Trunk circuit traffic analyzer

A traffic analyzer in combination with a group of trunk circuits having transmission and reception lines including a bidirectional speech path and a supervisory signalling path connecting two telephone exchanges, each telephone exchange comprising:

• decimal code signalling means for conveying decimal code signals over said supervisory signalling path of each trunk circuit;
• multifrequency code signalling means for feeding said bidirectional speech path of said trunk circuits with code speech digital signals;
• and;
• said decimal code signals and multifrequency signalling code digits providing pluralities of decimal signalling code signal sequences and multifrequency signalling code digit sequences;
• the sequences of decimal code signals being composed of different signals unambiguously defining certain phases of a telephone call and comprising a signalling code change signal and the sequences of multifrequency code digits being catenated sequences defining certain other phases of a telephone call and being composed of a number of multifrequency code digits variable according to the phases they define;
• said traffic analyzer comprising means for cyclically sampling said decimal signalling code signals;
• means for connecting said sampling means to said transmission and reception lines of said trunk circuits;
• means controlled by said sampling means for sensing said signalling code change signal;
• a number of multifrequency signalling receivers which are smaller than the number of trunk circuits in said group;
• said receivers detecting said multifrequency signalling code digits;
• a switching network having inputs connected to said bidirectional speech path of each said trunk circuit and outputs connected to said multifrequency signalling receivers;
• means controlled by said signalling code change signal sensing means for selectively operating said switching network, thereby connecting a multifrequency signalling receiver to a trunk circuit;
• a memory having recorded therein at addresses formed by the digits of a given multifrequency code digit sequence which are detected by said multifrequency signalling receiver, the number of digits of a following multifrequency code digit sequence catenated with said given sequence;
• a counter;
• means for transferring from said memory to said counter said number of digits of said following sequence;
• means for decrementing said counter by the multifrequency digits detected by said connected multifrequency signalling receiver and for transmitting said addresses to said memory which are connected to said multifrequency signalling receiver via said switching network;
• means for sensing the count zero in said counter and means controlled by said count zero sensing means for disconnecting said connected multifrequency receiver.

A traffic analyzer in combination with a group of trunk circuits having transmission and reception lines including a bidirectional speech path and a supervisory signalling path connecting an originating exchange to a terminating exchange, each telephone exchange comprising:

• decimal code signalling means for conveying decimal code signals over said supervisory signalling path of each trunk circuit;
• multifrequency code signalling means for feeding said bidirectional speech path of said trunk circuits with code speech digital signals;
• and;
• said decimal code signals and multifrequency signalling code digits providing pluralities of decimal signalling code signal sequences and multifrequency signalling code digit sequences;
• the sequences of decimal code signals being composed of different signals comprising a signalling code change signal and unambiguously defining the phase of a telephone call including seizing of the terminating exchange by the originating exchange, called subscriber answering and call release and the sequence of multifrequency code digits being catenated sequences defining other phases of a telephone call including order of dialling given from said terminating exchange to said originating exchange and dialling in said originating exchange, and being composed of a number of multifrequency code digits variable according to the phases they define;
• said traffic analyzer comprising means for cyclically sampling said decimal signalling code signals;
• means for connecting said sampling means to said transmission and reception lines of said trunk circuits;
• means controlled by said sampling means for sensing said signalling code change signal;
• a number of multifrequency signalling receivers smaller than the number of circuits in said group;
• said receivers detecting said multifrequency signalling code digits;
• means controlled by said signalling code change signal sensing means for connecting a multifrequency signalling receiver to said bidirectional speech path of a trunk circuit, a memory having recorded therein at addresses formed by the digits of a given frequency code digit sequence which are detected by said multifrequency signalling receiver, the number of digits of a following multifrequency code digit sequence catenated with said given sequence,
• a counter;
• means for transferring from said memory to said counter said number of digits of said following sequence;
• means for decrementing said counter by the multifrequency digits detected by said connected multifrequency signalling receiver and for transmitting said addresses to said memory which are connected to said multifrequency signalling receivers;
• means for sensing the count zero in said counter and means controlled by said count zero sensing means for disconnecting said connected multifrequency signalling receiver.