Universal line concentrator

Claim 1

IN A TELEPHONE SWITCHING SYSTEM INCLUDING A CENTRAL OFFICE HAVING A PLURALITY OF SUBSCRIBER LINE CIRCUITS, THE COMBINATION COMPRISING A CENTRAL OFFICE CONCENTRATING UNIT; A REMOTE CONCENTRATING UNIT; FIRST AND SECOND PLURALITIES OF SUBSCRIBER STATIONS SERVED BY AND CONNECTED TO SAID REMOTE CONCENTRATING UNIT; A SOURCE OF SCANNING PULSES IN SAID CENTRAL OFFICE UNIT; FIRST, SECOND, AND THIRD PLURALITIES OF TRANSMISSION TRUNKS, TOGETHER FEWER IN NUMBER THAN BOTH OF SAID FIRST AND SECOND PLURALITIES OF SUBSCRIBER STATIONS INTERCONNECTING SAID CENTRAL OFFICE UNIT AND SAID REMOTE UNIT; SAID FIRST PLURALITY OF TRANSMISSION TRUNKS BEING CONNECTED THROUGH SAID REMOTE UNIT ONLY TO SAID FIRST PLURALITY OF SUBSCRIBER STATIONS, SAID SECOND PLURALITY OF TRANSMISSION TRUNKS BEING CONNECTED THROUGH SAID REMOTE UNIT ONLY TO SAID SECOND PLURALITY OF SUBSCRIBER STATIONS, SAID THIRD PLURALITY OF TRANSMISSION TRUNKS BEING CONNECTED THROUGH SAID REMOTE UNIT TO BOTH OF SAID FIRST AND SECOND PLURALITY OF SUBSCRIBER STATIONS; MEANS INTERCONNECTING SAID CENTRAL OFFICE UNIT AND CERTAIN OF SAID SUBSCRIBER LINE CIRCUITS, SCANNING MEANS RESPONSIVE TO SAID SCANNING PULSES FOR SIMULTANEOUSLY DETERMINING THE SUPERVISORY STATES OF SAID CERTAIN SUBSCRIBER LINE CIRCUITS AND FIRST, SECOND, AND THIRD PLURALITIES OF TRANSMISSION TRUNKS TO SAID REMOTE UNIT; AND MEANS INCLUDED IN SAID SCANNING MEANS FOR CYCLICALLY SCANNING SAID FIRST, SECOND, AND THIRD PLURALITIES OF TRANSMISSION TRUNKS A PLURALITY OF TIMES FOR EACH SCANNING CYCLE OF SAID CERTAIN SUBSCRIBER LINE CIRCUITS.