Audio band signal transmission system and method

An audio band signal transmission system having an audio transmission system which is arranged between a switching system and a cell switching system, and transmits an audio band signal comprising a plurality of audio band signal cells via an up line from the cell switching system to the switching system and a down line from the switching system to the cell switching system for each of a plurality of connections, and has a cell delay variation absorbing buffer for delayed-reading the audio band signal which is transmitted via the up line, comprising, for each of the plurality of connections:

• a connection identification number cell transmitting portion of the audio transmission system setting a connection identification number which is to be identified, and transmitting a control cell containing the connection identification number, which is paired with the audio band signal cell, separately from the audio band signal cell which is to be transmitted to the switching system via the up line for the connection;
• a connection identification number cell detecting portion of the audio transmission system detecting a control cell which is paired with the audio band signal cell to be transmitted from the switching system via the down line for the connection, and then detecting the connection identification number contained in the control cell;
• and
• a routine correcting portion of the audio transmission system for correcting a routine before the audio band signal cell, which is transmitted to the switching system via the up line for connection in response to a predetermined control signal, is input into the connection identification number cell transmitting portion corresponding to this connection, to thus transmit the audio band signal cell via the down line corresponding to this connection without intervention of the switching system and the cell delay variation absorbing buffer;
• wherein, when the connection identification number cell detecting portion of the connection identification number detecting portion for one of the plurality of connections detects another connection identification number of another one of the plurality of connections via the down line for the connection, the connection identification number cell detecting portion instructs the connection identification number cell detecting portion of the other connection to output the predetermined control signal.

An audio band signal transmission method of transmitting an audio band signal comprising a plurality of audio band signal cells via an up line from a cell switching system to a switching system and a down line from the switching system to the cell switching system for each of a plurality of connections by using an audio transmission system arranged between the switching system and the cell switching system, and then delayed-reading the audio band signal, which is transmitted via the up line, by using a cell delay variation absorbing buffer in the audio transmission system, comprising, for each of the plurality of connections, the steps of:

• setting a connection identification number which identifies the connection, and inserting the connection identification number into an audio band signal cell, which is to be transmitted to the switching system via the up line for the connection, by using a connection identification number inserting portion of the audio transmission system;
• detecting the connection identification number contained in the audio band signal cell, which is to be transmitted from the switching system via the down line for the connection, by using a connection identification number detecting portion of the audio transmission system;
• correcting a routine before the audio band signal cell, which is transmitted to the switching system via the up line for the connection in response to a predetermined control signal, is input into the connection identification number inserting portion corresponding to the connection by using a routine correcting portion of the audio transmission system, to thus transmit the audio band signal cell via the down line corresponding to the connection without intervention of the switching system and the cell delay variation absorbing buffer;
• and
• instructing the connection identification number detecting portion of one of the plurality of connections, which corresponds to the connection identification number, to output the predetermined control signal by the connection identification number detecting portion of the connection identification number detecting portion for another one of the plurality of connections when the connection identification number detecting portion detects the connection identification number via the down line for the connection.

An audio band signal transmission method of transmitting an audio band signal comprising a plurality of audio band signal cells via an up line from a cell switching system to a switching system and a down line from the switching system to the cell switching system for each of a plurality of connections by using an audio transmission system which is arranged between the switching system and the cell switching system, and then delayed-reading the audio band signal, which is transmitted via the up line, by using a cell delay variation absorbing buffer in the audio transmission system, comprising, for each of the plurality of connections, the steps of:

• setting a connection identification number which identifies the connection, and then transmitting a control cell containing the connection identification number, which is paired with the audio band signal cell, separately from the audio band signal cell, which is to be transmitted to the switching system via the up line for the connection, by using a connection identification number cell transmitting portion of the audio transmission system;
• detecting a control cell which is paired with the audio band signal cell to be transmitted from the switching system via the down line for the connection, and then detecting the connection identification number contained in the control cell, by using a connection identification number cell detecting portion of the audio transmission system;
• correcting a routine before the audio band signal cell, which is transmitted to the switching system via the up line for the connection in response to a predetermined control signal, is input into the connection identification number cell transmitting portion corresponding to this connection by using a routine correcting portion of the audio transmission system, to thus transmit the audio band signal cell via the down line corresponding to this the connection without intervention of the switching system and the cell delay variation absorbing buffer;
• and
• instructing the connection identification number cell detecting portion of one of the plurality of connections, which corresponds to the connection identification number, to output the predetermined control signal by the connection identification number cell detecting portion of the connection identification number detecting portion of another one of the plurality of connections when the connection identification number cell detecting portion detects the connection identification number via the down line for the connection.