University of Tokyo School of Engineering
University of Tokyo School of Engineering
University of Tokyo Graduate School of Frontier Sciences
University of Tokyo Graduate School of Frontier Sciences
University of Tokyo School of Engineering
出版者
宇宙航空研究開発機構宇宙科学研究本部
出版者(英)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA/ISAS)
雑誌名
第24回宇宙エネルギーシンポジウム 平成16年度
雑誌名(英)
The Twenty-fourth Space Energy Symposium March 7, 2005
ページ
105 - 109
発行年
2005-06
抄録(英)
'Innovative Aerial Robot Project' (IARP) is a project for Unmanned Aerial Vehicle (UAV) and Micro Aerial Vehicle (MAV) which is carried out as part of the 21st century COE program 'Mechanical Systems Innovation'. 'Innovative' means that MAV contains some challenging technologies. In this project, we plan to transmit microwave energy for MAV by phased array antenna. The microwave phased array technology has been intensively developed for energy transmission in space, such as the transmission from a Space Solar Power Station to the ground. This technology will be applied in this project. Namely, pointing of the microwave beams will be achieved by controlling the phase of element microwaves, not by mechanical control of the antennas' attitude. MAV will fly in circles and the phased array antenna should continue to transmit microwave energy for flying MAV. Then the tracking of the flying object would be challenging. Retro-directive function will help its quick and precise tracking. This paper describes the current status of system development for the microwave phased array. In the final stage of the project, IARP, the flight demonstration will be inevitable. In this experiment, we have constructed microwave phased array system. The microwave is provided by a 5.8 GHz Field Effect Transistor (FET) microwave oscillator (Almotech Co,) and divided into three elements using a power divider. The phases of the microwave elements are controlled individually using two 6-bit phase shifters, whose phase resolution is 5.6 deg. The phase shifters are controlled by a PC digitally. Three FET amplifiers with the output power of 1 watt each are used to have totally 3 watts output power. Each microwave is guided to each antenna. In this experiment, horn antenna is used in order to cut down the number of antenna. The power profile will be measured using a patch antenna set on a traverse stage. In order to eliminate the microwave power reflected on walls of the experimental room, the walls are covered by absorbers containing plenty. For some patterns of three phases of the microwave elements, the spatial power profile will be measured using the system and compared with the numerical simulation that drives from Maxwell equations. Although the antenna array is arranged in one dimension in this experiment, the power profile from antenna array with arrangement of two dimensions are estimated from this numerical simulation easily.