Distributed passive optical networks

Abstract

A passive optical network includes one or more multi-service terminals each having a housing and a plurality of ruggedized plug-receiving distribution ports accessible from outside the housing. The multi-service terminals also each include an optical power splitter or wave division multiplexer for splitting an optical signal and directing the split signal to the plug-receiving distribution ports. Some of the multi-service terminals provide a different power split ratio from others of the multi-service terminals.

1 . A multi-service terminal comprising:
 a housing defining an interior region;   a plurality of ruggedized fiber optic adapters mounted on the housing, the ruggedized fiber optic adapters including outer plug-receiving ports accessible from outside the housing; and   an optical splitting arrangement within the interior of the housing, the optical splitting arrangement providing a first optical split that splits an input optical signal line into first and second signal lines, the first signal line including a connectorized pigtail that plugs into an inner port of one of the ruggedized fiber optic adapters, the second signal line being further split into a plurality of additional signal lines including connectorized pigtails that plug into inner ports of the ruggedized fiber optic adapters.   
     
     
         2 . A system including the multi-service terminal of  claim 1 , further comprising a second multi-service terminal that receives a signal from the first signal line of the first multi-service terminal and splits the signal into a plurality of signal lines routed to ruggedized fiber optic adapters of the second multi-service terminal. 
     
     
         3 . The multi-service terminal of  claim 1 , further comprising a ruggedized input fiber optic adapter mounted to the housing, the input fiber optic adapter having an outer port for receiving a fiber optic connector of a feeder cable and an inner port that receives a fiber optic connector terminating an end of the input optical signal line. 
     
     
         4 . A passive optical network comprising:
 a feeder fiber optic cable;   a first multi-service terminal coupled to the feeder fiber optic cable, the multi-service terminal having a housing and a plurality of ruggedized fiber optic adapters mounted on the housing, the ruggedized fiber optic adapters including outer plug-receiving distribution ports accessible from outside the housing, the multi-service terminal including a first optical splitter for splitting an optical signal from the feeder fiber optic cable into a plurality of signals routed through separate connectorized pigtails plugged into inner ports of the ruggedized fiber optic adapters, the first optical splitter having a first split ratio;   a distribution fiber optic cable having an connectorized end received within one of the distribution ports of the first multi-service terminal;   a second multi-service terminal coupled to the distribution fiber optic cable, the multi-service terminal having a housing and a plurality of ruggedized fiber optic adapters mounted on the housing, the ruggedized fiber optic adapters including outer plug-receiving distribution ports accessible from outside the housing, the multi-service terminal including a second optical splitter for splitting an optical signal carried from the first multi-serviced terminal to the second multi-service terminal by the distribution fiber optic cable into a plurality of signals routed through separate connectorized pigtails plugged into inner ports of the ruggedized fiber optic adapters of the second multi-service terminal, the second optical splitter having a second split ratio that is different from the split ratio of the first splitter.   
     
     
         5 . The passive optical network of  claim 4 , wherein the feeder fiber optic cable connects to the first multi-service terminal with a plug and play connection, and wherein the distribution fiber optic cable connects to the second multi-service terminal with a plug and play connection. 
     
     
         6 . The passive optical network of  claim 4 , wherein the first split ratio is smaller than the second split ratio. 
     
     
         7 . A method for upgrading the passive optical network of  claim 4 , wherein the first and second splitters are optical power splitters, and wherein the method comprises replacing the first splitter with a wavelength division multi-plexer. 
     
     
         8 . The method of  claim 7 , wherein the first splitter is replaced by replacing the first multi-service terminal with an upgrade multi-service terminal including the wavelength division multi-plexer. 
     
     
         9 . The method of  claim 8 , wherein the first multi-service terminal and the upgrade multi-service terminal connect to the feeder fiber optical cable with a plug and play connection. 
     
     
         10 . A method for upgrading the passive optical network of  claim 4 , wherein the first and second splitters are optical power splitters, and wherein the method comprises replacing the second splitter with a wavelength division multi-plexer. 
     
     
         11 . The method of  claim 10 , wherein the second splitter is replaced by replacing the second multi-service terminal with an upgrade multi-service terminal including the wavelength division multi-plexer. 
     
     
         12 . The method of  claim 11 , wherein the second multi-service terminal and the upgrade multi-service terminal connect to the distribution fiber optical cable with a plug and play connection.