A Ka Band Satellite Beacon Transmitter

The design and manufacture of a 30 GHz beacon transmitter to be flown on the next generation of AUSSAT satellites is described. The beacon has a transmitter power output of 21 dBm to provide an EIRP of 13.5 dBW minimum over the whole of Australia, with the beam switchable between vertical and horizontal polarisation at a 1 KHz rate. The design is based on frequency multiplication stages from a 34.72 MHz crystal source and uses packaged transistors in all stages. The final FET doubler stage from 15 to 30 GHz utilises a novel combination of microstrip and coaxial technologies to obtain the specified output level and stability for an in-orbit life of at least 12 years, under significant constraints on size, weight and power consumption.