Exploitation of active load-pull and DLUT models in MMIC design

The use of active load-pull techniques in the design of high efficiency microwave amplifiers has been well documented. This paper describes how it has been applied to the design of a wideband RFIC gain stage. The technique is particularly relevant in new and developing processes where accurate device models are not available and designers otherwise are often forced to use multiple iterations of a design to attempt to encompass the variability in the process. Often in RFIC design, components operate outside of the ideal operating impedance. A look-up table model technique based on measured data which can be used by conventional CAD programs is used to analyse behaviour. This paper shows how the design process and capabilities of the system can be combined to improve the cost effectiveness and performance of RFIC development and with a stable manufacturing process a “first pass” design methodology. The use of the measurement system as an analysis tool is described.