The NIIDAR company, the Scientific and Research Institute for Long-Distance Radio Communications (Russian: Научно-исследовательский институт дальней радиосвязи) is a Russian manufacturer of radar systems.

[1] It developed a number of radars from 1949 to 1959 in co-operation with the NII-20 Lianozovo Electromechanical Plant.

[2] Unlike the NNIIRT, this design bureau focused on higher frequency radars like the P-20, P-30, P-30M, P-35, P-32D2 and the P-50 (NATO: E/F-bands).

These radars have better accuracy and faster scan rates, and are thus more suited for ground control of fighter aircraft, which complement the lower frequency radars developed by the NNIIRT design bureau.

[4] The latter, while also being an OTH-radar, has separate locations for the transmitter and the receiver making it a bi-static system.