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radioscienceExperimentswith "Moon-Glob" OrbiterReceiverandBeaconsonMoon'slanders • A.S. Kosov1, O.N. Andreev1, V.M. Aniskovich1, I.A. Babushkin1, S.V. Fedorov1, L.I. Gurvits3, R.S. Kalandadze1, V.V. Korogod1, S.M. Maleev1, V.G. Nechaev1, S.V. Pogrebenko3, V.S. Rozhkov1, D.P. Skulachev1, I.A Strukov1, Y. Sun5, V.K. Sysoev2, S.G. Turyshev4, V.A. Zotov1. • 1 Space Research Institute RAS, 84/32 Profsouznaya, 117997, Russia; • 2 Lavochkin Science Production Association, Chimky, Moscow Region, 24, Leningradskaya St., 141400, Russia; • 3Joint Institute for VLBI in Europe, Dwingeloo, The Netherlands; • 4 JPL,4800 Oak Grove Drive, 91109-8099 Pasadena California Dwingeloo, USA; • 5Center for Space Science and Applied Research, Chinese Academy of Sciences, No.1 NanertiaoZhongguancun, P.O.BOX:8701 Beijing 100080, China. • Contact: email@example.com
Specification of X-band channel • Central frequency: 8400/8420MHz • Irradiated power: 0,3 W, no less • Main beam direction:to the Earth • Beam width : 120 degrees • Polarization type:CR • Modulation type: QPSK, different Fm • Frequency instability (Allan variance), no more: Integration time 3-30 sec:8·10-14 1-300 sec:1·10-13 0,1-10000 sec:1·10-12 24 hours5·10-12 1 year2·10-9
Specification of Ka-band channel • Central frequency:32GHz • Irradiated power: 0,3 W, no less • Main beam direction:to zenith • Beam width : 120 degrees • Polarization type:CR • Modulation type: no • Frequency instability (Allan variance), no more: Integration time 3-30 sec:8·10-14 1-300 sec:1·10-13 0,1-10000 sec:1·10-12 24 hours5·10-12 1 year2·10-9
Modes of operation • 32 GHz signal, only carrier • 8.4 GHz signal, only carrier • 8.4 GHz signal, carrier and ±3 MHz subcarriers • 8.4 GHz signal, carrier and±20MHz subcarriers • 8.4 GHz signal, carrier and±50MHz subcarriers • Internal cyclogram, when beacon will be powered from nuclear source
Navigation task solution • Navigation task - determination of lander’s position with accuracy 10 cm or less. • Method – VLBI. • Planning cyclogram – each lunar day, 12-15 lunar days.
Radio interferometric network "Quasar“, S. Petersburg, 32 m Siberia, 32 m Caucasus, 32 m
Specification of Ka-band receiver • Central frequency:32GHz • Noise temperature:150 K, or less • Antenna main beam direction:to nadir • Beam width : 120 degrees • Polarization type:CR • Bandwidth: 0.5 MHz • Frequency instability of local oscillator (Allan variance), no more: Integration time 3-30 sec:8·10-14 1-300 sec:1·10-13 0,1-10000 sec:1·10-12 24 hours5·10-12 1 year2·10-9
Navigation task and experiment INGL (Investigation of non-uniformaty of Lunar Gravitation)
Bouguer gravity anomaly map from SGM90d. N Namiki et al. Science 2009;323:900-905 Published by AAAS
Experiment GRAIL, NASA, 2012 • GRAIL is the lunar analog of the very successful Gravity Recovery and Climate Experiment (GRACE) twin-spacecraft terrestrial gravity recovery mission that was launched in 2002 and continues to operate. GRAIL will be implemented with a science payload simplified from GRACE and a spacecraft derived from the Lockheed Martin Experimental Small Satellite-11 (XSS-11) launched in 2005. • GRAIL will place two spacecraft (represented as GRAIL-A and GRAIL-B to the left) in a low-altitude (50 km), near-circular, polar lunar orbit to perform high-precision range-rate measurements between them using a Ka-band payload. Subsequent data analysis of the spacecraft-to-spacecraft range-rate data provides a direct measure of the lunar gravity. • The payload, flight system and mission design ensure that all error sources that perturb the gravity measurements are contained at levels well below those necessary to meet science requirements. The figure below illustrates performance margin between the science requirements (red and green), the allocated performance (black), and Current Best Estimate (CBE) performance (gold). These margins enable GRAIL's low-risk implementation
Mutual operation with another instruments • Optical instrument and Ka-band receiver on orbiter could measure 3D displacement of the with respect to lander’s position. • Laser corner reflectors and light emitting beacons on landers will support navigation task. • It is possible to use precise clock of beacons and receiver to synchronize the navigation complex instruments.
Thanks for attention Questions?