The mixer using a Schottky-barrier diode (silicon) and a microstrip line useable in the frequency band of 11.7-12.2 $GH_z$ with the IF band of 0.96-1.46 $GH_z$ is designed and fabricated. The mixer diode is represented by a nonlinear conductance g and a nonlinear junction capacitance $C_j$. Accounting these nonlinear parameters, the conversion loss of single-ended mixer with image recovery filter circuit is calculated as low as 5 dB.
The optimum local oscillator power level for such a low conversion loss is and several characteristics of the designed mixer are estimated by computer simulation.
Characteristics of the directional coupler and the filter are measured.
