By ROBERT KERNO
Capt. Robert Kerno,
USN, is on the Battle Management, Command, Control, Communications, Computers, and
Intelligence (BMC41) staff in the Theater Air Warfare Branch, Surface Warfare Division
(N86) of the office of the chief of naval operations.
Today's air defenses will
be stressed beyond existing capabilities as potential adversaries introduce a variety of
increasingly sophisticated threats over the next decade. Countering these threats, even
with planned new systems, will require an ability to share extremely accurate information
(raw sensor measurement data) in real time between ships, aircraft, and land-based
air-defense units. All sensors and weapons will be used in a common battlespace to the
full extent of their capabilities. The information available to any unit must be precise
and shared throughout the force so that all friendly assets can be used with economy of
force and mass of firepower. Sensor netting, a technique that supports this effort, is
fundamentally different from the current practice of transmitting highly processed track
information between units.
Using sensor netting,
fragmentary contact data available to individual force sensors can be combined
synergistically to form composite tracks. Because each unit is using identical data and
computer algorithms to form its air picture, an identical, interoperable forcewide picture
is formed. The sensor data is shared directly by the radar itself, in real time (0.5
seconds or less), over the Cooperative Engagement Capability (CEC) network. Because the
sensors are netted together, receipt of radar contact information from another unit will
automatically cue all radars in the force to actively look for the new track--all with no
operator intervention required. Each unit's combat systems suite appears as if every other
sensor within the network is its own--in other words, anything detected by one unit is, in
effect, detected by all units, and anything that one unit can see well enough to shoot can
be engaged by every unit within shooting range. Sensor netting will provide for
increased timeliness and accuracy, as well as greatly improved tactical continuity, more
consistent identification, and better engagement decision and prosecution. Moreover,
access to forcewide composite tracks will allow the unit that is in the best position to
do so to intercept enemy aircraft and/or engage cruise and tactical ballistic
missiles--and do so earlier.
The tactical demands of
littoral operations require a Single Integrated Air Picture (SIAP) to achieve theater air
dominance. The SIAP requires complex and highly interoperable combat systems. In essence,
many different combat systems compile data differently, using different computational
algorithms, different computer languages, and different operating systems.
Interoperability is defined as the ability of systems, units, or forces both to provide
services and to accept services from other systems, units, or forces, and to use the
services so exchanged to enable them to operate effectively together.
These conditions are
achieved among communications-electronics systems or items of communications-electronics
equipment when information or services can be exchanged directly and satisfactorily
between them and/or their users. Today, no existing tactical system possesses the
throughput and data-processing capacity required to achieve sensor netting. CEC meets that
requirement by coordinating air-defense sensors and integrating data in such a way that
the network of individual systems forms a dispersed but fully interoperable air-defense
system.
Conceptual
Evolution
The surface Navy
sponsored advanced research and development at the Johns Hopkins University Applied
Physics Laboratory under the Battle Group Anti-Air Warfare Coordination (BGAAWC) program.
This effort, which started in 1975, ultimately became known as the Force Anti-Air Warfare
Coordination Technology (FACT) program, and was charged to investigate ways in which
Battle Group/Force air-defense effectiveness could be improved through the coordination of
ship and aircraft systems. During the past 20 years the program has developed a number of
prototypes that were subsequently procured for Navy-wide use. Among the program's more
conspicuous successes are the Shipboard Gridlock System (SGS), which is vital to today's
data-link operations, and the Detection Data Converter (DDC), an AN/SPS-48 radar
improvement that greatly improves the radar's tracking ability. However, the program's
most significant contribution to the fleet is the CEC concept, which began development in
the mid-1980s.
In 1985, the BGAAWC
program conducted an experiment called Remote Track Launch on Search (RTLOS). The goal of
this experiment was to demonstrate that one ship could engage a target using radar track
information sent over an existing data-link. Although the experiment succeeded, and the
feasibility of the concept was proven, it also became evident that the capacity and
timeliness of "Link-11" was inadequate to handle the magnitude of data required
to transform CEC into a true tactical capability. In 1987, the program embarked on an
effort to develop a link that could accommodate both the required amounts of
information and the data latency necessary to solve the problem. The CEC program was born.
The
Composite Tracking Process
The CEC system consists
of two major new pieces of equipment and a series of modifications to existing systems.
Raw information (individual radar dwell returns) from shipboard sensors and weapon systems
is fed into the Cooperative Engagement Processor (CEP), which reformats the data and sends
it to the Data Distribution System (DDS). The DDS then encrypts and transmits data to
other CEC cooperating units, or CUs. At the same time, the DDS receives data provided by
the CUs and forwards it for use in the CEP. The CEP combines all of the unprocessed
raw-sensor data into an air picture consisting of composite tracks that can be displayed
and used by the sensor and engagement systems of each individual platform.
The DDS uses a narrow
directional signal that: (a) is highly resistant to jamming and hostile intercept; and (b)
allows simultaneous unit-to-unit communications between CUs during each transmit/receive
period. These simultaneous pair-wise communications provide the high data rates and data
timeliness required to conduct cooperative engagements; they also permit instant
reconfiguration of the net as CUs enter and leave.
The CEP, meanwhile,
combines sensor data from all of the CUs to form composite tracks with common track
numbers. Although the picture generated is formed separately on each CU, commonality is
guaranteed because the CEP's identical computer program is applied to the same input data
in every CU. The implication of this is significant: Every cooperating unit takes every
piece of sensor data available in the entire force and, using identical computers,
combines this information to form a picture of the battle space. In other words, every
unit participating sees an identical, accurate depiction of the local tactical
"world" based on sensor data received from all units in the entire force.
In this way, a highly
reliable and consistent composite track, which uses inputs from many sensors--each
operating at different frequencies and illuminating the target from a unique aspect--may
be formed. This capability promises a revolutionary change in the Navy's ability to
coordinate warfare at the tactical level.
Fundamentally
Different But Complementary Links
CEC is fundamentally
different from track-file-based data links, not only in terms of function but also in
terms of the mission for which it was designed. CEC provides for the real-time exchange
between shooters of fire-control-quality data. It was not designed to serve as a joint
command and control network like Link-11 and Link-16, or for the distribution of
non-real-time national-level sensor data such as GCCS (Global Command and Control System).
By design, CEC is complementary to each of these systems, each of which is designed to
perform unique, essential functions. Each carries a different kind of information, with
differing requirements regarding timeliness and precision.
CEC
Warfighting Benefits
CEC dramatically enhances
the ability of the entire force to detect, track, and engage even the most difficult
targets. Every unit has real-time access to the sensor data received from every other
unit, and each unit is able to conduct engagements as if all of the sensors in the force
had been "slaved" for the exclusive use of that unit. This capability:
- Extends force detection
ranges through remote cueing. Once a unit has sensed a target that exceeds its own
sensor threshold its report on the target, however fragmentary, will automatically cue
other radars in the CEC network to "look" for the same track.
- Provides a quantum
improvement in track and ID continuity. With CEC, a composite track is formed using
multiple radars, each looking at the target from a different perspective, and at different
frequencies. Consequently, CEC enhances the quality of a track in its network because of
its inherently additive ability to use every available scrap of data to create a more
reliable composite track.
- Provides tracking
accuracy superior to that possible from any single sensor. Because multiple
unit/sensor inputs form the CEC picture, it applies multiple look angles and different
frequencies to solve the problem. This results in a much quicker and more accurate
smoothing of available data into a composite track.
- Expands the capability
of existing sensors and weapons. The entire force can now use tracks detected by any
force sensor. Missiles can now engage tracks never actually detected by the firing
platform's organic sensors.
- Significantly increases
depth of fire. Because CEC remote track data is of fire-control quality, a
CEC-equipped ship, formerly limited by its own radar horizon, can launch on remote track
data to permit missile intercept of a low-flying threat just as the threat crosses the
radar horizon--permitting, in the event that the engagement is unsuccessful, a second
opportunity for engagement.
- Permits engagement of
targets not held by own ship sensors. Even if a ship's primary air-search radar is
being jammed, suffering interference, experiencing adverse atmospherics, or otherwise
unable to detect the threat, the ship can still engage--by using the composite data
received from other ships.
- Enables self-defense
systems to maximize performance against stressing targets. The self-defense system's
missile is able to take advantage of the composite data provided by the more accurate and
more powerful sensors in the CEC network to permit engagements not possible without CEC.
Joint
Interest in CEC
Both the Army and the Air
Force are examining potential CEC applications for their existing and planned forces. CEC
integration with Patriot, the Army's missile-intercept system, for example, is a
substantial joint-warfare capability multiplier. It is generally accepted that a major
improvement in theater ballistic missile defense (TBMD) capability would accrue through
the netting of the Navy's Aegis SPY radar with the Patriot MPQ-53 radar. Netting the Aegis
S-band SPY radar with the X-band Ground-Based Radar (GBR) of the Army's THAAD (Theater
High-Altitude Air-Defense) system also holds promise for dramatically improving
discrimination of TBM (theater ballistic missile) targets from other nearby objects
outside of the atmosphere.
CEC integration into
AWACS (Airborne Warning and Control System) could have just as significant joint
warfighting implications; the Air Force is for that reason investigating installation of a
Common Equipment Set (CES) on an AWACS aircraft for initial testing and evaluation. The
Air Force also is installing a prototype Infrared Search and Track (IRST) system, known as
"Eagle," on an AWACS platform. Conceivably, the integration of IRST into the CEC
network could yield major dividends by enabling an airborne IR sensor to accurately cue
land- and sea-based radars in real time.
Conclusion
CEC is a unique system
that has the potential of providing a revolutionary change in the force's ability to
accurately portray the battlefield and engage the threat. The abilities of the CEC network
are significant, and allow for the development of an identical common air picture,
increased force detection ranges, more consistent tracks, and enhanced interoperability.
Most importantly, the unit in the best position to engage will be able, whether or not its
own sensors hold the target track, to draw on all force data in order to consummate the
engagement. The potential applications of CEC in the joint arena are extensive: Patriot;
AWACS; USMC TPS-59 (V) 3 radar; THAAD/GBR; E-2C Hawkeye, and Aegis--in the future, all may
be linked in real time to keep U.S. joint air-defense forces well ahead of the threat. |
