AN/SPY-1
The AN/SPY-l radar system is the primary air and
surface radar for the
Aegis Combat System installed in
the Ticonderoga (CG-47) and
Arleigh
Burke (DDG-51)-class warships. It is a multi-function phased-array radar
capable of search, automatic detection, transition to track, tracking of air and
surface targets, and missile engagement support.
A conventional, mechanically-rotating radar
"sees" a target when the radar beam strikes that target once during
each 360 degree rotation of the antenna. A separate tracking radar is then
required to engage each target. By contrast, the computer-controlled AN/SPY-1A
Phased Array Radar of the AEGIS system brings these functions together within
one system. The four fixed arrays of "SPY" send out beams of
electromagnetic energy in all directions simultaneously, continuously providing
a search and tracking capability for hundreds of target at the same time.
STRENGTHS
- ANSPY-1 multifunction, phased array, fire
control quality radar.
- Very rapid transition from SPY-1 silent to
full radiate and full situational awareness.
- Fast reaction, fully/semiautomatic combat
systems. Initial detection to first missile movement in less than 10 sec.
- Salvo rate of less than 2 sec per launcher
(CG-52 and above with MK 41 VLS)
- Mix of multiple SMs.
- Max field of fire and min blockage zones
- Must illuminate target only for a short
duration prior to intercept.
- AN/SPY-1 radar variable sensitivity feature
allowing radar sensitivity to be tailored to threat Radar Cross Section (RCS),
environment, and tactical situation.
- Weapons & ID doctrine capable of automatic
and semiautomatic response/action.
- Doctrine software assists w/ ID
WEAKNESSES
- The system is designed for blue water and
littoral operations however AN/SPY-1 configuration must be modified to look
above the terrain to avoid causing excessive false targets from land
clutter. These configuration changes may increase ship susceptibility to low
and fast targets.
- Once a target is engaged and the initial salvo
fired, WCS will not allow the target to be reengaged (second salvo) until a
kill evaluation has been completed.
- AN/SPY-1 antenna height is lower than the
AN/SPS-49 radar system resulting in reduced radar horizon.
- DDG-51 Class are not equipped with a AN/SPS-49
radar (no secondary air search radar)
- Must hold an AN/SPY-1 track. Cannot engage on
a remote or AN/SPS-49 track unless equipped with CEC.
The SPY-1 radar program began in the early 1970s as
part of the AEGIS weapon system development and acquisition process. Three
versions of the radar have been delivered.
- The first radar of the SPY-1 series, SPY-1A,
is installed in the First AEGIS Cruiser, USS TICONDEROGA (CG 47), and
subsequent ships until USS PHILIPPINE SEA (CG 58).
- As technology improved, the development
program fielded a new version of SPY-1. This new radar is the SPY-1B
and, with its upgrade the SPY-1B(V), was built into USS PRINCETON (CG-59)
and the remaining AEGIS cruisers. CG-59 through CG-73 are equipped with the
the SPY-1B.
- USS ARLEIGH BURKE (DDG 51) class ships, AEGIS
destroyers, received the SPY-1D, the latest generation of the SPY-1
family. SPY-1D is a variant of the SPY-1B radar system on later TICONDEROGA
(CG-47) class cruisers, tailored for a destroyer-sized ship.
The SPY-1D(V) radar upgrade is the newest
improvement to the SPY-1D. The SPY-lD( V) littoral radar upgrade will supersede
the SPY-1D in new-construction ships beginning in FY 1998, and will deploy in
DDG 51 Flight IIA ships starting in approximately 2003. The third variant of
this radar, known as the Littoral Warfare Radar, will improve the radar's
capability against low-altitude, reduced radar cross-section targets in heavy
clutter environments and in the presence of intense electronic countermeasures.
The SPY-1D radar system is the multi-function, phased-array, three-dimensional
(range, altitude, and bearing) radar which conducts search, automatic detection,
and tracking of air and surface targets. The SPY-1D also provides mid-course
guidance for the SM-2 missile, and has also demonstrated a capability to track
theater ballistic missiles. The AN/SPY-1D(V), under development for installation
in some Flight IIA ships, is an improved system with better performance against
targets in clutter, additional moving target indicator (MTI) waveforms, and
greater ability to counter deceptive Electronic Attack measures.
In May 1996, the Commander, Operational Test and
Evaluation Force conducted the initial operational test of the SPY-1D(V) radar
upgrade at the Moorestown site. The challenge of testing a naval radar in a
ground environment was enormous. The Site lacked dynamic sea clutter, oceanic
atmospheric anomalies, and very low flying targets. These limitations of the
land-based Site were overcome by the extensive use of models and simulations.
These models and simulations replicated the at-sea operating environment,
providing simulated sea clutter, atmospherics, targets, and electronic jamming.
All the models and simulations were accredited for use in this test after
surviving a rigorous validation procedure to determine their suitability. After
a successful operational test, the SPY-1D(V) was approved for limited rate
inital production by the Assistant Secretary of the Navy (Research, Development,
and Acquisition) in December 1996.
Current funding completes the development of an
upgrade to the current AN/SPY-1D radar, Engineering Development Model 4B
(EDM-4B), to enhance its capability against low cross section sea skimming
targets in increasingly more severe electronic countermeasures and in near-land
clutter environments. The changes are in the transmitter, signal processor, and
radar control computer program. for the ARLEIGH BURKE (DDG 51) class ships Two
new efforts will start in FY 1999. First, support for a Ballistic Missile
Defense Organization (BMDO) Program which is developing a common, backfittable
theater-wide radar upgrade signal processor to provide affordable theater-wide
exoatmospheric discrimination capability. Second, integration of the AN/SPQ-9B
radar into the AEGIS Weapon System to improve capability against the advanced
low-altitude threat.
Expanded common signal processor design for the
AN/SPY-1 Radar includes advanced AAW functionality and features. The expanded
signal processor design will add AAW functionality to and leverage the common
signal processor’s TBMD functionality design currently being pursued via TBMD
funding. The advanced AAW functionality will implement adaptive digital signal
processing to improve low altitude clutter rejection performance and ECCM
capabilities.
The installation and integration of the AN/SPQ-9B
Radar (or its advanced variant) in the AEGIS Weapon System will include
remaining modification work for backfit in destroyers and cruisers.
Sources : fas.org (Federation of American Scientists)