Ultra broadband non-planar DC-67–100GHz contiguous diplexer implemented on organic liquid crystal polymer (LCP)

This work describes an ultra-wideband low loss contiguous diplexer with steep band selectivity. By combining planar Suspended Stripline (SSL) and waveguide filter enhanced performance in terms of frequencies, cross over loss and bandwidth is reported up to 100 GHz for the first time [1]. The diplexer is comprised of an input circuit configured to receive a broadband signal, a planar low-pass filter, and a waveguide high-pass filter with cross-over at 67 GHz. The low-pass filter (LPF) is implemented using a planar transmission line. The high-pass filter (HPF) is implemented using a waveguide and is connected to the LPF using a SSL to waveguide transition.