Time division multiplex optical communication system

Abstract

Abstract Time-division multiplexing and demultiplexing of N optical, pulse code modulated signals is achieved by means of a cascaded array of N polarization rotators and associated polarization selective prisms. At the multiplexer, the N pulse-encoded signals, polarized along a first direction, are coupled bit-bybit into the respective rotators by means of their associated prisms. Simultaneously, pulses, having a repetition rate equal to the bit rate of the individual signals are applied to all of the rotators, including a 90* rotation in the direction of polarization of the signals. This permits the signals to pass through the rotator-prism pairs and to enter into a common transmission path as a time-division multiplexed signal. At the receiver, the multiplexed signal enters a demultiplexer comprising an identical array of polarization rotators and polarization prisms. Simultaneously, synchronized pulses, applied to the rotators, effect a 90* rotation in the direction of polarization of the signals, causing the prism to deflect each of the signals, bit-by-bit along W different wavepaths. In a second embodiment, traveling electrical pulses are employed to produce the 90* rotation of the signal polarization.

Inventors

• 👤 Ivan Paul Kaminow

Bibliographic Details