  The purpose of the following proposal is to create a new class of antennas of
low weight but with a large transmitting and receiving surface made of
metallized fabric. This class of antennas will be stationed in low satellite
orbits, at about 2000 km from sea level and will be easily steerable by
exploiting the interaction between the earth's magnetic field and an
electromagnetic field generated on the antenna. The possibility of orienting
very large ultra-light balloon-like MW antennas, orbiting in the Earth magnetic
field, through electric currents flowing in conductive wires embedded in the
antennas walls, are examined. It is shown that such currents may easily provide
the needed forces without the necessity of mechanically orienting the antenna
itself. The antenna is extremely light, inexpensive, easily directional. The
antenna has the shape of a spheroid in which the southern hemisphere has a
parabolic shape made of metallized fabric; the northern hemisphere, transparent
to the electromagnetic radiation, has a radius of curvature such that the north
pole coincides with the focus of the parabola.
