Microwave Journal
www.microwavejournal.com/articles/9545-nmdg-speeds-up-component-characterization

NMDG Speeds Up Component Characterization

May 20, 2010

NMDG announced that accurate source- and load-pull characterisation of active components or circuits is speeded up and simplified with the new NM600 Fast Source- and Load-pull (FSLP) application.

Using a vector network analyzer (VNA) with two internal RF sources at its full power, the new NMDG FSLP application enables the characterisation of active components under various input and output mismatch conditions. Within the power capabilities of the VNA, one does not need to invest in a dedicated and costly source- and load-pull setup, based on either passive or active tuning techniques. As such, the NM600 FSLP is a low-cost source- and load-pull solution. When required, the power capabilities can be further extended using external amplifiers and some accessories such as isolators and possibly external couplers.

Running directly on selected VNAs, the NM600 FSLP application allows capturing the fundamental behaviour of active components or circuits quickly, in terms of incident and scattered voltage wave at both ports, under any input and output load conditions. First, the behaviour of the component is saved for a selection of bias points, fundamental frequencies, input powers and output load impedances. Next, different derived quantities, such as power gain, delivered input and output powers or power added efficiency (PAE), can be visualized versus input and output mismatch conditions. This empowers RF engineers to easily obtain the optimal source and load matching network parameters to interface two different stages, using a minimal number of iterations.

Moreover, the NM600 FSLP application performs the necessary measurements to derive a fundamental S-functions model. Coupled in commercially available simulators, such a model will allow to predict the behaviour of active components or circuits at fundamental frequency under varying source and load conditions or in interaction with other components, assuming the effect of harmonics can be neglected.