The next generation of satellite laser ranging systems

  • Matthew WilkinsonEmail author
  • Ulrich Schreiber
  • Ivan Procházka
  • Christopher Moore
  • John Degnan
  • Georg Kirchner
  • Zhang Zhongping
  • Peter Dunn
  • Victor Shargorodskiy
  • Mikhail Sadovnikov
  • Clément Courde
  • Hiroo Kunimori
Original Article


Satellite laser ranging (SLR) stations in the International Laser Ranging Service (ILRS) global tracking network come in different shapes and sizes and were built by different institutions at different times using different technologies. In addition, those stations that have upgraded their systems and equipment are often operating a complementary mix of old and new. Such variety reduces the risk of systematic errors across all ILRS stations, and an operational advantage at one station can inform the direction and choices at another station. This paper describes the evolution of the ILRS network and the emergence of a new generation of SLR station, operating at kHz repetition rates, firing ultra-short laser pulses that are timestamped by epoch timers accurate to a few picoseconds. It discusses current trends, such as increased automation, higher repetition rate SLR and the challenges of eliminating systematic biases, and highlights possibilities in new technology. In addition to meeting the growing demand for laser tracking support from an increasing number of SLR targets, including a variety of Global Navigation Satellite Systems satellites, ILRS stations are striving to: meet the millimetre range accuracy science goals of the Global Geodetic Observing System; make laser range measurements to space debris objects in the absence of high optical cross-sectional retro-reflectors; further advances in deep space laser ranging and laser communications; and demonstrate accurate laser time transfer between continents.


Satellite laser ranging Space geodesy ILRS network Next generation Automation Laser transponders 



The authors would like to acknowledge all the design, analysis, maintenance, development and operational work undertaken by the great number individuals in the global ILRS community now and over the history of laser ranging. This work ensures the highest quality data and products and the greatest impact from SLR.


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Authors and Affiliations

  1. 1.NERC Space Geodesy FacilityHailshamUK
  2. 2.FESG, Geodätisches Observatorium WettzellTechnical University of MunichBad KötztingGermany
  3. 3.Czech Technical University in PraguePragueCzech Republic
  4. 4.EOS Space Systems Pty. Ltd.QueanbeyanAustralia
  5. 5.Sigma Space CorporationLanhamUSA
  6. 6.Space Research Institute of the Austrian Academy of SciencesGrazAustria
  7. 7.Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghaiChina
  8. 8.Research-and-Production CorporationPrecision Systems and InstrumentsMoscowRussia
  9. 9.CNRS, Observatoire de la Côte d’Azur, IRD, GéoazurUniversité Côte d’AzurCaussolsFrance
  10. 10.National Institute of Information and Communications Technology (NICT)KoganeiJapan

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