Research on Active Transmitting and Receiving Antennas in Microwave Energy Transmission Systems

我们的研究项目的目的是开发空间太阳能卫星系统中接收或发射微波功率的有源天线系统。以下结果是基于前一项研究项目获得的专利。首先，为了设计2.45 GHz频段的天线元件和微波电路，提出了“虚拟实验环境”的概念。微波电路由发射有源天线系统组成，该系统采用相位控制算法进行波束控制。天线单元采用背腔式缝隙天线。其次，为了从理论上对天线单元进行设计，提出了将时域有限差分技术应用于天线单元的设计。数值计算结果与实验结果吻合较好，验证了该方法的有效性。此外，还开发了具有简化馈电结构的新型天线单元。在“虚拟实验环境”中，为有源天线系统设计了采用硅半导体器件的微波电路。最后，设计了一种新的缝隙耦合圆形微带天线(CMSA)，它是传统缝隙耦合圆形微带天线的改进形式。此外，还提出了一种新的狭缝设计，以抑制在2.45CHz的较高奇次谐波频率下来自匹配部分的二次辐射。该设计在数值和实验上都得到了验证。

The purpose of our research project is to develop active antenna systems for receiving or transmitting microwave power in space solar power satellite systems. The following results are based on the patent obtained from the previous research project. First, the concept of "the virtual experiment environment" is proposed in order to design the antenna elements and the microwave circuits at the frequency of 2.45GHz. The microwave circuits are composed the transmitting active antenna system which uses the phase-control algorithm for beam steering. The cavity-backed slot antenna is proposed as the antenna element. Second, the application of the finite-difference time-domain technique is proposed in order to design the antenna element theoretically. The procedure is verified since numerical results agree with experimental ones. Furthermore, new antenna elements with simplified feeding structure are developed. In "the virtual experiment environment", the microwave circuits using silicon semiconductor devices are designed for the active antenna system. Finally, a new slot-coupled circular microstrip antenan (CMSA) is designed, which is a modified form of conventional CMSA with the slit cutting. Moreover, a new design for the slits is proposed to suppress re-radiation from the matching section at higher odd harmonic frequencies of 2.45CHz. The design is verified both numerically and experimentally.