Millimeter Wave Power Transfer to an Autonomously Controlled Micro Aerial Vehicle

The present paper is the first report of an experimental study on the energy efficiencies in the millimeter wave power transfer to an autonomously-controlled micro aerial vehicle (MAV). A tight beam of millimeter wave at 28 GHz was transmitted vertically upward, and a quad-rotor type MAV was autonomously controlled using the iterative feedback tuning method to hover over the beam and receive the millimeter wave power. The maximum value of the receiver efficiency was (1 +/- 2) x 10(-3) and its duty ratio was 0.29 +/- 0.08, for which the distance between the MAV and the millimeter wave transmitter was 800 mm. The energy loss and the low duty ratio were both due mostly to the loss in the capture efficiency due to the location scattering of the MAV.