Welcome to the VLBI standards website.

The intention of this site is to bring together the currently active VLBI standards at a single reference site. The current standards that are covered are:

VLBI Experiment Definition (VEX) - a framework for defining the setup details and schedule for a VLBI experiment. First defined in 1995, VEX has been widely adopted by the geodetic-VLBI community, and is more recently being adopted by the global astronomical-VLBI community as well. Efforts are now (2010) underway to extend VEX, called 'VEX2' to properly support new VLBI equipment and more complex experiments.

VLBI Standard Interface (VSI) - ratified in 2000 as a standard electrical/timing (VSI-H) and supporting software (VSI-S) specification; VSI has now been adopted in a number of various pieces of VLBI equipment developed at various institutions worldwide.

VDIF Transport Protocol (VTP) - VTP defines how VDIF data should be streamed over standard network connections such as Ethernet.

VLBI Data Interchange Format (VDIF) - ratified in 2009 as a standardized VLBI raw-data format that is compatible with both recording systems and network transmission. VDIF is increasingly being adopted by the VLBI community.

VLBI File-Naming Conventions - in order to facilitate global VLBI data transfers, a file-naming convention for VLBI raw-data files was adopted in 2009.

VLBI On-line Technical Documentation - links to known VLBI Technical information at institutes around the globe. Please contact the site administrator if you have links to information that should be added.

Please send comments, suggestions, requests to:
VLBI-admin at haystack(dot)mit(dot)edu