2. Computer-aided design (CAD)

The quest for ever more efficient hybrid or integrated microwave circuits is leading to ever greater complexity for the designer. Indeed, the grouping of multiple functions on a single small circuit makes it essential to study the interactions between elements beforehand. As measurements inside a microwave circuit are difficult, only numerical simulation can provide the information needed for its dimensioning. These digital simulation techniques are grouped together under the name of CAD: they comprise the following logically interwoven steps:

• initial definition of the circuit based on the specifications;

• analysis of its operation using models of its elements and components;

• comparison between calculated and desired performance ;

• analysis...