Signal interference with nearby aluminum reflectors?
 

I was wondering what effect aluminum foil (used as a radiation heat
shield) would have on GPS signal reception? The scenario is a small
payload container (approx 10" cube) covered in polystyrene, with a
handheld GPS reciever located near the top on one corner.

Would aluminum foil on the inner sides (and/or bottom) interfere with
the reception of the signal? I'm worried about possible reflection or
other mechanisms of interference that might occur and prevent good
reception. Basically, my question is, would foil on the sides or the
bottom pose a reception problem? Are there any "configurations" that
might not pose a problem? (i.e. 2 furthest sides only, half of bottom
only, etc).

Thanks in advance for any insight!
Dave