Ultra-broadband planar millimeter-wave mixer with multi-octave IF bandwidth

摘要

In some embodiments, a system may include a passive uniplanar single-balanced millimeter-wave mixer. In some embodiments, a three-port diode-tee IC forming a mixer core is coupled between an end of a slotline balun and a second coplanar balun. The operational bandwidth of a mixer structure is enhanced by optimizing the distance between the mixer diode-tee core and the back-short circuits. The frequency separation of LO and IF signals may be accomplished by means of stand-alone three-port filter-diplexer device. The system may allow wider than a frequency octave operational bandwidth for a frequency converter device all the way into millimeter wave frequencies at the same time as supporting the operational bandwidth for baseband IF signal over more than six frequency octaves. In some embodiments, the system may accomplish a 500 MHz to 34.5 GHz continuous IF bandwidth with RF signal sweeping from 33 GHz to 67 GHz and local oscillator at 67.5 GHz fixed frequency.

主权项

1. A system comprising a passive uniplanar single-balanced millimeter-wave mixer comprising:
a metallic mixer housing comprising a first compartment and a second compartment, a dielectric substrate positioned in the first compartment configured to support a first coplanar waveguide, a coplanar-to-slotline transition, a slotline balun, and a second coplanar waveguide electrically connected to feed RF, LO, and IF electrical signals to and from a single-balanced mixer core structure; wherein the first coplanar waveguide is coupled to a first port at a first end and is configured to convey the RF signal to the coplanar-to-slotline transition which is electrically coupled to a second end of the first coplanar waveguide; wherein the coplanar-to-slotline transition is configured to convert the RF signal from an unbalanced common mode into a balanced slotline mode by terminating a first slot of the first coplanar waveguide into a slotline open termination which electrically separates a first and a second metal conductor of opposite electrical polarity forming the slotline balun, wherein a second slot of the first coplanar waveguide terminates into the slotline balun; wherein the first metal conductor of the slotline balun is electrically coupled to a second ground strip metal conductor of the first coplanar waveguide, and wherein the second metal conductor of the slotline balun is electrically coupled to a signal conductor of the first coplanar waveguide; wherein the second coplanar waveguide is coupled to a second port, wherein the second port comprises a broadband coaxial interface; wherein the single-balanced mixer core structure comprises a three-port diode-tee; wherein the distance between the single-balanced mixer core structure and a back-short circuit for RF signal is optimized such that a mixer conversion efficiency over a very wide operational bandwidth is improved.