Nostradamus OTH radar for Stealth detection

[The SC]

The French developed OTH radar using the New Transhorizon Decametric System Applying Studio Methods (Nostradamus) during the 1990s and brought this method in service for the French army in 2005 .
The Nostradamus OTHR, operates in the HF band (3-30 MHz), is developed by the French ORENA aerospace research establishment and is located close to Dreux, approximately 100 km west of Paris. It
consists of 288 emitting and receiving antennas and the antennas are placed in a star pattern with three equally spaced arms.
Based on a star shaped antenna, the Nostradamus OTHR has a detecting range between 800 and 3,000km. A supercomputer, shown in Figure 22, can coordinate all antennas and the signal can be steered over 360°
coverage.
Figure 23 illustrates the underground network construction of the Nostradamus OTHR system that uses a database management system.
The radar is capable of isolating and tracking multiple targets simultaneously in the area.
The French military applied the Nostradamus OTHR in the detection of stealth aircraft and other low observable targets such as cruise missiles with low radar and infrared signature.
The Nostradamus OTHR system is relatively inexpensive since it uses commercial off-the-shelf components.
The Nostradamus OTHR is the first OTHR system built in France and has at least two distinct advantages. First, it is monostatic and the signal is transmitted and received at the same location. In addition, the star-shaped antenna structure, 360° coverage, and a precise tuning of the elevation of the radar beam
provides omnibearing surveillance by collecting the target’s ground coordinates including ground range, ground range rate, azimuth angle, and elevation angle.

http://www.dtic.mil/dtic/tr/fulltext/u2/a474069.pdf

See also:
http://conference-elbereth.obspm.fr/IMG/pdf/45_degurse_elbereth_2013_cle829f9b.pdf