Computer telephony using a circuit-switched network

• US 8,331,357 B2
• Filed: 03/21/2005
• Issued: 12/11/2012
• Est. Priority Date: 03/21/2005
• Status: Expired due to Fees

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Zhang, Yangling
• Primary Examiner(s): Mesfin, Yemane
• Assistant Examiner(s): DUONG, CHRISTINE T
• Application Number:
  US11/084,887
• Publication Number:
  US 20060209811A1
• Time in Patent Office: 2,822 Days
• Field of Search: 370/351, 370/355, 370/357, 370/389, 370/394, 370/458, 370/498, 370/535
• US Class Current: 370/355
• CPC Class Codes: H04M 7/1205 where the types of switching equipement comprises PSTN/ISDN equipment and switching equipment of networks other than PSTN/ISDN, e.g. Internet Protocol networks
• CPC Class Codes: H04Q 2213/13034 A/D conversion, code compression/expansion
• CPC Class Codes: H04Q 2213/13166 Fault prevention
• CPC Class Codes: H04Q 2213/13199 Modem, modulation
• CPC Class Codes: H04Q 2213/13298 Local loop systems, access network
• CPC Class Codes: H04Q 2213/1332 Logic circuits

Abstract

Apparatus for placing a plurality of computer-assisted compressed-voice subscriber calls using a circuit-switched signal path in a distributed telecommunications network. A plurality of vocoders receive voice data from respective subscriber voice devices and output substantially continuous compressed-voice data signals which are arranged by a plurality of packetizers into compressed-voice data packets. A plurality of network adapters send the compressed-voice data packets to a circuit-switched telephone network. A plurality of sequencers remove the substantially continuous compressed-voice data signals from the compressed-voice data packets. A multiplexer coupled to the sequencers combines the compressed-voice data signals into a compressed-voice data package and a signal injector injects the compressed-voice data package into a prearranged time slot of a conventional circuit-switched signal path. Upon arrival at the destination, the time slot carrying the compressed-voice data is disassembled and compressed-voice data is routed to destination subscriber premises. Circuit-switched telephone networks can now be employed to carry compressed voice, allowing simultaneous voice and data communications, while still providing low cost and high quality voice service.

Claims

1. An apparatus, comprising:

a line unit and a compressed-voice module, wherein the compressed-voice module comprises a sequencer and a packet separator coupled to said sequencer;

wherein said packet separator receives data packet traffic from an originating subscriber premises, wherein the data packet traffic comprises compressed-voice data packets and second data packets;

wherein said compressed-voice data packets have a first identifying header;

said second data packets have a second identifying header; and

said packet separator diverts said second data packets from said compressed-voice data packets upon detection of the second identifying header;

wherein said sequencer extracts first compressed-voice data signals from the compressed-voice data packets;

the apparatus further comprising a multiplexer that combines a plurality of substantially continuous compressed-voice data signals from a plurality of respective originating subscriber premises into a compressed-voice data package, wherein the plurality of respective originating subscriber premises comprise the originating subscriber premises, wherein the plurality of substantially continuous compressed-voice data signals comprise the first compressed-voice data signals from the sequencer; and

a signal injector injecting said compressed-voice data package into a prearranged time slot, of a circuit-switched, time division multiplexed (TDM) signal path of a public switched telephone network (PSTN), that is dedicated for the compressed-voice data package;

the apparatus further comprising a switching module of a local switching office of the PSTN, wherein the switching module comprises the line unit, the compressed-voice module, the sequencer, the multiplexer, and the signal injector.

2. The apparatus of claim 1 wherein said circuit-switched, time division multiplexed signal path comprises a time division multiplexed signal path carrying a sequence of time slots;

wherein at least one time slot of the sequence of time slots is dedicated for compressed-voice data packages.

3. The apparatus of claim 1 further comprising:

a plurality of sequencers coupled to said multiplexer, wherein the plurality of sequencers comprise the sequencer;

wherein the switching module comprises the plurality of sequencers;

wherein the plurality of sequencers receive a plurality of compressed-voice data packets that comprise the plurality of substantially continuous compressed-voice data signals;

wherein the plurality of sequencers recover said plurality of substantially continuous compressed-voice data signals from the plurality of compressed-voice data packets.

14. The apparatus of claim 1, wherein a bit rate of the first compressed-voice data signals is selected to be a fraction of a bit rate of the circuit-switched TDM signal path.

15. The apparatus of claim 2, wherein the at least one time slot of the sequence of time slots is dedicated for compressed-voice data packages of computer-assisted calls.

4. An apparatus, comprising:

a switching module of a local switching office of a public switched telephone network, wherein the switching module comprises a multiplexer, a signal injector, a plurality of sequencers, a plurality of line units, and a plurality of compressed-voice modules;

the multiplexer combining a plurality of substantially continuous compressed-voice data signals from a plurality of originating subscriber premises into a compressed-voice data package;

the signal injector injecting said compressed-voice data package into a prearranged time slot, of a circuit-switched, time division multiplexed (TDM) signal path of a public switched telephone network (PSTN), that is dedicated for the compressed-voice data package;

the plurality of sequencers coupled to said multiplexer, having a plurality of compressed-voice data packets containing said substantially continuous compressed-voice data signals and recovering therefrom said substantially continuous compressed-voice data signals;

the plurality of line units coupled to the plurality of sequencers and a plurality of compressed-voice modules containing said plurality of sequencers, coupled to said plurality of line units,

wherein said compressed-voice modules further comprise packet separators coupled to said sequencers,

wherein said packet separators receive data packet traffic from the plurality of originating subscriber premises which comprises the compressed-voice data packets and second data packets, wherein said packet separators divert said second data packets from said plurality of sequencers; and

wherein said compressed-voice data packets have a first identifying header;

said second data packets have a second identifying header; and

said packet separators divert said second data packets from said compressed-voice data packets upon detection of the second identifying header.

5. The apparatus of claim 4 wherein:

said plurality of line units are coupled to a second signal path distinct from said circuit-switched TDM signal path;

said packet separators are coupled to said line units; and

said second data packets separated from said plurality of sequencers are sent to said line units by said packet separators for sending along said second signal path.

6. The apparatus of claim 4, the switching module further comprising:

a signal extractor extracting a compressed-voice data package from the prearranged time slot of the circuit-switched TDM signal path;

a plurality of receiving sequencers of a circuit-switched telephone network;

a demultiplexer coupled to said plurality of receiving sequencers, separating said compressed-voice data package into a plurality of compressed-voice data signals; and

the plurality of receiving sequencers receiving the compressed-voice data signals and arranging the compressed-voice data signals into compressed-voice data packets.

7. The apparatus of claim 6 further comprising a plurality of sending modems coupled to respective ones of said receiving sequencers to transmit compressed-voice data packets to respective subscribers.

8. The apparatus of claim 4 wherein said substantially continuous compressed-voice data signals have a data rate not substantially lower than 8 kbps.

9. The apparatus of claim 4 wherein no more than eight of said compressed-voice data signals are combined into said compressed-voice data package.

10. A method, comprising the steps of:

receiving, at a switching module of a local switching office of a circuit-switched telephone network, a plurality of compressed-voice data packets having a first identifying header along with a plurality of non-telephone call data packets having a second identifying header;

separating, by a packet separator of the switching module, the plurality of compressed-voice data packets from the plurality of non-telephone call data packets based on at least one of the first and second identifying headers;

recovering, by a sequencer of the switching module, a plurality of substantially continuous compressed-voice data signals from the plurality of compressed-voice data packets;

combining, by a multiplexer of the switching module, said plurality of substantially continuous compressed-voice data signals to form a compressed-voice data package; and

injecting, by a signal injector of the switching module, said compressed-voice data package into a prearranged time slot, of a circuit-switched, time division multiplexed (TDM) signal path of a public switched telephone network (PSTN), that is dedicated for the compressed-voice data package.

11. The method of claim 10 wherein said circuit-switched TDM signal path comprises a time division multiplexed signal path carrying a sequence of time slots.

12. The method of claim 10 wherein said substantially continuous compressed-voice data signals have a data rate not substantially lower than 8 kbps.

13. The method of claim 10 wherein no more than eight of said compressed-voice data signals are combined into said compressed-voice data package.