How does a TCAS system avoid unnecessary (RAs) resolution advisories when aircraft are operating on separate closely spaced parallel runways (e.g. 2500 feet or less separation between rwy centerlines).
Reference the KSFO Quiet Bridge Visual RWY 28L/R approach: (rwys 28L/R are separated by less than 800 feet)
As an example, suppose there is an aircraft on final approach at KSFO for rwy 28R about 15 miles out and another aircraft is converging and inbound from the southeast past "SIDBY" for rwy 28L. Then suppose the aircraft inbound from "SIDBY" (for rwy 28L) reports seeing the other aircraft (on final for rwy 28R) and is instructed by ATC to maintain Visual Separation (from the aircraft on final for rwy 28R), thereby allowing for separation between both aircraft to possibly become less than standard radar or procedural separation. How does the TCAS system deal with this type of situation and not generate an unnecessary RA?