Since 1987, the NAL Tokyo has conducted the system definition study and some components tests to investigate the feasibility of 2 types of unmanned aerial vehicles; Microwave-Powered Unmanned Aerial Vehicle (MPUAV) for communication relay utilizations, and Chemical Energy Powered Unmanned Aerial Vehicle (CEPUAV), with very long range capability for the earth observation utilizations. Here MPUAVs which also need chemical energy in climbing phase are described.
The research on energy transmission by microwave has conducted in some universities, CRL (Communications Research Laboratory) and industries, in both transmitting and receiving technologies.
With the extensive use of a simple CAD program for MPUAVs, a configuration of 400kg all up mass and a 30m wing span is proposed, under the tentatively supposed specifications of microwave transmitted DC power supply.
A scenario to develop and verify necessary technologies by scale model flight tests at low altitude is proposed.