[Discuss-gnuradio] Query: using the USRP in optical interferometry

[Richard]

Dear All,

I've just joined this list, and I'm trying to find out whether a USRP 
could be used/modified in an unusual way.

What we're trying to do is build an interface for a HAWAII Focal-Plane 
Array (basically, a 1 Mpixel CCD that is sensitive to the far Infrared, 
and works in Liquid Nitrogen) - the use would be for the COAST and MRO 
telescopes.

The requirements are these - I'd be very grateful for some advice as to 
whether I'm on a fruitful track or not:

* 4 channels (1 quadrant each), each able to sample at upto 1M sample/sec.

* Inputs are DC-coupled, and full swing is 0.4 - 1.0 Volt.

* Resolution required is 16 bit (could a 14-bit ADC do it, with 
dithering?)

* Low noise and self-interference (eg clock coupling into inputs).
  [we're trying to catch a few photons at a time]

* External synchronisation of the ADC sample-clock, OR 24 channels of
  10MHz digital I/O.


Is this possible? Could it be made to work? I'm currently going slowly mad 
over a custom-built system!

Thanks very much for your help,

Richard


--
address@hidden   http://www.richardneill.org
Trinity College, Cambridge, CB2 1TQ