Pulse width modulated self-clocking and self-synchronizing data transmission and method for a telephonic communication network switching system

In a telecommunications network of transceiving informational sources, the improvement being a switching interface system for communication between said sources, comprising:

• a control unit connected with some of said sources including
• means for encoding information from some of said sources in a serial, pulse width binary format, and
• means for serially transmitting pulse width binary encoded pulses of said encoding information at a preselected transmission bit rate;
• and
• a network termination unit connected with other ones of said sources including
• means responsive to the serially transmitted, pulse width binary encoded pulses to extract therefrom a clock signal including means for generating said clock signal at a frequency which is a preselected multiple of the transmission bit rate, and
• means responsive to said clock signal and said serially transmitted pulse width binary encoded pulses for synchronous decoding of the serially transmitted, pulse width binary encoded pulses for provision to said other ones of said sources connected with the network termination unit.

In a telecommunications network of transceiving informational sources, the improvement being a switching interface system for communication between said sources, comprising:

• a control unit connected with some of said sources including
• means for encoding information from some of said sources in a serial, pulse width binary format,
• means for serially transmitting pulse width binary encoded pulses of said encoding information at a preselected transmission bit rate, and
• means for periodically inserting phase synchronization pulses into said serially transmitted pulse width binary encoded pulses to provide phase synchronizational information;
• and
• a network termination unit connected with other ones of said sources including
• means responsive to the serially transmitted, pulse width binary encoded pulses to extract therefrom a clock signal, and
• means responsive to said clock signal and said serially transmitted pulse width binary encoded pulses for synchronous decoding of the serially transmitted, pulse width binary encoded pulses for provision to said other ones of said sources connected with the network termination unit,
• means responsive to said phase synchronization pulses to transmit data to said control unit in phase synchronism with said pulse width binary encoding data pulses at said preselected transmission bit rate including
• a phase synchronization acquisition circuit for generating a synchronization control signal, and
• means responsive to the synchronization control signal for controlling the synchronous transmission of data to said control unit to maintain the transmission of data to the control unit in synchronization with the synchronization pulses generated thereby.

In a telecommunications network of transceiving informational sources, the improvement being a switching interface system for communication between said sources, comprising:

• a control unit connected with some of said sources including
• means for encoding information from some of said sources in a serial, pulse width binary format,
• means for serially transmitting pulse width binary encoded pulses of said encoding information at a preselected transmission bit rate, and
• means for periodically inserting phase synchronization pulses into said serially transmitted pulse width binary encoded pulses to provide phase synchronizational information thereto;
• and
• a network termination unit connected with other ones of said sources including
• means responsive to the serially transmitted, pulse width binary encoded pulses to extract therefrom a clock signal,
• means responsive to said clock signal and said serially transmitted pulse width binary encoded pulses for synchronous decoding of the serially transmitted, pulse width binary encoded pulses for provision to said other ones of said sources connected with the network termination unit,
• means responsive to said phase synchronization pulses to transmit data to said control unit in phase synchronism with said pulse width binary encoding data pulses at said preselected transmission bit rate,
• including
• a counter triggered by said clock signal,
• means responsive to said counter for identifying the time division multiplexing channels of the telecommunication network, and
• means responsive to said synchronization control signal for maintaining said counter in phase synchronization with said phase synchronization pulses of said control unit.

In a telecommunications network of transceiving informational sources, the improvement being a switching interface system for communication between said sources, comprising:

• a control unit connected with some of said sources including
• means for encoding information from said sources as a series of data pulses in a serial pulse width binary format,
• means for generating pulse width encoded synchronization pulses, and
• means for transmitting said series of data pulses and pulse width encoded synchronization pulses together on a time division multiplexing basis at a preselected bit rate;
• and
• a network termination unit connected with other ones of said sources including
• means responsive to at least said pulse width encoded synchronization pulses to derive a clock signal,
• means responsive to said clock signal and said serially transmitted pulse width binary encoded pulses for synchronous decoding of the series of pulse width encoded data pulses for connection to said other ones of the sources connected with the network termination unit, and
• means responsive to said pulse width encoded synchronization pulses to control synchronization of the synchronous decoding means of the network termination unit with the encoding means of the control unit.

In a telecommunications network of transceiving informational sources, the improvement being a switching interface system for communication between said sources, comprising:

• a control unit connected with some of said sources including
• means for encoding information from said sources as a series of data pulses,
• means for generating pulse width encoded synchronization pulses, and
• means for transmitting said series of data pulses and pulse width encoded synchronization pulses together on a time division multiplexing basis at a preselected bit rate;
• and
• a network termination unit connected with other ones of said sources including
• means responsive to at least said pulse width encoded synchronization pulses to derive a clock signal,
• means responsive to said clock signal and said serially transmitted information encoded for synchronous decoding of the series of data pulses for connection to said other ones of the sources connected with the network termination unit,
• means for transmitting data from the other ones of the sources connected thereto to the control unit which includes means responsive to said synchronization pulses for maintaining said data transmitted to the control unit in phase synchronization with the pulse width encoded synchronization pulses from the control unit including
• a phase synchronization acquisition circuit responsive to the synchronization pulses received at the network termination unit to develop a synchronization control signal for controlling the phase synchronization of the encoding means, and
• means responsive to said pulse width encoded synchronization pulses to control synchronization of the synchronous decoding means of the network termination unit with the encoding means of the control unit.

In a telecommunications network of informational sources, the improvement being a switching interface system for communication between said sources, comprising:

• a control unit connected with some of said sources including
• means for binarily encoding information from a series of data pulses,
• means for decoding information received in a series of data pulses,
• means for generating a series of synchronization pulses of a preselected width differing from those of the data pulses, and
• means for transmitting said encoded information and said synchronization pulses together at a preselected bit rate;
• and
• a network termination unit connected with other ones of said sources including
• means responsive to at least said synchronization pulses to derive a clock signal,
• means responsive to said clock signal and said serially transmitted binary encoded pulses for synchronous encoding and transmission of information from said other one of the sources to the control unit, and
• means responsive to said synchronization pulses to control phase synchronization of the encoding and transmitting means of said network termination unit with said decoding means of the control unit.

In a telecommunications network or informational sources, the improvement being a switching interface system for communication between said sources, comprising:

• a control unit connected with some of said sources including
• means for encoding information from a series of data pulses,
• means for decoding information received in a series of data pulses,
• means for generating synchronization pulses of a preselected width differing from those of the data pulses, and
• means for transmitting said encoded information and said synchronization pulses together at a preselected bit rate;
• and
• a network termination unit connected with other ones of said sources including
• means responsive to at least said synchronization pulses to derive a clock signal,
• means responsive to said clock signal and said serially transmitted information encoded data pulses for synchronous encoding and transmission of information from said other one of the sources to the control unit,
• means responsive to said synchronization pulses to control phase synchronization of the encoding and transmitting means of said network termination unit with said decoding means of the control unit,
• means responsive to the synchronization pulses from the control unit for detecting phase nonsynchronization with said control unit, and
• means responsive to said nonsynchronization detecting means to alter the timing of the encoding and transmitting means to eliminate the condition of nonsynchronization.

In a telecommunications network of informational sources, the improvement being a switching interface system for communication between said sources, comprising:

• a control unit connected with some of said sources including
• means for encoding information from a series of data pulses,
• means for decoding information received in a series of data pulses,
• means for generating synchronization pulses of a preselected width differing from those of the data pulses, and
• means for transmitting said encoded information and said synchronization pulses together at a preselected bit rate;
• and
• a network termination unit connected with other ones of said sources including
• means responsive to at least said synchronization pulses to derive a clock signal,
• means responsive to said clock signal and said serially transmitted information encoded data pulses for synchronous encoding and transmission of information from said other one of the sources to the control unit,
• means responsive to said synchronization pulses to control phase synchronization of the encoding and transmitting means of said network termination unit with said decoding means of the control unit, and
• means responsive to the synchronization pulse from the control unit for transmitting to the control unit an indication of phase nonsynchronization.

A method of communication in a synchronous digital data communication network, comprising the steps of:

• receiving at a controller circuit a stream of binary data pulses in a nonself-clocking format in which clock signals are not carried with the stream of binary data pulses;
• converting the nonself-clocking data stream to a corresponding self-clocking pulse width modulated binary data stream;
• transmitting the pulse width binary modulated data stream to a termination unit of the network;
• extracting a clock signal from the transmitted, binary pulse width modulated data stream received at the termination unit;
• and
• employing the extracted clock signal to decode the transmitted, pulse width modulated data stream to a stream of binary data pulses in nonself-clocking format.

A method of communication in a synchronous digital data communication network, comprising the steps of:

• receiving at a controller circuit a stream of binary data pulses in a nonself-clocking format in which clock signals are not carried with the stream of binary data pulses;
• converting the nonself-clocking data stream to a corresponding self-clocking pulse width modulated binary data stream;
• transmitting the pulse width modulated data stream to a termination unit of the network with preselected transitions at a preselected time during each clock cycle;
• extracting a clock signal from the transmitted, pulse width modulated data stream received at the termination unit;
• and
• employing the extracted clock signal to decode the transmitted, pulse width modulated data stream to a stream of binary data pulses in a nonself-clocking format.