Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

How can linear phase shift give undistorted output?

Status
Not open for further replies.

A.Anand Srinivasan

Advanced Member level 5
Joined
Oct 15, 2005
Messages
1,804
Helped
257
Reputation
514
Reaction score
39
Trophy points
1,328
Location
India
Activity points
10,680
i studied that linear phase shift ensures undistorted output how is that possible when each frequency is shifted differntly
 

electronics_kumar

Advanced Member level 2
Joined
Nov 29, 2004
Messages
659
Helped
34
Reputation
68
Reaction score
9
Trophy points
1,298
Location
Tamilnadu
Activity points
5,552
Re: linear phase shift

linear phase shift means same phase shift for all frequency of the signal which is equal to delay in time domain ie we will get the output after delay
If it is nonlinear means in the frequency domain it will produce different phase shift for different frequencies of same signal which when displayed in time domain ,we will get a distorted signal..
hope it helps
 

Kral

Advanced Member level 4
Joined
Mar 28, 2005
Messages
1,326
Helped
280
Reputation
558
Reaction score
85
Trophy points
1,328
Location
USA
Activity points
13,417
Re: linear phase shift

A.Anand Srinivasan,
Linear phase shift means that the phase shift varies linearly with frequency. Under these conditions, a signal that conatins multiple frequencies (such as a pulse) will be delayed in time, but not distorted. Visualize a wave that consists of a fundamental and a third harmonic. If the phase shift of the third harmonic is exactly three times the phase shift of the fundamental, then the phase shifted output waveform will be undistorted. Try drawing this or plotting this in Excel. It is not possible to obtain perfect phase linearity in an analog system, but it can be attained digitally. Simply run the sampled signal through a FIR filter whose coefficients are symmetrical with respect to the middle coefficient. This guarantees perfect phase linearity.
Regards,
Kral
 

Status
Not open for further replies.
Toggle Sidebar

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top