A balanced diode grid mixer

We report the first results from a planar 16-element balanced quasi-optical diode mixer grid. Each unit cell contains four Schottky diodes arranged in a quad bridge configuration. We report a conversion loss of 14 dB at an RF frequency of 3.44 GHz, an IF frequency of 340 MHz, and an incident LO power of 7.3 /spl mu/W per diode. We report a third-order intercept of 4.7 dBm. Antenna pattern and polarizer tuning curves are presented, and our results are compared with theoretical predictions.