  In almost 30 years of operation, the Very Large Array (VLA) has proved to be
a remarkably flexible and productive radio telescope. However, the basic
capabilities of the VLA have changed little since it was designed. A major
expansion utilizing modern technology is currently underway to improve the
capabilities of the VLA by at least an order of magnitude in both sensitivity
and in frequency coverage. The primary elements of the Expanded Very Large
Array (EVLA) project include new or upgraded receivers for continuous frequency
coverage from 1 to 50 GHz, new local oscillator, intermediate frequency, and
wide bandwidth data transmission systems to carry signals with 16 GHz total
bandwidth from each antenna, and a new digital correlator with the capability
to process this bandwidth with an unprecedented number of frequency channels
for an imaging array. Also included are a new monitor and control system and
new software that will provide telescope ease of use. Scheduled for completion
in 2012, the EVLA will provide the world research community with a flexible,
powerful, general-purpose telescope to address current and future astronomical
issues.
