Reflectionless Butterworth and Chebyshev Filters

A general network can be made reflectionless by connecting a complementary network in parallel that sums to match the constant source conductance. The realizability of the complementary network can be guaranteed in general by ensuring that the complementary admittance is positive real. The reflectionless second-order Butterworth, Chebyshev, and the inverse-Chebyshev filters are synthesized and simulated to be reflectionless at the input port.