Post

Please be aware that this noted as a “Top Secret” project within The Western Isles region and the admin wishes this to be respected.
Blatant copy-pasting and mimicking of this project, whilst it is noted as Top Secret by the admin (Franco-albion), is not tolerated.
Nations outside of The Western Isles region may refer to this system and link back to this dispatch, but not copy and claim this original content as their own.
This work is protected by protected by the Creative Commons Attribution-(Share Alike) license;
thus all works based on this project should linked back to this as a source – as dictated by US and International Law.

Patet Visus (latin for 'Clear Sight'), is the codename of a top-secret project administered by the Franco-Albion Ministry of Defence, along with elements from the private sector: Union Arms and System (now part of the Franco-Albion Aircraft Company/Corporation); along with defence experts and think-tank FanatiQ. This highly expensive project was set up to protect Franco-albion airspace against aircraft that had strong stealth designs, detecting such craft at a range and relaying the information to appropriate air-defence assets. The project, along with the exact workings, is highly classified and not publicly acknowledged by the Commonwealth Government.

In summary, Patet Visus is a system of radar arrays and receivers, designed to detect and evaluate the signatures of ‘stealth’ designed aircraft and surface vessels. It does so by sending out a radar signal from one (or more) radar transmitters, then instead of listening for the reflected signal in the same spot (as in most radar systems - Monostatic), it listens for a potential response from a wider number of locations. Patet Visus is described as a Polystatic Radar transmitter system, that has a successful detection rate (of stealth aircraft) of around 70% and produces less an 2% false-positives.

Universally used Monostatic Radar systems find it
difficult detect stealth aircraft, as very little of their
signal is returned in the same direction to the transceiver.

Most current efforts to detect stealth aircraft focus on one of two points – heat emissions and ‘accidental’ signals (detected during the opening and closing of weapon bays), using conventional radar systems. Detecting heat emissions is, technically, an accurate method of countering stealth aircraft. Even the advanced airframes of aircraft such as the F-22 Raptor and F-23 Black Widow, both with specially engineered engines that diffuse much of the heat, still produce significant infra-red signatures. These signatures are detectable using specialised systems, such as the IRST system employed by the Eurofighter, Poley and Sariel. However, the system is only effective at shorter ranges (usually around 50km), making it practically useless for long range detection and early warning.

The second method of detecting ‘accidental signatures’, is too easily countered by simply closing weapon bays and jamming technology – leading it to be a half-hearted and impractical method of reliably detecting aircraft. It remains to be the main of detecting radar-reducing signatures.

Stealth technology, whilst only beginning to emerge in the region, has been in development for a long time. The F-117 Nighthawk was the stealth fighter that captivated the world in the 1990s, though initially developed on the primitive computers of the 1970s. Since then, there have been many types of aircraft developed with stealth characteristics including Franco-albion’s P.125 Gabriel and the UAS Puriel.

With subsequent stealth designs, all these aircraft try to reduce their radar signature. However, as discovered with the F-117 and later aircraft, it was impossible to completely eliminate a radar signature. Instead, a combination of absorbent coating and reflective panels (to reflect the radar signal in a different direction) to reduce a signature reflected to the static radar and receiver. As the aircraft is able to reflect the signal mostly away in a different direction, the Radar receiver (located at the same point as the transmitter) gathers a very small and weak signal, which can’t be clearly identified as an aircraft.

The Clear Sight system uses the Polystatic system, where
the receiver is located in a series of towers away from the
transmitter; thus more likely to intercept a reflected signal.

The system, protected by a region-wide decree, was designed to exploit the flaw in stealth design. The aforementioned system was designed to counter a so called ‘Monostatic Radar’ - where the radar transmitter and receiver is located within the same unit - leaving an incredibly small and weak detectable return signal.

Patet Visus operates a system where instead of having a transmitter and receiver in the same location (as in monostatic systems), the Patet Visus system places the two parts apart from each other. However, operating such a system requires huge processing power to compute the data. The issue is computing the scale and coordination of the stealth signature. The stealth aircraft will be visible only if there is an ideal alignment of the transmitter, signal and receiver.

The Clear Sight system solves the problem with some creative thinking and incredible levels of computing power. One could build a series of monostatic radar systems every few miles, but the cost would be astronomical to maintain and construct. Radar, in layman’s terms, is simply an application of radio waves: which are present everywhere in today’s society. Particularly, in industrialised nations, mobile/cell towers are commonplace. In effect, the Clear Sight system uses these cell towers (though supplemented by dedicated towers for the detection task) to receive and monitor returning signals from the transmitter sites.

The sheer number of towers is not a major concern, as they are cheap to construct and maintain, whilst having a small footprint and are easily installed and replaced.

“A lot of stealth technology deals with redirecting radar waves,” said Alfred Knockwell, a Principal Scientist at FanatiQ working on underwater acoustics in an area very much analogous to radar. ”It’s very effective against monostatic radars. However, if you have polystatic radars, in particular a very large number of sources, so that you excite the target from a wide range of angles, and you have a multiplicity of receivers in many locations, you essentially will get around the stealth target’s redirection capabilities. It is highly likely that an incident wave from a transmitter station will be redirected towards one or more receivers.”

Being able to detect a reflected signal from a stealth aircraft, the system builds a picture using the data. Using the computer power of a dedicated and high-powered computing system, this data can be analysed and build a comprehensive and coherent picture, making it possible to detect stealth aircraft. Once this data has been analysed, it can be forwarded instantaneously to operating aircraft and air defence networks.

Once the system is operational, it will be able to determine a wide range of variables from incoming signals, turning it into useful data for defence forces. Using the principle of the Doppler effect, it is possible to determine the speed of the attacker. If the return signal is precise and clear enough, it is possible to calculate frequency effects – such as engine rotation and structural outlines – even able to identify the exact type of aircraft.

Traditional radar efforts, when detecting stealth signatures, tend to filter out small signal returns by the operator or the radar’s systems – usually assuming the small return to be a bird. However, with the enhanced signal strength and computing power, it is able to distinguish between birds by looking for the tell-tale signs of stealth aircraft signatures and characteristics.

“If you can get a radar return, you can get all kinds of information from the return signal if you can process it sufficiently,” Knockwell said. “For example, if you an look at the Doppler shift of the returned signal, you can get aircraft velocity. If you are sensitive enough, you can see frequency effects, such as engine rotation or structural vibration. If you have several receivers or different imaging angles, you can begin to reconstruct an image of the target.”

Development of the system was originally planned for a static system on land. A similar system, to be deployed in the air, utilises AWACs and Electronic Warfare aircraft, such the UAS Puriel with a dedicated pod, or the soon-to-be-released Metatron aircraft.