Multistage capacitive far end crosstalk compensation arrangement

A telecommunications jack for use in a twisted pair system, the jack comprising:

• a housing defining a port for receiving a plug;
• a plurality of contact springs adapted to make electrical contact with the plug when the plug is inserted into the port of the housing;
• a plurality of wire termination contacts for terminating wires to the jack;
• a circuit board including conductive tracks that electrically connect the contact springs to the wire termination contacts;
• and
• a crosstalk compensation arrangement that provides crosstalk compensation between selected tracks of the circuit board, the crosstalk compensation arrangement including a first zone of compensation a first time delay away from the capacitive coupling of the plug and a second zone of compensation at an second time delay from the first zone of compensation, the second zone of compensation including two capacitive elements spaced at different time delays from the first zone of compensation to optimize far end crosstalk and having an average time delay that optimizes near end crosstalk.

A crosstalk compensation system within a telecommunications jack, the system comprising:

• a circuit board;
• a plurality of contact springs mounted on the circuit board, the contact springs including first, second, third, fourth, fifth, sixth, seventh and eighth consecutively arranged contact springs;
• a plurality of wire termination contacts mounted on the circuit board, the wire termination contents including first, second, third, fourth, fifth, sixth, seventh and eighth wire termination contacts for terminating wires to the jack;
• a plurality of tracks on the circuit board, the tracks including first, second, third, fourth, fifth, sixth, seventh and eighth tracks that respectively electrically connect the first, second, third, fourth, fifth, sixth, seventh and eighth contact springs to the first, second, third, fourth, fifth, sixth, seventh and eighth wire termination contacts;
• a crosstalk compensation arrangement that provides crosstalk compensation between the tracks of the circuit board, the crosstalk compensation arrangement including a first zone of compensation a first time delay away from the contact springs and a second zone of compensation at an second time delay from the first zone of compensation, the second zone of compensation including two capacitive elements spaced at different time delays from the first capacitive coupling to compensate for far end crosstalk and having an average time delay that that optimizes near end crosstalk.

A method for determining the positions of first and second zones of crosstalk compensation in a jack, the first and second zones of crosstalk compensation being adapted to compensate for undesired crosstalk caused by an undesired capacitive coupling located at a plug inserted within the jack, the first zone of crosstalk compensation including a first capacitive coupling positioned a first time delay away from the undesired capacitive coupling of the plug, the first capacitive coupling having a greater magnitude and an opposite polarity as compared to the undesired capacitive coupling of the plug, the second zone of crosstalk compensation including a second capacitive coupling having two capacitive elements positioned, on average, a second time delay away from the first capacitive coupling, the second capacitive coupling having generally the same magnitude but an opposite polarity as compared to the first capacitive coupling, the method comprising:

• positioning the first and second capacitive couplings in initial positions in which the first and second time delays are generally equal to one another;
• adjusting the position of the second capacitive coupling from the initial position to an adjusted position to provide improved near end crosstalk compensation;
• adjusting the position of the first and second capacitive elements to different lengths to provide improved far end crosstalk compensation while maintaining the adjusted position of the second capacitive coupling as the average position of the first and second capacitive elements.

A method of designing a crosstalk compensation system for a telecommunications jack, the method comprising:

• positioning a first zone of crosstalk compensation across at least a first wire pair and a second wire pair on a circuit board within a telecommunications jack, the first wire pair including first and second wires, and the second wire pair including third and fourth wires, the first zone of crosstalk compensation placed at a first distance from contact springs associated with the first wire pair and the second wire pair;
• positioning a second zone of crosstalk compensation across the at least first and second wire pairs at a second distance from the first zone of crosstalk compensation, the second zone of crosstalk compensation including a first capacitive coupling between the first and third wires and a second capacitive coupling between the second and fourth wires;
• altering the position of the capacitive couplings to establish a distance between the first capacitive coupling and the second capacitive coupling while maintaining the second distance as an average distance from the first zone of crosstalk compensation;
• wherein altering the position of the capacitive couplings provides improved far end crosstalk compensation.