Tables of Chebyshev impedance–transforming networks of low-pass filter form

Abstract

Tables of element values are presented for lumped-element Chebyshev impedance-transforming networks, as are tables giving the Chebyshev passband ripple of each design. These circuits consist of a ladder network formed using series inductances and shunt capacitances; they give a Chebyshev impedance match between resistor terminations of arbitrary ratio (designs with resistor termination ratios from 1.5 to 50 are tabulated). The responses of these networks have moderately high attenuation at dc (the amount of attenuation depends on the termination ratio); their attenuation then falls to a very low level in the Chebyshev operating band, and then rises steeply above the operating band in a manner typical of low-pass filters. Designs having operating-band fractional bandwidths ranging from 0.2 to 1.0 are given. These impedance-transforming networks can be realized in lumped-element form for low-frequency applications, and in semilumped-element form (such as corrugated waveguide) at microwave frequencies.