Radio frequency antenna for wearable device

Abstract

Data about concentration of one or more types of molecules present within a human body are determined noninvasively using radio frequency signals. These signals at several different frequencies are generated at very low power levels are emitted and acquired using an antenna mounted to a wearable device. Information about changes to the signals, such as phase variances of the signals at different frequencies is indicative of the concentration of one or more types molecules within the user. The antenna includes concentric elements with one or more being used to emit the signal(s) while one or more are used to acquire the signal(s). Concentrations at different depths may be measured by selectively using particular concentric elements. A maximum depth may approximately equal the spacing between the elements being used at a given time. Other sensors may be emplaced or operate through windows located between one or more of the concentric elements.