On 05/05/2019 01:12 PM, Brian Padalino wrote:
Since it's AM, try shifting your center frequency by a little bit.
Extract the envelope the same way, though.
My thought is the DC cancellation circuitry in the 9361 is killing
your AM waveform, so use a low-IF approach instead.
Brian
You beat me to it. Yes, this will be true of most direct-conversion
architectures--there will be DC-offset removal in the analog
(or digital) pathways before samples are delivered to the host. That
removal process will turn the DC anomaly from a large
spur to a notch, so if you are doing narrow-band AM demodulation at
"DC" in the complex signal domain, some of that signal
will have been removed. Offset tuning eliminates this issue.
On Sun, May 5, 2019 at 1:05 PM franz kurniawan via USRP-users
<usrp-users@lists.ettus.com <mailto:usrp-users@lists.ettus.com>> wrote:
I reduced to -40db, -50db and have the same result..
I attached the pictures of b200mini vs other SDR with the same
signal generator..
I expect the same result with the 'other SDR' result..
The IQ data of b200 is seems to be incorrect (imbalance? )
I have tried the uhd of these version :
v3.14.0.0-rc3 ,
release_003_007_001,
release_003_010_001_000
But all have the same result..
I tried to disable the set_auto_iq_balance to both false and true,
but have no effect..
Thank you
On May 5, 2019 11:27 PM, "Marcus D Leech" <patchvonbr...@gmail.com
<mailto:patchvonbr...@gmail.com>> wrote:
-20dBM is loud. Try backing the generator down to -40dBm
Sent from my iPhone
On May 5, 2019, at 12:14 PM, franz kurniawan
<digitalturtle2...@gmail.com
<mailto:digitalturtle2...@gmail.com>> wrote:
I set the generator at -20db and b200 gain at 50..
I check that there is no cutoff at the usrp output and the
input to AM demod block..
Below are the setting of uhd block in gnuradio
Samp rate 500k
Output type float32
Sync PC clock
Clock rate 10 Mhz external
Freq 121MHz
Gain 50
Ch0 Bandwidth 200000
Thank you
On May 5, 2019 11:05 PM, "Marcus D Leech"
<patchvonbr...@gmail.com <mailto:patchvonbr...@gmail.com>> wrote:
What output level for the generator? What gain setting on
the b205?
Sent from my iPhone
On May 5, 2019, at 11:58 AM, franz kurniawan
<digitalturtle2...@gmail.com
<mailto:digitalturtle2...@gmail.com>> wrote:
So, i try to make AM receiver..
And the resulted demodulated audio was distorted from
its original signal..
So, at this experiment i used signal generator to make
AM with sine wave modulated signal..
I expect to get pure sine wave signal after AM demod
process..
However, the sine wave is distorted as attached picture
I compared with another brand SDR and can get my
expected signal..
So i guess there is some problem with the b210mini
Thank you
On May 5, 2019 10:28 PM, "Marcus D. Leech via
USRP-users" <usrp-users@lists.ettus.com
<mailto:usrp-users@lists.ettus.com>> wrote:
On 05/05/2019 10:53 AM, franz kurniawan via
USRP-users wrote:
Dear USRP users,
I used b210mini and encounter I/Q imbalance as
below picture..
As a result, the analog signal demodulation was
distorted and result a crappy sound..
I
Is there any workaround regarding this issue?
Thank you
Not sure what you mean. The I/Q seem to be about
90deg out of phase wrt one another, which is exactly
what you'd expect.
Could you describe what it is you're trying to do?
Something with an audio demodulator?
_______________________________________________
USRP-users mailing list
USRP-users@lists.ettus.com
<mailto:USRP-users@lists.ettus.com>
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
<IMG-20190505-WA0001.jpg>
_______________________________________________
USRP-users mailing list
USRP-users@lists.ettus.com <mailto:USRP-users@lists.ettus.com>
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
_______________________________________________
USRP-users mailing list
USRP-users@lists.ettus.com
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
