Systems, contact lenses and methods that facilitate antenna communication via sensor impedance modulation are provided. In one aspect, a system can include a contact lens and a radio frequency (RF) reader. The contact lens can include a substrate an RF antenna, disposed on or within the substrate and a sensing component, disposed on or within the substrate, and directly coupled to the RF antenna, wherein the RF antenna is configured to change impedance value as a sensed value of the sensing component changes. The RF reader is external to the contact lens, and configured to interrogate the RF antenna with an RF signal. The RF reader can receive a reflected RF signal from the RF antenna in response to the interrogation. The magnitude, phase and/or a frequency of the reflected RF signal can be based on the impedance value of the RF antenna.
