Multiphase differential-phase-modulated pcm repeater

Abstract

Abstract THIS INVENTION RELATES TO APPARATUS AND METHOD FOR DETECTING A 2N-PHASE DIFFERENTIAL-PHASE-MODULATED PCM SIGNAL IN WHICH THE RELATIVE PHASE SHIFT BETWEEN SIGNALS IN ADJACENT TIME SLOTS IS $ (2M-1) $/2N RADIANS, WHERE 2N IS THE NUMBER OF POSSIBLE SIGNAL PHASES,AND M SIGNIFIES ALL THE INTEGERS BETWEEN ONE AND N INCLUSIVE. PHASE DETECTION INVOLVES DIVIDING THE INPUT SIGNAL INTO 2N SIGNAL COMPONENTS, AND THEN COMPARING THE PHASE OF EACH N OF THESE COMPONENTS WITH THE PHASE OF THE SIGNAL IN THE NEXT SUCCEEDING TIME SLOT. THIS IS DONE BY DELAYING EACH OF SAID N SIGNAL COMPONENTS A SPECIFIED LENGTH OF TIME WHICH DEPENDS UPON THE NUMBER OF SIGNAL PHASE STATES. THE SIGNALS PRODUCED AS A RESULT OF EACH OF THESE COMPARISONS ARE AMPLITUDE-DETECTED BY MEANS OF A PAIR OF OPPOSITELY-POLED AMPLITUDE DETECTORS, AND THEN COMBINED IN A COMMON IMPEDANCE TO PRODUCE N BASEBAND SIGNALS WHICH, WHEN TAKEN TOGETHER, CONTAIN ALL THE INFORMATION NECESSARY TO REGENERATE THE INPUT SIGNAL. IN PARTICULAR, ONE OF THE BASEBAND SIGNALS INDICATES THE SIGN ($) OF THE PHASE SHIFT WHEREAS THE SUM OF THE OTHER (N-1) BASEBAND SIGNALS INDICATES THE MAGNITUDE OF THE PHASE SHIFT.

Inventors

• 👤 Stewart E Miller

Bibliographic Details