A high-efficiency magnetically coupled charging and communication platform for microsensors

A miniaturized double layered antenna (0.74 by 0.74 mm) was fabricated and integrated with a commercialized passive RFID chip [1] to form a microsensor to work with a highly efficient magnetically coupled reader antenna for wireless charging and communication. Two techniques were developed to boost the magnetic field strength more than 100 times passively without increasing input power. A magnetically coupled antenna array was also employed, expanding the magnetic field coverage to 4 times of the original covered area. Thanks to the techniques mentioned above, we experimentally demonstrated wireless charging and communication with microsensors in a 4-inch distance, with only 0.5 W power input.