Re: LOW-PASS FILTER
- To: mathgroup at smc.vnet.net
- Subject: [mg20775] Re: [mg20710] LOW-PASS FILTER
- From: "Jordan Maclay" <jordanmaclay at quantumfields.com>
- Date: Thu, 11 Nov 1999 00:22:49 -0500
- Organization: Quantum Fields LLC
- References: <199911100517.AAA19589@smc.vnet.net.>
- Sender: owner-wri-mathgroup at wolfram.com
A low pass filter is a device that removes all frequencies below some cut-off frequency from a signal that contains many frequencies. The simplest example would be found in any beginning electrical circuit text, and consists of a capacitor and a resistor. The response of the filter to an applied voltage depends on the fact that the impedance of a capacitor goes as 1/frequency, so that it tends to short the applied signal at high frequencies. A high pass filter, also made from a resistor and capacitor allows the higher frequencies to pass. In your case, if you want to remove the noise using a low pass filter, then you need to add noise that is at a higher frequency than the highest frequency of interest in your signal. There are more complicated filters, but the simplest single pole filter that falls off at 1 db/octave (see EE book) would work fine for you. good luck... Jordan MaclayJordan Maclay Chief Scientist Quantum Fields LLC www.quantumfields.com jordanmaclay at quantumfields.com ----- Original Message ----- From: Stefanos Xefteris <sxef at math.auth.gr> To: mathgroup at smc.vnet.net Subject: [mg20775] [mg20710] LOW-PASS FILTER > Hi all.. > I have currently taken a project on fourier analysis from a professor of > mine > Unfortunately he was very vague about what I have to do. > He just said that I would take a function(periodic) add noise,and then > apply a low pass filter on it to eliminate the noise.The problem is I dont > have a clue about what a low-pass filter is,and he insisted that I should > find it alone..anyway,if anyone has ann appropriate example,I would be > glad if he sent it to me > > > >
- References:
- LOW-PASS FILTER
- From: Stefanos Xefteris <sxef@math.auth.gr>
- LOW-PASS FILTER