%0 Journal Article %A Likhograi, V. G. %D 1997 %I Begell House %N 4 %P 46-52 %R 10.1615/TelecomRadEng.v51.i4.70 %T Optimizing Power Transmission by a Microwave Beam in the Presence of Random Errors of the Transmit Antenna Excitation %U https://www.dl.begellhouse.com/journals/0632a9d54950b268,33c8731363039cb6,6e66597d10e269fd.html %V 51 %X An important part of a space borne power system is its microwave power transmission line consisting of a transmit antenna, the propagation space and a receive rectenna [1-3]. The rectenna is an array of radiating elements whose outputs are connected to rectifiers. The d. c. power is collected in a common load using a linear collecting circuit combining parallel and series connections.
In terms of energy, the performance of the transmission channel can be estimated through its efficiency, which depends on sizes of the transmit and receive antenna apertures, spacing between the antennas, their mutual orientation, distribution of the excitation field across the transmitting aperture and parameters of the rectifying elements.
The effect of these factors on the power transmission has been investigated quite completely. As has been found efficient power transmission is achieved if the rectenna is located in the Fresnel zone of the transmitting antenna, the amplitude distribution across its aperture is close to a truncated Gauss distribution, and the phase distribution approaches a square law with the phase front radius of the curvature equal to the distance between the antennas [4,5]. The effects of amplitude, phase and polarization fluctuations in the beam cross-section have also been investigated [6]. A method has been suggested for synthesizing the amplitude distribution of a focused transmitting antenna to provide a maximum efficiency of power transmission with account of efficiencies of the receiving-rectifying elements [7].
For a number of manufacturing and operational reasons there are some other factors, which can affect significantly the efficiency of power transmission, namely, the amplitude and phase fluctuations of the field across the transmitting aperture. This paper is devoted to the transmission line optimization according to the criterion of maximum average efficiency. The excitation field distribution of the transmit antenna is determined which should provide a maximum of the average efficiency with given parameters of the amplitude and phase fluctuations. %8 1997-04-01