| Quasi-optical grid amplifiers and oscillators have been limited in power to less than a watt at Ka-band until recently. Additionally, measurements of grid structures have been done with fax-field techniques, making reflection measurements difficult. Some focused techniques have been used as well. Here are presented a 5-watt grid amplifier at 37.2 GHz, and a grid oscillator, after Moonil Kim, that shows 1 watt of effective transmitter power at 38 GHz. Focused beam measurement techniques are also discussed, introducing a new method to calibrate a network analyzer for reflection measurements. Measurements are presented on passive structures to validate the calibration technique, and then measurements of the active structures are presented.;Following the presentation of the 5-watt amplifier and 1-watt oscillator, a design technique for a 10-watt grid amplifier is presented, along with a mode converter that allows the grid to be fed from a standard waveguide port. |
