Novel lossy microstrip filter with extracted-pole technique

This paper presents a novel lossy six-pole microstrip bandpass filter using extracted-pole technique that shows good performance of high selectivity and flat insertion loss in the passband. The high selectivity is achieved by introducing two transmission zeros using two extracted poles and the flat passband is contributed by the resistive cross coupling in the in-line network. Theoretical modelling, full-wave electromagnetism simulation and experiment have showed promising results for further development.