Multi-resonant perturbation method for capacitive sensing with composite right/left-handed transmission lines

The possibility to use the left-handed capacitances of a composite right/left-handed (CRLH) transmission line for a capacitive sensor array is demonstrated. The capacitances values are extracted with the presented algorithm that is based on a multi-resonant perturbation technique. The CRLH line structure was chosen since its physical implementation is much better suited to a capacitive sensing transmission line than a right-handed (RH) one. In contrast to other techniques like time domain reflectometry single cell spatial resolution can be achieved with moderate bandwidth demand. Presented numerical and experimental results prove the concept.