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The Best Name for Signal Recovery Matched Filtering

Started by Bret Cahill April 19, 2012
On 4/19/2012 2:43 PM, Bret Cahill wrote:
> I just assumed "matched filtering" included the deconvolution and > other steps to recover the original signal's shape. > > In this case it was actually easier to invent a new filter -- I > assumed it already existed -- than to be scholarly and do some > research. > > To avoid confusion with the terminology from now on the filter that > takes the convolution of a noisy signal like a conventional matched > filter and then takes the deconvolution to recover the original wave > form should be called "signal recovery matched filtering." > > This will distinguish it from the signal detection matched filter > _even if the new filter is used for signal detection_. > > I've updated http://www.bretcahill.com to reflect the new terminology. > > If anyone can think of a better name, i.e., the "Cahill Filter" please > post. >
Filtering (convolution) in the time domain is multiplication in the frequency domain, and is therefore associative. If you apply a filter F and its inverse F^-1 to a signal G, F^-1 (F G) = (F^-1 F) G = G. No free lunch, I'm afraid. (I once tried something reminiscent of that to improve loop stability of a PLL. It turned out that I'd made an algebra error, and was in fact trying to make a time machine. It didn't work.) ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Phil Hobbs wrote:
<snip>
> > (I once tried something reminiscent of that to improve loop stability of > a PLL. It turned out that I'd made an algebra error, and was in fact > trying to make a time machine. It didn't work.) ;) >
I've been trying to make a time machine* all week. It's damned difficult, I must say! *In this case, a filter with alpha of 0.001 with no delay. Er rather, a filter plus some other furniture. Or, as it turns out, not. Stupid Second Law!
> Cheers > > Phil Hobbs > > > >
-- Les Cargill
On 06/26/2015 11:08 PM, Les Cargill wrote:
> Phil Hobbs wrote: > <snip> >> >> (I once tried something reminiscent of that to improve loop stability of >> a PLL. It turned out that I'd made an algebra error, and was in fact >> trying to make a time machine. It didn't work.) ;) >> > > I've been trying to make a time machine* all week. It's damned > difficult, I must say! > > *In this case, a filter with alpha of 0.001 with no delay. Er > rather, a filter plus some other furniture. Or, as > it turns out, not. Stupid Second Law!
Gummint has time machines. But they don't much understand how they work. They ship things off into time but they don't come back until much later. They have no idea where they went. -- ___ ___ ___ ___ /\ \ /\ \ /\__\ /\ \ /::\ \ /::\ \ /::| | \:\ \ /:/\:\ \ /:/\:\ \ /:|:| | ___ /::\__\ /::\~\:\__\ /::\~\:\ \ /:/|:| |__ /\ /:/\/__/ /:/\:\ \:|__| /:/\:\ \:\__\ /:/ |:| /\__\ \:\/:/ / \:\~\:\/:/ / \:\~\:\ \/__/ \/__|:|/:/ / \::/ / \:\ \::/ / \:\ \:\__\ |:/:/ / \/__/ \:\/:/ / \:\ \/__/ |::/ / \::/__/ \:\__\ /:/ / ~~ \/__/ \/__/