There should have been 2048 samples between. If there is not, I made a
mistake and will do the file again. We definitely need the equalizer.
Bob
richard allen wrote:
In our military system tests we acquire 10-20 impulses and sum them
in the frequency domain. If the ripple is actually in the system
then it will stay in. This was what the generals all wanted. In our
seismic stuff, where the geophysicists seem to think it is needed to
find oil, we require the < 1 dB flatness in the frequency domain
plateau of a single impulse.
Another possible problem is that the data before and after the
impulse must be un-modified by another impulse coming along for at
least the time to get thru the last fir filter stage in the sigma-
delta converters. This takes 29 samples in our seismic converters.
At that point the response should have dropped to zero, of course,
but any analog stuff may still be banging about. I usually play it
safe and isolate a single impulse in 1024 samples. I did not
measured the time between the individual pulses in your data.
Impulse respone image is at http://rcallen.com/iqimp.png in case
anyone else wants to see it.
Richard W5SXD
Robert McGwier <[EMAIL PROTECTED]> wrote:
(11/23/2005 18:21)
There is enough there to tell me that we should have done the block
equalizer a long time ago. I did not know about the ripple and the
delay elements they imply.
Bob
richard allen wrote:
One more time.
-----Original Message-----
From: richard allen [mailto:[EMAIL PROTECTED]
Sent: Wednesday, November 23, 2005 7:36 AM
To: 'Robert McGwier'
Cc: [EMAIL PROTECTED]
Subject: RE: [Flexradio] Impulse Wave file
Looks pretty flat. Seismic stuff is spec'ed at 1 db flatness. Analysis
of a single of your impulses. I guess you'll need to sum a bunch.
Richard
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Robert McGwier
Sent: Tuesday, November 22, 2005 9:23 PM
To: [EMAIL PROTECTED] Biz
Subject: [Flexradio] Impulse Wave file
We have an impulse generator on the RFE. And we have (currently hidden)
code to generate a train of pulses. I generated several ten long pulse
trains with the RFE impulse generator and made a wave file.
The large pop at the end of the file is me disengaging the impulse
relay.
ftp.flex-radio-friend.net
u: Friends
p: Flex4U
cd upload/N4HY
get IQ_impulses.wav
Bob
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--
Laziness is the number one inspiration for ingenuity. Guilty as charged!
--
Laziness is the number one inspiration for ingenuity. Guilty as charged!
