A new planar double-double balanced MMIC mixer structure

Coplanar waveguides, slot lines, and coplanar strips are combined to realize a MMIC (monolithic microwave integrated circuit) double-double balanced mixer (DDBM) in which all circuitry is on the top side of the substrate and no via holes are required. The DDBM exhibits RF, LO (local oscillator) and IF (intermediate frequency) bandwidths of 6-20 GHz, 8-18 GHz and 2-7 GHz, respectively, with conversion loss ranging between 6.2 and 9.8 dB, and RF to IF, LO to IF and LO to RF isolations all greater than 20 dB. The mixer was designed analytically using the harmonic balance method to assess key performance parameters.<
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