Microwave and millimeter-wave rectifying circuit arrays and ultra-wideband antennas for wireless power transmission and communications

摘要

In the future, space solar power transmission and wireless power transmission willplay an important role in gathering clean and infinite energy from space. The rectenna,i.e., a rectifying circuit combined with an antenna, is one of the most importantcomponents in the wireless power transmission system. To obtain high power and highoutput voltage, the use of a large rectenna array is necessary.Many novel rectennas and rectenna arrays for microwave and millimeter-wavewireless power transmission have been developed. Unlike the traditional rectifyingcircuit using a single diode, dual diodes are used to double the DC output voltage withthe same circuit layout dimensions. The rectenna components are then combined to formrectenna arrays using different interconnections. The rectennas and the arrays areanalyzed by using a linear circuit model. Furthermore, to precisely align the mainbeamsof the transmitter and the receiver, a retrodirective array is developed to maintain highefficiency. The retrodirective array is able to track the incident wave and resend thesignal to where it came from without any prior known information of the source location. The ultra-wideband radio has become one of the most important communicationsystems because of demand for high data-rate transmission. Hence, ultra-widebandantennas have received much attention in mobile wireless communications. Planarmonopole ultra-wideband antennas for UHF, microwave, and millimeter-wave bands aredeveloped, with many advantages such as simple structure, low cost, light weight, andease of fabrication. Due to the planar structures, the ultra-wideband antennas can beeasily integrated with other circuits. On the other hand, with an ultra-wide bandwidth,source power can be transmitted at different frequencies dependent on power availability.Furthermore, the ultra-wideband antenna can potentially handle wireless powertransmission and data communications simultaneously. The technologies developed canalso be applied to dual-frequency or the multi-frequency antennas.In this dissertation, many new rectenna arrays, retrodirective rectenna arrays, andultra-wideband antennas are presented for microwave and millimeter-wave applications.The technologies are not only very useful for wireless power transmission andcommunication systems, but also they could have many applications in future radar,surveillance, and remote sensing systems.