摘要: | 研究期間:10205~10304;Wireless communication utilizes electromagnetic waves to carry information. As the electromagnetic waves propagate through the space, information can be sent to distant locations without physical wires. Today, wireless data transmission technology has become an indispensible part of our daily life and has greatly improved the user experience of electronic devices. Although wireless communication technology has eliminated the need for wires in data transmission, the delivery of electricity for powering electronic devices still requires physical wires. Unless wireless power transmission technology is introduced, wireless devices cannot be truly wireless. The development of wireless power transmission technology would reduce the dependence of electronic devices on batteries, minimize the size and weight of required batteries, lower the frequency of battery replacements, and further enhance the mobility/portability of next-generation electronic devices. Wireless powering technology utilizes the energy carried by electromagnetic waves to supply the electricity needed by electronic devices. Generally speaking, current technologies for wireless electricity can be divided into three classes, namely, EM radiation, resonant coupling, and inductive coupling. Among them, EM radiation is a far-field technology whereas the other two are near-field technologies. Wireless power through EM radiation are especially suitable for applications such as wireless sensor network, which requires little power but demands long transmission distance beyond the reach of near-field technologies. Using EM radiation technology for wireless powering of wireless sensor nodes is the aim of this project. This project is subproject seven of the joint project “Green Sensor Network towards Intelligent Life and Care Applications.” The goal of this project is to develop wireless power transmission technology for smart sensor nodes, which would help reduce the capacity requirement of the battery in the node, and make the node lighter, more portable, and easier to maintain. We will use 2.45-GHz ISM band for wireless power transmission. The target transmission distance is 3 m, which is the distance from the ceiling to the floor of a typical room. The maximum received power at sensor node (3 m away from the transmitter) is 10 mW. What can be done include frequently charging of the rechargeable batteries in wireless sensor nodes and directly supplying the power needed by low-power sensors. We plan to design and fabricate the T/R modules for a wireless power transmission system. The transmitter module adopts phased array architecture so as to concentrate the power in the direction of a specific sensor node for charging its battery wirelessly while refraining from interfering with the communication links of other devices. The receiver module is made of an antenna and a rectifier, by which the RF power is converted to DC power. The period of this project is three year. In the first year, we will design and measure the integrated circuits required for the wireless power T/R modules, and also develop the design automation process in collaboration with subproject five. In the second year, we will fabricate and test the phased-array transmitter module, and, along with the power management unit developed by subproject six, experimentally verify wireless power transmission. In the third year, we will integrate our modules with the DSP and control units developed by subproject two and three for the realization of smart wireless power management. |