SUBMARINE CABLE BRANCHING UNITS WITH FIBER PAIR SWITCHING
FIG2 is a functional block diagram of one example of a fiber pair switching branching unit consistent with the present disclosure
FIG2 illustrates one example of a branching configuration 163a consistent with the present disclosure. The illustrated example branching configuration 163a includes a FPS-BU 130a and an optional WMU 150. The FPS-BU 130a includes an optical bypass switch portion 202, a controllable optical routing device (RORD) 204, and a controller 206. The branching configuration 163a is coupled between a west portion of an optical cable 112, an east portion of an optical cable 112 and a branch cable 162. For simplicity and east of description, the terms west and east, and other directional or positional terms, may be used herein to describe the general relative orientation or position of components or elements of a system. These terms are not limited to the specific directions, e.g. west or east, referenced but are instead used to describe relative orientation, e.g. opposite sides or directions of travel. Each of the couplers couples a portion of the east bound signal to an input of the drop WSS 418. The output of the drop WSS 418 is coupled to the west side branch cable drop fiber 406. Each of the WSSs is coupled to an output of the splitter 420. The input to the splitter 420 is coupled to the west side branch cable add fiber 408. The state of the outputs of the WSSs may each be selectively controlled by a controller, e.g. controller 204 (FIG2) in response to a remote command signal. The east side portion of the FPS-BU 103c includes an optical coupler coupled to each of the fibers 416-1...416-N carrying west bound signals, a WSSs coupled to each of the fibers 414-1...414-N carrying east bounds signals, a NxM drop WSS 422 and an NxM add optical splitter/coupler 424. Each of the couplers couples a portion of the east bound signal to an input of the drop WSS 422. The output of the drop WSS 422 is coupled to the west side branch cable drop fiber 412. Each of the WSSs is coupled to an output of the splitter 424. The input to the splitter 424 is coupled to the west side branch cable add fiber 410. The state of the outputs of the WSSs may each be selectively controlled by the controller, e.g. controller 204 (FIG2) in response to a remote command signal.
block diagram
202
bypass switch portion
218
west side fiber pair
220
east side fiber pair
208
port
206
controller
204
RORD
222
branch cable. One fiber
228
other fiber
226
One fiber
2
N is
162
branch cable branch cables
112
cable
224
other fiber
150
WMU
['1. An optical communication system comprising: a trunk terminal configured to provide trunk signals on a plurality of fiber pairs of a trunk cable; a branch terminal configured to provide a branch add signal on a branch cable; and a fiber pair switching branching unit coupled to the trunk cable and the branch cable for receiving the trunk signals and the branch add signal, the branching unit comprising: at least a first optical routing device coupled to the trunk cable and configured to receive the trunk signals from each of the plurality of fiber pairs, the first optical routing device being controllable to couple signals from selected one of the plurality of fiber pairs to a drop fiber of the branch cable; and at least a second optical routing device coupled to the branch cable and configured to receive the branch add signal from the branch cable, the second optical routing device being controllable to couple the branch add signal to a fiber of one of the plurality of fiber pairs.', '3. The optical communication system of claim 1, wherein the second optical routing device is coupled to the branch cable through an associated optical splitter, wherein the optical splitter has an input port coupled to the branch cable to receive the branch add signal and a plurality of output ports, one of the plurality of output ports being coupled to the second optical routing device; wherein a second one of the output ports is coupled to a third optical routing device, the third wavelength device being controllable to couple the branch add signal to separate fiber of one of the plurality of fiber pairs.']