The University of Tokyo, NEC Corp, NEC Engineering Ltd, CellCross Co and the research group from Teijin Limited have developed new technologies, with support from the National Institute of Information and Communications Technology, that provide electronic devices with wireless LAN communications and a power supply through a single sheet of material.
These technologies enable electronic devices with specialized couplers to access wireless communications and power supplies by capturing electromagnetic waves in the vicinity of a transmission sheet. These electronic devices access high speed communications using electromagnetic waves from microwave bands, as well as power supplies with a transmission efficiency of more than 25%.
Communications and power supplies from existing transmission sheets and couplers suffer from high leakage of electromagnetic waves as well as poor efficiency in power transmission.
Recent changes in the structure of both sheets and couplers, however, resulted in new electromagnetic wave control technologies that further suppress the leakage of electromagnetic waves. Moreover, new highly efficient transmission technologies also improve the efficiency of transmissions.
Tests of these new technologies with a prototype transmission sheet that is 60cm on all sides demonstrated high speed communications through a 5GHz wireless LAN and provided a power supply with transmission efficiency of more than 25% at more than 4W on a 2.4GHz band. Furthermore, the safety and possible commercialization of these technologies were also demonstrated by their low levels of electromagnetic wave emissions, well within protection guidelines, when near or directly handling the equipment.© Japan Today