A Radio-frequency High-Q System for Biomedical Sensing Applications

In this paper, a preliminary analysis of a near-field radiating system for biomedical sensing applications by using a radio-frequency magnetic field is presented. The proposed system, operating at 50 MHz, consists in a resonant helical coil wrapped around on a ferromagnetic core and inductively coupled with an unloaded probe loop. The system design has the main purpose to produce a focused magnetic field distribution, and, consequently, to guarantee a good spatial resolution of the sensing device. In addition, the introduction of the ferromagnetic material allows to improve the device detection sensibility at the operating frequency, by significantly enhancing the nominal helical coil inductance, thus optimizing the coil Q-factor. The main advantages of the proposed non-invasive system, beside the relatively low-complexity instrumentation, also include the possibility to reducing the health risks associated with the present diagnostic techniques, as the X-rays. The preliminary numerical results suggest the feasibility for an innovative near-field clinical device, for non-invasive sensing applications, as malignant inclusions detection; further analysis is therefore encouraged.