eVLBI Development in TIGO

  • Sergio K. Sobarzo
  • Sergio N. Torres
  • Hayo Hase
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4225)


Very Long Baseline Interferometry (VLBI) is a geometric technique which measures the time difference between the arrivals of a radio wavefront emitted by a distant quasar to at least two Earth based radio telescopes. Because the time difference measurements are precise to a few picoseconds, VLBI determines the relative positions of the cooperating radio telescopes to a few millimeter and the positions of the quasars to a few milliarcseconds. The transfer of the collected data from the radiotelescopes to the correlation centers is made through physical shipment of data discs which implies a delay of weeks in the turnaround. eVLBI is a technique which allows the direct transmission of the data to the correlators through Internet with multiples advantages. TIGO is a VLBI station located in Concepción, Chile with a limited bandwidth of few Mbps which must be increased in order to achieve an usable speed to work as an eVLBI station. The challenge and approaches to dodge the difficulties of achieving eVLBI in TIGO are explained in the present paper.


Astronomy Geodesy VLBI Network Internet Multipath Routing 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Sergio K. Sobarzo
    • 1
    • 2
  • Sergio N. Torres
    • 1
  • Hayo Hase
    • 2
  1. 1.Department of Electrical EngineeringUniversity of ConcepciónConcepciónChile
  2. 2.Transportable Integrated Geodetic Observatory (TIGO)ConcepciónChile

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