Planar balanced mixer/converter for broadband applications

A millimeter wave single balanced mixer comprising:

• a metallic housing;
• an RF input port formed in said metallic housing comprised of a section of waveguide having first and second broadwalls;
• a first microwave integrated circuit card disposed within said section of waveguide;
• said card including a dielectric substrate having a metallized surface, a waveguide to slotline transition formed on said substrate and having a first end juxtapose to said RF port, a slotline transmission section disposed in said surface operably coupled to said waveguide to slotline transition, a coplanar waveguide section formed in said surface and operably coupled to said slotline section, and bandpass filter means formed in said surface and operably coupled to said coplanar waveguide section and having a terminal for connection to a local oscillator input;
• a second microwave integrated circuit card disposed within said metallic housing comprised of a low-pass filter having a first terminal operably coupled to said bandpass filter means and having a second terminal adapted for providing an IF output;
• said coplanar waveguide section including first and second transmission channels formed in said metallized surface;
• and
• first and second diodes connected across said first and second transmission channels, respectively, juxtapose to said slotline section.