No idea how it's called but you have a system that monitors the complete approach. Too low and off track gives a warning.
Sounds like an ILS to me. I wonder if a ground based system, so close to the runway, to tell the airborne guys that they are off track is the best way to go to solve the problem. There are enough bells & whistles on board, plus 2 sets of eyes, that should be enough. We are sometimes finding that the more back-up error beeping systems there are the less the pilots do their job of monitoring. I saw this attitude in the 80's when an operator graduated from a 3 crew cockpit, needles & dials, to a 2 crew LNAV/VNAV EFIS a/c. We had many cadets coming on board and they were being drummed to "follow the Flight Director" and "there's no need to keep scanning the panels as there are bells & whistles & beepers and flashers to tell you when things go wrong". Oh dear. I tried and failed to stem that heresy. That was 30 years ago & things seems to have evolved to worse not better.