It's hard to know what that is. TCAS is a great example of an obvious solution to mid-air collisions - two devices seamlessly negotiate for one plane to go up, the other to go down.

One I can think of is an electronic runway "lock". ATC mark the runway as locked to a particular aircraft. The landing aircraft checks at minimums whether if the runway is locked to any other aircraft. It's harder to know how to prevent incursions at ground level, but it could be a beacon near the runway threshold and intersecting taxiways, flashing a warning in the cockpit of the taxing aircraft if an aircraft on final holds the lock. A pilot could still disregard it. Sometimes two planes can share the same runway, such as a plane lining up while another vacates, which adds further problems.

I'm not aware of any system like this.