Here is a URL that expains what you are looking for. http://www.cisco.com/en/US/products/hw/phones/ps379/products_implementation_design_guide_chapter09186a00802a0a1e.html
You might want to replace the cable to rule out it being defective. Then try uprgrading to 12.04 for the bridge if the cable change did not work . Here are the release notes.http://www.cisco.com/en/US/products/hw/wireless/ps458/prod_release_note09186...
Not knowing how the antenna was attached to the roof, I suggest you take a couple of adjustable wrenches in case there are bolts holding the antenna onto a mast, a slotted head (flat head) screwdriver, a Phillips head screwdriver in case the antenna ...