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help on frequency formula

Discussion in 'General Electronics Chat' started by joe99641, Nov 11, 2007.

  1. joe99641

    Thread Starter New Member

    Nov 9, 2007
    Could somebody out there help with this, I am trying to figure out what the following letters stand for in this formula, they are Wc, s, j ; the formula is
    LP=Wc^4/(Wc^2+1.414*Wc*s+s^2)^2 I also have the following information
    Wc=j*2*pi*Fc, Fc=crossover Frequency, s=j*2*pi*F, F=frequency in Hz.
    Any comments would be appreciated, Thanks
  2. hgmjr

    Retired Moderator

    Jan 28, 2005
    the W is actually the greek letter omega \omega

    \omega = 2\pi*f where f equals frequency.

    \omega_{c} Most likely this is being used to represent the corner frequency of a filter.

    The variable s = j\omega

    LP stands for lowpass. This indicates to me that the expression you have is the transfer function for a lowpass filter.

    Further to my earlier comments, the coefficients that appear in the denominator of the expression would lead me to conclude that the expression is for a 2-pole Butterworth Low Pass filter.

  3. joe99641

    Thread Starter New Member

    Nov 9, 2007
    Thankyou,this is most helpful.