Russian PESA and AESA Radars

Stealthflanker wrote:
Furthermore..if it can be realized the AESA is the only way to "true time delay" Photonic beamsteering control, where phase shifter is replaced with other means like optic fibre.

It's not a question whether it can be realized, it's whether it can be mass-produced at a cost-effective price. As I stated before, KRET has already announced that they have early working prototypes of photonic based 2nd-gen AESA's, in which they reliably maintain a 10-fold increase in resolution over their contemporary electronic-based 1st-gen AESA counterparts. KRET has also stated that by 2020 their production model 2nd-gen photonic based AESA will increase the superiority of resolution, over contemporary electronic based 1st-gen AESA's, by several dozen times:

https://www.russiadefence.net/t2547p315-russian-radar-systems#92339

in terms of power i dont know how many amperes lets say would be on a single PESA and 30 AESA antenna. problem is if the generator will sustain all. basically as far as i know is like this when in a circuit some things are in series same current go trought all so for PESA and AESA would be same consumption. but there is a problem. some looses exist trought the circuit.

Stealthflanker wrote:

Many people usually emphasize one advantage of the AESA that is dynamic shifted phase, that it can rapidly move the direction of the radar beam due to the rapid shift of the phase of each modules. But PESA like Irbis and Bars can have dynamic shifted phase, too. PESA dynamic shifted phase is relatively bulky and heavy, and the movement of the radar beam is slower, but well the size of Irbis and Bars is acceptable.

You're keep repeating incorrect description. This is not good and can mislead ppl. All ESA Radar regardless whether it's PESA or AESA are able to shift the beam electronically. and there is no correlation at all between size and beam steering time. It's related to phase shifter design. Ferrite phase shifter is known for its relatively slower steer time (in some tens to hundreds of miliseconds) But now we have digital or diode based phase shifter which is faster and used in airborne radar today.

Ferrite phase shifter however are still in use though application might limited to older ESA's such as APQ-164 and S-300's 30N6 radar.

I didn't say that the size and weight of Irbis/Bars make cause slower beam steering time. I just say that the radar is bulkier and heavier. And the radar movement of the radar beam is slower, but I didn't say that it is because of the size of antenna.

Probably my bad in English caused some misunderstanding. What I say here is, many people claimed that only AESA has effective dynamic shifted phase, and these are wrong. PESA has dynamic shifted phase, too.

one i dont understand: how you make beam sterring electronically without moving mecanical parts?

victor1985 wrote:one i dont understand: how you make beam sterring electronically without moving mecanical parts?

By changing the phase of each module

http://www.radartutorial.eu/06.antennas/pic/if3.big.gif

Can some one tell me the difference bewteed BARS and IRBIS , Some one was stating IRBIS is more of hybrid radar ?

Karan of BRF was stating 400 km range of Irbis is only in narrow band something

http://forums.bharat-rakshak.com/viewtopic.php?f=3&t=6842&sid=09f75535375128adbc1b01009f207c79&start=1040#p1893826

Austin wrote:
http://forums.bharat-rakshak.com/viewtopic.php?f=3&t=6842&sid=09f75535375128adbc1b01009f207c79&start=1040#p1893826

He basically state about that 400 Km range is only obtainable through slow scan.

Well that is true for all radar. Not limited to Irbis but also Bars and other fighter radar. One thing that determine the detection range is the received signal energy, the longer radar beam can "dwell" within its search area, the more signal energy it receive thus the longer detection range. This "Dwell time" is also called as "ToT" or "Time on Target"

When searching large volume, scan is deliberately slowed to maintain that ToT. This "slow down" however is of course will be balanced with desired detection probability as the target might be already moved away from the search area before "visited" by the beam thus undetected.


Anyway Richard G Curry's book give quite convenient definitions for this Volume search problem namely :
Detection range : This is basically calculated range come from appropriate radar range equation.
Assured detection range : This range is where the target is assured to be detected, this was taken as 3/4 of detection range
Average detection range at random location within the search volume : Self explained.. This valus is taken as 7/8 of detection range.

Applying it to Irbis (ofcourse with assumption that 400 km range is indeed from volume search) we can see that assured detection range for Irbis for that 3 m sqm is 300 Km and average detection range within its search volume is 350 Km.


Scanning at small volume may also yield long detection range. Thus why we have GCI or AEW, to help cueing fighters to target.

AFAR Modules

that would reduce alot the weight of a system...... they could be easily mounted even on small drones

x_54_u43 wrote:

The 170 g and the 80 g modules are quad modules, each with four T/R elements. Each of the modules on the right consists of one T/R element; so I think four of the modules on the right have a combined mass of less than 10 g.

The scales used for the three module types are not the same.

http://www.ato.ru/content/phazotron-niirs-new-radars

and more exacly those elements what are? transistors?

sepheronx wrote:
Wow, fantastic picture.  Where did you find it?

Helps if you know Russian.

The 170 g and the 80 g modules are quad modules, each with four T/R elements. Each of the modules on the right consists of one T/R element; so I think four of the modules on the right have a combined mass of less than 10 g.

The scales used for the three module types are not the same.

http://www.ato.ru/content/phazotron-niirs-new-radars

I just found the picture, nevertheless it still is very interesting to look at.

victor1985 wrote:and more exacly those elements what are? transistors?

Each of the modules has the digital and the analog (including the microwave) circuitry for one or more transmit/receive (T/R) elements of the AFAR (AESA) array. This circuitry consists of a huge number of transistors (mainly included on monolithic integrated circuits) and other elements. The circuitry realizes the functionalities that include amplification, frequency conversion, controlled phase-shifting (or controlled time delay generation, in nonexportable systems), digital-to-analog conversion (D/A), analog-to-digital (A/D) conversion, signal processing, control, and microwave feed. The images below of an exportable Zhuk-AEh show an AFAR array of 170 of the 170 g quad modules, providing a total of 680 T/R elements.

A backplane controls all of the modules to perform higher functions like beam-forming.

sepheronx wrote:Thanks for the link.  Unfortunately the link doesn't state regarding the other modules being quad or not.  Do you happen to have another link that may break it down more?

As alluded to in the above passage, the quad nature of the 170 g and the 80 g modules can be determined via visual inspection. The structure to the left of the image of the 170 g module are four feeds, the face of which are visible in the array of the Zhuk-AEh shown above.

I have a Fazotron PDF document that covers a lot of this in a lot more detail; I'll try to convert its relevant sections to JPEG images and post them here.

Meanwhile, here is a link—sorry that it's "by" Kopp.

http://www.ausairpower.net/APA-Zhuk-AE-Analysis.html


By the way, the first image is by our own legendary Vitalij Kuzmin.

Morpheus Eberhardt wrote:

Meanwhile, here is a link—sorry that it's "by" Kopp.

http://www.ausairpower.net/APA-Zhuk-AE-Analysis.html

What is wrong with Kopp? Australia Air Power is not a bad site.

x_54_u43 wrote:

Morpheus Eberhardt wrote:

Meanwhile, here is a link—sorry that it's "by" Kopp.

http://www.ausairpower.net/APA-Zhuk-AE-Analysis.html

What is wrong with Kopp? Australia Air Power is not a bad site.

Mainly that it's copy-and-paste based, with a lot of technical and other kind of gross errors.

Morpheus Eberhardt wrote:

x_54_u43 wrote:

Morpheus Eberhardt wrote:

Meanwhile, here is a link—sorry that it's "by" Kopp.

http://www.ausairpower.net/APA-Zhuk-AE-Analysis.html

What is wrong with Kopp? Australia Air Power is not a bad site.

Mainly that it's copy-and-paste based, with a lot of technical and other kind of gross errors.

It has its problems, but I do remember when the F-35 main flight specs were released and APA released a bit more conservative ones, which they got flak for.

Turns out Cockheed Moremoney revised them later down the line and APA was proven right in the end.

"The future radar will be based on the photonic technology that greatly expands the possibilities of communication and radar as their weight will be decreased by more than half and the resolution will increase tenfold."

"The ultra-wideband ROFAR signal allows one to virtually get a TV picture on a radar range. Radio photonic technology, in particular, will enhance the capabilities of the latest generation of Russian airplanes and helicopters."

“After our work on ROFAR, a list of aircrafts both manned and unmanned will be presented with an offer to be equipped with the radar based on radio-optical phased arrays. I think that the PAK FA will also be on this list and there will be specific proposals given to it,” Mikheyev told reporters, adding that the final decision will be taken by the Department of Defense."

http://sputniknews.com/military/20151230/1032493933/russia-aviation-pak-fa-radar.html


"In order for this radar to be defeated, one would have to essentially travel faster than light, or make oneself wholly invisible."
"Since any stealth aircraft can be seen with the naked eye, we know that they give off light. That means they are detectable. You could only be invisible to this radar by quite literally breaking the laws of physics." said Jason McKinney, of the US Naval Research Laboratory regarding photonic radars.

http://www.liveleak.com/view?i=02b_1395416459


"In practice, this means that ROFAR can produce a detailed 3D image of what is happening hundreds of kilometres away. For example, at 400 kilometers it can not only see a person, but even recognize their face", said Vladimir Mikheyev, Advisor to KRET's First Deputy CEO.

"According to KRET, the future ROFAR will be half the weight of the conventional radar system currently being developed for the fifth-generation fighter. Simultaneously, the resolution will be ten times better, making it possible to virtually get a TV picture in the radar range.

"The use of radio-frequency photonic technology allows for a significant reduction of aircraft detectability within the infrared spectrum and of fuel consumption. This is possible due to the high efficiency of the future radar system, which will produce several times less heat, so developers will not have to include an additional powerful cooling system, which would significantly increase the mass of the product and require electricity generated by the aircraft's engines at the cost of burning fuel."

"In addition, it will not be possible to block ROFAR through high-power jamming. For this, the range of the electronic warfare system must be greater than that of the radio receiver, which is physically impossible with photonics-based radar."

"If the ROFAR project is successfully completed, the technology will not only be used for airborne radar systems. According to Mikheyev, equipping new or existing Russian naval ships with ROFAR would make it possible to reduce the weight and size of their onboard antenna systems by approximately 80-85 percent."

http://rbth.com/defence/2016/01/21/with-new-radar-the-pak-fa-fighter-can-detect-any-stealth-aircraft_561275

Arrow wrote:Russia still has no AESA radars in service. And in the West, it's been standard for many years.

Not true, Su-57 is already in service. True that so far PESA were applied but after 25 years underfunding they had to get back to speed. Su-57 is best example of it. In the west there is no more advanced fighter at the moment.



As for PESA Russians put PESA as first electronically scanned radar on MiG-31 in 1981, first in west was 20 years later.
BTW how many in service fighters have AESA and since when?