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Tony's Intertwingled Memex • Reference Manual

RLC Circuit Dynamic Filter Transfer (Electrical Engineering)

Formulas & Definitions

An electrical communications engineer is designing a bandpass signal conditioning filter for a radio frequency telemetry receiver. The normalized output voltage gain H(ω)H(\omega)H(ω) as a function of the angular frequency ω>0\omega > 0ω>0 (in krad/s\text{krad/s}krad/s) is described by the rational transfer function:

H(ω)=10ωω2+25H(\omega) = \frac{10\omega}{\omega^2 + 25}H(ω)=ω2+2510ω​

  1. Apply the Quotient Rule using a formal Component Dictionary (u,u′,v,v′u, u', v, v'u,u′,v,v′) to find the frequency derivative dHdω\frac{dH}{d\omega}dωdH​.
  2. Simplify the numerator of the derivative by expanding and combining like terms.
  3. Determine the cutoff frequency ω∗\omega^*ω∗ where the rate of gain change is zero (dHdω=0\frac{dH}{d\omega} = 0dωdH​=0), corresponding to the resonance peak of the bandpass filter.