  The SRT (Sardinia Radio Telescope) is a general purpose, fully steerable,
active surface equipped, 64 meters antenna, which is in an advanced
construction state near Cagliari (Sardinia - Italy). It will be an antenna
which could improve a lot the performances of the EVN network, particularly at
frequencies higher than 22 GHz. The main antenna geometry consist of a shaped
reflector system pair, based on the classical parabola-ellipse Gregorian
configuration. It is designed to be able to operate with a good efficiency in a
frequency range from 300 MHz up to 100 GHz. This frequency range, is divided in
two parts which define also two antenna operational modes, one up to 22 GHz
with a minimal amount of accessory instrumentation, and the other up to 100 GHz
with a full complement of instrumentation. The goal is to make it possible to
build a telescope operable up to 22 GHz, and then upgrade it at a future date
to operate at frequencies up to 100 GHz. In order to get these goals, the SRT
Metrology group is studying and developing different types of strategies,
instrumentation, and techniques for measuring and reducing the various
components of pointing and efficiency errors, taking advantage also from
experiences developed in other radio telescopes, like GBT (Green Bank
Telescope, USA), LMT (Large Millimiter Telescope, MEX), and IRAM (Institut de
Radio Astronomie Millimetrique, Fr). Many of those system will be installed and
tested at the 32 meters radio-telescope in Medicina (Bologna), before of their
implementation on SRT.
