VECTOR SAR

Projet Completed
European Projects

Project duration

Fin du projet 2020
  • Project objectives

    The overall goal is to develop traceable measurement and characterization methods for the European telecommunication industry. The goal is also to support a sustainable approach guaranteeing the highest quality of measurement standards in line with the CEI 62209-3 standard, currently being developed by IEC TC 106: “Methods for the assessment of electrical, magnetic and electromagnetic fields associated with exposure to humans.”
    The CEC (European Consumer Centre) will focus on the metrology research required to support the standardization of SAR measurement, using vector probes.

  • Search axes
    1. Developing traceable methods for the calibration of probes in the temporal domain and of probe networks up to 6 GHz. Added to which is to check the accuracy of these measurement systems after calibration and identify the associated sealed ghost properties.
    2. Establishing uncertainty propagation using multivariate models, drawing on the principles stated in the “Guide for Uncertainty in Measurement” (GUM). The idea is to identify sources of uncertainty in measurement, together with its propagation via multivariate transformations, and to implement a system of single-vector probe to be used in scanning systems.
    3. Checking the reliability of measurement systems for a wide range of emitters and improving telecommunication signal measurement and SAR measurement for a wide range of devices. This should include setting up a better processing system for the data used, with probes in the temporal domain.
    4. Developing test protocols for MIMO and modular devices, using vector probe networks to establish the highest SAR value (worst case) with a combination of MIMO signals.
    5. Making it easier to adopt the measurement systems developed and contributing to the development of IEC TC 106 standards on the successfully adopted IEC 62209-3 relating to vector-based SAR measurement systems in Europe. In addition, ensuring that the project’s output is aligned with the IEC CT 106 requirements, in a form that can be incorporated into the standards as soon as possible.
  • Results

    Expected results

    SAR calibration methods with individual probes are well established in IEC 62209-1 and 2 standards and provide a range of calibration uncertainty of around 10% at k = 2. However, these methods cannot be applied to sensor networks, mainly because of the latter’s physical size and they do not calibrate the phase measurement for the vector probe, which is key to the accuracy of reconstruction on the ground. The fact is that the entire range of sensors is performing well, which cannot be ascertained on the basis of individual sensors. This is why the IEC is developing a new IEC62209-3 standard to formalize SAR measurements with vector probes. This has however highlighted the challenges posed by establishing traceability and analyzing uncertainty for vector-based measurement systems. As a result, we currently rely on the validation of SAR measurement thanks to reference sources. Although this suits a small range of existing devices with reference sources, no new devices are being developed (with no new reference sources either).