Line sharing multipoint pots splitter with intelligent termination

Abstract

The present invention provides for a system and method for blocking leakage signals and uncoupling connections in a communication system. A leakage signal (LS) blocking splitter employs a high-pass filter which effectively blocks the lower frequency leakage signal. A detect and terminate function detects service on the communication connection to which each one of the LS filters are coupled to. The detect and terminate function detects service on the communication connection to ensure that each LS blocking splitter is coupled to an in-service communication connection. If the communication connection becomes out-of-service, the detect and terminate functions automatically uncouple the respective LS filter from the communication connections so that the LS filter cannot introduce undesirable harmonics into the communication system. In an alternative embodiment, the detect and terminate function may insert an impedance matching element in addition to uncoupling the LS filter.

1 . A system for coupling a plurality of subscriber loops to a data transceiver, comprising:
 a transceiver having an output connection coupled to a plurality of subscriber loops, the transceiver configured to communicate at least one data signal to a digital device coupled to one of the subscriber loops; and   an eavesdropping prevention (EP) system, the EP system coupled between a first subscriber loop and the transceiver, the EP system configured to prevent propagation of a leakage signal from the first subscriber loop to a second subscriber loop.   
     
     
         2 . The system of  claim 1 , wherein the transceiver is configured to communicate using time division multiplexing to the digital device and a second digital device, the second digital device coupled to another subscriber loop. 
     
     
         3 . The system of  claim 1 , wherein the transceiver is configured to communicate using time division multiplexing to the digital device and a plurality of other digital devices, the other digital devices coupled to other subscriber loops. 
     
     
         4 . The system of  claim 1 , wherein at least one EP system comprises a leakage signal (LS) blocking splitter. 
     
     
         5 . The system of  claim 4 , wherein the LS blocking splitter comprises a leakage signal filter. 
     
     
         6 . The system of  claim 1 , wherein at least one EP system comprises an amplifier-based coupler having a low impedance characteristic corresponding to the leakage signal. 
     
     
         7 . The system of  claim 6 , wherein the EP system further comprises a line coupler configured to couple the amplifier-based coupler to a subscriber loop. 
     
     
         8 . The system of  claim 1 , wherein at least one EP system comprises a multipoint controllable line selection system configured to select one of the plurality of subscriber loops. 
     
     
         9 . A system, comprising:
 means for coupling a transceiver to a plurality of subscriber loops, the transceiver configured to communicate at least one data signal to a digital device coupled to one of the subscriber loops; and   means for preventing the detection of a leakage signal from a first subscriber loop on another subscriber loop.   
     
     
         10 . The system of  claim 9 , wherein the means for preventing detection of a leakage signal comprises means for preventing the propagation of the leakage signal from the first subscriber loop to the another subscriber loop. 
     
     
         11 . The system of  claim 10 , wherein the means for preventing the propagation of the leakage signal comprises a leakage signal (LS) blocking splitter. 
     
     
         12 . The system of  claim 9 , wherein the means for preventing detection of a leakage signal comprises an amplifier-based coupler having a low impedance characteristic corresponding to the leakage signal. 
     
     
         13 . The system of  claim 12 , wherein the means for preventing detection of a leakage signal further comprises a plurality of line couplers, each line coupler configured to couple the amplifier-based coupler to a different subscriber loop. 
     
     
         14 . The system of  claim 9 , wherein the means for preventing detection of a leakage signal comprises means for multipoint controller line selection of one of the plurality of subscriber loops. 
     
     
         15 . The system of  claim 9 , wherein the means for preventing detection of a leakage signal comprises means for masking the leakage signal. 
     
     
         16 . The system of  claim 15 , wherein the means for masking the leakage signal comprises a mask signal generator. 
     
     
         17 . The system of  claim 15 , wherein the means for masking the leakage signal masks a portion of a frequency range of the leakage signal. 
     
     
         18 . The system of  claim 9 , wherein the means for preventing detection of a leakage signal is coupled between the first subscriber loop and the transceiver. 
     
     
         19 . A method implemented at a central office comprising the steps of:
 sensing a leakage signal from a first subscriber loop; and   preventing detection of the leakage signal on a second subscriber.   
     
     
         20 . The method of  claim 19 , wherein preventing the detection of the leakage signal comprises the steps of:
 generating a mask signal that encompasses at least a portion of a frequency range of the leakage signal; and   transmitting the mask signal onto the second subscriber loop.   
     
     
         21 . The method of  claim 20 , wherein preventing the detection of the leakage signal further comprises the steps of:
 determining the amplitude of the leakage signal; and   adjusting the amplitude of the mask signal in response to the amplitude of the leakage signal.   
     
     
         22 . The method of  claim 20 , wherein the mask signal has a predetermined fixed amplitude. 
     
     
         23 . The method of  claim 20 , wherein the mask signal has a predetermined fixed frequency range. 
     
     
         24 . The system of  claim 5 , wherein the LS blocking splitter further comprises a receive line selector. 
     
     
         25 . The system of  claim 6 , wherein the low impedance characteristic is substantially zero. 
     
     
         26 . The system of  claim 6 , wherein the amplifier-based coupler comprises a negative feedback amplifier.