It is a fact that Su-57 has a far superior situational awareness than it’s counterparts. Just read and you’ll definitively see.
Disclaimers: I do not mean to make any one upset, genuinely; but I have noticed that this aspect isn’t covered to the full extent, concisely in one place. This leads to very upsetting misconceptions and outright unawareness to I’d guess 95% of people who talk about it. So, I want to talk very technically about the Su-57’s radar suite and hopefully create a healthy discussion where we can challenge each other to get to the bottom of this. I’m not sure how technical I should be as it can become quite extreme, if you feel like I’ve missed something please do not hesitate to add or counter. Please, I wish to remain anonymous as I solely want to be the messenger, this is also my first post here and I have read the rules. All that I say, and numbers I disclose are declassified to the best of my knowledge. Anything too technical I will cite instead of fully explaining unless anybody want me to after.
Why does Su-57 have better situational awareness?
3x BVR and 1x rear X-band AESA radars (N036)
These radars give the Su-57 a 360° azimuth coverage for aircraft, naval detection and engagement, SAR imaging, electronic warfare, electronic countermeasures, terrain following & avoidance and MAWS.
Analysis: The Main radar N036-1-01 “Byelka”, located at the centre of the bow, has 1,514 TRMs which individually is less than the F-22’s AN/APG-77 1,956 TRM. The misconception is that N036-1-01 lacks nearly a quarter of the AN/APG-77’s TRM, the fact is the Su-57 is fitted with 2x N036B‑1‑01 Side looking X-band AESAs with 404 TRMs. With the process of sensor fusion 1918 (1,514 + 404) TRMs can be used together at once. The N036Kh aft-facing radar information is classified, I’m unable to disclose exact figures but based on public available speculation, it is believed to have about if not the same amount of TRMs as the N036B‑1‑01 of 300 - 400+ - It could be more as it is a mainly stand-alone radar (probably why it is classified). It is located with the electronic warfare/countermeasure system in the dorsal sting between the aircraft’s two engines; thus nicknamed N036kh ‘Sting’. Below is a good attempt of mapping the Su-57’s radar range and coverages. Keep in mind RCS plays a big role in the actual detection range.
^Please understand that the illustration does not accurately depict the azimuth coverages, e.g. the actual frontal radar coverage azimuth is ±110.
8x L-band AESAs (N036L‑1‑01)
Distributed across the airframe for another 360° azimuth coverage, a different frequency used in conjunction with the X-band for enhanced “stealth” detection & tracking, electronic warfare, electronic countermeasures, IFF, passive early warning & long range surveillance, SEAD and multi-spectral targeting. It is important to note that the N036L‑1‑01 it self does not operate as a form of a FCS, it is used in conjunction with the X-bands to enhance it’s range of abilities.
Analysis: These L-band AESAs have 1-2 GHz; This is at the top end of the ultra high frequency band, at the lower end of the microwave range. The exact number of N036L‑1‑01 TRMs is classified information, but based off the design trade-offs typical for L-band AESAs, it is speculated that the TRM count is significantly lower than the X-band TRMs being at a speculative amount of 100-200 TRMs and potentially maybe towards the lower end at the wingtips. Their design is to provide broad, wide‑angle coverage potentially up to ±90° relative to their mounting orientation, with a maximum effective detection range of about 222 km for larger targets, though with lower resolution than the X‑band sensors.
^Illustration unfortunately does not represent the full rear coverage of the N036L‑1‑01 as it doesn’t not take into account the ones at the wingtips.
Electronic Warfare/countermeasures suite (L402 (KRET))
This system is used to detect, analyse, and neutralize enemy radar and communication signals reducing the Su-57’s vulnerability of being detected and targeted. The KRET (manufacturer) suite uses the aft-facing N036Kh and the other N036s but also has it’s dedicated arrays, meaning at the aft of the airframe, both N036kh and the L402 arrays are used.
Analysis: The L402 Himalayas (KRET) and the overall EW/ECM suite is highly classified, including the radar band, exact coverage & range.
^ The Illustration of The KRET system is not very accurate due to highly classified information, “<>” does not mean K-band.
Radio-Optical Phased Array Radar (ROFAR (KRET)) [Upgrade on the way, Su-57M?]
This system is highly advanced, highly complex and naturally extremely classified leading to very limited information since it is in active development. In essence, it is a quantum radar that also uses light hence the “Optical” in some of it’s phases. Do not get it confused with AESAs, it is a different type of array.
This type of radar is the next step up from AESA radars, and currently under consideration as an Su-57 upgrade. To the best of my knowledge, at this time, the ROFAR is immune to jamming. This type of technology is a serious upgrade, it has the ability of bringing the Su-57 or any other aircraft into to 5+ generation aircraft status. Currently, it is a race for such technology. In 2015, KRET established a laboratory dedicated to research in photonics and initiated laboratory tests to create ROFAR. KRET is at the forefront of developing ROFAR technology, aiming to completely revolutionise radar systems by harnessing the advantages of photonics to achieve unprecedented performance levels and even a 1.5 up to 3x weight reduction from AESA systems.
F-22’s AN/APG-77
Developed in the late 80s to early 90s and fully entering service in around 2005, the 1,956 TRMs are old Gallium Arsenide based as at this time when GaAs was well established and mature in western AESA industry, but the N036 was part of the PAK FA program in the mid 2000s, with the radar system being integrated and refined throughout the 2010s while the Su-57 first flight was in 2010. By the 2000s Gallium Nitride was the technology was emerging as a better alternative to GaAs for high‑power TRMs. This timing explicitly highlights that Russian engineers had the opportunity to make modern GaN based TRMs, contrasting with the older GaAs-based AN/APG‑77. AN/APG-77 can receive the GaN upgrades but it won’t because the programme has ceased and is way too expensive. GaN technology offers significant advantages over GaAs namely, higher power output, better heat dissipation, and greater efficiency which can and does translate into increased detection range and overall performance. Official details remain classified, many analysts (e.g., from defence forums and technical papers) lean heavily toward the view that Russia has adopted GaN in its latest AESA systems. I am not confirming that the N036 actually uses GaN since it is classified information, but there is heavy indication that it does.
^AN/APG-77 at the top and the N036 at the bottom. APG-77 uses a flared notch design which was common at the time, the N036 uses a planar configuration; which is better? it is speculated that the flared notch config has advantages in certain scenarios but it is inconclusive and not officially confirmed, not even by Lockheed.