Filters Explained: What Are DSP Filters?

  • Thread starter Thread starter blackout77
  • Start date Start date
  • Tags Tags
    Filters
AI Thread Summary
Digital Signal Processing (DSP) filters are tools used to manipulate signals by allowing or blocking certain frequency components. Lowpass filters permit frequencies below a specific cutoff, while highpass filters allow frequencies above it. Bandpass filters only let through frequencies within a defined range, and stopband filters block frequencies within a certain band. FIR filters have a finite response to impulses, while IIR filters can have an infinite response, potentially leading to oscillations. Understanding these filters is crucial for effectively processing and analyzing signals in various applications.
blackout77
Messages
6
Reaction score
0
Filters what are they??

Can someone explain to me what are filters (DSP) in plain english? Fir filter, IIR filter,... Chebyshev, Butterworth,... Bands (stop, pass, lowpass, highpass).
 
Engineering news on Phys.org


http://www.dspguru.com/info/terms/filtterm/index.htm
 
Last edited by a moderator:


Is this homework?

- Warren
 


Nope, I just couldn't find a good explanation of what they are without getting into so much technicality.
 


Every signal can be described as a sum of sinusoids with different frequencies. Simply put, filters can block certain frequencies in your signal. So for example, a low pass filter would block out the high frequency components of the signal.
 


blackout77 said:
Can someone explain to me what are filters (DSP) in plain english? Fir filter, IIR filter,... Chebyshev, Butterworth,... Bands (stop, pass, lowpass, highpass).

A "band" is a range of frequencies.

A lowpass filter passes all signal components with less than some critical frequency, called the cutoff frequency.

A highpass filter passes all signal components with greater than some cutoff frequency.

A bandpass filter passes only signal components within some band.

A stopband filter stops only signal components within some band.

FIR filters have a finite-duration impulse response. If you put an impulse (a signal that is zero everywhere except a very brief interval of time) into an FIR filter, the response will eventually die down to zero and stay there forever.

IIR filters have (potentially) infinite-duration impulse response. The output of an unstable IIR filter will oscillate forever in response to an impulse.

A Butterworth filter is a monotonically-decreasing filter with maximal passband flatness. Its frequency response gently decreases in amplitude with increasing frequency. It is a very easy-to-understand filter.

A Chebyshev filter is not monotonically-decreasing, and trades flatness in either the passband or stopband for a narrower transition between passband and stopband.

- Warren
 
Very basic question. Consider a 3-terminal device with terminals say A,B,C. Kirchhoff Current Law (KCL) and Kirchhoff Voltage Law (KVL) establish two relationships between the 3 currents entering the terminals and the 3 terminal's voltage pairs respectively. So we have 2 equations in 6 unknowns. To proceed further we need two more (independent) equations in order to solve the circuit the 3-terminal device is connected to (basically one treats such a device as an unbalanced two-port...
suppose you have two capacitors with a 0.1 Farad value and 12 VDC rating. label these as A and B. label the terminals of each as 1 and 2. you also have a voltmeter with a 40 volt linear range for DC. you also have a 9 volt DC power supply fed by mains. you charge each capacitor to 9 volts with terminal 1 being - (negative) and terminal 2 being + (positive). you connect the voltmeter to terminal A2 and to terminal B1. does it read any voltage? can - of one capacitor discharge + of the...
Back
Top