The Nizhny Novgorod Research Institute of Radio Engineering (NNIIRT) is a Russian electronics company specializing in the development and manufacturing of radar equipment. It is a subsidiary of the Almaz-Antey group.
Founded in 1947, NNIIRT is based in the city of Nizhny Novgorod.
Beginning in 1975, NNIIRT developed the first VHF 3D 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 postâÂÂCold 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.
The Nizhny Novgorod Research Institute of Radio Engineering (Russian acronym: NNIIRT) has since 1948 developed a number of radars.
Other innovations were radars with frequency hopping; the P-10 Volga A (NATO: KNIFE REST B) in 1953, radars with transmitter signal coherency and special features like moving target indicator (MTI); the P-12 Yenisei (NATO: SPOON REST) in 1955, as well as the P-70 Lena-M with chirp signal modulation in 1968.