Abstract :
The design procedure will be analysed for a reflection type amplifier and a transistor amplifier from a circuit engineer´s point of view. That is to say after an appropriate choice of the active device for the required application, the method of characterization for computer assisted design procedure will be analysed. Essentially an exploration is needed of the impedance or S-parameter in at least 4 dimensions (for the variables, frequency, added power, bias and temperature for instance). The choice of the circuit can then be made by optimization procedures which includes an optimised topographical search. Finally a survey of current possibilities in Avalanche Gunn, Baritt, Tunnel diodes and F.E.T. transistors will be given (noise, power bandwidth intermodulation, etc...) with examples of amplifiers with the latest performances that have been realised in the world for different applications. These include low noise applications for receiver preamplifiers, driver stages and output power stages. This survey will attempt to be as general as possible indicating the different technologies that are currently used with their advantages and limitations.
