Genesis' telecommunications subsystem is composed of both
a radio system operating in the S-band microwave frequency
range and a system that operates in the ultra high frequency
(UHF) range. The S-band system provides communication
capability between Earth and the spacecraft throughout
all phases of the mission. The UHF system is located in
the sample return capsule; after parafoil deployment,
it provides a backup tracking capability.
The spacecraft's radio system communicates with Earth
though a medium-gain antenna. The medium-gain antenna
is spiral-shaped, about 10 centimeters (4 inches) in
diameter, about 12 centimeters (4.87 inches) tall and
weighs 105 grams (about 4 ounces). The spacecraft also
houses four low-gain antennas, located on the underside
of the craft. These are patch antennas, which sit on
a coaster-size square (10 by 10 by 1 centimeters (4
by 4 by 0.4 inches)). These have a much wider field
of view.
The low-gain antennas will be used to make initial
contact with the spacecraft after it leaves Earth's
atmosphere, and afterwards only for emergencies. The
medium-gain antenna will be used for most of the spacecraft's
communication with Earth.
The telecommunication subsystem weighs 10.1 kilograms
(22.3 pounds). |
