Modified Chebyshev bandstop filter with transmission zeros at real frequencies

The logarithmic periodic transmission line filter has been shown to be an attractive alternative to elliptic function filters when a high rate of cutoff is needed.In this article, it is shown that an improved passband and bandedge response can be obtained if impedances obtained from a Chebyshev prototype are used, and the stopband width increased by shifting the resonant frequencies of the stubs away from the centre frequency in a non‐periodic fashion.