On 04/30/2014 05:17 PM, David Halls wrote:
Sorry, my fault - I altered the FDE so it *does* give soft outputs,
because the constellation decoder makes hard decisions anyway - so I
didn't see the need for it to be done twice.
How exactly have you implemented that?
I forgot i'd made changes :s
On 30.04.2014 11:51, David Halls wrote:
Hi Martin, All,
Has anyone noticed that the final symbol of any burst (no matter how
many packets in a transmission) appears slightly 'noisy' in the OFDM
example code? Is it something to do with my set-up?
I attach a picture of the eq'd FD constellation
Hi Martin,
This is OTA or over a cable, 2.48GHz using the N210 with XCVR2450. The results
I sent are over a cable, and the results I sent are post equalizer.
It is only the final symbol of a burst, not the final symbol of each packet.
I agree they should all be equally noisy, and I am certain
On 30.04.2014 13:14, David Halls wrote:
Hi Martin,
This is OTA or over a cable, 2.48GHz using the N210 with XCVR2450. The
results I sent are over a cable, and the results I sent are post equalizer.
Which equalizer are you using? A custom one? Those in GNU Radio aren't
fantastic, and they
Hi,
It's just the built in basic FDE. Its not awesome, but works well enough at
high SNR.
Yes, when I send multiple packets, its only the last OFDM symbol of the last
packet that is affected.
I have tried suffixing FFT_len/4 (i.e. 16 = CP) lots of 0's in the TD at the
transmitter, and this
Hi Martin,
Setting the rolloff factor in the cyclic prefixer to CP_len (16 samples) fixes
the problem?! Previously I had rolloff = 0.
Any thoughts?
DH
From: Martin Braun [martin.br...@ettus.com]
Sent: 30 April 2014 14:56
To: David Halls;
On 30.04.2014 16:03, David Halls wrote:
It's just the built in basic FDE. Its not awesome, but works well enough
at high SNR.
Hm, the FDE doesn't output soft info, so I'm stumped why you'd see
anything other than clean constellation points in the first place.
Yes, when I send multiple
Sorry, my fault - I altered the FDE so it *does* give soft outputs, because the
constellation decoder makes hard decisions anyway - so I didn't see the need
for it to be done twice.
I forgot i'd made changes :s But now maybe I understand why people haven't seen
this issue - because they have
