Computer-aided design of microwave amplifiers by the random addition of new components

A new technique for the optimisation of microwave transistor amplifiers has been developed, whereby the computer program removes components or adds new components and nodes to the circuit, in a systematic but apparently random manner, in order to approach specified performance targets. Although the assessment of a large number of possible alternative circuits consumes a large amount of computer time, two examples show that acceptable circuits are produced with very little operator interaction. The program optimises for gain, noise figure, input and output VSWR and stability. It is suitable for integrated circuit design. Examples are given of a single-stage amplifier with feedback and a two-stage amplifier with lossy matching networks but without feedback operating over the frequency band 8¿¿12 GHz.