Tom,

Yes, an identical redundant back-up should double the volume, price, and area requirements.  It probably also doubles the power consumption, although you could also argue that only one of the two systems needs to be powered-up at any given time.

As far as which sensor got the back-up, I don't know.  I suspect the AEMS was redundant, since it is a search sensor and the LIDAR isn't.  My suggestion would be to try it - the AEMS and LIDAR systems likely have different volume, area, power, and price requirements, and therefore you should come close to the published figures one way and be relatively far off if you go the other.

---Guy "wildstar" Garnett
xxxxxx@prismnet.com