NMAC DURING A TFC PATTERN PROC.

Narrative

AT THE END OF A LCL PLEASURE FLT; I WAS IN CONTACT WITH COAST APCH BEING VECTORED TO A STRAIGHT IN APCH TO RWY 1L AT SNA. I WAS DIRECTED TO THE FINAL APCH PATH BEHIND AN AIRLINER JUST AHEAD. I WAS DIRECTED TO MAKE BEST SPD TO THE RWY DUE TO FOLLOWING TFC; ANOTHER AIRLINER; AN LTT; I BELIEVE. WHEN DIRECTED TO SWITCH FREQ TO THE SNA TWR; IT WAS OBVIOUS THE NUMEROUS ACFT WERE IN THE PATTERN FOR RWY 1L; IN ADDITION TO THE 3; INCLUDING MYSELF; ON STRAIGHT IN. ONE OF THE ACFT ON DOWNWIND HAD THE SAME CALL SIGN AS MINE WITH THE EXCEPTION OF THE LAST LETTER. AFTER MY RPT TO THE TWR AND CLRNC GIVEN TO LAND; THAT ACFT RPTED TURNING TO BASE AND THE TWR GAVE HIM CLRNC TO LAND ALSO. IT WAS APPARENT THE CTLR THOUGHT HE WAS DEALING WITH 1 ACFT INSTEAD OF 2. I WAS UNABLE TO BREAK IN ON THE FREQ DUE TO THE HVY CTLR WORKLOAD UNTIL HE WAS TURNING BASE TO FINAL DIRECTLY IN FRONT OF ME. AT THIS POINT; THE CTLR DIRECTED ME TO IMMEDIATELY START A L 360 DEG TURN. THIS CAUSED ME TO PASS BTWN 2 OTHER ACFT IN CLOSE PROX THAT WERE THEMSELVES TURNING ON DOWNWIND AND BASE. COMPLETION OF THE TURN BROUGHT ME BACK INTO THE FINAL APCH COURSE DIRECTLY IN FRONT OF THE LTT THAT HAD BEEN FOLLOWING ME ON FINAL PREVIOUSLY. THE CTLR THEN DIRECTED A SECOND 360 WHICH WHEN COMPLETED WAS FOLLOWED BY LNDG. I FEEL THE CTLRþS WORKLOAD WAS TOO HIGH AND ATTN TO DETAIL DIMINISHED; WHICH ALLOWED THE IDENT MISTAKE. I FEEL THAT I SHOULD HAVE BEEN DIRECTED TO GAR RATHER THAN TO MAKE 360 DEG TURNS IN THE MIDDLE OF A CROWDED PATTERN. THE HAZARD LEVEL TO MYSELF AND OTHER ACFT WAS TOTALLY UNACCEPTABLE. NOTE: ON ROLLOUT AFTER LNDG THE CTLR INVOLVED AGAIN CALLED ME BY THE OTHER PLANEþS CALL SIGN.