94 GHz Monolithic Transmitter for Weather Radar Application

This thesis was written for concluding my studies at the University of Padua. The main topic is the design of a monolithic transmitter in SiGe bipolar technology, for weather radar application at an operating frequency around 94GHz. At such a high frequency parasitic elements have to be taken into account very carefully. Appropriate matching networks become important to allow the signals to pass across the different ections of the transmitter, without reflections or attenuations. To this aim, transmission lines were used instead of inductors, in order to save size and to have a more reliable modelling of device parameters and parasitic elements. The structure of the transmitter includes a transformer (which acts as Balun), a frequency quadrupler and a buffer. The transmitter input receives a single-ended reference signal at 23.5GHz, with a power of 0dBm on a single-ended input impedance of 50Ω. The output has been designed for a differential load of 100Ω and to operate in the temperature range of 0°C - 100°C, with a typical output power above 10dBm and spurious harmonic below -25dBc