Leadless monitoring of physiological conditions

摘要

A signal representing a physiological condition of a patient is used to modulate an electromagnetic signal received by a transponder so that a modulated electromagnetic signal representative of the signal is re-radiated by the transponder. The transponder includes an antenna and a diode coupled between the antenna and ground. Changing states of a digital signal from an analog-to digital converter that receives an input from a physiological transducer cause the diode to selectively conduct, which causes the impedance of the antenna to change accordingly. The re-radiated electromagnetic signal is demodulated to recover the digital signal, and the output signal of the transducer is recovered and may be displayed to a user and otherwise processed and/or stored.