Abstract: A fiber optic telecommunication system has master site linked to a plurality of subscriber interface sites by a single pair of optical fibers. Downlink messages are transmitted in a continuous TDM format over a first optical fiber from the master site to subscriber interface sites, and in a burst mode TDMA format over a second optical fiber from the subscriber interface sites to the master site. Each subscriber interface site is coupled to the optical fiber link by way of a multiple fan-out fiber coupling pedestal at a common location on the fiber pair. To prevent collisions between successive uplink bursts from the subscriber interface sites, a guard band separates successive uplink messages from one another. The guard band duration accommodates optical fiber transmission distance between the common location on the uplink optical fiber and the subscriber interface site whose differential optical fiber transmission distance from the common location is greatest.

Abstract: A fiber optic telecommunication system has master site linked to a plurality of subscriber interface sites by a single pair of optical fibers. Downlink messages are transmitted in a continuous TDM format over a first optical fiber from the master site to subscriber interface sites, and in a burst mode TDMA format over a second optical fiber from the subscriber interface sites to the master site. Each subscriber interface site is coupled to the optical fiber link by way of a multiple fan-out fiber coupling pedestal at a common location on the fiber pair. To prevent collisions between successive uplink bursts from the subscriber interface sites, a guard band separates successive uplink messages from one another. The guard band duration accommodates optical fiber transmission distance between the common location on the uplink optical fiber and the subscriber interface site whose differential optical fiber transmission distance from the common location is greatest.

Abstract: A Time Divison Multiplex Ring (TDM Ring) comprising a plurality of nodes (central offices) connected together by interchange trunks (main and standby paths) in a ring type configuration.

Abstract: A fiber optic Local Area Network containing more than one transmitter-receiver combination capable of transmitting and receiving light energy over optical fibers and being deactivatable during transmission upon receiving a jam signal, a coupler means, a collision detection means for detecting when more than one transmitter is transmitting at the same time, and a plurality of optical fibers connecting the coupler means to said transmitter-receiver combinations and forming transmitting and receiving light paths there between, the collision-detection means comprising a tap means connected to each transmitting optical fiber for diverting a portion of the transmitted light energy; an optical receiver means for each optical fiber containing a tap adapted to detect that portion of an optical signal diverted by said tap means; an optical path between each tap means and a single optical receiver means; a logic means connected to said optical receiver means responsive to and adapted to transmit a predetermined signal w

Abstract: A repeatered, multichannel fiber optic communication network includes a plurality of full duplex fiber optic channels and one or more auxiliary channels. In order to supervise and control the operation of the network, for both data transmission and fault/maintenance actions, each terminal station contains a processor-based subsystem capable of network monitoring, first level maintenance action, fault isolation, and remote network control and status reporting. This processor-based subsystem interfaces with each fiber optic channel, with an orderwire communication link, and with external input/output devices and surveillance equipment. Three substantially autonomous processor-based sections which are dedicated to performing specific functions within the overall network operation are employed for carrying out these separate interfacing tasks.