Monolithic Millimeter Wave Impatt Transmitter

GaAs IMPATT diodes are commonly used as the power source in millimeter wave transmitters. The power performances of IMPATT diodes are unmatched by any other solid1 state device at high frequencies, therefore IMPATT diodes in general and GaAs IMPATTs in particular fulfill the needs of such systems for high power and high efficiency. Conventionally, IMPATTs are used as discrete devices in hybrid circuits to maximize their output. More recently, monolithic circuits containing IMPATT diodes have also become available[l,2] The capability of integrating IMPATTs with passive circuit elements on a single-chip creates the possibilities of realizing more complex yet compact monolithic subsytems at frequencies extending into the mm-wave region. One example of such an integration is the fabrication of oscillators and radiating elements of a phased array system in a monolithic form. In such a system, each radiating element is fed by its own power source eliminating the need for a complex and lossy power distribution network.