Dragana Živaljević, Saša V. Nikolić

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New type of nearly monotonic rational function with one pair of zeros on imaginary axis has been proposed. By using these new functions with zeros as a parameter, it is possible to make tradeoff between minimum stopband attenuation and selectivity of the amplitude characteristic. In order to present efficiency of the proposed filter, comparison with allpole filter monotonic in the passband and inverse Chebyshev filter is presented. Also, design example for the seventh order new type lowpass filter is given.


Legendre polynomial, Christoffel-Darboux identity, orthogonal functions, all-pole filters, LC ladder network, lossless networks.

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