The present invention provides a new non-invasive technique for organ, e.g., heart and lung, monitoring. In at least one embodiment of the invention, a subject is radiated with a non-harmful and relatively low power electromagnetic source diagnostic signal normally associated with a communications protocol such as, but not limited to a version of the IEEE 802.11(x) family of protocols in the 2.4, 3.6, or 5 GHz spectrum bands. After passing through the patient, a return signal is acquired from the patient and compared to the original source signal. The differences between the source and modified signals are then analyzed to monitor the heart, e.g., measure heart rate and detect defects within the heart, and the lung. For example, using Doppler Effect principles, heart rate and motion can be measured from the differences in frequency, phase, and/or wavelength between the source signal and the modified signal reflected back from the heart moving within the patient.
