Decoder
The OVLBI Decoder performs three main functions; 1) reconfiguring
the downlink I, Q and Clock to the form by the VLBA formatter,
2) precisely recording the time of arrival of satellite data frames, and
3) extracting the satellite telemetry data.
The I, Q and Clock signals are sent down from the OVLBI
Demodulator in the antenna vertex
electronics rack. The output data stream is provided to the
VLBA formatter and the OVLBI optical modum.
The Decoder is built on two 6U wire wrap cards. The two Decoder boards
are shown above in their test fixture.
VME rack
The Decoder is installed in the VME rack containing the station computer
and optical modum. The communication to the station computer is via
the VME bus. The decoder also supports RS-232 communication for
diagnostic purposes.
Related Web Sites
Return to the OVLBI Hardware Page or the
OVLBI Home Page.
VSOP/HALCA has a home page.
The
VLBA Correlator
NRAO Socorro is developing other hardware and software for the
NASA OVLBI project.
There is a
Space VLBA Correlator
home page as well.
Return to the Station Software Guide.
The National Radio Astronomy Observatory
(NRAO)
is a facillity of the
National Science Foundation
operated under cooperative agreement by
Associated Universities, Inc.
glangsto@nrao.edu Last update: 98 January 16