Directional antennas: a directional radiation pattern can
be viewed as analogous to speaking with a particular
person: your (the antenna’s) aim is to speak only to
(transmit signals to) the other person, and to hear only
from (receive signals from) the other person.
Omnidirectional antennas: an omnidirectional radiation
pattern can be viewed as analogous to speaking to a room
of people: your (the antenna’s) aim is to speak to
everyone in the room, and to hear from (receive signals
from) everyone in the room
Antenna
arrays: typically a composite of multiple
directional antenna elements in a single unit, with
different elements pointing in different directions,
can include an integral omnidirectional antenna
element. Arrays are often used for direction-finding
or electronic attack.
Antenna
Performance Feature Examples:
Constant
aperture: Our antenna will receive the same signal
strength from an antenna transmitting constant power at
any frequency. If the sender transmits at the same power,
regardless of frequency, our antenna will receive the same
signal strength. This means that if the sender changes
their frequency, we do not lose the signal.
Increasing gain with frequency: Enables constant effective
aperture (see above)
Time
non-dispersive: True ultrawideband, can receive any
signal in the frequency range, i.e. it will not
distort/spread impulse-type (ultrawideband) signals on
receive or transmit
Antenna
and Antenna Array Application Examples:
Direction-Finding (DF): Determining the direction that an
unidentified (potentially adversary) signal is coming
from.
Electronic Attack (EA): This usually means “jamming” an
adversary signal (in the speech analogy, this can be
compared to shouting when someone is speaking, so that the
listener cannot hear their message)
Information Operations (IO): A broad category of DoD
signal activities including direction-finding and
electronic-attack. Other terms that have been broadly used
include information warfare and electronic warfare, but
“information operations” is closer to being an “all
encompassing” term.
