Doubly balanced diode mixer comprising a ring modulator each leg of which comprises a high speed conventional diode in series with at least one diode of the "varactor" kind

A double balanced mixer comprising:

• i--a four leg ring modulator having four identical rectifying legs with each leg comprising a high speed diode connected in series with at least an additional diode different from said high speed diode and having an intrinsic resistance of the same order of magnitude as that of a perfect junction and with an accumulated charge of at least several nanocoulombs;
• the respective high speed diodes and additional diodes of the respective legs being arranged in a common current flow direction around the four leg ring modulator and four ring modulator terminals being each positioned between two of the said legs;
• ii--a first signal input transformer having a primary winding and a balanced center tapped secondary winding with opposite terminals connected to a first opposite pair of said ring modulator terminals;
• iii--a second signal input transformer having a primary winding and a balanced center tapped secondary winding with opposite terminals connected to a second opposite pair of said ring modulator terminals;
• and
• iv--a pair of output terminals connected to the respective center tappings of the secondary winding of the respective first and second input transformers.