Fred:

Make a corner reflector screen. Nothing fancy, for this frequency a couple
of square screens a foot or so in size. Put them together at right angles,
put the cell phone at a point which is a quarter wave from both surfaces
(dimension depends on band), and point the whole mess toward where the
signal might be coming from. Watching the "service available" light should
be informative for initial tests.

--
Crazy George
Remove N O and S P A M imbedded in return address