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A Few FFTs Short of MPC
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Bret Cahill
Apr 15, 2012, 11:20:20 AM4/15/12
to
What has been and is being called "matched filtering" might better be
called "a few steps short of complete match filtering" [which has the
often desirable effect of _adding_ in some low pass filtering].
Noise is often at higher frequencies so no one is going to complain
too much about this fortuitous get-more-by-doing-less situation.
North didn't have time to be mathematically politically correct during
a war, certainly not before machines costing less than a few days pay
could calculate a dozen 1024 FFTs in seconds.
Mathematicians, however, aren't satisfied with "well it woOOorks"
jerry rigs. Since there isn't any major war going on recovering the
original signal can now be considered, if only as a matter of form.
This is easy to do in the frequency domain. Just take the square root
of the product of signal X template. Excel makes this operation on
complex numbers easy with IMSQRT.
Now you can see the results of the frequency & phase angle matching
without the seemingly inherent low pass filtering effects obscuring
the match.
Engineers like to get lucky with Fortuna but they also like dedicated
operations. Do the _complete_ matched filter. After the original
signal is recovered _then_ you add in whatever additional filtering
you think is necessary.
Even for signal detection recovering the original signal will often be
a better route. What would be easier to detect? A triangle or a
square wave?
Bret Cahill
"The mind invents things more easily than words. That's why so many
bad terms come into existence."
-- Tocqueville
called "a few steps short of complete match filtering" [which has the
often desirable effect of _adding_ in some low pass filtering].
Noise is often at higher frequencies so no one is going to complain
too much about this fortuitous get-more-by-doing-less situation.
North didn't have time to be mathematically politically correct during
a war, certainly not before machines costing less than a few days pay
could calculate a dozen 1024 FFTs in seconds.
Mathematicians, however, aren't satisfied with "well it woOOorks"
jerry rigs. Since there isn't any major war going on recovering the
original signal can now be considered, if only as a matter of form.
This is easy to do in the frequency domain. Just take the square root
of the product of signal X template. Excel makes this operation on
complex numbers easy with IMSQRT.
Now you can see the results of the frequency & phase angle matching
without the seemingly inherent low pass filtering effects obscuring
the match.
Engineers like to get lucky with Fortuna but they also like dedicated
operations. Do the _complete_ matched filter. After the original
signal is recovered _then_ you add in whatever additional filtering
you think is necessary.
Even for signal detection recovering the original signal will often be
a better route. What would be easier to detect? A triangle or a
square wave?
Bret Cahill
"The mind invents things more easily than words. That's why so many
bad terms come into existence."
-- Tocqueville
brent
Apr 15, 2012, 12:24:21 PM4/15/12
to
Bret Cahill
Apr 15, 2012, 12:39:02 PM4/15/12
to
brent
Apr 15, 2012, 12:40:11 PM4/15/12
to
Bret Cahill
Apr 15, 2012, 5:12:41 PM4/15/12
to
What has been and is being called "matched filtering" might better be
called "a few steps short of complete match filtering" [which has the
often desirable effect of _adding_ in some low pass filtering].
Noise is often at higher frequencies so no one is going to complain
too much about this fortuitous get-more-by-doing-less situation.
Moreover North didn't have time to be mathematically politically
called "a few steps short of complete match filtering" [which has the
often desirable effect of _adding_ in some low pass filtering].
Noise is often at higher frequencies so no one is going to complain
too much about this fortuitous get-more-by-doing-less situation.
correct during a war, certainly not before machines costing less than
a few days pay could calculate a dozen 1024 FFTs in seconds.
Mathematicians, however, aren't satisfied with "well it woOOorks"
jerry rigs. Since there isn't any major war going on recovering the
original signal can now be considered, if only as a matter of form.
This is easy to do in the frequency domain. Just take the square root
of the product of signal X template. Excel makes this operation on
complex numbers easy with IMSQRT.
Now you can see the results of the frequency & phase angle matching
without the seemingly inherent low pass filtering effects obscuring
the match.
Engineers like to get lucky with Fortuna but they also like dedicated
operations. Do the _complete_ matched filter. After the original
signal is recovered _then_ you add in whatever additional filtering
you think is necessary.
Even for signal detection recovering the original signal will often be
a better route. What would be easier to detect? A triangle or a
square wave?
Bret Cahill
"The mind invents things more easily than words. That's how so many
a few days pay could calculate a dozen 1024 FFTs in seconds.
Mathematicians, however, aren't satisfied with "well it woOOorks"
jerry rigs. Since there isn't any major war going on recovering the
original signal can now be considered, if only as a matter of form.
This is easy to do in the frequency domain. Just take the square root
of the product of signal X template. Excel makes this operation on
complex numbers easy with IMSQRT.
Now you can see the results of the frequency & phase angle matching
without the seemingly inherent low pass filtering effects obscuring
the match.
Engineers like to get lucky with Fortuna but they also like dedicated
operations. Do the _complete_ matched filter. After the original
signal is recovered _then_ you add in whatever additional filtering
you think is necessary.
Even for signal detection recovering the original signal will often be
a better route. What would be easier to detect? A triangle or a
square wave?
Bret Cahill
brent
Apr 15, 2012, 5:21:33 PM4/15/12
to
Jerry Avins
Apr 15, 2012, 11:25:37 PM4/15/12
to
On 4/15/2012 11:20 AM, Bret Cahill wrote:
...
> Mathematicians, however, aren't satisfied with "well it woOOorks"
> jerry rigs.
I resent that. The word is "jury rig".
...
Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
...
> Mathematicians, however, aren't satisfied with "well it woOOorks"
> jerry rigs.
...
Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Eric Jacobsen
Apr 15, 2012, 11:28:13 PM4/15/12
to
On Sun, 15 Apr 2012 23:25:37 -0400, Jerry Avins <j...@ieee.org> wrote:
>On 4/15/2012 11:20 AM, Bret Cahill wrote:
>
> ...
>
>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>> jerry rigs.
>
>I resent that. The word is "jury rig".
> ...
>
>Jerry
Dangit. After the story about doing the field weld with an in-place
>On 4/15/2012 11:20 AM, Bret Cahill wrote:
>
> ...
>
>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>> jerry rigs.
>
>I resent that. The word is "jury rig".
> ...
>
>Jerry
car battery and multiple pairs of sunglasses I was pretty certain it
was named after you. ;)
Eric Jacobsen
Anchor Hill Communications
www.anchorhill.com
robert bristow-johnson
Apr 15, 2012, 11:55:01 PM4/15/12
to
On 4/15/12 11:28 PM, Eric Jacobsen wrote:
> On Sun, 15 Apr 2012 23:25:37 -0400, Jerry Avins<j...@ieee.org> wrote:
>
>> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>>
>> ...
>>
>>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>>> jerry rigs.
>>
>> I resent that. The word is "jury rig".
who knows what this person meant? the word could be anything.
> On Sun, 15 Apr 2012 23:25:37 -0400, Jerry Avins<j...@ieee.org> wrote:
>
>> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>>
>> ...
>>
>>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>>> jerry rigs.
>>
>> I resent that. The word is "jury rig".
now someone named Jury Avins is gonna resent it.
there's always someone who'll resent some term.
at the expense of offending threaded parts, i now say "we got screwed".
when i was a kid, the word was "gypped" or even "jewed". i can't
imagine anyone would take offense at that.
>> ...
>>
>> Jerry
>
> Dangit. After the story about doing the field weld with an in-place
> car battery and multiple pairs of sunglasses I was pretty certain it
> was named after you. ;)
battery. i'd like to hear that.
i can only tell the story of a -35 F January day in Grand Forks North
Dakota in the 70s (during a 2 week period that never got in the +
territory) and (since lead-acid batteries do better if they get a little
warmer than -35F) a method i used to use the batteries own stored energy
to warm it up so this dumb car would start. i guess i just told it.
--
r b-j r...@audioimagination.com
"Imagination is more important than knowledge."
Bret Cahill
Apr 16, 2012, 12:15:47 AM4/16/12
to
> > Mathematicians, however, aren't satisfied with "well it woOOorks"
> > jerry rigs.
>
> I resent that. The word is "jury rig".
>
> ...
>
> Jerry
http://jerryrig.com/
> > jerry rigs.
>
> I resent that. The word is "jury rig".
>
> ...
>
> Jerry
brent
Apr 16, 2012, 12:45:08 AM4/16/12
to
Bret Cahill
Apr 16, 2012, 1:01:14 AM4/16/12
to
Androcles
Apr 16, 2012, 5:08:35 AM4/16/12
to
"Jerry Avins" <j...@ieee.org> wrote in message
news:IiMir.1281$M37...@newsfe01.iad...
> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>
> ...
>
>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>> jerry rigs.
>
> I resent that. The word is "jury rig".
>
> ...
>
> Jerry
As a lurker trying to decide who is correct I see myself as
>
> ...
>
>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>> jerry rigs.
>
> I resent that. The word is "jury rig".
>
> ...
>
> Jerry
a juror. I have not been rigged, it seems more like a jerry
rig to me.
Androcles
Apr 16, 2012, 5:14:48 AM4/16/12
to
"robert bristow-johnson" <r...@audioimagination.com> wrote in message
news:jmg56l$4gh$1...@dont-email.me...
> plausible. but i never heard the story about arc-welding using a car
> battery. i'd like to hear that.
>
i can only tell the story of a -35 F January day in Grand Forks North
> Dakota in the 70s (during a 2 week period that never got in the +
> territory) and (since lead-acid batteries do better if they get a little
> warmer than -35F) a method i used to use the batteries own stored energy
> to warm it up so this dumb car would start. i guess i just told it.
>
> --
>
> r b-j r...@audioimagination.com
>
> "Imagination is more important than knowledge."
Einstein that said it.
brent
Apr 16, 2012, 6:58:47 AM4/16/12
to
Bret Cahill
Apr 16, 2012, 11:16:50 AM4/16/12
to
> > "Imagination is more important than knowledge."
> Only for a moron without any knowledge, like the idiot
> Einstein that said it.
Nietzsche clarifies:
> Only for a moron without any knowledge, like the idiot
> Einstein that said it.
"Compared to a genius, that is, he who begets or gives birth, the
scholar comes off a bit like an old maid. He's not conversant with
the two most valuable functions of man."
Fred Marshall
Apr 16, 2012, 11:32:54 AM4/16/12
to
On 4/15/2012 8:25 PM, Jerry Avins wrote:
> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>
> ...
>
>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>> jerry rigs.
>
> I resent that. The word is "jury rig".
>
> ...
>
> Jerry
Jerry,
> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>
> ...
>
>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>> jerry rigs.
>
> I resent that. The word is "jury rig".
>
> ...
>
> Jerry
You are older than that! You reference the more recent usage. I'd
never even heard "jury rig" in this context before. Not to be confused
with "rigged jury".
Fred
Fred Marshall
Apr 16, 2012, 11:34:26 AM4/16/12
to
On 4/15/2012 8:55 PM, robert bristow-johnson wrote:
Suddenly I'm seeing:
Subject: ...
First they were postings by Bret.
But now by r b-j ??????
Fred
Suddenly I'm seeing:
Subject: ...
First they were postings by Bret.
But now by r b-j ??????
Fred
Fred Marshall
Apr 16, 2012, 11:35:42 AM4/16/12
to
robert bristow-johnson
Apr 16, 2012, 4:29:48 PM4/16/12
to
the thread in Google Groups.
i did adopt it. but i'm sorta hypocritical, since i was advocating
starving the troll.
Fred, there was something else you said in another thread that i was
gonna respond to, but i didn't have time at the moment and now i can't
find it. might you know what it was?
Fred Marshall
Apr 16, 2012, 5:18:01 PM4/16/12
to
On 4/16/2012 1:29 PM, robert bristow-johnson wrote:
> Fred, there was something else you said in another thread that i was
> gonna respond to, but i didn't have time at the moment and now i can't
> find it. might you know what it was?
Wow. What a question!! Implying that I would know what you were
> Fred, there was something else you said in another thread that i was
> gonna respond to, but i didn't have time at the moment and now i can't
> find it. might you know what it was?
thinking at some time in the past.....
THE OBVIOUSLY OMNISCIENT ONE RESPONDS:
jerry-rigged
:-)
Jerry Avins
Apr 17, 2012, 12:55:38 AM4/17/12
to
On 4/15/2012 11:55 PM, robert bristow-johnson wrote:
> On 4/15/12 11:28 PM, Eric Jacobsen wrote:
>> On Sun, 15 Apr 2012 23:25:37 -0400, Jerry Avins<j...@ieee.org> wrote:
>>
>>> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>>>
>>> ...
>>>
>>>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>>>> jerry rigs.
>>>
>>> I resent that. The word is "jury rig".
>
> who knows what this person meant? the word could be anything.
>
> now someone named Jury Avins is gonna resent it.
>
> there's always someone who'll resent some term.
>
> at the expense of offending threaded parts, i now say "we got screwed".
> when i was a kid, the word was "gypped" or even "jewed". i can't imagine
> anyone would take offense at that.
>
>>> ...
>>>
>>> Jerry
>>
>> Dangit. After the story about doing the field weld with an in-place
>> car battery and multiple pairs of sunglasses I was pretty certain it
>> was named after you. ;)
"Jerry built", a disparagement dating from WWI. "Jury rig" A temporary
> On 4/15/12 11:28 PM, Eric Jacobsen wrote:
>> On Sun, 15 Apr 2012 23:25:37 -0400, Jerry Avins<j...@ieee.org> wrote:
>>
>>> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>>>
>>> ...
>>>
>>>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>>>> jerry rigs.
>>>
>>> I resent that. The word is "jury rig".
>
> who knows what this person meant? the word could be anything.
>
> now someone named Jury Avins is gonna resent it.
>
> there's always someone who'll resent some term.
>
> at the expense of offending threaded parts, i now say "we got screwed".
> when i was a kid, the word was "gypped" or even "jewed". i can't imagine
> anyone would take offense at that.
>
>>> ...
>>>
>>> Jerry
>>
>> Dangit. After the story about doing the field weld with an in-place
>> car battery and multiple pairs of sunglasses I was pretty certain it
>> was named after you. ;)
repair, often to a mast, at sea.
> plausible. but i never heard the story about arc-welding using a car
> battery. i'd like to hear that.
hangar wire held in the clamp of a jumper cable wrapped a few times
through the center hole in the spare tire. The inductance gives the arc
a smidgeon of stability.
> i can only tell the story of a -35 F January day in Grand Forks North
> Dakota in the 70s (during a 2 week period that never got in the +
> territory) and (since lead-acid batteries do better if they get a little
> warmer than -35F) a method i used to use the batteries own stored energy
> to warm it up so this dumb car would start. i guess i just told it.
Jerry Avins
Apr 17, 2012, 12:58:40 AM4/17/12
to
Jerry Avins
Apr 17, 2012, 1:01:27 PM4/17/12
to
Aks me no questions and I'll tell you no lies.
That's the nuculus of the problem.
Irregardless?
Bret Cahill
Apr 17, 2012, 2:16:02 PM4/17/12
to
> >>> Mathematicians, however, aren't satisfied with "well it woOOorks"
> >>> jerry rigs.
>
> >> I resent that. The word is "jury rig".
>
> >> ...
>
> >> Jerry
>
> > As a lurker trying to decide who is correct I see myself as
> > a juror. I have not been rigged, it seems more like a jerry
> > rig to me.
>
> It takes a long time for a frequent error to become accepted as correct
"A long habit of not thinking a thing wrong, gives it a superficial
> >>> jerry rigs.
>
> >> I resent that. The word is "jury rig".
>
> >> ...
>
> >> Jerry
>
> > As a lurker trying to decide who is correct I see myself as
> > a juror. I have not been rigged, it seems more like a jerry
> > rig to me.
>
> It takes a long time for a frequent error to become accepted as correct
appearance of being right, and raises at first a formidable outcry in
defense of custom. But the tumult soon subsides. Time makes more
converts than reason."
-- Thomas Paine (1776)
Still, tumults are rare in math and there isn't much of one here
either. Everyone with a Ph.D. in math has already or will soon
readily admit that "matched filtering" isn't the best term.
North would have been better off just calling it a "partial matched
filter" or just the "North filter."
Now we are stuck with calling the deconvolution of a matched filter
output "the pure match filter" or the "complete match filter" or
"matching only" filter.
Bret Cahill
"All is number."
"The name giver . . ."
-- some ancient Greeks
brent
Apr 17, 2012, 2:35:48 PM4/17/12
to
On Apr 17, 2:16 pm, Bret Cahill <Bret_E_Cah...@yahoo.com> wrote:
> > >>> Mathematicians, however, aren't satisfied with "well it woOOorks"
> > >>> jerry rigs.
>
> > >> I resent that. The word is "jury rig".
>
> > >> ...
>
> > >> Jerry
>
> > > As a lurker trying to decide who is correct I see myself as
> > > a juror. I have not been rigged, it seems more like a jerry
> > > rig to me.
>
> > It takes a long time for a frequent error to become accepted as correct
>
> "A long habit of not thinking a thing wrong, gives it a superficial
> appearance of being right, and raises at first a formidable outcry in
> defense of custom. But the tumult soon subsides. Time makes more
> converts than reason."
>
> -- Thomas Paine (1776)
Jury or jerry? I think the jury is out and it is jury according to
> > >>> Mathematicians, however, aren't satisfied with "well it woOOorks"
> > >>> jerry rigs.
>
> > >> I resent that. The word is "jury rig".
>
> > >> ...
>
> > >> Jerry
>
> > > As a lurker trying to decide who is correct I see myself as
> > > a juror. I have not been rigged, it seems more like a jerry
> > > rig to me.
>
> > It takes a long time for a frequent error to become accepted as correct
>
> "A long habit of not thinking a thing wrong, gives it a superficial
> appearance of being right, and raises at first a formidable outcry in
> defense of custom. But the tumult soon subsides. Time makes more
> converts than reason."
>
> -- Thomas Paine (1776)
jerry. Unfortunately he is stuck with jerry-built...haha
Androcles
Apr 17, 2012, 3:29:43 PM4/17/12
to
news:wlhjr.5213$kb7....@newsfe20.iad...
Nigers are from Nigeria.
> That's the nuculus of the problem.
That's a Heath Robinson variation on homunculus.
>
> Irregardless?
Carelessly watering the garden, the driveway and the fence,
you spelt it wrongly... "irrigardless".
>
> Jerry
> --
> Engineering is the art of making what you want from things you can get.
I just did.
> On 4/16/2012 5:08 AM, Androcles wrote:
>> "Jerry Avins"<j...@ieee.org> wrote in message
>> news:IiMir.1281$M37...@newsfe01.iad...
>>> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>>>
>>> ...
>>>
>>>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>>>> jerry rigs.
>>>
>>> I resent that. The word is "jury rig".
>>>
>>> ...
>>>
>>> Jerry
>>
>> As a lurker trying to decide who is correct I see myself as
>> a juror. I have not been rigged, it seems more like a jerry
>> rig to me.
>
> It takes a long time for a frequent error to become accepted as correct:
>
> Aks me no questions and I'll tell you no lies.
>
That's Niger talk.
>> "Jerry Avins"<j...@ieee.org> wrote in message
>> news:IiMir.1281$M37...@newsfe01.iad...
>>> On 4/15/2012 11:20 AM, Bret Cahill wrote:
>>>
>>> ...
>>>
>>>> Mathematicians, however, aren't satisfied with "well it woOOorks"
>>>> jerry rigs.
>>>
>>> I resent that. The word is "jury rig".
>>>
>>> ...
>>>
>>> Jerry
>>
>> As a lurker trying to decide who is correct I see myself as
>> a juror. I have not been rigged, it seems more like a jerry
>> rig to me.
>
> It takes a long time for a frequent error to become accepted as correct:
>
> Aks me no questions and I'll tell you no lies.
>
Nigers are from Nigeria.
> That's the nuculus of the problem.
>
> Irregardless?
Carelessly watering the garden, the driveway and the fence,
you spelt it wrongly... "irrigardless".
>
> Jerry
> --
> Engineering is the art of making what you want from things you can get.
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