ILLUMINATO
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Can Kill J-20 & PAKFA/T-50, Says Eurofighter
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Martian2
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Take a careful look at the second diagram from Australia Air Power's nine-radar band simulation. In X-band, the J-20 Mighty Dragon has a radar signature of -30db (light purple) to -60db (white). A J-20 cannot be detected beyond 13.5km.
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X band - Wikipedia, the free encyclopedia
"X band is often used in modern radars. The shorter wavelengths of the X band allow for higher resolution imagery from high-resolution imaging radars for target identification and discrimination."
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Australia Air Power: J-20 is a "genuine Very Low Observable design"
J-20 Mighty Dragon is a "genuine Very Low Observable design" except for round engine nozzles, which can be fixed.
The Chengdu J-20: Peace in Our Time?
"This study has therefore established through Physical Optics simulation across nine radio-frequency bands, that no fundamental obstacles exist in the shaping design of the J-20 prototype precluding its development into a genuine Very Low Observable design.
Above: L-band RCS, below X-band RCS head on, both in PCSR format (M.J. Pelosi).
Engineers and Scientists who work in ‘stealth’ (AKA ‘Low Observable’
designs have a way for explaining it to lay people: ‘Stealth’ is achieved by Shaping, Shaping, Shaping and Materials (Denys Overholser).
The F-22A is clearly well shaped for low observability above about 500 MHz, and from all important aspects. The J-20 has observed the ‘Shaping, Shaping, Shaping’ imperative, except for the axisymmetric nozzles, and some curvature of the sides that smears a strong, but very narrow specular return into something of a more observable fan. The X-35 mostly observed the ‘Shaping, Shaping, Shaping’ rule, but since then, to quote a colleague, ‘hideous lumps, bumps, humps and warts’ have appeared on the JSF to disrupt the shaping imperative, forcing excessive reliance on materials, which are at the rear-end of the path to ‘Low Observability’.
While discussing ‘rear-ends’, both the F-35 and the J-20 have large signature contributions from their jet nozzles. However, the difference is much like the proverbial ‘Ham Omelette’: the F-35 Pig is committed, but the J-20 Chicken is a participant. If the Chinese decide that rear sector Low Observability is tactically and strategically important, they are at the design stage where they can copy the F-22A nozzle design for the production configuration of the J-20."
[Note: Thank you to HouShanghai and 蓝胖 for the picture.]
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Ground-based radar can detect F-22/J-20 at 13.5 km, Rafale at 135 km, T-50 at 178 km
The EADS mobile ground-based "3D Radar System DR 174" can detect a F-22/J-20 at approximately 13.5 km, French Rafale at 135 km, and a Russian T-50 at 178 km.
The DR 174 only has 24 kilowatts of peak power and it operates in the L-band. Obviously, a permanent ground-based radar or AWACS will have more peak power, more radar bands (e.g. X-band, S-band, L-band, etc.), more powerful computers, better discriminating software, better-trained personnel, etc.
My calculations:
According to GlobalSecurity (see one of my earlier posts), the French Rafale has a RCS of 1 m2. We know that "the detection range [of the DR 174] against tactical aircraft ("Swerling 1"- targets) with a radar cross section (RCS) of 1 m² is 135 km at a probability of detection of 90%."
We know that the "reflected power density at the radar receiver" is proportional to the fourth-root of the distance from the emitting radar or RCS (see Radar cross-section - Wikipedia, the free encyclopedia).
According to GlobalSecurity, the F-22 (and my estimate of J-20's front-profile) has a RCS of 0.0001. The F-22's/J-20's RCS is 10,000 times smaller than the French Rafale. The fourth-root of 10,000 is 10. Therefore, the detection range of the F-22/J-20 in comparison to the French Rafale is 13.5 km (e.g. 135 km/factor of 10 from much smaller RCS = 13.5 km).
Since the Russian T-50, with exposed engine compressor blades, has a RCS greater than the French Rafale's 1 m2, I have estimated the Russian T-50 RCS to be about 3 m2. The fourth-root of 3 is 1.316. Therefore, the detection range of the Russian T-50 in comparison to the French Rafale is 178 km (e.g. 135 km * factor of 1.316 from larger RCS = 178 km).
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Radar Basics
3D Radar System DR 174
Bild 1: © EADS
The 3D radar system DR 174 is a highly mobile short/mid range surveillance radar operating in the L-Band. The radar system can be used as coastal radar for sea and air surveillance or as "gap fillers" for areas longer radars do not cover. The system can be integrated into existing defence networks, anti-aircraft (AA) weapon systems and other networks. It can also serve as a "stand alone" control center due the fully integrated state of the art working positions. A wide range of ECCM features and excellent clutter suppression ensure the detection of small targets even in a very hostile environment.
This 3D radar system operates in L-Band using a stacked beam active planar antenna. It features up to 8 elevation beams on receive. The system is designed in fully solid state technology.
The DR 174 Doppler radar features
* High unambiguous radial velocity due to appropriate pulse repetition frequency (PRF) stagger
* Frequency diversity
* High doppler resolution
* Detecting of tangential flying targets due to self learning ground clutter map
The detection range against tactical aircrafts ("Swerling 1"- targets) with a radar cross section (RCS) of 1 m² is 135 km at a probability of detection of 90%. The detection range against tactical ballistic missiles with a radar cross section (RCS) of 0.1 m² is 75 km at the same conditions.
Waveform selection
The following statements highlight the capabilities of the DR 174 waveform selection:
* Different waveforms for various radar modes
* Non-linear frequency modulation
* Burst-to-Burst frequency change
* Burst-to-Burst pulse repetition frequency change
* Dual pulse for near range covering
* High range resolution waveforms
ECCM features
The electronic counter counter measures used by the DR 174 are:
* Frequency change from Burst-to-Burst
* Moving target detection processing with Doppler selective constant false alarm rate
* Low antenna sidelobes in azimuth and elevation
* Sidelobe blanking (SLB) (optional)
* Large receive dynamic range
* Selectable beam-processing
* Automatic jamming avoidance circuit (AJAC)
Clutter rejection
Excellent clutter suppression and detection of small targets in any type of clutter (ground- and rainclutter, seaclutter, chaff and angles) by:
* Very stable solid state transmitter
* Frequency agile synthesizer
* Moving target detection Doppler processing in frequency domain (sub clutter visibility)
* Ordered statistic constant false alarm rate in time domain
* High resolution clutter map
* Decreasing the size of resolution cell of radar (pulse compression with time sidelobes <45 dB)
* Matched detection threshold for each Doppler channel
* Tilting the antenna to higher elevation angles
ARM protection
Protecting against Anti Radar Missiles is supported by:
* LPT due to low transmitter peak power
* Transmitter silent sectors
* Very low antenna sidelobes
* Inherent system protection due to radar operating frequency band (L-Band)
The system consists of four major components the sensor (antenna group consisting of primary ans secondary radar), the Signal Processing (SiP) shelter, the Operations and Missions Control (OMC) shelter and the generator for reliable power supply in mobile deployment.
Also available is the DR 184, the long range version (400 km) of DR 174.
Figure 2: The concept of the DR 174 sensor
----------
X band - Wikipedia, the free encyclopedia
"X band is often used in modern radars. The shorter wavelengths of the X band allow for higher resolution imagery from high-resolution imaging radars for target identification and discrimination."
----------
Australia Air Power: J-20 is a "genuine Very Low Observable design"
J-20 Mighty Dragon is a "genuine Very Low Observable design" except for round engine nozzles, which can be fixed.
The Chengdu J-20: Peace in Our Time?
"This study has therefore established through Physical Optics simulation across nine radio-frequency bands, that no fundamental obstacles exist in the shaping design of the J-20 prototype precluding its development into a genuine Very Low Observable design.
Above: L-band RCS, below X-band RCS head on, both in PCSR format (M.J. Pelosi).
Engineers and Scientists who work in ‘stealth’ (AKA ‘Low Observable’
designs have a way for explaining it to lay people: ‘Stealth’ is achieved by Shaping, Shaping, Shaping and Materials (Denys Overholser).The F-22A is clearly well shaped for low observability above about 500 MHz, and from all important aspects. The J-20 has observed the ‘Shaping, Shaping, Shaping’ imperative, except for the axisymmetric nozzles, and some curvature of the sides that smears a strong, but very narrow specular return into something of a more observable fan. The X-35 mostly observed the ‘Shaping, Shaping, Shaping’ rule, but since then, to quote a colleague, ‘hideous lumps, bumps, humps and warts’ have appeared on the JSF to disrupt the shaping imperative, forcing excessive reliance on materials, which are at the rear-end of the path to ‘Low Observability’.
While discussing ‘rear-ends’, both the F-35 and the J-20 have large signature contributions from their jet nozzles. However, the difference is much like the proverbial ‘Ham Omelette’: the F-35 Pig is committed, but the J-20 Chicken is a participant. If the Chinese decide that rear sector Low Observability is tactically and strategically important, they are at the design stage where they can copy the F-22A nozzle design for the production configuration of the J-20."
[Note: Thank you to HouShanghai and 蓝胖 for the picture.]
----------
Ground-based radar can detect F-22/J-20 at 13.5 km, Rafale at 135 km, T-50 at 178 km
The EADS mobile ground-based "3D Radar System DR 174" can detect a F-22/J-20 at approximately 13.5 km, French Rafale at 135 km, and a Russian T-50 at 178 km.
The DR 174 only has 24 kilowatts of peak power and it operates in the L-band. Obviously, a permanent ground-based radar or AWACS will have more peak power, more radar bands (e.g. X-band, S-band, L-band, etc.), more powerful computers, better discriminating software, better-trained personnel, etc.
My calculations:
According to GlobalSecurity (see one of my earlier posts), the French Rafale has a RCS of 1 m2. We know that "the detection range [of the DR 174] against tactical aircraft ("Swerling 1"- targets) with a radar cross section (RCS) of 1 m² is 135 km at a probability of detection of 90%."
We know that the "reflected power density at the radar receiver" is proportional to the fourth-root of the distance from the emitting radar or RCS (see Radar cross-section - Wikipedia, the free encyclopedia).
According to GlobalSecurity, the F-22 (and my estimate of J-20's front-profile) has a RCS of 0.0001. The F-22's/J-20's RCS is 10,000 times smaller than the French Rafale. The fourth-root of 10,000 is 10. Therefore, the detection range of the F-22/J-20 in comparison to the French Rafale is 13.5 km (e.g. 135 km/factor of 10 from much smaller RCS = 13.5 km).
Since the Russian T-50, with exposed engine compressor blades, has a RCS greater than the French Rafale's 1 m2, I have estimated the Russian T-50 RCS to be about 3 m2. The fourth-root of 3 is 1.316. Therefore, the detection range of the Russian T-50 in comparison to the French Rafale is 178 km (e.g. 135 km * factor of 1.316 from larger RCS = 178 km).
----------
Radar Basics
3D Radar System DR 174
Bild 1: © EADS
The 3D radar system DR 174 is a highly mobile short/mid range surveillance radar operating in the L-Band. The radar system can be used as coastal radar for sea and air surveillance or as "gap fillers" for areas longer radars do not cover. The system can be integrated into existing defence networks, anti-aircraft (AA) weapon systems and other networks. It can also serve as a "stand alone" control center due the fully integrated state of the art working positions. A wide range of ECCM features and excellent clutter suppression ensure the detection of small targets even in a very hostile environment.
This 3D radar system operates in L-Band using a stacked beam active planar antenna. It features up to 8 elevation beams on receive. The system is designed in fully solid state technology.
The DR 174 Doppler radar features
* High unambiguous radial velocity due to appropriate pulse repetition frequency (PRF) stagger
* Frequency diversity
* High doppler resolution
* Detecting of tangential flying targets due to self learning ground clutter map
The detection range against tactical aircrafts ("Swerling 1"- targets) with a radar cross section (RCS) of 1 m² is 135 km at a probability of detection of 90%. The detection range against tactical ballistic missiles with a radar cross section (RCS) of 0.1 m² is 75 km at the same conditions.
Waveform selection
The following statements highlight the capabilities of the DR 174 waveform selection:
* Different waveforms for various radar modes
* Non-linear frequency modulation
* Burst-to-Burst frequency change
* Burst-to-Burst pulse repetition frequency change
* Dual pulse for near range covering
* High range resolution waveforms
ECCM features
The electronic counter counter measures used by the DR 174 are:
* Frequency change from Burst-to-Burst
* Moving target detection processing with Doppler selective constant false alarm rate
* Low antenna sidelobes in azimuth and elevation
* Sidelobe blanking (SLB) (optional)
* Large receive dynamic range
* Selectable beam-processing
* Automatic jamming avoidance circuit (AJAC)
Clutter rejection
Excellent clutter suppression and detection of small targets in any type of clutter (ground- and rainclutter, seaclutter, chaff and angles) by:
* Very stable solid state transmitter
* Frequency agile synthesizer
* Moving target detection Doppler processing in frequency domain (sub clutter visibility)
* Ordered statistic constant false alarm rate in time domain
* High resolution clutter map
* Decreasing the size of resolution cell of radar (pulse compression with time sidelobes <45 dB)
* Matched detection threshold for each Doppler channel
* Tilting the antenna to higher elevation angles
ARM protection
Protecting against Anti Radar Missiles is supported by:
* LPT due to low transmitter peak power
* Transmitter silent sectors
* Very low antenna sidelobes
* Inherent system protection due to radar operating frequency band (L-Band)
The system consists of four major components the sensor (antenna group consisting of primary ans secondary radar), the Signal Processing (SiP) shelter, the Operations and Missions Control (OMC) shelter and the generator for reliable power supply in mobile deployment.
Also available is the DR 184, the long range version (400 km) of DR 174.
Figure 2: The concept of the DR 174 sensor
Kiss_of_the_Dragon
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Yeah..India should abandon pursuing T-50 program and buy Eurofighter instead 
ganesh177
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Emmie
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You took it wrong lad... I in fact valued PAK-FA... Anyways, thanks for those words of wisdom.
Backbencher
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The fact of the matter is that we will have pakfa and we might even have eurofighter.......
shree835
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Believe India Do not needs PAKISTANI or CHINESE Expert advice for anything or anywhere…Please Keep your Valuable advice for you and your country.
NeutralCitizen
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This was posted a while ago.
hembo
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What's wrong with you guys.. This is an international forum where posters are from all nationality. Everyone is entitled to their opinion & free to express it wherever they like. One may refute one's views & that's how these threads progress. Based on CIVIL debates & discussions.
That's the modus operandi of this forum.. I cannot fathom these high headedness, both from Indian as well as well as Pakistani posters.
Killswitch
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Set up a dogfight and see who wins.... anything said until that day is BS.
Gandhi G in da house
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By looks of things we are going to end up having both .
He was probably just making fun of eurofighter's marketing, with a sarcastic comment, and not pretending to advice India. Don't be so trigger happy, and be civil.
Gandhi G in da house
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Dude you are on a Pakistani forum . Please always keep that in mind.
