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Design >> RF Design >> Bandwidth of oscillator without input
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Message started by hesan on Nov 13^th, 2013, 7:23am

Title: Bandwidth of oscillator without input
Post by hesan on Nov 13^th, 2013, 7:23am

How to compute bandwidth of oscillator for LC-Cross Coupling oscillator ?
In My design Oscillator,I remove Varactor Mos for tuning Bandwidth and I want to calculate bandwidth of Oscillator.you now this oscillator dont have input and for this reason I dont Know How to measure Bandwidth.
If you have any idea for this work please explain How do it with ADS simulator? :'(

Title: Re: Bandwidth of oscillator without input
Post by aaron_do on Nov 21^st, 2013, 5:47pm

Hi,

what do you mean by the "bandwidth of your oscillator". If it doesn't have a tuning cap, then it only has one oscillation frequency.

regards,
Aaron

Title: Re: Bandwidth of oscillator without input
Post by hesan on Nov 25^th, 2013, 3:01am

Oscillation frequency and bandwidth are different.

Oscillation frequency of my oscillator is clear to me, But I do not know that bandwidth ranges.

for example oscillation frequency of on oscillator is 2.4GHz and Bandwidth it is 400 MHz. range of bandwidth : [2GHz,2.8GHZ].

Note that the oscillator has no input, please help me in the measurement bandwidth. :'(

Title: Re: Bandwidth of oscillator without input
Post by aaron_do on Nov 25^th, 2013, 4:32am

Quote:

for example oscillation frequency of on oscillator is 2.4GHz and Bandwidth it is 400 MHz. range of bandwidth : [2GHz,2.8GHZ].

I still don't get what you mean...I'm sure you are not talking about phase noise. Maybe you are talking about the bandwidth of your LC tank? i.e. just the L and (C + parasitics), but not including the -ve impedance...then its just f0/Q...

Aaron

Title: Re: Bandwidth of oscillator without input
Post by hesan on Nov 25^th, 2013, 7:07am

thanks Aaron. ;)