1. Physics Department , Federal Institute of Metrology METAS , Bern-Wabern , Switzerland
2. RISE Research Institutes of Sweden , Borås , Sweden
3. Metrology Department , IPQ , Caparica , Portugal
4. UNIDEMI, NOVA School of Science and Technology , Caparica , Portugal
5. Department of Electrical and Electronic Engineering , University of Strathclyde (UoS) , Glasgow , UK
6. Danish Technological Institute (DTI) , Aarhus C , Denmark
7. Medical Sensors and Devices Lab , Technische Hochschule Lübeck (THL) , Lübeck , Germany