A novel ultra-broadband DC-36-to-66-GHz hybrid diplexer using waveguide and SSL technology

This paper describes a novel wideband low-loss contiguous diplexer with steep band selectivity achieved by combining a planar suspended stripline (SSL) and waveguide filter. The diplexer is comprised of an input circuit configured to receive a broadband signal, a low-pass filter (LPF), and a highpass filter (HPF) and covers DC 36 to 66 GHz. The LPF is implemented using a planar transmission line. The HPF is implemented using a waveguide and is connected to the LPF using a SSL-to-waveguide transition.