Voice playout buffer for dual-PHY based integrated access device

• US 7,289,532 B2
• Filed: 05/19/2003
• Issued: 10/30/2007
• Est. Priority Date: 06/21/2002
• Status: Active Grant

• Current Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Original Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Inventors: McMahan, Dennis B., Herron, Phillip Stone, Gieger, Darrin L.
• Primary Examiner(s): Kizou; Hassan
• Assistant Examiner(s): Moutaouakil; Mounir
• Application Number:
  US10/441,091
• Publication Number:
  US 20030235221A1
• Time in Patent Office: 1,625 Days
• Field of Search: 370/498, 370/508, 370/419, 370/463, 370/545, 370/321, 370/326, 370/336, 370/347, 370/442, 370/458, 370/337, 370/250, 370/465, 370/466, 709/250
• US Class Current: 370/466
• CPC Class Codes: H04L 2012/5671 Support of voice
• CPC Class Codes: H04L 49/20 Support for services
• CPC Class Codes: H04L 49/30 Peripheral units, e.g. input or output ports
• CPC Class Codes: H04L 49/3081 ATM peripheral units, e.g. policing, insertion or extraction

Abstract

A voice playout buffer for a dual PHY-based integrated access device platform has a plurality of voice signal buffer sections. A respective buffer section has a capacity in excess of the number of digitized voice signal bytes contained in a respective cell-based communication signal. The storage capacity of a buffer section accommodates a communications control processor writing new outgoing digitized voice signal bytes into the first portion of the voice signal buffer section for transport over a TDM communication link, prior to digitized voice signals newly received from the TDM communication link being written into the first portion of the voice signal buffer section.

Claims

1. An apparatus for interfacing multiple channels of digitized voice signals with a cell-based communication link comprising:

a first port configured to be coupled with a time division multiplexed (TDM) communication link over which respective ones of said multiple channels of digitized voice signals are transported at a first data rate;

a second port configured to be coupled with a cell-based communication link over which cell-based communication signals are transported at a second data rate higher than said first data rate; and

a multi-channel voice signal buffer containing multiple voice signal buffer sections respectively associated with said multiple channels of digitized voice signals, a respective voice signal buffer section having a storage capacity, in excess of the number of voice signal components contained in a respective cell-based communication signal by an amount that is sufficient to allow said respective cell-based communication signal to be read out from a first portion of said respective voice signal buffer section via said second port and transported over said cell-based communication link, and to allow an incoming cell-based communication signal from said cell-based communication link to be written into said first portion of said respective voice signal buffer section for delivery of digitized voice signals contained in said incoming cell-based communication signal to said first port, prior to newly received digitized voice signals received at said first port from said time division multiplexed (TDM) communication link being written into said first portion of said respective voice signal buffer section.

2. The apparatus according to claim 1, wherein said cell-based communication link comprises a full-duplex cell-based communication link that is coupled with a communications control processor, said communications control processor being operative, in response to receipt from said cell-based communication link of an incoming cell-based communication signal containing said multiple channels of digitized voice signals received from said first port, to return an outgoing cell-based communication signal containing said multiple channels of digitized voice signals for storage in first portions of voice signal buffer sections for said multiple channels of digitized voice signals, prior to digitized voice signals newly received at said first port from said TDM communication link being written into said first portions of voice signal buffer sections for said multiple channels of digitized voice signals.

3. The apparatus according to claim 1, wherein said respective voice signal buffer section has a storage capacity that exceeds the number of digitized voice bytes contained in a respective cell-based communication signal by a prescribed number of bytes per channel.

4. The apparatus according to claim 3, wherein said prescribed number of bytes per channel at said first data rate is sufficient to prevent digitized voice signals newly received at said first port from said TDM communication link from written into said first portions of voice signal buffer sections for said multiple channels of digitized voice signals, prior to reading out therefrom of new outgoing digitized voice signal bytes for transport over said TDM communication link.

5. The apparatus according to claim 1, wherein said cell-based communication link comprises a Universal Test and Operations Physical (PHY) Interface for asynchronous transfer mode (ATM) (UTOPIA) communication link.

6. A method of interfacing multiple channels of digitized voice signals with a cell-based communication link comprising the steps of:

(a) providing a multi-channel voice signal buffer containing multiple voice signal buffer sections, respectively associated with multiple channels of digitized voice signals, that are transported over a time division multiplexed (TDM) communication link at a first data rate, a respective voice signal buffer section having a prescribed storage capacity in excess of the number of voice signal components contained in a respective cell-based communication signal transported over said cell-based communication link;

(b) sequentially writing digitized voice signals of a respective TDM channel into successive storage locations of a first portion of a respective voice signal buffer section of said multi-channel voice signal buffer at a first data rate;

(c) reading out said digitized voice signals written in step (b), from said first portion of each voice signal buffer section of said multi-channel voice signal buffer, containing digitized voice signals received from said TDM communication link, for transport over said cell-based communication link at a second data rate greater than said first data rate;

(d) writing digitized voice signal components contained in incoming cell-based communication signals from said cell-based communication link into said first portion of said respective voice signal buffer section and reading out from said first portion of said respective voice signal buffer section digitized voice signals written therein for transport over said TDM communication link at said first data rate, prior to digitized voice signals newly received from said TDM communication link being written into said first portion of said respective voice signal buffer section.

7. The method according to claim 6, wherein said respective voice signal buffer section has a storage capacity that exceeds the number of digitized voice bytes contained in a respective cell-based communication signal by a prescribed number of bytes per channel.

8. The method according to claim 7, wherein said prescribed number of bytes per channel at said first data rate is sufficient to prevent digitized voice signals newly received at a first port from said TDM communication link from written into said first portions of voice signal buffer sections for said multiple channels of digitized voice signals, prior to reading out therefrom of new outgoing digitized voice signal bytes for transport over said TDM communication link.

9. The method according to claim 6, wherein said cell-based communication link comprises a full-duplex cell-based communication link that is coupled with a communications control processor, said communications control processor being operative, in response to receipt from said cell-based communication link of an incoming cell-based communication signal containing said multiple channels of digitized voice signals received from said first port, to return an outgoing cell-based communication signal containing said multiple channels of digitized voice signals for storage in first portions of voice signal buffer sections for said multiple channels of digitized voice signals, prior to digitized voice signals newly received at said first port from said TDM communication link being written into said first portions of voice signal buffer sections for said multiple channels of digitized voice signals.

10. The method according to claim 6, wherein said cell-based communication link comprises a Universal Test and Operations Physical (PHY) Interface for asynchronous transfer mode (ATM) (UTOPIA) communication link.

11. A voice playout buffer for interfacing multiple channels of digitized voice signals from respective time division multiplex (TDM) communication channels of a TDM communication link with a communications control processor by way cell-based communication link comprising:

a first port coupled with said TDM communication link over which respective ones of said multiple channels of digitized voice signals are transported at a first data rate;

a second port configured to be coupled with said cell-based communication link over which cell-based communication signals are transported to and received from said communications control processor at a second data rate higher than said first data rate; and

a multi-channel voice signal buffer having a plurality of voice signal buffer sections respectively associated with said multiple channels of digitized voice signals,

a respective voice signal buffer section having a storage capacity in excess of the number of digitized voice signal bytes contained in a respective cell-based communication signal, and being operative to sequentially store digitized voice signals of a respective TDM channel into successive storage locations of a first portion thereof at said first data rate, and to read out said digitized voice signals written into said first portion of said respective voice signal at said second data rate; and

wherein

said storage capacity of said respective voice signal buffer section is such as to accommodate said communications control processor writing new outgoing digitized voice signal bytes into said first portion of said respective voice signal buffer section for transport over said TDM communication link, prior to digitized voice signals newly received from said TDM communication link being written into said first portion of said respective voice signal buffer section.

12. The voice playout buffer according to claim 11, wherein said respective voice signal buffer section has a storage capacity that exceeds the number of digitized voice bytes contained in a respective cell-based communication signal by a prescribed number of bytes per channel.

13. The voice playout buffer according to claim 12, wherein said prescribed number of bytes per channel at said first data rate is sufficient to prevent digitized voice signals newly received at said first port from said TDM communication link from being written into said first portions of voice signal buffer sections for said multiple channels of digitized voice signals prior to reading out therefrom of new outgoing digitized voice signal bytes from said communications control processor for transport over said TDM communication link.

14. The voice playout buffer according to claim 11, wherein said cell-based communication link comprises a Universal Test and Operations Physical (PHY) Interface for asynchronous transfer mode (ATM) (UTOPIA) communication link.