Groundrules:

• OVSA observations will not be compromised; so all signals and control room utilization will be separate from current system.
• Broadband RF will be piped into the control room for further processing.
• All data processing after digitizer will be software-based.

Required Components

Phase 1

• 1-18 GHz splitters to split OVSA RF signals (3)
• Optical links (transmitters, receivers, fiber) for RF (3)
• Optical breakout boxes at antennas (buried?) (3)
• RF Amplifier (1-12 GHz) to boost signal from optical link (3)
• 1-12 GHz mixer (3)
• Tunable LO system (generated by YIG) (1)
• Filter bank to implement switchable IF bandwidth (3)
• IF amplifier (to 500 MHz) (3)
• Digitizer (up to 1 Gs/s) (3 channel)
• Storage and analysis PC (1)
• Control system (to tune YIG, switch bandwidth, initiate data capture)

Phase 2

• 1-18 GHz RF switch (3)
• Fixed 12 GHz LO source (1)
• Additional optical link (transmitters, receivers, fiber) for LO (3)
• Phase lock system?
• 12 GHz mixer (3)

Other Questions

• Do we need phase switching for DC stabilization, sine/cos components? How do we implement that?
• What control room space will be needed? One rack plus one or two PCs?
• We will need new trenches for optical fiber. How deep, 1 meter or more? This may be difficult given the existing buried cable. Are we going to use equal lengths?
• Should we investigate using hardware correlation instead of software?
• What is the basic design of the software correlator?
• Do we need gain control?
• What are the issues this system will resolve in the prototype stage? A software correlation may not be wise for phase stability studies.
• What calibrations are needed, and how will they be done?