Some prominent aspects of the inverse Chebyshev functions

It is shown that, given the magnitude specifications in the passband and stopband, the inverse Chebyshev functions require the identical order n as the Chebyshev counterparts. The phase and time-delay characteristics of the inverse Chebyshev functions as compared to Chebyshev functions are investigated. Unlike the Chebyshev or elliptic filters, the inverse Chebyshev functions possess the maximally flat magnitude at DC, and it decreases monotonically throughout the passband. This fact implies that the phase and time-delay characteristics of the inverse Chebyshev functions must be preferable to those of the Chebyshev functions