Hilbert Transform problems
- To: mathgroup at smc.vnet.net
- Subject: [mg73851] Hilbert Transform problems
- From: rob <robIV at piovere.com>
- Date: Fri, 2 Mar 2007 06:26:07 -0500 (EST)
Hi, I'm wondering if someone can help me produce a useful result on the Hilbert transform of what I call a wideband wavelet. I got the basic HilbertTransform definition off the Wolfram site. It seems to me the transform of this wavelet exists (it becomes a symmetrical wavelet) but I can only get a very spiky result where the true result can barely be seen under the noise. The procedure seems to be having all kinds of problems dealing with singularities. I added the Method->Oscillatory because without it, the result appears to be only noise. I've tried all kinds of Methods and other options but none have helped - most make it worse. I'd like to say that in the past I have received many very helpful things here but when I try to repost a reply with thanks and explanations, I never see it posted. But sometimes a new posting does make it. Please let me post my thanks here in advance. My current best code with all converted to "Input Form" is below. (Why my notebook does not put my entries in Input Form -they are in Standard Form --I've never figured out.) 5.1 for Microsoft Windows (January 27, 2005) HilbertTransform[f_, x_, y_, (assum___)?OptionQ] := Integrate[f/(x - y), {x, -Infinity, Infinity}, Method -> Oscillatory, PrincipalValue -> True, assum]/Pi w = 5.; a = 1.; s[t_] := Sin[w*t]*Exp[-(t/a)^2]; Plot[s[t], {t, -10, 10},PlotRange->All] f[y_] = HilbertTransform[s[t], t, y] Plot[f[x], {x, -3, 3}] (for email, remove the IV)