AN A320 PLT RPTS FALSE TCAS TARGETS ON ARR LEADING TO RA EVASIVE CLBS AND DSCNTS. NO TFC IN ACFT'S VICINITY.

Narrative

DURING ARR TO PHX WE RECEIVED MULTIPLE TCAS RA'S. WE FIRST RESPONDED TO THE CLIMB RA; IMMEDIATELY FOLLOWED BY A DSCNT RA. THE TARGET INITIALLY SHOWED AT OUR ALTITUDE AND LOCATION; THEN TURNED RED FOR OUR AVOIDANCE PROC. THE ACFT TARGET REMAINED AT OUR ALTITUDE AND POSITION THROUGHOUT BOTH MANEUVERS; AS IF TETHERED TO US. WE NOTIFIED ATC AND THEY INFORMED US THEY SHOWED NO TFC IN THE AREA. WE WERE ABLE TO COMPLY WITH THE ARR NAV AND CROSSING RESTRS. WE CONTINUED TO RECEIVE TA'S AFTER WE SELECTED TA ONLY IN VARIOUS POSITIONS RELATIVE TO OUR ACFT. WE CAN ONLY ASSUME ALL RA'S WERE FALSE; AND THE FLT PROCEEDED WITHOUT INCIDENT. APPROPRIATE MAINT RPTING WAS COMPLETED UPON ARR AT PHX.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT A SINGLE FALSE TARGET WAS DETECTED DURING THIS EVENT CAUSING RA'S COMMANDING AN IMMEDIATE CLB FOLLOWED BY A DSCNT. THE CREW RECOGNIZED THE TARGETS AS FALSE AFTER ABOUT 30-40 SECONDS AT WHICH TIME TA ONLY WAS SELECTED. ON FINAL APCH TO THE ARPT; THE CREW WAS UNCERTAIN WHETHER THE TA RPTS ABOUT NEARBY TFC WERE CORRECT OR NOT AND SO IGNORED ALL TCAS RPTS. THIS ACFT HAD NO HISTORY OF TCAS FAULTS PRIOR TO THIS FLT.