Passive Wireless Microsystems

Abstract

Passive wireless microsystems such as wireless transponders, radio-frequency identification (RFID) tags, wireless microsensors, and biomedical implants, harvest their operational power either from radiofrequency waves emitted by their base station or from other energy sources such as vibration and solar. The absence of bulky batteries not only minimizes the physical dimension and implementation cost of these microsystems, it also removes the need for maintenance. As a result, passive wireless microsystems can be embedded in products or implanted in living bodies permanently to provide the unique identification of the products or living bodies in which they reside, to provide the precision measurement of the parameters of the products or living bodies, and to carry out control actions in a micron scale that otherwise cannot be performed. The key intrinsic attributes of passive wireless microsystems include small size, battery-less and maintenancefree operation, programmability, and wireless accessibility.