No abstract

Dielectric properties of matter are a key fact on substance characterization processes. Usually, these are evaluated by means of high energy excitations that could even destroy the sample, depending on the system used. This kind of systems require very expensive, bulky and fragile instrumentation devices, lacking portability and requiring specifically trained technicians for its operation.This Thesis shows a liquid phase chemical solutions characterization system, based on contactless ultra-wideband low power electromagnetic excitations. It is a low cost, portable, compact -implies near field operation-, non destructive analysis device and, also, it does not require highly skilled personal to be used. Thus, it is specially suited for field and adverse environment operation, being an alternative to traditional measuring devices.The core of this work is about the design of the physical system itself, so it involved the design and development of a transmitter-receptor pair to do the sample under test measurements. The sample is placed under a mechanically determined geometry, in order to achieve a high repeatability.An auto-calibrated, differential substance characterization methodology has been developed too. By means of this, it is possible to attenuate some of the issues related to compound quantification estimation in mixtures. This method also allows to compare measurements between different devices and along time, if all the general environment conditions are maintained.The system employs Software Defined Radio -SDR-technology, due to the high flexibility on complex waveform receiving and transmitting. As an additional advantage it is easy to find in the market at a low cost. Due to SDR are not designed