how to extract the DC component of the sine wave signal

dc component of a signal

how to extract the DC component of the sine wave signal V+V0coswt ??

that is : the input signal is V+V0coswt , when it passes through the system I designed, the output signal is V, or proportianal to V?

one may say a lpf will do this work , but if w is relatively low ,for example in the range of 100Hz ? such a lpf is not easy to design
moreover, this lpf is not a ideal one, so the AC component will remain ,although with small amplitude.

This may be a tough question , sincerely hope you could provide some ideas

many many thanks !!!!!!!

dc component of signal

hi
have you conidered a series of of lpf s rather than one.

regards

dc component signal

Hi
I think that you must design a narrow band filter with 5-10HZ bandwidth.
regards

what is a dc component in a signal

If it where a DSP system I vote for an LMS fitting the DC plus omega and phase over possible a time less than a period of the sine.

If you know the frequency in advance try to use a notch filter. You will get nearly optimum response times for the remaining DC. If there is some mismatch in noth frequency remaining ripple could be lowpass filtered.

what is dc component of a signal

Nimer said:

hi
have you conidered a series of of lpf s rather than one.

regards

Click to expand...

this method may work , I will have a try

Added after 1 minutes:

hr_rezaee said:

Hi
I think that you must design a narrow band filter with 5-10HZ bandwidth.
regards

Click to expand...

design a narrow band lpf is not easy in IC , i think

because large R and C are needed

maybe some special technique may help?

Added after 2 minutes:

rfsystem said:

If it where a DSP system I vote for an LMS fitting the DC plus omega and phase over possible a time less than a period of the sine.

If you know the frequency in advance try to use a notch filter. You will get nearly optimum response times for the remaining DC. If there is some mismatch in noth frequency remaining ripple could be lowpass filtered.

Click to expand...

what is LMS??
i need to design a analog IC filter,not a digital one
the frequecy is about 4000Hz,



thank you for your help !!all of you !!!

signal with dc component

How about passing the signal through a capacitor chain and resistor chain seperately and applying to a differential amplifier???

signal add dc component

how to extract the DC component of the sine wave signal V+V0coswt ??

Click to expand...

Well the signal you've given V + Vocos(wt) cannot be called a "sinewave". If V > Vo then the signal is essentially a DC because the signal then would no longer alternate between ±.

M

extract dc component

Hi
use simple low pass filter with off-chip C and R.
regards

Hey,
I am going with the same problem..........
are your problem solved.........
if yes please help me....................