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A New LO/IF Transmission System

To transmit up to 16 GHz of total bandwidth from each antenna, we will use optical fiber links to all of the VLA stations, to the nearby VLBA antennas and to the new antennas in the A+ configuration (§2.7). Separate fibers will carry the LO reference signal and the wide-band IF signal. Between four and six single mode fibers will run to each antenna station. Although low temperature coefficient fiber will be used on runs exposed to ambient temperature, a round trip phase correction system probably will still be needed. The detailed design will be based on the MMA development of a similar system and on experience gained with the VLA-to-Pie-Town link project. An important ingredient for using the more remote antennas with the VLA will be to explore the use of commercial digital networks to transmit the IF signals.



Michael Rupen
Fri Mar 26 15:30:00 MST 1999