AN MD83 FLC GETS 2 TCASII RA'S OFF 1 ACFT WHILE CIRCLING E OF PSP; CA.

Narrative

ATC VECTORED US HIGH AND CLOSE TO THE PSP ARPT FOR A VISUAL TO RWY 13R. WHEN CLRED FOR THE VISUAL; I TURNED E TO ALLOW ROOM FOR THE DSCNT AND THE TURN BACK TO DOWNWIND. WBOUND VFR TFC WAS CALLED BY ATC AND APPEARED ON TCASII. VISUAL CONTACT WAS MADE. PASSING THIS TFC; A 'REDUCE DSCNT' RA WAS GENERATED AND FOLLOWED. NO OTHER TFC WAS OBSERVED ON THE TCASII OR CALLED BY ATC. I TURNED R TO ENTER THE DOWNWIND FOR RWY 13R. DURING THE TURN A TCASII TARGET APPEARED MOVING TOWARD US. THIS TARGET CLOSED ON US AND AGAIN A 'REDUCE DSCNT' RA WAS GENERATED AND FOLLOWED. VISUAL CONTACT WITH THIS 'SECOND' TARGET WAS NEVER MADE NOR DID ATC EVER CALL IT. ONCE 'CLR OF CONFLICT' THE LNDG WAS MADE WITHOUT FURTHER INCIDENT. NOTE: GIVEN THE FACT THAT THERE WERE NEVER 2 TCASII TARGETS EVER PRESENT AND ATC NEVER ADVISED OF ADDITIONAL TFC AND VISUAL CONTACT WAS NEVER MADE WITH THE SECOND TARGET; IS IT POSSIBLE THAT IT WAS IN FACT A 'FALSE' TARGET RETURN FROM THE TFC WE HAD ALREADY PASSED CAUSED BY THE TCASII ANTENNA TILT/ORIENTATION CHANGE DURING OUR TURN (25-30 DEG BANK)?