Implicit space mapping method for dual-band filter and wideband diplexer design

In this paper, open-stub loaded resonator and short-stub loaded resonator are adopted to design a novel wideband diplexer and dual-band filter. To accelerate simulation speed, implicit space mapping method is firstly applied in multi-mode filter and diplexer design. To demonstrate it, a novel dual-band filter with central frequency at 1.8/2.5GHz and relative bandwidths of 16.7%/12%, and a diplexer with central frequency at 1.9/2.5GHz and relative bandwidth of 30%/24% are designed and fabricated and the measured S-parameters agree with the simulated one.