NIIRP

The Nizhny Novgorod Research Institute of Radio Engineering (NNIIRT) is a Russian electronics company specializing in the development and manufacture of radar equipment. Founded in 1947, it is based in the city of Nizhny Novgorod. It is a subsidiary of the Almaz-Antey group.

Beginning in 1975, NNIIRT developed the first '3D' VHF radar capable of measuring height, range, and azimuth to a target. This effort produced the 55Zh6 'Nebo' VHF surveillance radar, which passed acceptance trials in 1982.

In the post–Cold War era, NNIIRT developed the 55Zh6 Nebo U 'Tall Rack' radar, which has been integrated with the SA-21 anti-aircraft weapons system. This system is deployed around Moscow.

In 2013, NNIIRT announced the further development of the 55Zh6UME Nebo-UME, which combines VHF and L band radars on a single assembly.

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