An implantable device for measuring biological information of a body is provided, wherein the implantable device includes a receiver for receiving electromagnetic energy and converting the electromagnetic energy into electrical energy a storage capacitor associated with the receiver such that the electrical energy from the receiver is stored in the storage capacitor a biological sensor a processing device and a transmitter, wherein the biological sensor, processing device and transmitter are configured to receive electrical energy from the storage capacitor, and wherein the biological sensor, processing device and transmitter are configured such that when the receiver is receiving electromagnetic energy, the biological sensor, processing device and transmitter are inactive and when the receiver is not receiving electromagnetic energy, the biological sensor, processing device and transmitter are inactive.
