Buffering speech signals in a TASI system

A method of buffering speech signals in a TASI system in which speech signals from a plurality of channels are interpolated for transmission via a lesser plurality of transmission facilities, comprising the steps of:

• providing a buffer comprising storage packets each for storing a plurality of speech signals of a channel;
• determining, for each channel, when the channel has become active and when the channel has become inactive;
• assigning packets of the buffer to each active channel as required for the storage of signals of the channel, and storing the signals of the channel sequentially in said packets until it is determined that the channel has become inactive;
• in response to determination that a channel has become active, assigning the channel to a transmission facility for transmission of signals of the channel via the facility;
• in response to the assignment of a channel to a facility, reading the signals of the channel sequentially from the packets of the buffer assigned to the channel, for transmission via the facility;
• and
• de-assigning the packets of the buffer from the channels in response to reading of the signals of the channels therefrom.

A method of buffering speech signals in a TASI system, comprising:

• assigning a respective storage packet of a buffer to each channel having signals to be buffered;
• storing signals of the channels in the assigned packets;
• in response to each assignment of a packet to a channel, providing another, back-up, packet for assignment to the channel;
• assigning the back-up packet to the channel when another packet is required for continued storage of speech signals of the channel;
• in response to assignment of a transmission facility to a channel for transmission of signals of the channel, reading the signals of the channel from the packets assigned to the channel for transmission via the facility;
• and
• de-assigning the packets from the channels in response to reading of the signals of the channels therefrom.

A TASI system in which speech signals from a plurality of channels are interpolated for transmission via a lesser plurality of transmission facilities, said system comprising:

• a buffer comprising storage packets each for storing a plurality of speech signals of a channel;
• detecting means for determining, for each channel, when the channel has become active and when the channel has become inactive;
• means for assigning packets of the buffer to each active channel as required for the storage of speech signals of the channel, and for storing the speech signals of the channel sequentially in said packets until the channel has become inactive;
• means responsive to detection that a channel has become active for assigning the channel to a transmission facility for the transmission of speech signals of the channel via the facility, and for transmitting information representing the channel-to-facility assignment;
• and
• means responsive to the assignment of a channel to a facility for reading the speech signals of the channel sequentially from the packets of the buffer assigned to the channel and for transmitting them via the facility.

A TASI system in which speech signals from a plurality of channels are interpolated for transmission via a lesser plurality of transmission facilities, said system comprising:

• detecting means for detecting, for each off-hook channel, whether the channel is active or inactive;
• a buffer comprising a substantially greater number of storage packets than there are channels, each storage packet being capable of storing all of the signals of one channel which occur during a predetermined period;
• means for storing the signals of each channel which is inactive in a respective packet of the buffer, said signals being stored sequentially and cyclically in said packet;
• means responsive to the detecting means detecting that a channel which has been inactive has become active for producing an address which identifies a location in said respective packet at which a signal of the channel has been stored;
• for continuing to store signals of the channel sequentially in said respective packet until said location is reached, and for subsequently storing the signals of the channel sequentially in further packets of the buffer;
• means responsive to the detecting means detecting that a channel which has been active has become inactive for storing an end-of-record signal sequentially following the last signal of the channel stored in said packets;
• means responsive to the detection that the channel has become active for assigning the channel to a transmission facility for transmission of signals of the channel via the facility, and for transmitting information representing the channel-to-facility assignment;
• means responsive to the assignment of the channel to the facility for reading the stored signals of the channel sequentially from the respective packets of the buffer, commencing from said location, and for transmitting them via the facility;
• and
• means for detecting the end-of-record signal in the signals read from the buffer and for terminating the reading of signals from the buffer and the transmission of said signals via the facility in response to detection of the end-of-record signal.