The ground-based tracking station is an integral part of Spektr-M ground-based scientific complex and it operates in conjunction with the onboard high ratio data transmission radio complex (VIRK-M), forming the spacecraft-Earth radio link.
Ground Tracking Stations:
Spektr-M spacecraft will be located in halo orbit near the Lagrange point (L2) of the Sun-Earth system. Due to its great distance that is more than 1.5 million kilometers from the Earth, it is necessary to use ground antennas with the mirror diameter of at least 40 meters in order to compensate the signal attenuation in outer space. In Russia, such antennas can be RT-64 (Kalyazin) and RT-70 (Yevpatoriya).
Example of possible ground tracking stations for Millimetron observatory: Kalyazin (64 meters), Evpatoriya (70 meters)