Weapon Locating Radar
Encyclopedia
The BEL Weapon Locating Radar (WLR) is a mobile artillery
locating Phased array radar developed by India
. This counter-battery radar
is designed to detect and track incoming artillery and rocket fire to determine the point of origin for Counter-battery fire
.
The WLR has been jointly developed by DRDO's Bangalore
based laboratory, LRDE
and the Government
owned Bharat Electronics Limited
(BEL). The sub-systems have been fabricated by BEL based on the DRDO designs and delivered to LRDE for integration.
. In February 1995, a Request for Proposal
(RFP) was issued to five companies for procurement of 4 WLRs. Only Hughes (now Raytheon
) responded to the RFP. After trials, the radar was found to not be meeting the General Staff Quality Requirements (GSQRs) of the Indian Army, which were found to be too stringent, and were relaxed. At the same time, it was decided to consider development of an indigenous WLR by India's primary defense contractor, DRDO.
In September 1998, an RFP was issued for the urgent purchase of WLRs - An/TPQ-36/37 from Hughes (USA), Thomson CSF (France
) and ISKARA of (Ukraine
). However, the American and French radars were withheld after sanctions were imposed after the Pokhran-II
Nuclear tests, and negotiations with the Ukrainian manufacturers came to no conclusion. Additionally, DRDO was not authorized to begin development of a WLR. These lacklustre efforts to obtain a WLR system were severely criticized by the Parliamentary Standing Committee on Defence.
Efforts to acquire such a system intensified after the Kargil War
, where the Indian Army was severely disadvantaged by its lack of firefinding radars. While the Pakistani forces were equipped with American AN/TPQ-36 Firefinder radar
s, India only had British Cymbeline mortar detecting radars, which were not suitable. Almost 80% of Indian casualties during the war resulted from enemy artillery fire, making such a radar critical.
To correct this weakness, in 2002, the Ministry of Defence issued an RFP to five manufacturers. With the lifting of sanctions in late-2001, the US Government offered to sell the AN/TPQ-37 radar to India under their Foreign Military Sales (FMS) programme for . 68 Crores each. In July 2002, India placed a $200 million USD order for 12 AN/TPQ-37 Firefinder radar
s. Initially, only 8 were ordered for $140 million USD, but the order was later increased to 12. The radars were integrated on BEML
-manufactured Tatra truck platforms. Delivery of all 12 radars was completed in May 2007. Concept design work on the WLR also accelerated in the aftermath of the Kargil War
.
The WLR project was officially sanctioned in April 2002, with a sanctioned amount of . 20 Crores and an estimated completion time of 40 months. The first working prototype was to be ready by April 2004. The final project cost was $49 million USD. In January 2003, an intent for procurement of 28 WLRs was placed with BEL.
in design and performance but is reportedly more user friendly. It is a passive phased array
radar, derived from the Rajendra Radar
(which is the fire control radar for the Akash missile
system). During tests of the Akash missile
at Chandipur, engineers noticed the Rajendra radar was able to detect and track artillery
shells being test fired at a nearby range. Based on this observation, LRDE scientists were able to adapt the Rajendra Array into the WLR.
The WLR Array is an electronically-steered radar, meaning the radar antenna does not move while in operation. The radar can electronically scan a +/-45º range of azimuths for incoming rocket, artillery and mortar fire. The radar antenna is slewable up to +/-135º within 30 seconds, which gives the WLR the ability to quickly change its scanning sector, and provides it 360o scan capability. The Coherent TWT based transmitter of the WLR emits 40 kW of power.
Tracking of the target is done with monopulse signals with Pulse compression
, which improves the radar's LPI
. The radar processors conduct real time signal processing of the received signals. The weapon locating algorithm is an adaptive algorithm based on a modified version of the Runge-Kutta method, and uses Constant false alarm rate
(CFAR) techniques to detect the target accurately. The operator can choose the CFAR technique to be used to maximize the accuracy of information. The data is processed on a programmable digital signal processor
using a modified extended Kalman filter
, with two filters - one with 6 states, and another with 7 states. Clutter rejection is achieved through Moving target indication
(MTI), Airborne MTI (AMTI) and Fast Fourier Transform
(FFT).
Information is displayed on ruggedised
power PCs on a high resolution multi-mode colour display. The data is displayed in real-time and can be overlayed on a 3D digital map. The WLR can store a 100 km x 100 km size digital map for display at any time. Other modes include Plan position indicator
(PPI) display, RHI displays, etc. Up to 99 weapon locations can be stored and tracked at any time and can be transmitted to the command centre.
The detection range for large caliber artillery rounds is up to 30 km, and increases to 40 km for unguided rockets. The robust design of the radar array and algorithms allows the WLR to effectively operate even in a high density fire environment, in severe clutter and interference (jamming) conditions. Up to 7 targets can be tracked simultaneously. The radar can track rounds fired at both low and high angles, and at all aspect angles - from behind or towards the radar, or at an oblique angle to the array. The WLR features adaptive radar resource scheduling to increase efficiency and reliability.
At a given position, the radar can scan for targets in one quadrant, encompassing a 90o sector. The array can electronically scan up to +/-45o from its mean bearing. Additionally, for 360o coverage from a given position, the whole array can be rotated by 135o on either side within 30 seconds to quickly change the scanning sector in response to threats.
Upon detecting an incoming round, the automatically acquires and classifies the threat and initiates a track sequence, while continuing to search for new targets. The incoming round's trajectory is tracked, and a computer program analyzes the track data and then extrapolates the round's point of origin. This calculated point of origin is then reported to the radar operator, thus allowing friendly artillery to direct counter-battery fire towards the enemy artillery.
The WLR also allows for remote operation, and data-linking for better situational awareness at higher echelons of the command hierarchy. The data can be automatically transmitted to a command center, and can communicate with higher echelons. The radar data can also be displayed on a remote screen to protect operators from any targeted attacks on the radar. The operators can also remotely change the scanning sector. Many radars can be networked together to work in tandem and increase the accuracy and provide more information.
truck platform . The trucks are manufactured by BEML
in India under license. The WLR is designed to operate in a high-density fire environment and has all weather capability, high mobility and quick reaction time. The system is a two vehicle configuration, with the primary sensor, processors, displays and control unit on a single vehicle, and a separate power vehicle to power the radar. The radar data can also be displayed remotely.
The Radar is designed to operate in harsh environments ranging from -20 to +55oC, in hot and humid conditions, and can be safely stored from -40 to +70oC. It can operate at high altitudes up to 16000 feet (4,876.8 m). Shock & vibration performance and resistance to EMI/EMC are according to international MIL standards. The WLR is designed for quick deployment and decamp, and can be ready for action within 30 minutes. In case of any incoming threats, the radar can be quickly moved out of the threat area.
-2003. The WLR was showcased at the Republic Day Parade in 2007. User Trials of the WLR began in 2005. The Army also used WLRs to further their "shoot and scoot" doctrine using self-propelled guns and artillery to loosen up defense before an offensive onslaught into hostile territory. By Mid-2006, the WLR was in advanced user acceptance trials and the radar was stated to be ready for production.
After user trials by the Indian Army in severe electronic clutter and “high density fire environment”, in June 2008, the WLR was accepted by the Indian Army
. 28 units are on order, and are being manufactured by BEL. A large number of components will be sourced from the private sector, including some Commercial off-the-shelf
(COTS) components from the international market. The WLR will eventually service the Army's requirement for 40-50 systems. Further improved versions of the WLR are being planned and designed, including longer range versions, as well as more compact variants for better operation and navigation over mountainous terrains.
Artillery
Originally applied to any group of infantry primarily armed with projectile weapons, artillery has over time become limited in meaning to refer only to those engines of war that operate by projection of munitions far beyond the range of effect of personal weapons...
locating Phased array radar developed by India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
. This counter-battery radar
Counter-battery radar
A counter-battery radar detects artillery projectiles fired by one or more guns, howitzers, mortars and rocket launchers and from their trajectories locates the position on the ground of the gun, etc., that fired it. Alternatively, or in addition, it may determine where the projectile will land...
is designed to detect and track incoming artillery and rocket fire to determine the point of origin for Counter-battery fire
Counter-battery fire
Counter-battery fire is a type of mission assigned to military artillery forces, which are given the task of locating and firing upon enemy artillery.-Background:...
.
The WLR has been jointly developed by DRDO's Bangalore
Bangalore
Bengaluru , formerly called Bengaluru is the capital of the Indian state of Karnataka. Bangalore is nicknamed the Garden City and was once called a pensioner's paradise. Located on the Deccan Plateau in the south-eastern part of Karnataka, Bangalore is India's third most populous city and...
based laboratory, LRDE
Electronics and Radar Development Establishment
Electronics and Radar Development Establishment is a laboratory of the Defence Research & Development Organization . Located in C.V. Raman Nagar, Bangalore its primary function is research and development of Radars and related technologies....
and the Government
Government of India
The Government of India, officially known as the Union Government, and also known as the Central Government, was established by the Constitution of India, and is the governing authority of the union of 28 states and seven union territories, collectively called the Republic of India...
owned Bharat Electronics Limited
Bharat Electronics Limited
Bharat Electronics Limited is a state-owned electronics company with about nine factories, and few regional offices in India. It is owned by the Indian Government & primarily manufactures advanced electronic products for the Indian Armed Forces.BEL is one of the eight PSUs under Ministry of...
(BEL). The sub-systems have been fabricated by BEL based on the DRDO designs and delivered to LRDE for integration.
History
The Indian army projected a requirement for fire-finding radars in the 1980s. As early as 1989, the Indian Army evaluated the American AN/TPQ-36/37 radars. However, these radars were not allowed to be sold, and the procurement process was stopped by the GovernmentGovernment of India
The Government of India, officially known as the Union Government, and also known as the Central Government, was established by the Constitution of India, and is the governing authority of the union of 28 states and seven union territories, collectively called the Republic of India...
. In February 1995, a Request for Proposal
Request for Proposal
A request for proposal is issued at an early stage in a procurement process, where an invitation is presented for suppliers, often through a bidding process, to submit a proposal on a specific commodity or service. The RFP process brings structure to the procurement decision and is meant to...
(RFP) was issued to five companies for procurement of 4 WLRs. Only Hughes (now Raytheon
Raytheon
Raytheon Company is a major American defense contractor and industrial corporation with core manufacturing concentrations in weapons and military and commercial electronics. It was previously involved in corporate and special-mission aircraft until early 2007...
) responded to the RFP. After trials, the radar was found to not be meeting the General Staff Quality Requirements (GSQRs) of the Indian Army, which were found to be too stringent, and were relaxed. At the same time, it was decided to consider development of an indigenous WLR by India's primary defense contractor, DRDO.
In September 1998, an RFP was issued for the urgent purchase of WLRs - An/TPQ-36/37 from Hughes (USA), Thomson CSF (France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
) and ISKARA of (Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...
). However, the American and French radars were withheld after sanctions were imposed after the Pokhran-II
Pokhran-II
Pokharan-II refers to test explosions of five nuclear devices, three on 11 May and two on 13 May 1998, conducted by India at the Pokhran test range. These nuclear tests resulted in a variety of sanctions against India by a number of major states....
Nuclear tests, and negotiations with the Ukrainian manufacturers came to no conclusion. Additionally, DRDO was not authorized to begin development of a WLR. These lacklustre efforts to obtain a WLR system were severely criticized by the Parliamentary Standing Committee on Defence.
Efforts to acquire such a system intensified after the Kargil War
Kargil War
The Kargil War ,, also known as the Kargil conflict, was an armed conflict between India and Pakistan that took place between May and July 1999 in the Kargil district of Kashmir and elsewhere along the Line of Control...
, where the Indian Army was severely disadvantaged by its lack of firefinding radars. While the Pakistani forces were equipped with American AN/TPQ-36 Firefinder radar
AN/TPQ-36 Firefinder radar
AN/TPQ-36 Firefinder is a mobile radar system manufactured by Northrop Grumman and ThalesRaytheonSystems . The system is a "weapon-locating radar", designed to detect and track incoming artillery and rocket fire to determine the point of origin for counterbattery fire...
s, India only had British Cymbeline mortar detecting radars, which were not suitable. Almost 80% of Indian casualties during the war resulted from enemy artillery fire, making such a radar critical.
To correct this weakness, in 2002, the Ministry of Defence issued an RFP to five manufacturers. With the lifting of sanctions in late-2001, the US Government offered to sell the AN/TPQ-37 radar to India under their Foreign Military Sales (FMS) programme for . 68 Crores each. In July 2002, India placed a $200 million USD order for 12 AN/TPQ-37 Firefinder radar
AN/TPQ-37 Firefinder radar
AN/TPQ-37 Firefinder is a mobile radar system manufactured by ThalesRaytheonSystems . The system is a long-range version of “weapon-locating radar,” designed to detect and track incoming artillery and rocket fire to determine the point of origin for counterbattery fire...
s. Initially, only 8 were ordered for $140 million USD, but the order was later increased to 12. The radars were integrated on BEML
BEML
Bharat Earth Movers Limited now known as BEML is an Indian Public Sector Undertaking, with headquarters in Bangalore. It manufactures a variety of heavy equipment, such as that used for earth moving, transport and mining....
-manufactured Tatra truck platforms. Delivery of all 12 radars was completed in May 2007. Concept design work on the WLR also accelerated in the aftermath of the Kargil War
Kargil War
The Kargil War ,, also known as the Kargil conflict, was an armed conflict between India and Pakistan that took place between May and July 1999 in the Kargil district of Kashmir and elsewhere along the Line of Control...
.
The WLR project was officially sanctioned in April 2002, with a sanctioned amount of . 20 Crores and an estimated completion time of 40 months. The first working prototype was to be ready by April 2004. The final project cost was $49 million USD. In January 2003, an intent for procurement of 28 WLRs was placed with BEL.
Design
The WLR is similar to the AN/TPQ-37 radarAN/TPQ-37 Firefinder radar
AN/TPQ-37 Firefinder is a mobile radar system manufactured by ThalesRaytheonSystems . The system is a long-range version of “weapon-locating radar,” designed to detect and track incoming artillery and rocket fire to determine the point of origin for counterbattery fire...
in design and performance but is reportedly more user friendly. It is a passive phased array
Phased array
In wave theory, a phased array is an array of antennas in which the relative phases of the respective signals feeding the antennas are varied in such a way that the effective radiation pattern of the array is reinforced in a desired direction and suppressed in undesired directions.An antenna array...
radar, derived from the Rajendra Radar
Rajendra Radar
Rajendra is a passive Phased Array Radar developed by the Indian DRDO. It is a multifunction radar, capable of surveillance, tracking and engaging low radar cross section targets...
(which is the fire control radar for the Akash missile
Akash missile
Akash is India's medium range surface-to-air missile defense system developed by the Defence Research and Development Organisation and Bharat Electronics Limited as part of the Integrated Guided Missile Development Program. The missile can target aircraft up to 30 km away, at altitudes up to...
system). During tests of the Akash missile
Akash missile
Akash is India's medium range surface-to-air missile defense system developed by the Defence Research and Development Organisation and Bharat Electronics Limited as part of the Integrated Guided Missile Development Program. The missile can target aircraft up to 30 km away, at altitudes up to...
at Chandipur, engineers noticed the Rajendra radar was able to detect and track artillery
Artillery
Originally applied to any group of infantry primarily armed with projectile weapons, artillery has over time become limited in meaning to refer only to those engines of war that operate by projection of munitions far beyond the range of effect of personal weapons...
shells being test fired at a nearby range. Based on this observation, LRDE scientists were able to adapt the Rajendra Array into the WLR.
The WLR Array is an electronically-steered radar, meaning the radar antenna does not move while in operation. The radar can electronically scan a +/-45º range of azimuths for incoming rocket, artillery and mortar fire. The radar antenna is slewable up to +/-135º within 30 seconds, which gives the WLR the ability to quickly change its scanning sector, and provides it 360o scan capability. The Coherent TWT based transmitter of the WLR emits 40 kW of power.
Tracking of the target is done with monopulse signals with Pulse compression
Pulse compression
Pulse compression is a signal processing technique mainly used in radar, sonar and echography to increase the range resolution as well as the signal to noise ratio...
, which improves the radar's LPI
Low probability of intercept
A low-probability-of-intercept radar is designed to be difficult to detect by passive radar detection equipment while it is searching for a target or engaged in target tracking...
. The radar processors conduct real time signal processing of the received signals. The weapon locating algorithm is an adaptive algorithm based on a modified version of the Runge-Kutta method, and uses Constant false alarm rate
Constant false alarm rate
Constant false alarm rate detection refers to a common form of adaptive algorithm used in radar systems to detect target returns against a background of noise, clutter and interference.Other detection algorithms are not adaptive...
(CFAR) techniques to detect the target accurately. The operator can choose the CFAR technique to be used to maximize the accuracy of information. The data is processed on a programmable digital signal processor
Digital signal processor
A digital signal processor is a specialized microprocessor with an architecture optimized for the fast operational needs of digital signal processing.-Typical characteristics:...
using a modified extended Kalman filter
Kalman filter
In statistics, the Kalman filter is a mathematical method named after Rudolf E. Kálmán. Its purpose is to use measurements observed over time, containing noise and other inaccuracies, and produce values that tend to be closer to the true values of the measurements and their associated calculated...
, with two filters - one with 6 states, and another with 7 states. Clutter rejection is achieved through Moving target indication
Moving target indication
Moving target indication is a mode of operation of a radar to discriminate a target against clutter. In contrast to another mode, stationary target indication, it takes an advantage of the fact that the target moves with respect to stationary clutter. The most common approach takes advantage of...
(MTI), Airborne MTI (AMTI) and Fast Fourier Transform
Fast Fourier transform
A fast Fourier transform is an efficient algorithm to compute the discrete Fourier transform and its inverse. "The FFT has been called the most important numerical algorithm of our lifetime ." There are many distinct FFT algorithms involving a wide range of mathematics, from simple...
(FFT).
Information is displayed on ruggedised
Rugged computer
A rugged computer is a computer specifically designed to reliably operate in harsh usage environments and conditions, such as strong vibrations, extreme temperatures and wet or dusty conditions...
power PCs on a high resolution multi-mode colour display. The data is displayed in real-time and can be overlayed on a 3D digital map. The WLR can store a 100 km x 100 km size digital map for display at any time. Other modes include Plan position indicator
Plan position indicator
The plan position indicator , is the most common type of radar display. The radar antenna is usually represented in the center of the display, so the distance from it and height above ground can be drawn as concentric circles...
(PPI) display, RHI displays, etc. Up to 99 weapon locations can be stored and tracked at any time and can be transmitted to the command centre.
Operation
The WLR is designed to detect and track incoming artillery rounds, mortar and rockets and locate their launchers. In its secondary role, it can also track and observe the fall of shot from friendly guns and provide fire corrections to counter-battery fire.The detection range for large caliber artillery rounds is up to 30 km, and increases to 40 km for unguided rockets. The robust design of the radar array and algorithms allows the WLR to effectively operate even in a high density fire environment, in severe clutter and interference (jamming) conditions. Up to 7 targets can be tracked simultaneously. The radar can track rounds fired at both low and high angles, and at all aspect angles - from behind or towards the radar, or at an oblique angle to the array. The WLR features adaptive radar resource scheduling to increase efficiency and reliability.
At a given position, the radar can scan for targets in one quadrant, encompassing a 90o sector. The array can electronically scan up to +/-45o from its mean bearing. Additionally, for 360o coverage from a given position, the whole array can be rotated by 135o on either side within 30 seconds to quickly change the scanning sector in response to threats.
Upon detecting an incoming round, the automatically acquires and classifies the threat and initiates a track sequence, while continuing to search for new targets. The incoming round's trajectory is tracked, and a computer program analyzes the track data and then extrapolates the round's point of origin. This calculated point of origin is then reported to the radar operator, thus allowing friendly artillery to direct counter-battery fire towards the enemy artillery.
The WLR also allows for remote operation, and data-linking for better situational awareness at higher echelons of the command hierarchy. The data can be automatically transmitted to a command center, and can communicate with higher echelons. The radar data can also be displayed on a remote screen to protect operators from any targeted attacks on the radar. The operators can also remotely change the scanning sector. Many radars can be networked together to work in tandem and increase the accuracy and provide more information.
Platform
The WLR is configured on a wheeled Tatra 8x8Eight-wheel drive
Eight-wheel drive, 8WD, or 8x8 is an eight-wheeled vehicle with a drivetrain that allows all eight wheels to receive power from the engine simultaneously.Some severe/extreme duty semi tractors may have this configuration...
truck platform . The trucks are manufactured by BEML
BEML
Bharat Earth Movers Limited now known as BEML is an Indian Public Sector Undertaking, with headquarters in Bangalore. It manufactures a variety of heavy equipment, such as that used for earth moving, transport and mining....
in India under license. The WLR is designed to operate in a high-density fire environment and has all weather capability, high mobility and quick reaction time. The system is a two vehicle configuration, with the primary sensor, processors, displays and control unit on a single vehicle, and a separate power vehicle to power the radar. The radar data can also be displayed remotely.
The Radar is designed to operate in harsh environments ranging from -20 to +55oC, in hot and humid conditions, and can be safely stored from -40 to +70oC. It can operate at high altitudes up to 16000 feet (4,876.8 m). Shock & vibration performance and resistance to EMI/EMC are according to international MIL standards. The WLR is designed for quick deployment and decamp, and can be ready for action within 30 minutes. In case of any incoming threats, the radar can be quickly moved out of the threat area.
Status
A basic prototype of the WLR was first unveiled at Aero IndiaAero India
Aero India is a biennial air show and aviation exhibition held in Bangalore, India at the Yelahanka Air Force Station. It is organized by Defence Exhibition Organisation, the Ministry of Defence and is held in association with the Defence Research and Development Organisation , the Indian Air Force...
-2003. The WLR was showcased at the Republic Day Parade in 2007. User Trials of the WLR began in 2005. The Army also used WLRs to further their "shoot and scoot" doctrine using self-propelled guns and artillery to loosen up defense before an offensive onslaught into hostile territory. By Mid-2006, the WLR was in advanced user acceptance trials and the radar was stated to be ready for production.
After user trials by the Indian Army in severe electronic clutter and “high density fire environment”, in June 2008, the WLR was accepted by the Indian Army
Indian Army
The Indian Army is the land based branch and the largest component of the Indian Armed Forces. With about 1,100,000 soldiers in active service and about 1,150,000 reserve troops, the Indian Army is the world's largest standing volunteer army...
. 28 units are on order, and are being manufactured by BEL. A large number of components will be sourced from the private sector, including some Commercial off-the-shelf
Commercial off-the-shelf
In the United States, Commercially available Off-The-Shelf is a Federal Acquisition Regulation term defining a nondevelopmental item of supply that is both commercial and sold in substantial quantities in the commercial marketplace, and that can be procured or utilized under government contract...
(COTS) components from the international market. The WLR will eventually service the Army's requirement for 40-50 systems. Further improved versions of the WLR are being planned and designed, including longer range versions, as well as more compact variants for better operation and navigation over mountainous terrains.
Performance
- Range:
- >81 mm Mortars: 2–20 km
- >105 mm Guns: 2–30 km
- Unguided Rockets: 4–40 km
- Elevation Coverage: -5 to 75o
- Azimuth Coverage: +/- 45o mean settable bearing
- Slewability: +/- 135o within 30 seconds.
- Targets Tracking: 7 simultaneously (maximum)
- Firing angles: Both High & Low
- Aspect Angles: 0-180o
Technical Specifications
- Instrumented Range: 50 km
- Frequency Band: C bandC bandThe C band is a name given to certain portions of the electromagnetic spectrum, including wavelengths of microwaves that are used for long-distance radio telecommunications. The IEEE C-band - and its slight variations - contains frequency ranges that are used for many satellite communications...
- Probability of:
- Detection: 0.9
- False Alarm: 10−6
- Weapon Locations: 99 stored (maximum)
- Digital Map Storage: 100 x 100 km
Environmental Specifications
- Operating temperatureOperating temperatureAn operating temperature is the temperature at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the device function and application context, and ranges from the minimum operating temperature to the...
: -20 to +55oC - Storage Temperature: -40 to +70oC
- Damp Heat: 95% RHRelative humidityRelative humidity is a term used to describe the amount of water vapor in a mixture of air and water vapor. It is defined as the partial pressure of water vapor in the air-water mixture, given as a percentage of the saturated vapor pressure under those conditions...
at 40oC - Operational Altitude: Up to 16000 feet (4,876.8 m)
See also
- Counter-battery radarCounter-battery radarA counter-battery radar detects artillery projectiles fired by one or more guns, howitzers, mortars and rocket launchers and from their trajectories locates the position on the ground of the gun, etc., that fired it. Alternatively, or in addition, it may determine where the projectile will land...
- AN/TPQ-36 Firefinder radarAN/TPQ-36 Firefinder radarAN/TPQ-36 Firefinder is a mobile radar system manufactured by Northrop Grumman and ThalesRaytheonSystems . The system is a "weapon-locating radar", designed to detect and track incoming artillery and rocket fire to determine the point of origin for counterbattery fire...
- AN/TPQ-37 Firefinder radarAN/TPQ-37 Firefinder radarAN/TPQ-37 Firefinder is a mobile radar system manufactured by ThalesRaytheonSystems . The system is a long-range version of “weapon-locating radar,” designed to detect and track incoming artillery and rocket fire to determine the point of origin for counterbattery fire...
- ARTHUR (military)ARTHUR (military)ARTHUR is an abbreviation for mobile "Artillery Hunting Radar" system developed in Sweden. This field artillery acquisition radar was developed for the primary role as the core element of a brigade or division level counter battery sensor system. It can also be used for peace support operations...
- Red Color
External links
- Weapon Locating Radar on DRDO website.
- WLR Poster from DRDO
- Picture of the WLR from Aero IndiaAero IndiaAero India is a biennial air show and aviation exhibition held in Bangalore, India at the Yelahanka Air Force Station. It is organized by Defence Exhibition Organisation, the Ministry of Defence and is held in association with the Defence Research and Development Organisation , the Indian Air Force...
-2003.
