PKD instrument for “INGL” experiment

PKD (Ka-band receiver) instrument, a part of science payload of “Luna-Glob” mission spacecraft, is designed for navigational task and “INGL” experiment. The “INGL” experiment involves a gravity field measurement around “Luna-Glob” and “Luna-Resource” moon probe landing locations. The instrument receives the landing module beacon signal to accurately and precisely measure the changes in the spacecraft speed around beacon using Doppler frequency shift. The accuracy of the experiment is determined by the frequency stability of the beacon ultra-stable oscillator and the Doppler shift measurement accuracy of the PKD instrument. With the 30 seconds accumulation time, overall beacon and receiver frequency instability will be about 10^-13, leading to 0.003 Hz signal frequency measurement error at Ka-band and acceleration measurement error of about 3 mGal.