Improving RF analysis

Sensor Review

ISSN: 0260-2288

Publication date: 1 March 2000



(2000), "Improving RF analysis", Sensor Review, Vol. 20 No. 1.



Emerald Group Publishing Limited

Copyright © 2000, MCB UP Limited

Improving RF analysis

Keywords Spectral analysis

Applicant: Solid State Farms Inc (US)

Patent number: WO9739341

Publication date: 23 October 1997

Title: Improving radio frequency spectral analysis for in vitro or in vivo environments

A specimen containing a chemical of interest as well as other substances is via probes subjected to radio frequency electromagnetic signals having high frequency components extending to perhaps 5GHz. Preferably such frequencies are sequentially presented using one sine wave frequency at a time, although simultaneously presented multiple frequencies may also be useful. Reflected and/or transmitted signal real and imaginary components at the specimen are then spectrally examined as a function of frequency to identify the presence and/or concentration of the chemical of interest. Such examination includes analysis of the effective complex impedance presented by the specimen, and/or effective phase shift between the transmitted and reflected signal at the specimen. In this manner, greater specificity can be attained with respect to detecting presence and/or concentration of a desired analyte or chemical of interest. For in-vitro measurements, a probe is inserted into the specimen and is coupled to a network analyser, or similar electronic system. In such in-vitro measurements, the specimen may include blood or other bodily fluid, or may be a substance unrelated to bodily fluids. In in-vivo measurements, a network analyser or similar electronic system may be coupled to electrode(s) on a probe. The probe is pressed against a subject's body, preferably a finger, and non-invasive analyses are made.