Y. Konishi et al., BEAM SCANNING CHARACTERISTICS OF AN OPTICALLY CONTROLLED ARRAY ANTENNA FED BY A FIBER OPTIC ARRAY, Electronics & communications in Japan. Part 1, Communications, 79(2), 1996, pp. 35-45
For an optically controlled array antenna in which the microwave excit
ation distribution is generated and controlled in the optical domain b
y means of the optical Fourier transform and the optical/electrical (O
/E) conversion, element antenna excitation, and the radiation characte
ristics are theoretically and experimentally studied in the case in wh
ich the image mask is shifted from the optical axis of the Fourier tra
nsforming lens for an intended beam scanning. A planar fiber optic arr
ay was constructed and the excitation profile and the radiation patter
n were experimentally investigated by means of a fiber optic array. Fi
rst, the excitation profile and the beam scan angle were theoretically
expressed in the case in which the circular aperture image mask shift
and beam scan angle is derived. From the excitation profile experimen
t using a type of two-laser optically controlled array system, it is s
hown that the excitation profile necessary for the beam scanning can b
e obtained. From the calculation of the radiation pattern, the beam sc
anning corresponding to the computed value is possible. A 61-element f
iber optic array was then designed for trial. By using the excitation
profile experiment with this array, it is shown that the excitation pr
ofile and the beam scanning characteristics can be obtained with the f
iber optic array if the transmission loss of the fiber optic array is
compensated for.