all it says in Haynes is:
"The central control unit is located in the back of the fusebox below the drivers side fascia"
"The CCU is responsible for controlling the central door locking and alarm/immobilisation functions"
from this, I'm not sure it has it's own receiver, but I do recall reading something on here about an aerial for it being behind the dashboard. when I say aerial, probably only a length of cable.
what makes you think you have a problem with it ?