Martian2
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China's DWL002 Emitter Locating System (ELS) is a big evolutionary leap beyond the original Russian Tamara and improved Vera ELS systems.
The key feature is the addition of a second receiver. This provides the Chinese DWL002 ELS with two important advantages.
Firstly, a single DWL002 unit can use triangulation to pinpoint the exact location of an enemy aircraft. In contrast, a single Russian receiver can only identify the direction but not the precise location of an enemy aircraft.
Secondly, China's DWL002 has two receivers that permit interferometry. Though this does not increase the range, the resolution/sensitivity is equivalent to a receiver that is almost the length of the mast.
I have included two citations below to show that China has researched interferometry, including X-band radar.
If two Chinese DWL002 are linked via tight wireless transmission or fiber-optic cables to create a super-interferometer, the resolution would be incredible. If multiple DWL002 are interconnected and the data is processed by computers, the result is an interferometer of unimaginable sensitivity.
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PLA Systems | CETC DWL002 Passive Detection System | Air Power Australia
"PLA Systems | CETC DWL002 Passive Detection System
DWL002 antenna arrangement.
The recently disclosed DWL002 is a modern and technically sophisticated digital Emitter Locating System, which builds on ideas employed in the earlier YLC-20 ELS. While design employs much the same DTOA and Angle Of Arrival [AOA] techniques as the much older Russian, Ukrainian and Czech ELS systems, the DWL002 introduces an important innovation, which is the use of paired primary wideband apertures, displaced in elevation. The resulting phase and time differences between the upper and lower antennas permit heightfinding, otherwise problematic in earlier single aperture designs.
The primary apertures are housed under cylindrical radomes, in an arrangement similar to the KRTP-91 Tamara and ERA Vera systems.
The lower primary aperture is on a telescoping mast, the upper primary aperture on the articulated folding main mast, which employs hydraulic actuators.
Below the upper primary aperture is a package of steerable parabolic antennas, likely operating in the upper X-band or Ku-band. These are employed to provide high data rate links between the three or four networked DWL002 systems when deployed.
The aft of the equipment container also mounts three Yagi antennas, the purpose of which has not been disclosed. It is most likely that these are employed for datalinking target track data from the networked DWL002 systems to other air defence assets.
The system is carried on a North Benz ND1260 (Mercedes-Benz NG 80) 6 x 6 military truck, common to recent radar designs such as the YLC-2V, JY-11B, JYL-1, YLC-18, Type 120, Type 305A and Type 305B. This will result in similar onroad and offroad performance.
The strategic significance of the DWL002 is that it is the first DTOA technology ELS which has been designed from the outset with the intention of providing robust heightfinding capability when passively tracking an emitting target. The ability to generate near-realtime or soft realtime 3D target tracks would be especially valuable in supporting SAM systems like the S-300PMU2 or HQ-9, as this could be employed to cue the SAM engagement radar very precisely to the inbound target. Should the accuracy of the ELS be sufficiently high, it could be employed to generate post-launch midcourse tracking corrections for outbound SAMs.
The CETC brochure describes the system thus:
'DWL002 Passive Detection System, also called as passive radar, is mainly used in air-defense or seashore monitoring to perform the detection to perform the detection and location to airborne, shipborne or landbased emitters in complex electromagnetic environment and display the target flight path in real time. The system can also operate together with active detection system to form a mutual supplementary surveillance network.
Typical configuration of DVL002 Passive Detection 'system is composed of three reconnaissance stations. One of them serves as master station and the other two as slave stations. The system can be expandable to four station configuration with perfect performance of full spatial coverage and altitude information of air target. Each station is carried by an individual vehicle.
Main Functions:
* Realtime & Accurate Location and Tracking
* Signal Analysis and Identification
* Long Range Detection and Early Warning
Main Features:
* Passive
* Real Time
* Very Good Mobility
DWL002 Passive Detection System is a three station configuration (expandable to four station configuration). Each station. including antenna and power generator. is housed and carried by one vehicle. which ensures the good mobility of the system
* Remote Control
* Advanced techniques
Long base line time difference of arrival (TDOA) location technique combined with AOA: Wideband digitized receiver technique; Multilevel correlation processing technique with good flight track processing result: Automatic set up. Chassis leveling techniques and automatic north calibration technique to ensure fast deployment and flexible operation.'"
DWL002 CONOPS diagram. [Note: CONOPS stands for Concept of Operations]
DWL002 console display of target track.
[Note: DTOA stands for Differential Time of Arrival]
----------
Assessment of Polarimetric and Interferometric Image Quality for Chinese Domestic X-Band Airborne SAR System
----------
Applying SAR Interferometry for Ground Deformation Detection in China
The key feature is the addition of a second receiver. This provides the Chinese DWL002 ELS with two important advantages.
Firstly, a single DWL002 unit can use triangulation to pinpoint the exact location of an enemy aircraft. In contrast, a single Russian receiver can only identify the direction but not the precise location of an enemy aircraft.
Secondly, China's DWL002 has two receivers that permit interferometry. Though this does not increase the range, the resolution/sensitivity is equivalent to a receiver that is almost the length of the mast.
I have included two citations below to show that China has researched interferometry, including X-band radar.
If two Chinese DWL002 are linked via tight wireless transmission or fiber-optic cables to create a super-interferometer, the resolution would be incredible. If multiple DWL002 are interconnected and the data is processed by computers, the result is an interferometer of unimaginable sensitivity.
----------
PLA Systems | CETC DWL002 Passive Detection System | Air Power Australia
"PLA Systems | CETC DWL002 Passive Detection System
DWL002 antenna arrangement.
The recently disclosed DWL002 is a modern and technically sophisticated digital Emitter Locating System, which builds on ideas employed in the earlier YLC-20 ELS. While design employs much the same DTOA and Angle Of Arrival [AOA] techniques as the much older Russian, Ukrainian and Czech ELS systems, the DWL002 introduces an important innovation, which is the use of paired primary wideband apertures, displaced in elevation. The resulting phase and time differences between the upper and lower antennas permit heightfinding, otherwise problematic in earlier single aperture designs.
The primary apertures are housed under cylindrical radomes, in an arrangement similar to the KRTP-91 Tamara and ERA Vera systems.
The lower primary aperture is on a telescoping mast, the upper primary aperture on the articulated folding main mast, which employs hydraulic actuators.
Below the upper primary aperture is a package of steerable parabolic antennas, likely operating in the upper X-band or Ku-band. These are employed to provide high data rate links between the three or four networked DWL002 systems when deployed.
The aft of the equipment container also mounts three Yagi antennas, the purpose of which has not been disclosed. It is most likely that these are employed for datalinking target track data from the networked DWL002 systems to other air defence assets.
The system is carried on a North Benz ND1260 (Mercedes-Benz NG 80) 6 x 6 military truck, common to recent radar designs such as the YLC-2V, JY-11B, JYL-1, YLC-18, Type 120, Type 305A and Type 305B. This will result in similar onroad and offroad performance.
The strategic significance of the DWL002 is that it is the first DTOA technology ELS which has been designed from the outset with the intention of providing robust heightfinding capability when passively tracking an emitting target. The ability to generate near-realtime or soft realtime 3D target tracks would be especially valuable in supporting SAM systems like the S-300PMU2 or HQ-9, as this could be employed to cue the SAM engagement radar very precisely to the inbound target. Should the accuracy of the ELS be sufficiently high, it could be employed to generate post-launch midcourse tracking corrections for outbound SAMs.
The CETC brochure describes the system thus:
'DWL002 Passive Detection System, also called as passive radar, is mainly used in air-defense or seashore monitoring to perform the detection to perform the detection and location to airborne, shipborne or landbased emitters in complex electromagnetic environment and display the target flight path in real time. The system can also operate together with active detection system to form a mutual supplementary surveillance network.
Typical configuration of DVL002 Passive Detection 'system is composed of three reconnaissance stations. One of them serves as master station and the other two as slave stations. The system can be expandable to four station configuration with perfect performance of full spatial coverage and altitude information of air target. Each station is carried by an individual vehicle.
Main Functions:
* Realtime & Accurate Location and Tracking
* Signal Analysis and Identification
* Long Range Detection and Early Warning
Main Features:
* Passive
* Real Time
* Very Good Mobility
DWL002 Passive Detection System is a three station configuration (expandable to four station configuration). Each station. including antenna and power generator. is housed and carried by one vehicle. which ensures the good mobility of the system
* Remote Control
* Advanced techniques
Long base line time difference of arrival (TDOA) location technique combined with AOA: Wideband digitized receiver technique; Multilevel correlation processing technique with good flight track processing result: Automatic set up. Chassis leveling techniques and automatic north calibration technique to ensure fast deployment and flexible operation.'"
DWL002 CONOPS diagram. [Note: CONOPS stands for Concept of Operations]
DWL002 console display of target track.
[Note: DTOA stands for Differential Time of Arrival]
----------
Assessment of Polarimetric and Interferometric Image Quality for Chinese Domestic X-Band Airborne SAR System
----------
Applying SAR Interferometry for Ground Deformation Detection in China
