Method and apparatus for providing on-hook transmission for digital loop carrier channel units

Claim 1

A method of providing a voice frequency (VF) path for on-hook VF transmission through each of a plurality of channel units, each including a subscriber line interface circuit chip (SLIC), to a subscriber telephone instrument in a digital loop carrier (DLC) system for providing POTS-type telephone service using DC signalling to the subscriber telephone instrument comprising the steps of providing a control unit operatively associated with each channel unit for passing signals including VF and DC signals in both directions for transmit and receive communication channels, and generating with the control unit control signals for each channel unit for causing a portion of the channel unit to establish a communication path through each such portion in response to receipt by the control unit of an "idle" code in ground start mode during idle condition regardless of whether the subscriber instrument is on-hook or off-hook, thereby facilitating on-hook transmission.

Claim 2

A method of providing a voice frequency (VF) path for on-hook VF transmission through each of a plurality of channel units, each including a subscriber line interface circuit chip (SLIC), to a subscriber telephone instrument in a digital loop carrier (DLC) system for providing POTS-type telephone service using DC signalling to the subscriber telephone instrument comprising the steps of providing a control unit operatively associated with each channel unit for passing signals including VF and DC signals in both directions for transmit and receive communication channels, and generating with the control unit control signals for each channel unit for causing a portion of the channel unit to establish a communication path through each such portion in response to receipt by the control unit of an "idle" code in ground start mode during idle condition regardless of whether the subscriber instrument is on-hook or off-hook, thereby facilitating on-hook transmission.

Claim 3

An apparatus for providing a voice frequency (VF) path for on-hook VF transmission through each of a plurality of channel units, each including a subscriber line interface circuit chip (SLIC), to a subscriber telephone instrument in a digital loop carrier system for providing POTS-type telephone service using DC signalling to the subscriber telephone instrument comprising the combination of control unit means operatively associated with each channel unit for passing signals including VF and DC signals in both directions for transmit and receive communication channels, and means in each said control unit for generating control signals for said associated channel unit for establishing through a portion of the channel unit a communication path in response to receipt by said control unit means of an "idle" code in ground start mode during idle condition regardless of whether said subscriber instrument is on-hook or off-hook, thereby permitting on-hook transmission.

Claim 4

An apparatus for providing a voice frequency (VF) path for on-hook VF transmission through each of a plurality of channel units, each including a subscriber line interface circuit chip (SLIC), to a subscriber telephone instrument in a digital loop carrier system for providing POTS-type telephone service using DC signalling to the subscriber telephone instrument comprising the combination of control unit means operatively associated with each channel unit for passing signals including VF and DC signals in both directions for transmit and receive communication channels, and means in each said control unit for generating control signals for said associated channel unit for establishing through a portion of the channel unit a communication path in response to receipt by said control unit means of an "idle" code in ground start mode during idle condition regardless of whether said subscriber instrument is on-hook or off-hook, thereby permitting on-hook transmission.

Claim 6

A method of providing a voice frequency (VF) path for on-hook signaling through each of a plurality of channel units, each including a subscriber line interface circuit chip (SLIC), to a subscriber telephone instrument in a digital loop carrier (DLC) system for providing POTS type telephone service using DC signaling to the subscriber telephone instrument comprising providing a control unit operatively associated with each channel unit for passing signals including VF and DC signals in both directions for transmit and receive communication channels, and generating, with the control unit, control signals for the associated channel unit for establishing a communication path through the associated channel unit in response to receipt by the control unit of an "idle" code in ground start mode during idle condition regardless of whether the subscriber instrument is on-hook or off-hook, thereby facilitating on-hook transmission.

Claim 7

A method of providing a voice frequency (VF) path for on-hook signaling through each of a plurality of channel units, each including a subscriber line interface circuit chip (SLIC), to a subscriber telephone instrument in a digital loop carrier (DLC) system for providing POTS type telephone service using DC signaling to the subscriber telephone instrument comprising providing a control unit operatively associated with each channel unit for passing signals including VF and DC signals in both directions for transmit and receive communication channels, and generating, with the control unit, control signals for the associated channel unit for establishing a communication path through the associated channel unit in response to receipt by the control unit of an "idle" code in ground start mode during idle condition regardless of whether the subscriber instrument is on-hook or off-hook, thereby facilitating on-hook transmission.

Claim 8

An apparatus for providing a voice frequency (VF) path for on-hook signaling through each of a plurality of channel units, each including a subscriber line interface circuit chip (SLIC), to a subscriber telephone instrument in a digital loop carrier (DLC) system for providing POTS-type telephone service using DC signaling to the subscriber telephone instrument comprising the combination of control unit means operatively associated with each channel unit for passing signals including DC and VF signals in both directions for transmit and receive communication channels, and means in each said control unit for generating control signals for the channel unit for establishing through each portion of the channel unit a communication path in response to receipt by said control unit means of an "idle" code in ground start mode during idle condition regardless of whether the subscriber instrument is on-hook or off-hook, thereby permitting on-hook transmission.

Claim 9

An apparatus for providing a voice frequency (VF) path for on-hook signaling through each of a plurality of channel units, each including a subscriber line interface circuit chip (SLIC), to a subscriber telephone instrument in a digital loop carrier (DLC) system for providing POTS-type telephone service using DC signaling to the subscriber telephone instrument comprising the combination of control unit means operatively associated with each channel unit for passing signals including DC and VF signals in both directions for transmit and receive communication channels, and means in each said control unit for generating control signals for the channel unit for establishing through each portion of the channel unit a communication path in response to receipt by said control unit means of an "idle" code in ground start mode during idle condition regardless of whether the subscriber instrument is on-hook or off-hook, thereby permitting on-hook transmission.