The problem is to recover the coupling parameters of a microwave filter from scattering measurements.
We propose an indentification method in two steps
- a stable and causal model of high degree is first computed from the data (completion stage); In the first stage the most is made of the data taking into account the expected behavior of the filter
- a stable reduced order model is then computed by RARL2
The whole process is performed by the software PRESTO-HF. The results of our procedure are shown at hand of a real-life example provided by the CNES. It consists of measurements of a microwave filter of 8th order in 800 frequency points. An excellent agreement is obtained between the final rational model and the measurements. The latter is obtained in less than 15 seconds on a Intel Core I7 processor, which makes our approach compatible with a real-time tuning procedure of the filter.
The software PRESTO-HF is currently used for this purpose by several of our industrial partners.
The coupling parameters are finally extracted from the identified model. This step is performed by the software DEDALE-HF.