Rigorous Design Method for Symmetric Reflectionless Filters with Arbitrary Prescribed Transmission Response

In this article, we present a novel generic reflectionless filter topology that can produce an arbitrary predefined transmission response while having the perfect impedance matching at both ports. A detailed procedure for synthesizing reflectionless filters using our topology is also given in this article. One of the unique features of our reflectionless filter topology is that the even- and odd-mode half circuits are not correlated with each other, which makes the filter synthesis straightforward. Hence, the synthesis procedure does not necessitate using either an optimization technique or a numerical method. This article also presents a methodology for transforming a generic topology into a practical one with a reduced number of elements. The presented filter topology and design parameters have been verified by designing lowpass and bandpass filters.