Simultaneous wireless power transmission and data communication.

摘要

The rapid development of low power wireless electronic systems has led to countless research activities in connection with the feasibility of a remote or wireless powering of those systems. Therefore, wireless power transmission (WPT) has become a focal point of interest since many years, which is being developed as a promising technique, for powering electronic devices over distance and for enabling the design and development of self-powered systems. The rectifying antennas known as rectennas are the most important elements in long-range wireless power transmission. The efficiency of rectennas mainly depends on their antennas and the related rectifier circuits. Therefore, to design a high-efficiency rectenna that guarantees the quality of a WPT system, more focus should be concentrated on the investigation, analysis and development of high-gain antennas and performance-driven rectifiers with reference to high RF-to-DC conversion efficiency. In the literature, different configurations of rectenna circuit, mainly operating at low frequency such as 2.45 GHz and 5.8 GHz, have been widely investigated. However, there are just a few reported studies at millimeter-wave frequency although the advantages of more compact size and higher overall system efficiency for long distance transmission can be obtained at millimeter-wave frequency.;On the other hand, rectenna circuits can just scavenge energy and they cannot decode the transmitted signal for communication purpose. However, the data transmission is an essential requirement of wireless communication systems. Therefore, if the ability of signal detection and processing can be added to a rectenna architecture then a receiver with simultaneous wireless power transmission and data communication can be realized. The realization of such a system can be considered as a promising approach for the next generation of self-powered communication systems.;This PhD dissertation aims to investigate and demonstrate a system of wireless power transmission and also a receiver with the capability of simultaneous wireless energy harvesting and data communication operating at up-microwave and millimeter-wave frequency. To achieve these goals, different structures of rectifier circuit are studied, designed and experimentally measured. Also various antennas are investigated and the required factors for a WPT antenna are specified. Moreover, this study addresses design and implementation issues of a 24 GHz rectenna, which is developed to demonstrate the feasibility of wireless power harvesting and transmission techniques towards millimeter-wave regime. The proposed structure includes a compact circularly polarized substrate integrated waveguide (SIW) cavity-backed antenna array integrated with a self-biased rectifier using commercial Schottky diodes. The antenna and the rectifier are individually designed, optimized, fabricated and measured. Then they are integrated into one circuit in order to validate the studied rectenna architecture. The maximum measured conversion efficiency and DC voltage are respectively equal to 24% and 0.6 V for an input power density of 10 mW/cm2. To the best of our knowledge, the measured efficiency is the maximum reported to date at this level of input RF power and the operation frequency.;Furthermore, several architectures of wireless receiver are studied to design and demonstrate a receiver for simultaneous wireless power transmission and data communication. Considering the underlying desirable features for developing wireless receivers such as low-power consumption, simple structure, compact-sized and low-cost structures, the multiport (six-port) interferometer receivers are selected as a proper approach to design such a receiver. To do so, various structures of a six-port junction are investigated and an appropriate configuration of microstrip six-port junction operating at 24 GHz is designed and prototyped using our in-house miniaturized hybrid microwave integrated circuit (MHMIC) technique. In continue a special high efficiency detector module with ability of dividing DC voltage with a specific ratio is designed and connected to the six-port junction to realize the six-port receiver. Finally, the ADS simulation of the six-port receiver with feature of power harvesting and data detection is presented and its performance in terms of constellation points and BER are compared to the conventional counterpart.