5N16E Neman-P
The 5N16E Neman-P (named after a river in eastern Prussia) is an experimental S-band (IEEE designation) or E/F-band (NATO designation) early warning and instrumentation radar located at the Sary-Shagan test range in Kazakhstan. Built between 1966 and 1977, and modernized until 2016, it was designed to monitor airspace and confirm flight parameters of target missiles during missile defense system tests, with an instrumented range of 2,000 km. The radar features distinct transmitting and receiving antennas: a 5 × 5 meter active phased array with traveling wave tubes for transmission, and a 7.5-meter diameter Luneburg lens for reception, offering simultaneous reception from all directions and wide bandwidth. The associated "Pilot 2" computing center is housed in the building between the antennas.
radartutorial.eu: https://www.radartutorial.eu/19.kartei/01.oth/karte040.en.html