Use of picosecond optical pulses and FET's integrated with printed circuit antennas to generate millimeter wave radiation

Millimeter-wave radiation has been generated from field effect transistors (FETs) and high electron mobility transistors (HEMTs), integrated with printed circuit antennas and illuminated with picosecond optical pulses. Modulation of the millimeter waves was achieved by applying a swept RF signal to the transistor gate. Using this technique, tunable electrical sidebands were added to the optically generated carrier providing a method of transmitting information. The technique also provides increased resolution for use in spectroscopic applications. Heterodyne detection demonstrated that the system continuously generated tunable radiation, constrained by the high-gain antenna, from 45 to 75 GHz.<
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