Before revision: If ω1 and ω2 are the lower and upper frequency points (respectively) of the bandpass response corresponding to ωc ' of the prototype, then, and Δω is the absolute bandwidth, and ω0 is the resonant frequency of the resonators in the filter.
After revision: If ω1 and ω2 are the lower and upper frequency points (respectively) of the bandpass response corresponding to ωc ′ of the prototype, then, and Δω is the absolute bandwidth, and ω0 is the resonant frequency of the resonators in the filter.