JPS6230543B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to switchboard trunking systems, and more particularly to switchboard trunking systems in electronic exchanges having time division networks.

FIG. 1 is a diagram showing an example of a conventional switchboard trunk system in this type of electronic exchange. In Figure 1, a switchboard OBD operator responds to a call that arrives at the incoming trunk ICT via the switchboard trunk PST and communication paths 1 and 2 in the time division network NW, and responds to the caller's request. A call is made to the outgoing trunk OGT via communication path 3, and the called party is called. When the called party answers, it announces the incoming call, and if necessary, after conducting a three-way conversation with the calling party and the called party, the connection trunk CNT and communication path 7 in the time network NW are
and incoming trunk ICT and outgoing trunk via 8
Connect to OGT and start a conversation between the calling party and the called party. On the other hand, the supervisor at the director's stand KBD is at the switchboard.
In order to give instructions to the OBD operator regarding the exchange handling status and listening/talking requirements, communication paths 4, 5, and 6 are set up in the time-sharing network NW, and 2 is released, and the mixed trunk TWT is used to communicate with the switchboard OBD. Listen to the caller and called party. If a supervisor calls the switchboard without being overheard by the caller or called party,
When giving instructions to the OBD converter, enter the trunk
Trunk that temporarily connects ICT and outgoing trunk OGT
Change the connection to CNT.

As is clear from the above explanation, in the conventional switchboard trunk system, it is necessary to use a mixed trunk TWT for listening from the supervisor's KBD, and it is also necessary to use a mixed trunk TWT for listening to calls from the supervisor and the switchboard OBD operator. Therefore, it was necessary to change the connection to the connection trunk CNT. Additionally, digital adders have traditionally been used to implement three-party calls within the switchboard trunk PST between the calling party, the called party, and the switchboard OBD operator. Mixing using the digital adder requires digital signals with predetermined companding characteristics to be converted back into linear codes for addition, and then to have companding characteristics again after the addition, which necessitates a large number of companders. , it becomes large and uneconomical.

An object of the present invention is to eliminate the drawbacks of the conventional switchboard trunk system as described above, and to economically realize a switchboard trunk that allows listening and instructions from the supervisor's desk without using mixed trunks or connecting trunks. It's about doing.

The purpose of this is to provide a gate for extracting digital signals for each channel from a plurality of channels of the time division network in an electronic exchange having a time division network, and a gate for extracting digital signals for each channel from the plurality of channels of the time division network, and A digital-to-analog converter that converts into an analog signal for each communication path, and an analog converter that generates multiple sets of mixed analog signals by removing one communication path from each of the plurality of analog signals for each communication path output by the digital-to-analog converter and adding them. an adder, an analog-to-digital converter that converts a plurality of mixed analog signals output from the analog adder into mixed digital signals, and a plurality of mixed digital signals output from the analog-to-digital converter to the time division network. a mixing circuit consisting of a gate that sends the signal to a communication path not included in each mixed digital signal; and a shift register that extracts two communication paths from the plurality of communication paths of the time division network and stores them for each communication path. and a gate for converting the digital signals of the two communication paths outputted from the shift register into the two communication paths of the time division network and transmitting the converted signals. Ru.

An embodiment of the present invention will be described below with reference to FIGS. 2 to 5. FIG. 2 is a diagram showing a switchboard trunk system according to an embodiment of the present invention, FIG. 3 is a diagram showing an example of the configuration of the switchboard trunk shown in FIG. 2, and FIGS. 4 is a diagram illustrating control signals for each gate shown in FIG. 3. FIG. In addition,
The same reference numerals indicate the same objects throughout the figures. The switchboard trunk PST′ shown in Figure 2 is the switchboard OBD
While the operator is in a two-party or three-party conversation with the caller on the incoming trunk ICT side and the called party on the outgoing trunk OGT side, set up call path 9 within the time-sharing network NW from the supervisor's desk KBD. This allows the supervisor to directly listen to the two- or three-party calls. Furthermore, the switching trunk PST' can connect the supervisory board KBD and the switching board OBD independently of the connection between the incoming trunk ICT and the outgoing trunk OGT, so that the mixed trunk TWT and connecting trunk as shown in Fig. 1 can be connected. CNT is no longer required.
As shown in FIG. 3, the switchboard trunk PST' includes a mixing circuit MX and a two-path switching circuit EX. Communication paths 1, 3, 2 and 9 in the current time division network NW belong to each frame F of the down highway DHW as shown in FIG. The audio of
Each channel is input as digital signals a ₁ , b ₁ , c ₁ and d ₁ to the switchboard trunk PST' together with other channels belonging to the down highway DHW.
The gates GO to _G3 of the mixing circuit MX input the control signals _g0 to _g3 as shown in FIG. Digital signals a ₁ , b ₁ , for each channel corresponding to 2 and 9
Extract c ₁ and d ₁ . Digital signals _{a 1 , b 1 ,} c ₁ and
d ₁ is converted into analog signals a ₂ , b ₂ , c ₂ and d ₂ for each channel by the digital-to-analog converter DA, and transmitted to the analog adder AAD. The analog adder AAD uses four sets of adders AAD ₀ to AAD ₃ to generate an analog signal a 2 for each channel for one channel from the input analog signals a ₂ , b ₂ , c ₂ and d ₂ for each channel _. , b ₂ , c ₂ or d ₂ , analog signals for each channel for the remaining 3 channels (b ₂ , c ₂ , d ₂ ), (a ₂ , c ₂ , d ₂ ), (a ₂ , b ₂ , d ₂ ) and (a ₂ , b ₂ , c ₂ ) are respectively analog-added to generate mixed analog signals a ₃ , b ₃ , c ₃ and d ₃ .
The mixed analog signals a ₃ , b ₃ , c ₃ and d ₃ output from the analog adder AAD are converted into mixed digital signals by the analog-to-digital converter AD, respectively.
converted into a ₄ , b ₄ , c ₄ and d ₄ and gates G ₄ to
Transmitted to G ₇ . Gates G ₄ to G ₇ receive respective mixed digital signals a ₄ , b ₄ , and c 4 by inputting control signals g ₄ to g ₇ synchronized with control signals g ₀ to _{g 3} as shown in FIG. and gate d ₄ g ₁₀
Digital signals a ₅ , b ₅ , c ₅ and d ₅ are sent out for each communication path to communication paths 1, 3, 2 and 9 in each frame F of the up highway as shown in FIG. Digital signals a ₅ , b ₅ , c ₅ for each channel
and d ₅ are digital signals for each channel of the down highway DHW (b ₁ , c ₁ , d ₁ ), (a ₁ ,
c ₁ , d ₁ ), (a ₁ , b ₁ , d ₁ ) and (a ₁ , b ₁ , c ₁ ), so the caller, called party, switchboard operator, and supervisor can each listen to the calls of the other three parties. By always maintaining only the control signal _g3 at a logic value of 0, the digital signal _d1 for each channel carrying the supervisor's transmission can be blocked from being input to the mixing circuit MX, and the supervisor can only listen. I can do it.
If the supervisor then needs to speak to the switchboard operator without being overheard by the calling and called parties,
As shown in FIG. 5, the control signals g ₂ ,
g ₃ , g ₆ and g ₇ are always maintained at a logical value of 0, and a control signal g ₈ is input to gates G ₈ and G ₉ of the two-path switching circuit. The shift register SR of the two-channel exchange circuit EX stores all of the down-highway DHW digital signals a ₁ , b ₁ , c ₁ and d ₁ for channels 1, 3, 2 and 9. A digital signal is inputted via the buffer register BR, but the clock signal clk is supplied via the gate _G8 only during the period corresponding to the communication paths 2 and 9 by the control signal _g8 . and 9 digital signals c ₁ and d ₁ are alternately accumulated for each channel. Note that the digital signal for each channel has an 8-bit configuration, and the shift register SR also has an 8-stage configuration. At the end time _t1 of the communication path 2, the digital signal _c1 for each communication path is accumulated in the shift register, and the digital signal c1 for the communication path 9 is stored in the shift register.
It is held until the starting point t ₂ . From time _t2 , the digital signal _d1 for each channel of the channel 9 is stored in the shift register SR for 1 bit, and the stored digital signal _c1 for each channel is output for 1 bit. Similarly, the digital signal d ₁ for each channel held in the shift register SR until the start time t ₀ of channel 2 becomes the digital signal c ₁ for each channel from time t ₀ .
As 1 bit is accumulated, 1 bit is output. In this way, the shift register SR outputs the exchanged digital signals d ₁ and c ₁ corresponding to the communication paths 2 and 9 for each communication path. The exchanged digital signals d ₁ and c ₁ for each channel are:
It is sent to communication paths 2 and 9 of the up-highway UHW via a gate _G9 controlled by a control signal _g8 , respectively. As a result of the above, the switchboard operator and the supervisor can communicate over the phone. Mixed circuit MX on the other hand
, the control signals g ₂ , g ₃ , g ₆ and g ₇ put the gates G ₂ , G ₃ , G ₆ and G ₇ in the blocked state, so that the calls corresponding to the communication paths 1 and 3 are blocked from the down highway DHW. digital signals a ₁ and b ₁
Also, only digital signals _a5 and _b5 for each communication path corresponding to communication paths 1 and 3 are sent to the up highway UHW. Of course, the digital signal for each channel a ₅ has the digital signal b ₁ for each channel.
Since the per-channel digital signal _b5 includes only the per-channel digital signal _a1 , the calling party and the called party can communicate. Further, the calls between the calling party and the called party and the calls between the switchboard operator and the supervisor are carried out independently of each other.

As is clear from the above description, according to this embodiment, the supervisor can directly connect the supervisory board KBD to the switchboard trunk PST' and
You can listen to the response of the switchboard OBD handler to the calling and called parties connected via PST', and also communicate only with the switchboard OBD handler via the switchboard trunk PST'. During this time, the calling party and the called party can communicate independently via the switching trunk PST'. Furthermore, the switchboard trunk PST' is mainly composed of an analog adder AAD, which is smaller and more economical than when a digital adder is used.

Note that FIGS. 2 to 5 are only one embodiment of the present invention, and for example, communication path 1,
2, 3, and 9 are not limited to belonging to the same down highway DHW and up highway UHW, and may be considered to belong to multiple highways in a distributed manner, but the present invention also applies in such a case. The effect remains the same. Furthermore, the digital signal for each channel is not limited to being composed of 8 bits, and the effects of the present invention will not change even if it is composed of any other arbitrary number of bits. Furthermore, switchboard trunk
The number and type of communication paths connected to PST' are not limited to those shown in the drawings, and many other modifications may be considered, but the effects of the present invention will not change in any case.

As described above, according to the present invention, in an electronic exchange having a time-sharing network, it becomes possible to directly interrupt connection to a connection via a switchboard trunk, eliminate the need for interrupt connection equipment such as a mixed trunk, and A plurality of sets of independent two-party communication routes are configured within the system, and independent communication equipment such as connection trunks is not required. Furthermore, since multiparty calls via the switching trunk are realized by adding analog signals, the switching trunk can be made smaller and more economical.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a conventional switchboard trunk system, FIG. 2 is a diagram showing a switchboard trunk system according to an embodiment of the present invention, and FIG. 3 is a configuration of the switchboard trunk shown in FIG. 2. FIG. 4 is a diagram illustrating control signals for each gate of the mixing circuit shown in FIG. 3; FIG. 5 is a diagram illustrating control signals for the gates of the two-channel switching circuit shown in FIG. 3. This is a diagram. In the figure, NW is a time division network, 1 to 9 are communication paths, ICT is an incoming trunk, OGT is an outgoing trunk, CNT is a connecting trunk, PST and
PST′ is a switching trunk, TWT is a mixed trunk,
OBD is a switching board, KBD is a supervisory board, MX is a mixed circuit,
EX is a 2-path switching circuit, G ₀ to G ₁₀ are gates,
DA is a digital to analog converter, AD is an analog to digital converter, AAD is an analog adder,
AA ₀ to AAD ₃ are adders, BR is a buffer register, SR is a shift register, DHW is a down highway, UHW is an up highway, a ₁ , b ₁ , c ₁ , d ₁ ,
a ₅ , b ₅ , c ₅ and d ₅ are digital signals for each channel,
a ₂ , b ₂ , c ₂ and d ₂ are analog signals for each channel,
a ₃ , b ₃ , c ₃ and d ₃ are mixed analog signals, a ₄ ,
b ₄ , c ₄ and d ₄ are mixed digital signals, g ₀ to g ₈
is a control signal, clk is a clock signal, F is a frame, and t ₀ to t ₃ are time points.

Claims (1)

[Claims] 1. In an electronic exchange having a time-division network, a gate extracts a digital signal for each communication path from a plurality of communication paths of the time-division network, and a gate extracts digital signals for each communication path from a plurality of communication paths of the time-division network, and extracts digital signals for each communication path from the plurality of communication paths output from the gate. a digital-to-analog converter for converting into an analog signal; an analog adder for generating a plurality of sets of mixed analog signals obtained by subtracting one call route from each of the plurality of analog signals output by the digital-to-analog converter and adding them together; an analog-digital converter that converts a plurality of mixed analog signals output from the analog adder into mixed digital signals, and converts the plurality of mixed digital signals output from the analog-digital converter into each mixed digital signal of the time division network; a mixing circuit consisting of a gate for sending out signals to communication paths not included in the time division network, and a shift register for extracting digital signals of two communication paths from the plurality of communication paths of the time division network and accumulating them for each call; It is characterized by comprising a two-channel exchange circuit comprising a gate for exchanging digital signals of the two channels outputted from the shift register to the two channels of the time division network and sending them out. Switchboard trunk system.