We report on the implementation of a new infrared detection at the Grasse lunar laser ranging station and describe how infrared telemetry improves the situation. We present our first results on the lunar reflectors and show that infrared detection permits us to densify the observations and allows measurements during the new and the full moon periods. We also present the benefit obtained on the ranging of Global Navigation Satellite System (GNSS) satellites and on RadioAstron which have a very elliptic orbit.
In collaboration between CNES, NICT, Geoazur, the first successful lasercom link between the micro-satellite SOCRATES and an OGS in Europe has been established. This paper presents some results of telecom and scintillation first data analysis for 4 successful links in June & July 2015 between SOTA terminal and MEO optical ground station (OGS) at Caussols France. The telecom and scintillation data have been continuously recorded during the passes by using a detector developed at the laboratory. An irradiance of 190 nW/m2 and 430 nW/m2 has been detected for 1549 nm and 976 nm downlinks at 35° elevation. Spectrums of power fluctuation measured at OGS are analyzed at different elevation angles and at different diameters of telescope aperture to determine fluctuations caused by pointing error (due to satellite & OGS telescope vibrations) and caused by atmospheric turbulence. Downlink & Uplink budgets are analyzed, the theoretical estimation matches well to measured power levels. Telecom signal forms and bit error rates (BER) of 1549 nm and 976 nm downlink are also shown at different diameters of telescope aperture. BER is 'Error Free' with full-aperture 1.5m telescope, and almost in ‘good channel’ with 0.4 m sub-aperture of telescope. We also show the comparison between the expected and measured BER distributions.
Improving orbital accuracy of space debris is one of the major prerequisite to performing reliable collision prediction in
low earth orbit. The objective is to avoid false alarms and useless maneuvers for operational satellites. This paper shows
how laser ranging on debris can improve the accuracy of orbit determination.
In March 2012 a joint OCA-Astrium team had the first laser echoes from space debris using the MéO (Métrologie
Optique) telescope of the Observatoire de la Côte d’Azur (OCA), upgraded with a nanosecond pulsed laser. The
experiment was conducted in full compliance with the procedures dictated by the French Civil Aviation Authorities.
To perform laser ranging measurement on space debris, the laser link budget needed to be improved. Related technical
developments were supported by implementation of a 2J pulsed laser purchased by ASTRIUM and an adapted photo
detection. To achieve acquisition of the target from low accuracy orbital data such as Two Lines Elements, a 2.3-degree
field of view telescope was coupled to the original MéO telescope 3-arcmin narrow field of view. The wide field of view
telescope aimed at pointing, adjusting and acquiring images of the space debris for astrometry measurement. The
achieved set-up allowed performing laser ranging and angular measurements in parallel, on several rocket stages from
After a brief description of the set-up, development issues and campaigns, the paper discusses added-value of laser
ranging measurement when combined to angular measurement for accurate orbit determination. Comparison between
different sets of experimental results as well as simulation results is given.