How do preceding aircraft affect the ILS signals? (airliners.net) Planes on approach in sequence to London Heathrow.

When LVP is in effect, the ILS area is protected.

I'm wondering, when there is a queue to a runway, how does the long queue affect the signals for those behind?

I'm guessing it does somehow, and the answer may shed some light on the new Enhanced ILS.
I've never noticed any perturbation of the ILS signal from aircraft ahead in flight. Aircraft on the ground crossing the runway, absolutely yes. Something big enough (747 or A-380) exiting at the far end, perhaps briefly, but not generally something you notice.

I'll let somebody else explain the theory, but that's my observed results.