Looks like there is about 50 ms between them. see http://rcallen.com/iqimps.png
The sine wave at the end is at 48000/2048 Hz period 42.666 ms Richard Robert McGwier <[EMAIL PROTECTED]> wrote: (11/23/2005 20:29) >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 >>>> >>>> >>>> >>>> >>>> >>>> >>>>------------------------------------------------------------------------ >>>> >>>> >>>> >>>-- >>>Laziness is the number one inspiration for ingenuity. Guilty as charged! >>> >>> >> >> >> >> > > >-- >Laziness is the number one inspiration for ingenuity. Guilty as charged!
