A Low Conversion Loss Design Method of F-Band Fundamental Mixer

In this paper, a low conversion loss design method of F-band fundamental mixer is simulated and verified. At the radio frequency (RF) end, the series diode is directly installed on the narrow side of the reduced waveguide to realize the conversion from unbalanced to balanced structure. This method reduces the transmission loss of the planar dielectric and is easy to achieve broadband impedance matching. The local oscillator (LO) probe and intermediate frequency (IF) filter cover the full F-band to ensure the wideband characteristics of the mixer. The whole circuit is fabricated on a 127 μm quartz substrate. The test results show that the minimum conversion loss changes in the range of 4.3 dB and 7 dB within the full F-band, with a LO power level of 13~15 dBm and an IF of 100 MHz.