Signal processing apparatuses and methods for identifying cable connections between ports

A signal processing method including:

• generating a first test signal;
• coupling, using a first coupling unit, the first test signal into a first one of a plurality of cable lines by non-contact coupling with the conductors of the first cable line such that the first test signal propagates along the first cable line between at least two conductors in the first cable line;
• coupling, using a second coupling unit, a second test signal out from the second cable line by non-contact coupling with the conductors of the second cable line;
• and
• analyzing one or more characteristics of the second test signal to determine, based on the one or more analyzed characteristics, which of the following conditions, if any, is true:
• (i) the second test signal is a direct signal that has propagated directly from the first coupling unit to the second coupling unit via a single cable line to which the first and second coupling units are coupled;
• (ii) the second test signal is a crosstalk signal that has propagated indirectly from the first coupling unit to the second coupling unit via one or more coupling paths between different cable lines to which the first and second coupling units are respectively coupled.

A signal processing apparatus for use with a plurality of cable lines, the signal processing apparatus having:

• a signal generating unit configured to generate a first test signal;
• a plurality of first coupling units, each first coupling unit being configured to couple to a respective first one of the plurality of cable lines and to couple a respective first test signal generated by the signal generating unit into the respective first cable line by non-contact coupling with the conductors of the first cable line such that the respective first test signal propagates along the respective first cable line between at least two conductors in the respective first cable line;
• a plurality of second coupling units, each second coupling unit being configured to couple to a respective second one of the plurality of cable lines and, if a respective second test signal is present in the respective second cable line, to couple the respective second test signal out from the respective second cable line by non-contact coupling with the conductors of the second cable line;
• a signal processing unit configured to, if any one or more of the second coupling units couples out a respective second test signal, analyze one or more characteristics of the or each respective second test signal to determine, for at least one respective second test signal, based on the one or more analyzed characteristics, which of the following conditions, if any, is true:
• (i) the respective second test signal is a direct signal that has propagated directly from a first coupling unit to a second coupling unit via a single cable line to which the first and second coupling units are coupled;
• (ii) the respective second test signal is a crosstalk signal that has propagated indirectly from a first coupling unit to the second coupling unit via one or more coupling paths between different cable lines to which the first and second coupling units are respectively coupled;
• wherein the signal processing unit is configured to, if it determines that a second test signal coupled out by a second coupling unit is a direct signal that has propagated directly from a first coupling unit to the second coupling unit via a single cable line to which the first and second coupling units are coupled, identify an interconnection between a first port associated with that first coupling unit and a second port associated with that second coupling unit;
• wherein each first coupling unit includes:
• first and second electrodes arranged to produce an electric field therebetween to couple a voltage signal into a twisted pair cable by non-contact coupling with twisted pairs in the twisted pair cable so that the voltage signal propagates along the twisted pair cable between at least two of the twisted pairs;
• and
• electrical isolation means arranged to electrically isolate the electrodes from the signal generating unit;
• wherein each second coupling unit includes:
• first and second electrodes arranged to couple a voltage signal out from a twisted pair cable by non-contact coupling with at least two of the twisted pairs in the twisted pair cable between which the voltage signal has propagated;
• and
• electrical isolation means arranged to electrically isolate the electrodes from the signal processing unit.