Q7.
What
type
of
ships,
in
general,
are
being
upgraded with the Ship Self-Defense System
(SSDS)?
OPTRONICS SYSTEMS
As you have seen, the majority of sensor systems
you will work with are of the RF type. That is, RF
energy is transmitted via a complex system of
components to detect and destroy a target. There are
also other sensors used in todays Navy that use a
different method of locating targets and helping in the
direction of weapons. These systems use light or heat
as a source for target detection. They are described as
Optronic systems because they use light frequency
rather than RF energy as a detecting element and a
system of optical lenses for focusing a light source. An
example of this type of system used in the Navy today
is the Thermal Imaging Sensor System (TISS). It is
representative of other similar optronics systems in use
today.
THERMAL IMAGING SENSOR SYSTEM
(TISS)
The Thermal Imaging Sensor System (TISS) is a
shipboard electro-optical system that consists of a
low-light television camera and an eye-safe laser
rangefinder. The TISS director is designed to be mast
mounted. The control console can be mounted in CIC
or in the pilothouse. In addition to providing surface
and air target data to combat systems, the TISS can also
be used to detect mines and to provide good night
identification and detection capabilities.
TISS was originally tested on board the USS
Ticonderoga (CG-47) and later installed on the USS
Vicksburg (CG-69) for her deployment to the Middle
East in April 1997. TISS will initially be installed as a
stand-alone system on deploying ships. As more units
are completed, permanent installation and integration
into the combat systems will become standard.
Systems that use TISS are the Mk 86 Gun Fire Control
System, CIWS, SSDS, and RAM.
Q8.
What type of system is TISS?
UPCOMING DEVELOPMENTS IN
RADAR
To keep pace with the approaching 21st century
needs for multi-mission surface warships, the Navy is
continually developing new technology that allows it
to do more with less. We mention some of these
developments, related to radar and sensors, below.
HIGH FREQUENCY SURFACE WAVE
RADAR
High frequency surface wave radar is used to
detect low-altitude missiles beyond the ships horizon.
The transmitting antennas are meandering-wave type
units and are mounted on either side of the ship, near
the bridge. The receivers are separate deck-edge or
superstructure units. This radar uses an FMCW
(Frequency Modulated-Continuous Wave) transmitter
with a 50% duty cycle, with co-located transmit and
receive antennas.
MULTI-FUNCTION RADAR
The Multi-Function radar is a development for the
DD-21 Land Attack destroyer that provides ship
self-defense and local area defense against air and
missile threats. The new Multi-Function radar (MFR)
will greatly enhance ship defense capability against
modern air and missile threats in the littoral
environment (areas close to shoreline). This system is
based on solid-state, active-array radar technology that
will provide search, detect, track, and weapon control
functions while dramatically reducing manning and
life-cycle costs associated with the multiple systems
that perform these functions today. The MFR will be
complemented by a new Volume Search Radar (VSR),
which will provide timely cueing to MFR at long
ranges and above the horizon. The VSR will be
acquired as part of the DD-21 total ship system. (See
Figure 2-19)
INFRARED SEARCH AND TRACK (IRST)
The Infrared Search and Track (IRST) system is an
integrated sensor designed to detect and report
low-flying antiship cruise missiles by detecting their
thermal heat plume or heat signature. IRST will
continually scan the horizon and report any contacts to
the ships combat information center for tracking and
engagement. The scanner is designed to search several
degrees above and below the horizon but can be slewed
manually to search for higher flying targets. IRST is a
passive system providing bearing, elevation angle, and
thermal intensity of a target. The system consists of a
mast-mounted and stabilized scanner, below decks
electronics, and a UYQ-70 operators console.
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