A system for monitoring a health parameter in a person is disclosed. The system includes a frequency synthesizer configured to generate radio waves across a range of stepped frequencies, at least one transmit antenna configured to transmit the radio waves below the skin surface of a person, a two-dimensional array of receive antennas configured to receive radio waves, the received radio waves including a reflected portion of the transmitted radio waves, processing circuits configured to generate data that includes amplitude and phase data in response to the received radio waves, and means for determining a value that corresponds to a health parameter of the person in response to the amplitude and phase data.
