gmail.com> wrote:
On Wed, Dec 5, 2012 at 10:55 PM, Alexander Chemeris
<alexander.chemeris(a)gmail.com> wrote:
Got it.
Waiting for the receive side test.
--
Regards,
Alexander Chemeris.
CEO, Fairwaves LLC / ООО УмРадио
http://fairwaves.ru
Thanks Thomas, I'll try this.
Did you test receive side with this patch?
No, the E4406 was plugged in the entire time.
7 Dec
7 Dec
9:28 a.m.
On Wed, Dec 5, 2012 at 10:13 PM, Thomas Tsou <tom(a)tsou.cc> wrote:
Please try the last commit at
git://github.com/ttsou/openbts-p2.8.git laurent
I tested with 4 samples per symbol as we did in the past. Reducing the
start/end phase error involved adding bits so that there is no partial
phase transition to/from nothing. We then zero out the excess bits
with a simple power mask.
It turns out that the transmit tester likes this signal, but my
handsets do not; they do not even recognize it. Perhaps this form of
testing is not as reliable as I thought.
So I reverted the commit to handle start/end phase errors. I also
setup the correlators with single pulse (I see no benefit for the more
complicated modulator on receive), and set timing for 4sps. I receive
RA and normal bursts fine. The start/end transients will need to be
handled a different way.
Thomas
13 Dec
13 Dec
3:04 p.m.
On Fri, Dec 7, 2012 at 12:28 PM, Thomas Tsou <tom(a)tsou.cc> wrote:
On Wed, Dec 5, 2012 at 10:13 PM, Thomas Tsou
<tom(a)tsou.cc> wrote:
Ok, we've tested 'laurent' branch and it works great for both Rx and Tx,
thanks!
Have you had any success with fixing ramp up / ramp down issue?
--
Regards,
Alexander Chemeris.
CEO, Fairwaves LLC / ООО УмРадио
http://fairwaves.ru
Please try the last commit at
git://github.com/ttsou/openbts-p2.8.git laurent
I tested with 4 samples per symbol as we did in the past. Reducing the
start/end phase error involved adding bits so that there is no partial
phase transition to/from nothing. We then zero out the excess bits
with a simple power mask.
It turns out that the transmit tester likes this signal, but my
handsets do not; they do not even recognize it. Perhaps this form of
testing is not as reliable as I thought.
So I reverted the commit to handle start/end phase errors. I also
setup the correlators with single pulse (I see no benefit for the more
complicated modulator on receive), and set timing for 4sps. I receive
RA and normal bursts fine. The start/end transients will need to be
handled a different way.
14 Dec
14 Dec
4:10 a.m.
On Thu, Dec 13, 2012 at 9:04 AM, Alexander Chemeris
<alexander.chemeris(a)gmail.com> wrote:
Ok, we've tested 'laurent' branch and it
works great for both Rx and Tx, thanks!
Have you had any success with fixing ramp up / ramp down issue?
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.
Thomas
5:16 a.m.
On Fri, Dec 14, 2012 at 7:10 AM, Thomas Tsou <tom(a)tsou.cc> wrote:
On Thu, Dec 13, 2012 at 9:04 AM, Alexander Chemeris
<alexander.chemeris(a)gmail.com> wrote:
Did you check power mask with the signal tester, or phase error too?
May be differential modulation is somehow broken by this change?
--
Regards,
Alexander Chemeris.
CEO, Fairwaves LLC / ООО УмРадио
http://fairwaves.ru
Ok, we've tested 'laurent' branch and
it works great for both Rx and Tx, thanks!
Have you had any success with fixing ramp up / ramp down issue?
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.
5:52 a.m.
On Thu, Dec 13, 2012 at 11:16 PM, Alexander Chemeris
<alexander.chemeris(a)gmail.com> wrote:
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
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?
4161
days inactive
4169
days old
8 comments
3 participants
participants (3)
-
Alexander Chemeris -
Thomas Tsou -
Thomas Tsou