F-35 Joint Strike Fighter

BON PLAN

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Your current one too don't like muzzies much , well if france correct it's course there is a hope for whole Europe .

When france sneezes ,whole europe catches cold .

Any news about possible scorpene deal in your outlets , some are expecting some development in may 2021 meeting
The problem is some muslims don't like us ! but they like our social treatments, unemployment coverage...
Some hate France but are more and more to come in... We can't continue like that.
 

omaebakabaka

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USA had a lead with F117 and F22.
F35 is simply too complexe. The main error was to study a single jet for 3 services. Remove the B model and you have probably a decent bird.
And the weapon system software was intended from the beginning to be able to do all (AtoA, AtoG, Sea assault, communication node, anti missile platform...). They decided not to move away by small steps. The result is a huge software, made by too many teams without the proper management and with so many releases that it's a full mess. They solve a problem, another occur.
Yes, in the software world....time tested keep it simple and do one thing and do it best at the core are still the most efficient concepts. This plane is just at the limits and hard to foresee it as an extendeable platform as everything seems to be at the limit already
 

omaebakabaka

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Just wait 2022, or at the latest 2027. The right wing will take the presidency.... End of the left aisle game.
As the Japanese say "mangaichi" 10000 to 1 odds really. These kind of problems are generational and above 5% muslim minority is a ticking bomb no matter how you look at it. Macaroni just talks and dilutes everything by the time it comes out. Rightwing does not mean they are not corrupt or global behind the scenes. I think France needs an Orban just like India needs Yogi like ones....not violent but fair and believe in preserving their centuries old traditions.
 

StealthFlanker

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https://itech.aorti.ru/upload/iblock/467/rti_ii_4_19_2017.pdf page 24. Sintering approaches are also used layers of structure or combining through polyimide layers and selective epitaxial growth of active layers in areas formed topology on the plate. Here flexibility of technologies is combined with high technology and complexity, the need for precise control of material parameters and critical dimensions of topology elements. An increase in the performance, functionality, and reliability of radio-photonic circuits is possible only when switching from discrete elements to integral. Construction of complex radio-photonic systems in the frequency range more than 30–40 GHz on the basis of discrete components becomes problematic and ineffective; therefore, the increase in the frequency range is typical for the FIS. For instance, a combination of the А3В5 / Si heterogeneous integration technology and the use of micro ring resonators as part of a PIS modulator recently allowed to create by developers record superlinear modulator with free dynamic range in the USA 117 dB · Hz2 / 3 [3]. FROM THE CENTER OF COMPETENCE TO CLUSTER One of the most important active elements of the radio-photonic component base is a microwave modulator. When using radio-photonic schemes with external modulation, the laser emits in a continuous mode, and the modulation of the signal is carried out by the modulator. This is currently the approach made it possible to achieve maximum modulation frequencies of 100 GHz and data transmission rates up to 400 Gbit / s. The development of a component base for radiophotonics has begun in Russia. For example, a modulator based on lithium niobate was developed at the Physicotechnical Institute (FTI) named after A.F. Ioffe RAS. However, until now, there was practically no groundwork in the country integrated radio-photonics technologies for formation of FIS. As a result, NRNU MEPhI became one of the leading centers of excellence for creation of a cluster for integrated radio photonics. It has great scientific and technical potential for research and developments in this extremely important area. Firstly, NRNU MEPhI has an experienced technological line for the development of electronic and optoelectronic devices for microwave electronics based on non-silicon heterostructures А3В5. Most of the processes on the creation of integrated radio photonics components on the InP technological platform.
You should understand what is modulation: Modulation is a technique to put the information of the message signal (at frequency A) to a carrier signal (at frequency B), this is often done to reduce interference or to reduce antenna size in case the message signal frequency is too low. In continuous waveform, this is done by adjusting the amplitude, phase or frequency off the carrier signal
type of modulation.PNG

modulated signal.PNG


31:52(english subtitles) there is an interesting bit on photonic radar operating in the Terra hertz frequency range.
He didn't mean the radar will transmit THz wave because the nature of Terra hertz is that it will get absorbed almost 100% immediately once it travel into atmosphere.
Water vapor in the atmosphere will absorb THz frequency at much much greater than they even absorb Infrared or visible light. You get attenuation rate of over 100dB-1000 dB per km. 100 dB is equal to 10.000.000.000 reduction in signal power. There is pretty good reason why THz frequency only used in the lab instead of any actual radar.
THz.PNG

To understand what he mean, you should understand how a radar work in the first place
coherent radar.PNG

In a coherent radar system, not only the amplitude but also the phase of the signal is considered to find range and velocity. Each cycle of magnetron oscillations starts with phase which is not related to the previous pulsed cycle, so RF oscillator is used to act as phase reference to find the phase of reflected signal.
In the transmit part, the oscillator generated a low frequency then this frequency go through the up-conversion process before being transmitted . Whereas, the receiver in a coherent radar working by frequency mixing with the local oscillator to convert a received signal to a lower intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency that it transmitted (the process of mixing two frequency is called heterodyning . ).Sometimes this conversion happen twice. The problem is that this up conversion, down conversion and mixing process is actually a main source of phase noise in radar; it adds the frequency fluctuations and hence leads to errors and in case of coherent radar the information is extracted from the change in the phase of the signal. So, in order to get good performance we need the phase of signal to be stable
In short, you need to get rid of the up/down conversion, so what they come up with, is using a mode locked laser to generate signal
MLL to generate signal.PNG

The signal from the laser is split into two separate paths, where two different modes are
selected by filters. One mode on one path is modulated to shape the radar pulse while the other mode on second path is frequency shifted. Frequency shift is required to get RF signal at required high frequency as we are using one MLL for transmitter and receiver at sampling rate. The two processed modes are then combined and detected in photodiode => There will be negligible increase of phase noise compared to original mode locked laser.
In the current radar, the way the receiver down convert the signal is by mixing it with the local oscillator. But this affect phase stability of the signal. With a photonic radar the signal is directly converted to digital form by the mode locked laser to be analyzed, there is no phase instability because the mode locked laser can provide a stable train of pulse with low jittering.
photonic mode locked.PNG

Basically what do he mean when he talk about the THz?. A microwave or mm-wave signal can be
generated in the optical domain based on optical heterodyning (I explained this earlier in case you forget), in which two optical waves of different wavelengths beat at a photodetector. An electrical beat
note is then generated at the output of the photodetector with a frequency corresponding to the
wavelength spacing of the two optical waves. This technique is capable of generating an electrical signal with a frequency up to the THz band, limited only by the bandwidth of the photodetector. But like I said before, generating an electrical signal at a certain frequency is one thing while transmitting it and use its in radar detection is an entirely different thing all together. The problem with THz is that it will get attenuated immediately by the atmosphere , whereas the problem with Hz band is that it basically turn your radar into an omi directional transmitter, so you can't really know where your target come from.
mode locked laser THZ.PNG




https://rg.ru/2018/04/08/revoliuciia-v-tehnike-lokacii-v-rossii-sozdaetsia-radiofotonnaia-rls.html "A team of specialists on the basis of the Research Institute of long-range radar is developing a fundamentally new X-band radar station, operating on the basis of radiophoton technologies

For example, the basis of radar systems for missile defense and tracking of space objects are huge radar systems. The rooms in which the equipment is located are multi-storey buildings. The use of photonic technology will fit all the control and processing systems in much smaller dimensions - literally in several rooms. At the same time, the technical capabilities of radars to detect even small objects at a distance of thousands of kilometers will only increase. Moreover, due to the use of photonic technologies on the radar screen will appear not a mark of the target, and its image, which is unattainable by classical radar. That is, the operator instead of the usual glowing point will see that it is really flying - a plane, a rocket, a flock of birds or a meteorite, it is worth repeating, even thousands of kilometers from the radar.

Now all radar systems - military and civilian - operate in a strictly defined range of frequencies, which complicates technical design and leads to a variety of radar range. Photon radars will achieve the highest degree of unification. They are able to instantly adjust in a very wide range of working frequencies - from meter values to millimeters."
Nope, no they don't , I'm pretty sure the writter of this click bait article doesn't even understand normal radar, let alone a photonic one.



TASS, January 4. The newest radar station "Yakhroma", the construction of which in Crimea was announced by the Minister of Defense of the Russian Federation Sergei Shoigu at the annual board of the Ministry of Defense, will operate in four ranges with a view of 270 degrees. A source in the military-industrial complex told TASS about it.

"This station has no analogues, it will operate in four bands: meter, centimeter, decimeter and millimeter," the agency's interlocutor said, specifying that the station's view would be 270 degrees
In December 2020, during the final collegium of the military department, Russian Defense Minister General of the Army Sergei Shoigu announced that the construction of the newest Yakhroma radar station in Sevastopol would begin in 2021.

The station will enter the missile attack warning system. The main purpose of the system is to detect and escort ballistic missiles fired at the territory of the Russian Federation or its allies as soon as possible.


.
You are confusing between a radar station and an individual radar. A station can easily have multiple type of radars, with vastly different aperture and radiating elements. So actually, it isn't surprise at all that it can operate at different frequencies




MOSCOW, January 22. /TASS/. The RTI Joint Stock Company, a developer and producer of high-tech products, will create new radars that operate in terahertz frequency range and are capable of pinpointing the smallest drone, RTI CEO Pavel Laptayev told TASS.

"The terahertz technology [featuring radio wave length below one millimeter] will be converted into a product within five years. These radars can detect small drones, and function in space," Laptayev explained.
Nope, as I have explained earlier, unless you can literally modify the earth atmosphere so that it no longer absorb THz wave, then no, you will not have a THz radar



I am 110% sure that I think I remember seeing your username browse the photonic radar thread when a user posted this source. https://fpi.gov.ru/press/news/razra...antenna-voshla-v-top-10-izobreteniy-2020-goda

An antenna of low profile height, capable of operating with a wide frequency band, developed within the framework of a project of the Foundation for Advanced Study, was included in the Top 10 of the best inventions of 2020 according to Rospatent.

On the basis of the invention, dummies of antennas were created, an antenna array of the first in the world practice of a working demonstration model of a radio-optical phased active antenna array was built. The technology makes it possible to create antennas and antenna arrays, which can be made in the form of active casing of various carriers with a thickness slightly more than the thickness of the paint-and-lacquer coating.

The main executor of the project is Concern Vega JSC, the head enterprise of the intelligence information systems division of the Ruselectronics holding company of the Rostec State Corporation, specializing in the development and production of an extensive range of modern radio-electronic products and systems for military and civil purposes. The concern's management includes more than 20 organizations. The author of the invention is Dmitry Zaitsev, Deputy General Designer for Radiophotonics of JSC Concern Vega.

I think yours and another users complaint is frequencies like VHF and UHF need huger antennas. Well the antennas of the photonic radar they demonstrated look stackable and in terms of thickness will have no issues spreading all over the body of an aircraft. Oh well but the fun does not stop there.
:pound: I think you miss understand the point when I said UHF, VHF need huge antenna.
Firstly, you don't need huge antenna to simply transmit VHF or UHF wave, you can transmit these wave with small antenna. The problem is that, if you want to make a useful radar, then the gain (directivity) of that radar must be adequate, in short, the beamwidth must be narrow. An to get a narrow beam width at low frequency, you Must have a big antenna, otherwise, your beamwidth would be omi direction or simply too wide, which make your so called "radar" useless
Secondly, they can even put a VHF antenna on the vertical tail fin of F-18 and F-35, and patch antenna generally can be very thin.
VHF antenna on F-35.PNG


But the problem with your proposed Photonic radar which according to internet tabloid "can work in the frequency range from Hz to Thz" is not the thickness of the antenna, the problem is with the spacing between the radiating elements because electronic scanned array steer their beam by wave interference. In short, you can make the radiating elements very thin, but the big issue is the spacing between them on the surface they are on, even if you can make the individual element as thin as paper, it still doesn't solve the problem that I mentioned at all.
 

StealthFlanker

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https://www.militaryaerospace.com/rf-analog/article/14178607/rf-and-microwave-photonics-radar
Industry asked to develop microwave photonics components for RF and microwave applications like radar
DARPA wants lithium-niobate field-configurable modulator arrays (FCMAs) for RF links, RF signal processing, radar, and RF spectrum management.

Although microwave photonics represents an important technology for military applications, the military microwave photonic systems deployed to date repurpose commercial components for military functions.

The most recent developments in industrial telecommunications have been in specialized application-specific photonic integrated circuits (PICs). Today's military applications cannot use these devices, however, because application-specific PICs cannot be repurposed.

The FCMA must be able to operate from 1 MHz to 18 GHz,
and use the nonlinear response of a Mach-Zehnder modulator to suppress a continuous-wave interference signal by 60 decibels to suppress an interference signal with 10 MHz instantaneous bandwidth by 40 decibels -- both while reducing the largest intermodulation distortion by 30 decibels.

The signals-intelligence configuration will improve the intrinsic third-order-limited spurious-free dynamic range of a Mach-Zehnder modulator by 10 decibels.

The radar-beamforming application will provide 360 degrees of RF phase shift that can be modulated at 100 kHz. The communications configuration, meanwhile, must support 10 gigabits per second of modulation on each of the in-phase and quadrature components of a lightwave.

https://www.raytheon.com/sites/defa...9/05/Raytheon_TechnologyToday_Issue2_2019.pdf "With all the advances occurring in
emerging PIC technologies, Raytheon
researchers and engineers are actively
pursuing both internal research and
customer-funded development programs
to investigate applications of PIC
technology in next generation products,
as well as to develop lower cost, higher
yield PIC packaging and manufacturing
processes"

https://itech.aorti.ru/ No. 1 (20) of 2018 As for semiconductor
modulators in microchip
performance, then in 2019 the research
work on this topic in which
OKB-Planeta OJSC is an industrial partner.
Within three to five years is possible
organization of the development, design and production of photonic
integrated circuits (FIS) both in packageless execution, and in the case.

The implementation of these plans will allow
JSC "RTI" take a leading position
in development and production
advanced domestic radio systems based on component
radiophotonic bases.


I dont think there is anymore denying that PICs are the next step after MMICs. Also I found something more interesting in regards to photonics but by Raytheon. Raytheon_TechnologyToday_Issue2_2019.pdf pg 44 or pg 24 in PDF.
I pretty much already explained this in my post about photonic radar above, so you can look up.


2D materials enable novel electronics and sensor technologies not previously possible. A recent joint study led by Raytheon BBN and Harvard University indicates that 2D electrons flow like a fluid rather than like a gas.2 This discovery describes a new electrical transport regime in which the interactions among the electrons are much stronger than those between the electrons and the impurities inside the materials. The Raytheon team, in collaboration with MIT and Harvard University, is now using this electron fluid concept to develop electronics with lower power consumption as well as a new ultrawide bandwidth amplifier enabled by steering the electron fluid. The amplifier design is analogous to modulating the direction of a jet stream, achieving wide-bandwidth amplification to more than 100 gigahertz (GHz). Graphene is the first material in the entire 2D material family to be exfoliated down to mono-atomic layer thickness, opening up a new area of nanotechnology. In addition to its outstanding mechanical properties and thermal conductivity, graphene possesses some remarkable properties based on its electron behaviors. The electrons can move as massless particles and follow relativistic dynamics rather than Newtonian dynamics. This departure from conventional conductors gives rise to new fundamental physics in graphene, such as high electronic mobility, wide bandwidth electromagnetic wave absorption, and fast thermal response. These properties translate to innovations in ultrafast infrared sensing and single-photon detection. Raytheon BBN is a prominent player in the research and development of these new nanotechnologies with recent publications in the Physical Review Applied and Nature Nanotechnology scientific journals.3,4 The graphene-based singlephoton detector (Figure 1), for example, shows a sensitivity approximately 10,000 times higher than current state-of-the-art detectors, and promises to enable novel solutions and products in sensing, imaging, and communication applications for Raytheon in years to come.

Another source stated 100,000 times more sensitivity. something on a related note above. Russian researchers explore the prospects for creating photonic integrated circuits (phys.org)
The transition from electronic integrated circuits to faster, more energy-efficient and interference-free optical circuits is one of the most important goals in the development of photon technologies. Photonic integrated circuits (PICs) are already used today for transmitting and processing signals in optical networks and communication systems, including, for example, I/O multiplexers of optical signals and microchips with an integrated semiconductor laser, a modulator and a light amplifier. However, today PICs are mostly used in combination with electronic circuits, while purely photonic devices are not yet competitive.

One of the challenges in creating PICs is the complexity of manufacturing various devices (waveguide couplers, power dividers, amplifiers, modulators, lasers and detectors on a single microchip), since they require different materials. The main materials used in existing PICs are semiconductors (indium phosphate, gallium arsenide, silicon), electro-optical crystals (lithium niobate), as well as various types of glass.

In order to increase the speed of PICs in controlling light flux, researchers are searching for new materials with high optical nonlinearity. Among promising materials, one can name, in particular, microwaveguides based on the newly discovered material, graphene (a layer of carbon atoms one atom thick), in which charge carrier concentrations can be effectively controlled using optical pumping or applied bias voltage.

According to Mikhail Bakunov, head of the UNN General Physics Department, recent theoretical and experimental work shows the possibility of superfast (involving times of several light field periods) carrier concentration changes in graphene, which opens up possibilities for manip
ulating the amplitude and frequency of light waves (plasmons) directed by the graphene surface.


if RTI, KRET and Vega are not that convincing than maybe Raytheon is. they stated that a several story ground radar is as efficient as a photonic radar on a kamaz truck. Than I am hearing photodetectors giving them 10,000 times more sensitivity.
Firstly, I already explained how a mode locked laser is used in photonic radar to avoid phase noise due to up conversion process
Secondly, I don't see how the sensitivity of photodetector have anything to do with radar? what you are trying to imply?. Photonic radar doesn't actually transmit light to target, just so you know.


Are they correct about 40 - 60 dB for threshold sensitivity and that EW systems can only make a jamming signal of 70-80? What kind of jamming are they talking about?
They are talking about noise jamming.
also, dB is a ratio unit, meaning it is often used to show a ratio, in this case the dB unit is used to show the J/S ratio aka the jamming/signal ratio. To increase this ratio, you can either increase the jamming power: by getting more powerful jammer, get the jammer closer to radar. Or reduce the reflected signal: by getting the aircraft further from the radar, or reduce RCS of aircraft (for example from F-15 to F-35 the signal reduced by 40 dB)

oh no its over bros

1618708373422.png

Российский фотонный радар подпишет приговор стелс-самолетам США - ИАНЕД (ianed.ru)
Scientists and designers of the Vega concern have successfully completed the first test of the mock-demonstrator of the active phased antenna of the radar grille, acting on the principles of radiophotonics (ROFAR).
This was announced by its CEO Vyacheslav Mikheev at the "Army-2020" international forum held in The Kubinka, Moscow.
Commenting on his statement, MK emphasizes that such devices can be used to make radars of much smaller sizes, which, nevertheless, will be able to see targets at many times more distance than usual.
But, most importantly, for ROFAROV do not matter the use of the notorious stealth technology on aircraft, which are the main bet in the U.S. Air Force. They are considered to be the main advantage of the very expensive (price above $100 million) American F-35 and F-22 fighter jets, which the Pentagon calls the 5th generation aircraft.
According to the unanimous opinion of military observers, the production of radar with the ROFAR system will impose the death sentence on all stealth technologies.
Well, this is not the first time I heard that phrase: "stealth dead" or "stealth is useless"
First with the magical plasma stealth, then with the magical IRST, then with the magical AESA radar, then with the magical low frequency radar, then with the magical passive radar...etc. The list go on and on. But guess what, all the super power still making stealth aircraft, plenty of them in fact. So either that they are all morons or these click bait authors are. I know which one I believe.
 

StealthFlanker

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Problem with drawing out any equations to communicate on RADARS and other military studies is that their validity is in absolute domains like in vaccum or at absolute pressures and so on with other physics related stuff. Like 1G ethernet at 1000 Mbps but in effect we all know ethernet goes at 70% throughput (or used to) and Wifi even less.....quoting equations might get you off on feeling good but real world studies are covered under secrecy by respective countries. U-2 was shot down...a real world example. Myth busters proved dropping a penny in theory from Empire state building should kill someone if it lands on them....almost supersonic speed but in reality air resistence and friction make it unlikely to the other end of probability. Uninteresting way if you try to quote equations on these sort of things without some empirical experiments..
Firstly, these equation don't just work in absolute vacuum, these equation are created so that operator and mission planner can calculate at which range the jamming lose effectiveness and also help the designer estimate the jamming output required for their system. It is pretty much the fundamental of EW warfare just like how EM diagram is fundamental to BFM. It is quite different from your ethernet example which is simply advertising.
Secondly atmosphere attenuation of frequency which fighter and ground radar operate at is very low, and the attenuation is uniform on both transmit and receive so the ratio is the same with or without atmospheric attenuation is taken into account.
Thirdly, I'm not sure what you are trying to prove with the U-2 example?, the S-75 engagement envelop excess the service ceiling of U-2, therefore it can be shootdown. Nothing unusual about that

Best evidence is real world use and not just claims.....fact is US had a lead of 20 years over everyone else in 5th gen domain and yet they are struggling and no real world use of this plane against even 2nd rated powers.
What sort of real world use would you want?
When was the last time P-700 or Brahmos was used in real combat?
When was the last time Kirov was used in real combat ?
When was the last time Rafale or Typhoon shotdown a fighter jet?
When was the last time S-400 shotdown a 5 generation fighter?
...etc
I can go on and on but I think you got the point.
 

omaebakabaka

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Firstly, these equation don't just work in absolute vacuum, these equation are created so that operator and mission planner can calculate at which range the jamming lose effectiveness and also help the designer estimate the jamming output required for their system. It is pretty much the fundamental of EW warfare just like how EM diagram is fundamental to BFM. It is quite different from your ethernet example which is simply advertising.
Secondly atmosphere attenuation of frequency which fighter and ground radar operate at is very low, and the attenuation is uniform on both transmit and receive so the ratio is the same with or without atmospheric attenuation is taken into account.
Thirdly, I'm not sure what you are trying to prove with the U-2 example?, the S-75 engagement envelop excess the service ceiling of U-2, therefore it can be shootdown. Nothing unusual about that


What sort of real world use would you want?
When was the last time P-700 or Brahmos was used in real combat?
When was the last time Kirov was used in real combat ?
When was the last time Rafale or Typhoon shotdown a fighter jet?
When was the last time S-400 shotdown a 5 generation fighter?
...etc
I can go on and on but I think you got the point.
Equations don't really turn into physical reality as they are qualified under ideal conditions or statistical context or some other factors that are constrained. Tossing a coin 10 times does not gurantee p at 0.5....its just likely as number of trials goes up. All relevant studies that deal with real world combat related parameters including radar abilities are classified for decades and operate under a set of conditions. Same goes with stealth...its a claim but to what degree needs some convincing evidence, anyone working in signal related electronics and analysis know the importance of real world losses and unknowns vs equations in theory and some losses are explainable but some can't be determined but that doesn't mean its impossible to determine. Btw, I am not denying your theories but I am just saying there is lot of abilities in cryptography, DSP that are still top secret including new physical principles. So common sense says be conservative when it comes to this wonder weapon till it gains some stars and stripes vs real enemy as there is lot of overclaims on it.

U-2 was assumed to be unreacheable at the time but they got a black eye. There are no outrageous claims regarding the other things.....F-35 stealth is overhyped and all overclaimed things are half believable till evidence comes out.....same with s-400 and other examples you pointed.

For x phone, its 3 day battery life blah blah but then there is fine print.
 
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StealthFlanker

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Equations don't really turn into physical reality as they are qualified under ideal conditions or statistical context or some other factors that are constrained. Tossing a coin 10 times does not gurantee p at 0.5....its just likely as number of trials goes up. All relevant studies that deal with real world combat related parameters including radar abilities are classified for decades and operate under a set of conditions. Same goes with stealth...its a claim but to what degree needs some convincing evidence, anyone working in signal related electronics and analysis know the importance of real world losses and unknowns vs equations in theory and some losses are explainable but some can't be determined but that doesn't mean its impossible to determine. Btw, I am not denying your theories but I am just saying there is lot of abilities in cryptography, DSP that are still top secret including new physical principles. So common sense says be conservative when it comes to this wonder weapon till it gains some stars and stripes vs real enemy as there is lot of overclaims on it.
You are confusing between actual parameters of weapon systems, which can be classified and the physic of weapon system which can't be classified because it is physics. You can make something like the minimum detectable signal and the gain of a radar a classified value, but how the wave propagate through air, how the reduction in RCS will affect J/S is just physics, you can't either change or make them classified information. Tossing a coin isn't the same as calculating radar parameter, because tossing the coin is a probability based action when you have very little available information whereas calculating radar performance based on a given parameter is somewhat similar to calculating if a car driving at 50 km/h on a straight line from point A to B, how long does it take to reach B if the two point are 200 km apart. It is very straight forward, if you know the parameter, you can calculate, simple as that.


U-2 was assumed to be unreacheable at the time but they got a black eye. There are no outrageous claims regarding the other things.....F-35 stealth is overhyped and all overclaimed things are half believable till evidence comes out.....same with s-400 and other examples you pointed.
For x phone, its 3 day battery life blah blah but then there is fine print.
U-2 was assumed to be unreachable by the aircraft at that time, which it is. It is not unreachable to S-75 which is a huge rocket.
Secondly, "outrageous claims" is a matter of perspective, pretty much every single things in my list can be said to have many overhyped claim related to them, F-35 isn't an exception.
 

panzerfeist1

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He didn't mean the radar will transmit THz wave because the nature of Terra hertz is that it will get absorbed almost 100% immediately once it travel into atmosphere.
Water vapor in the atmosphere will absorb THz frequency at much much greater than they even absorb Infrared or visible light. You get attenuation rate of over 100dB-1000 dB per km. 100 dB is equal to 10.000.000.000 reduction in signal power. There is pretty good reason why THz frequency only used in the lab instead of any actual radar.
THz.PNG

To understand what he mean, you should understand how a radar work in the first place
coherent radar.PNG

In a coherent radar system, not only the amplitude but also the phase of the signal is considered to find range and velocity. Each cycle of magnetron oscillations starts with phase which is not related to the previous pulsed cycle, so RF oscillator is used to act as phase reference to find the phase of reflected signal.
In the transmit part, the oscillator generated a low frequency then this frequency go through the up-conversion process before being transmitted . Whereas, the receiver in a coherent radar working by frequency mixing with the local oscillator to convert a received signal to a lower intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency that it transmitted (the process of mixing two frequency is called heterodyning . ).Sometimes this conversion happen twice. The problem is that this up conversion, down conversion and mixing process is actually a main source of phase noise in radar; it adds the frequency fluctuations and hence leads to errors and in case of coherent radar the information is extracted from the change in the phase of the signal. So, in order to get good performance we need the phase of signal to be stable
In short, you need to get rid of the up/down conversion, so what they come up with, is using a mode locked laser to generate signal
MLL to generate signal.PNG

The signal from the laser is split into two separate paths, where two different modes are
selected by filters. One mode on one path is modulated to shape the radar pulse while the other mode on second path is frequency shifted. Frequency shift is required to get RF signal at required high frequency as we are using one MLL for transmitter and receiver at sampling rate. The two processed modes are then combined and detected in photodiode => There will be negligible increase of phase noise compared to original mode locked laser.
In the current radar, the way the receiver down convert the signal is by mixing it with the local oscillator. But this affect phase stability of the signal. With a photonic radar the signal is directly converted to digital form by the mode locked laser to be analyzed, there is no phase instability because the mode locked laser can provide a stable train of pulse with low jittering.
that is irrelevant to photonics but relevant to MMICs great job as usual. The designer general of EWS made it clear Thz is going to be used, you see this is the reason why I decided to do a bunch of news dumps here. https://itech.aorti.ru/upload/iblock/d00/RTI_2_2017.pdf page 69 "Terahertz radar stations
can not only improve the accuracy of determining the coordinates and parameters of air
objects, but also to identify their type.
Small size and weight of the antenna
and devices of the terahertz range make it possible to create portable stations operating in conditions of smoke and atmospheric precipitation. Mass production
Radar of a new generation, according to the director
scientific and technical center "Terahertsy"
OJSC "RTI" by Alexey Vagin, may start
over the next 5 years. And in the structure
Concern "RTI" has enterprises that
able to master the serial production of such
devices based on the THz range: for example,
Yaroslavl Radio Plant.
In general, the comprehensive development of the THz-range is one of the key tasks of the scientific world.
It is gratifying that Russian scientists are making their own
a significant contribution to its solution. "


Not trying to be funny here but like you they complained about the radiation be absorbed by the atmosphere paragraphs prior to this one, hell 100ghz or above frequencies suffer atmosphere attenuation but yet RTI KRET and other companies. Also it does not have to be 1hz they gave multiple references in the meter to millimeter just in case you still sound hung up about 1hz.

Nope, no they don't , I'm pretty sure the writter of this click bait article doesn't even understand normal radar, let alone a photonic one.
So DARPA stating lithium-niobate field-configurable modulator arrays (FCMAs) which are being funded for next gen radars in the microwave photonics field of 1mhz to 18ghz source is no better either? Oh shit, is DARPA owned by Russia?

You are confusing between a radar station and an individual radar. A station can easily have multiple type of radars, with vastly different aperture and radiating elements. So actually, it isn't surprise at all that it can operate at different frequencies
hmm they said meter to millimeter values, gave a radar of that but millimeter works in the 30-300ghz range. I am going to pretend with you that they are indeed working on 4 different radar stations. has the U.S. or any other country fielded a ground radar in the 30-300ghz range? is the FCMA also 4 seperate radars? What about Mikheeyev stating photonic radar uses UHF signals and also stating 100ghz? Are those also 4 seperate radars?
Nope, as I have explained earlier, unless you can literally modify the earth atmosphere so that it no longer absorb THz wave, then no, you will not have a THz radar
OK you disagree with RTI and designer general of the EWS on this field because they do not want to disclose this information out to the public. https://www.aorti.ru/media/news/rti-vpervye-pokazhet-demonstratsionnyy-obrazets-kompleksa-dosmotr-/ Currently cannot find youtube video where they demonstrate a 10 meter corridor of people and walking through airports and only getting called out if weapons are found. Do other airports have demonstrated this? I just want to get a good feel on where other countries stand in thz sensing technology.

I think you miss understand the point when I said UHF, VHF need huge antenna.
Firstly, you don't need huge antenna to simply transmit VHF or UHF wave, you can transmit these wave with small antenna. The problem is that, if you want to make a useful radar, then the gain (directivity) of that radar must be adequate, in short, the beamwidth must be narrow. An to get a narrow beam width at low frequency, you Must have a big antenna, otherwise, your beamwidth would be omi direction or simply too wide, which make your so called "radar" useless
Secondly, they can even put a VHF antenna on the vertical tail fin of F-18 and F-35, and patch antenna generally can be very thin.
I remember Abhirup Sengupta(if kim lee ryo is your only quora account) mentioning something like this I am wondering if I am talking to him right this minute because you seem more active at indai defense net
than other forums, than again I have second thoughts on that because you have Vietnamese origins and Vietnam is the most pro-american country(bet full metal jacket isnt your favorite movie) with Israel behind(Guess I see why you like some Israeli weapons) and I remember you browsing to poland related rockets or some shit at secret projects which is the 5th most pro-american country. But I remember he dodged my question which I wonder if you would do the same now. If the FMCA beamwidth is too wide can it be narrowed to the specific frequencies it needs like instead of 1mhz to 18ghz can it just be 8-10ghz? VHF antennas of MMIC technology probably wont fit because of size. Do they have VHF antennas as thick as paper?

I pretty much already explained this in my post about photonic radar above, so you can look up.
Are you not feeling a little nervous that different Russian companies along with U.S. companies say the same shit about the compatibility of using higher than fire control frequencies? Hell the BAE Tempest claims its radar can get the amount of information as a city in Edinburgh per second. It seems that alot of different sources tell me that photonic communication can hit 100s of gigabit to terabits in exchanging information per second and I probably don't have to tell you twice that frequencies higher than MADL can do this. Overall the likelihood is even possible the Tempest can use a photonic radar, but I am not drawing that conclusion just yet.

They are talking about noise jamming.
also, dB is a ratio unit, meaning it is often used to show a ratio, in this case the dB unit is used to show the J/S ratio aka the jamming/signal ratio. To increase this ratio, you can either increase the jamming power: by getting more powerful jammer, get the jammer closer to radar. Or reduce the reflected signal: by getting the aircraft further from the radar, or reduce RCS of aircraft (for example from F-15 to F-35 the signal reduced by 40 dB)
So to put it correctly.
1618796981801.png

The photonic crystal with its line would be at 200 on this chart? I know you are the kind of guy that has alot of charts am I using the right one?

Well, this is not the first time I heard that phrase: "stealth dead" or "stealth is useless"
First with the magical plasma stealth, then with the magical IRST, then with the magical AESA radar, then with the magical low frequency radar, then with the magical passive radar...etc. The list go on and on. But guess what, all the super power still making stealth aircraft, plenty of them in fact. So either that they are all morons or these click bait authors are. I know which one I believe.
Are there any stealth aircrafts that can deal with 100ghz or terahertz radiation? KRET deleted their own website before with information of frequency and that a several story ground radar would work as efficient as a kamaz truck mounted photonic radar. And the general designer doesnt want to talk to go into any further detail. This could be a great strategical asset once the U.S. continues dumping more into the F-35 program for its reliance all the way to 2070. Than they start producing next generation PIC radars for air defenses and aircrafts. VEGA, RTI, KRET and general designer of ABM shield made it more than clear of the frequencies they are working with. If I was an adversary nation to the U.S. I to would want them to spend money like idiots until I make them realize later that 5th gens can turn into 4th gens. stealth is important only to keep the X-band users far enough to not give them a chance to fire missiles until they do.
 

omaebakabaka

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You are confusing between actual parameters of weapon systems, which can be classified and the physic of weapon system which can't be classified because it is physics. You can make something like the minimum detectable signal and the gain of a radar a classified value, but how the wave propagate through air, how the reduction in RCS will affect J/S is just physics, you can't either change or make them classified information. Tossing a coin isn't the same as calculating radar parameter, because tossing the coin is a probability based action when you have very little available information whereas calculating radar performance based on a given parameter is somewhat similar to calculating if a car driving at 50 km/h on a straight line from point A to B, how long does it take to reach B if the two point are 200 km apart. It is very straight forward, if you know the parameter, you can calculate, simple as that.



U-2 was assumed to be unreachable by the aircraft at that time, which it is. It is not unreachable to S-75 which is a huge rocket.
Secondly, "outrageous claims" is a matter of perspective, pretty much every single things in my list can be said to have many overhyped claim related to them, F-35 isn't an exception.
Calculation time it takes to go from A to B is as you say but maintaining that speed is the practical aspect of it that is dependant on various physical conditions. Stealth is something like that....physics is one side of it that holds true under set conditions. Propagation of wave in practice is impacted by many things known and new methods come all the time especially with big data now. Even s-400 is overclaimed and I hold it to same constraint, it has not been proven to be as effective as it is claimed yet. Does not mean it is or isn't....verification is the last step to a claim. Until then its just that claim. For instance the paint, if someone can come up with a paint to absorb then someone else can come up with a way to neutralize it....its pretty realistic hypothesis.
 

StealthFlanker

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that is irrelevant to photonics but relevant to MMICs great job as usual.
What I just explained to you in earlier post, is the fundermental of photonic radar, and why they are developed and how they worked.

The designer general of EWS made it clear Thz is going to be used, you see this is the reason why I decided to do a bunch of news dumps here. https://itech.aorti.ru/upload/iblock/d00/RTI_2_2017.pdf page 69 "Terahertz radar stations
can not only improve the accuracy of determining the coordinates and parameters of air
objects, but also to identify their type.
Small size and weight of the antenna
and devices of the terahertz range make it possible to create portable stations operating in conditions of smoke and atmospheric precipitation. Mass production
Radar of a new generation, according to the director
scientific and technical center "Terahertsy"
OJSC "RTI" by Alexey Vagin, may start
over the next 5 years. And in the structure
Concern "RTI" has enterprises that
able to master the serial production of such
devices based on the THz range: for example,
Yaroslavl Radio Plant.
In general, the comprehensive development of the THz-range is one of the key tasks of the scientific world.
It is gratifying that Russian scientists are making their own
a significant contribution to its solution. "


Not trying to be funny here but like you they complained about the radiation be absorbed by the atmosphere paragraphs prior to this one, hell 100ghz or above frequencies suffer atmosphere attenuation but yet RTI KRET and other companies. Also it does not have to be 1hz they gave multiple references in the meter to millimeter just in case you still sound hung up about 1hz.
So DARPA stating lithium-niobate field-configurable modulator arrays (FCMAs) which are being funded for next gen radars in the microwave photonics field of 1mhz to 18ghz source is no better either? Oh shit, is DARPA owned by Russia?
hmm they said meter to millimeter values, gave a radar of that but millimeter works in the 30-300ghz range.

As I told you earlier, the THz is the value of maximum frequency of electric beat which can be created by the twin laser hitting a photodiode. Because the maximum value is extremely high, that mean you don't need the up conversion when you transmit normal frequency.That mean you can reduce the phase nose. It doesn't actually mean the radar will transmit THz wave.
At most, THz wave are used in labs, to examine surface of something with very high resolution, but it is pretty much useless for radar application




I am going to pretend with you that they are indeed working on 4 different radar stations. has the U.S. or any other country fielded a ground radar in the 30-300ghz range?
It is absolutely normal that a station have several radars at different frequency at the sametime, even on a ship you can see they put multiple type of radar on it for different function. A station is many times bigger than a ship and often look somewhat like this
1.jpg

Millimeter wave radar are not very popular due to absorption rate of the atmosphere, but you can find them on missile seeker such as Brimstone, Aster ..etc

the FCMA also 4 seperate radars? What about Mikheeyev stating photonic radar uses UHF signals and also stating 100ghz? Are those also 4 seperate radars?Are you not feeling a little nervous that different Russian companies along with U.S. companies say the same shit about the compatibility of using higher than fire control frequencies?
When you read about photonic radar and the range of frequency that they operate at. These aren't actually the frequency that the radar will transmit. It is the frequency range that can be generated by the mode locked laser inside the radar itself.
mode locked laser THZ.PNG

Basically, you can generate very high or very low frequency by the optical modulator so there is no up or down conversion, so there is very low phase nose. But it doesn't actually mean the radar will operate in that whole 1Hz-1THz range



OK you disagree with RTI and designer general of the EWS on this field because they do not want to disclose this information out to the public. https://www.aorti.ru/media/news/rti-vpervye-pokazhet-demonstratsionnyy-obrazets-kompleksa-dosmotr-/ Currently cannot find youtube video where they demonstrate a 10 meter corridor of people and walking through airports and only getting called out if weapons are found. Do other airports have demonstrated this? I just want to get a good feel on where other countries stand in thz sensing technology.
I don't know what you think so awesome about this?. This is used at airport security even now.
They have a little door that you go through, if you have a metal weapons then the door will make a ring. It is pretty much the same thing. The distance is only a few meters and inside a confine space where moisture can be removed easily. It is completely different from using THz in radar application where targets are ten to hundreds kilometers away.

I remember Abhirup Sengupta(if kim lee ryo is your only quora account) mentioning something like this I am wondering if I am talking to him right this minute because you seem more active at indai defense net
than other forums, than again I have second thoughts on that because you have Vietnamese origins and Vietnam is the most pro-american country(bet full metal jacket isnt your favorite movie) with Israel behind(Guess I see why you like some Israeli weapons) and I remember you browsing to poland related rockets or some shit at secret projects which is the 5th most pro-american country. But I remember he dodged my question which I wonder if you would do the same now. If the FMCA beamwidth is too wide can it be narrowed to the specific frequencies it needs like instead of 1mhz to 18ghz can it just be 8-10ghz? VHF antennas of MMIC technology probably wont fit because of size. Do they have VHF antennas as thick as paper?
Firstly, no, I'm not Abhirup Sengupta , you should stop thinking that everyone ever disagree with you is the same person or that there are some dark plan to get you. Furthermore, Viet Nam also not the most pro american country, if anything, Vietnam and USA did have pretty much massive war in the past.
Secondly, there isn't any issue with using a narrow down to a specific frequency such as 8-10ghz, as a matter of fact, that how it will operate, you will not have a radar which operate in the range from1 Hz-1 THz, because again, element spacing is a big issue.


Hell the BAE Tempest claims its radar can get the amount of information as a city in Edinburgh per second. It seems that alot of different sources tell me that photonic communication can hit 100s of gigabit to terabits in exchanging information per second and I probably don't have to tell you twice that frequencies higher than MADL can do this. Overall the likelihood is even possible the Tempest can use a photonic radar, but I am not drawing that conclusion just yet.
Tempest new radar is a digital beam forming radar if I recall correctly. The main advantage is in the quantity of null that it can created compared to analog beam forming radar
Digital beam forming.jpg



So to put it correctly.
View attachment 85868
The photonic crystal with its line would be at 200 on this chart? I know you are the kind of guy that has alot of charts am I using the right one?
your article talking about dynamic range of receiver, so it should be this chart
dynamic range.PNG


The bottom level of the range is governed by its sensitivity whilst the top end it is governed by its overload or strong signal handling performance. That said there are several different conventions that are used for measuring the receiver dynamic range.

Are there any stealth aircrafts that can deal with 100ghz or terahertz radiation? KRET deleted their own website before with information of frequency and that a several story ground radar would work as efficient as a kamaz truck mounted photonic radar. And the general designer doesnt want to talk to go into any further detail. This could be a great strategical asset once the U.S. continues dumping more into the F-35 program for its reliance all the way to 2070. Than they start producing next generation PIC radars for air defenses and aircrafts. VEGA, RTI, KRET and general designer of ABM shield made it more than clear of the frequencies they are working with. If I was an adversary nation to the U.S. I to would want them to spend money like idiots until I make them realize later that 5th gens can turn into 4th gens. stealth is important only to keep the X-band users far enough to not give them a chance to fire missiles until they do.
All stealth aircraft can easily deal with 100 Ghz and THz radiation
Firstly, because the wave at these frequency will get attenuated significantly before they even have the chance to reach the aircraft
Secondly, because the frequency is very high, the wavelength is very small compared to the size of the aircraft, which mean all the reflection will fall into optical region rule of reflection and the return will be specular return which is the kind of return most easy to deal with on stealth aircraft.
 

panzerfeist1

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All stealth aircraft can easily deal with 100 Ghz and THz radiation
Firstly, because the wave at these frequency will get attenuated significantly before they even have the chance to reach the aircraft
Secondly, because the frequency is very high, the wavelength is very small compared to the size of the aircraft, which mean all the reflection will fall into optical region rule of reflection and the return will be specular return which is the kind of return most easy to deal with on stealth aircraft.
I am not for or against on your opinions of radars being unable to work in those conditions because I am no subject matter expert in the field of photonics. Its just a hunch on why is the U.S. military asking for a F-16 replacement along with producing F-15s again. This is just sort of a I let you know that they have different companies like VEGA, RTI, KRET and even the general designer of the EWR stating such frequency ranges. I mean its very odd that no country before has bothered or made radars for military use with 100ghz or above but of course there is an emergence of news sources left and right that they will be used for military purposes. I will get back to you on this subject again once they give performance specs on the Yakhroma radar's range performance using 30-300ghz waves since its construction is to start somewhere this year.

Закроет два моря и весь юг Европы: В Крыму появится уникальная РЛС «Яхрома» » Актуальные новости (actualnews.org)

"Thanks to such technical features, Shoigu noted, the Russian military on the peninsula will be able to track the presence and movement of all targets that are several thousand kilometers away, including stealth aircraft, UAVs, ballistic and cruise missiles. newest radar, the construction of which was announced within the framework of the annual board of the Ministry of Defense, the head of the Ministry of Defense Sergei Shoigu, will be deployed in Crimea and will start working in four wave ranges at once," TASS reports, citing its own sources in the domestic defense industry."

Not enough info of characteristics performance, but this came out of Shoigus mouth.
 

BON PLAN

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What I just explained to you in earlier post, is the fundermental of photonic radar, and why they are developed and how they worked.


As I told you earlier, the THz is the value of maximum frequency of electric beat which can be created by the twin laser hitting a photodiode. Because the maximum value is extremely high, that mean you don't need the up conversion when you transmit normal frequency.That mean you can reduce the phase nose. It doesn't actually mean the radar will transmit THz wave.
At most, THz wave are used in labs, to examine surface of something with very high resolution, but it is pretty much useless for radar application





It is absolutely normal that a station have several radars at different frequency at the sametime, even on a ship you can see they put multiple type of radar on it for different function. A station is many times bigger than a ship and often look somewhat like this
View attachment 85875
Millimeter wave radar are not very popular due to absorption rate of the atmosphere, but you can find them on missile seeker such as Brimstone, Aster ..etc


When you read about photonic radar and the range of frequency that they operate at. These aren't actually the frequency that the radar will transmit. It is the frequency range that can be generated by the mode locked laser inside the radar itself.
View attachment 85877
Basically, you can generate very high or very low frequency by the optical modulator so there is no up or down conversion, so there is very low phase nose. But it doesn't actually mean the radar will operate in that whole 1Hz-1THz range




I don't know what you think so awesome about this?. This is used at airport security even now.
They have a little door that you go through, if you have a metal weapons then the door will make a ring. It is pretty much the same thing. The distance is only a few meters and inside a confine space where moisture can be removed easily. It is completely different from using THz in radar application where targets are ten to hundreds kilometers away.


Firstly, no, I'm not Abhirup Sengupta , you should stop thinking that everyone ever disagree with you is the same person or that there are some dark plan to get you. Furthermore, Viet Nam also not the most pro american country, if anything, Vietnam and USA did have pretty much massive war in the past.
Secondly, there isn't any issue with using a narrow down to a specific frequency such as 8-10ghz, as a matter of fact, that how it will operate, you will not have a radar which operate in the range from1 Hz-1 THz, because again, element spacing is a big issue.



Tempest new radar is a digital beam forming radar if I recall correctly. The main advantage is in the quantity of null that it can created compared to analog beam forming radar
View attachment 85881



your article talking about dynamic range of receiver, so it should be this chart
View attachment 85883

The bottom level of the range is governed by its sensitivity whilst the top end it is governed by its overload or strong signal handling performance. That said there are several different conventions that are used for measuring the receiver dynamic range.


All stealth aircraft can easily deal with 100 Ghz and THz radiation
Firstly, because the wave at these frequency will get attenuated significantly before they even have the chance to reach the aircraft
Secondly, because the frequency is very high, the wavelength is very small compared to the size of the aircraft, which mean all the reflection will fall into optical region rule of reflection and the return will be specular return which is the kind of return most easy to deal with on stealth aircraft.
The main tool to break fighter stealth is low wave frequency.
It is why the chinese new frigates and destroyers are fitted with low band radars. and so one...
 

FalconSlayers

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The main tool to break fighter stealth is low wave frequency.
It is why the chinese new frigates and destroyers are fitted with low band radars. and so one...
But it doesn’t a good resolution of the target to direct fire, that is why it can’t be used as a fire control radar only good for detection. Has its own advantages as enhanced situational awareness, but fact will remain that due to low RCS it will be difficult for X-band fire control radars to direct fire at the tango unless it gets too close and by then the tango would break you apart.
 

SARTHAK

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The main tool to break fighter stealth is low wave frequency.
It is why the chinese new frigates and destroyers are fitted with low band radars. and so one...
even now a days rwr and irst can alone target a aircraft at bvr ,radar can be used in lower fov for precise attack on stealth fighters
 

SARTHAK

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But it doesn’t a good resolution of the target to direct fire, that is why it can’t be used as a fire control radar only good for detection. Has its own advantages as enhanced situational awareness, but fact will remain that due to low RCS it will be difficult for X-band fire control radars to direct fire at the tango unless it gets too close and by then the tango would break you apart.
even a crude direction coupled with irst can help a great deal
 

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