Internet telephone service using cellular digital vocoder

• US 6,570,871 B1
• Filed: 10/08/1996
• Issued: 05/27/2003
• Est. Priority Date: 10/08/1996
• Status: Expired due to Term

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Services Corporation (Verizon Communications Inc.)
• Inventors: Schneider, Allan
• Primary Examiner(s): Nguyen, Steven
• Assistant Examiner(s): Nguyen, Phuongchau Ba
• Application Number:
  US08/727,730
• Time in Patent Office: 2,422 Days
• Field of Search: 375/200, 370/328, 370/335, 370/338, 370/337, 370/401, 370/389, 370/342, 370/352, 370/356, 455/433, 455/445, 455/560
• US Class Current: 370/356
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/75 Media network packet handling
• CPC Class Codes: H04L 65/756 adapting media to device capabilities
• CPC Class Codes: H04M 2207/18 wireless networks
• 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: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 4/18 Information format or content conversion, e.g. adaptation by the network of the transmitted or received information for the purpose of wireless delivery to users or terminals
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

A system and method for providing telephone type services over the internetwork commonly known as the Internet. Wireless digital telephones in communication with wireless digital communications systems have speech coders that generate digital voice samples, and encoders that encode the digital voice samples to minimize bit errors during RF transmission. The wireless digital communications system demodulates the received modulated wireless signal transmitted by the digital telephone to recover the encoded, digital voice samples. The error correction codes within the encoded, digital voice samples are removed to recover the original digital voice samples generated by the vocoder in the digital telephone. The decoded digital voice samples are then supplied to a gateway interface that packetizes the decoded digital voice samples into digital voice sample segments, assigns a packet address corresponding to the destination telephone number, and outputs the digital voice sample segments as data packets onto a packet switched network, such as the Internet, for reception by a network node corresponding to the destination address.

Claims

1. In a wireless digital communications system receiving a modulated wireless signal from a digital telephone, the digital telephone having a subscriber telephone number and a vocoder for compression of voice signals to generate digital vocoder voice samples in a vocoder protocol specifically adapted for the wireless digital communications system, the modulated wireless signal carrying an encoded form of the digital vocoder voice samples as encoded, digital voice samples for a destination telephone number, a system comprising:

a first wireless transceiver having a demodulator demodulating the received modulated wireless signal and outputting a first data stream carrying the encoded, digital voice samples;

a decoder decoding the encoded, digital voice samples and in response outputting said digital vocoder voice samples from the first data stream in said vocoder protocol; and

a gateway interface sending and receiving packet data via a packet switched network, the gateway interface having a packet assembler/disassembler receiving said digital vocoder voice samples in the vocoder protocol, the packet assembler/disassembler packetizing the received digital vocoder voice samples into data packets having a destination address corresponding to said destination telephone number, the gateway interface outputting said data packets onto the packet switched network for reception by a network node corresponding to said destination address.

2. The system of claim 1, wherein the packet switched network is Internet, the gateway interface supplying the data packets with an IP address as said destination address and outputting the data packets onto Internet.

3. The system of claim 1, wherein the gateway interface further comprises a router outputting said destination address in response to reception of the destination telephone number.

4. The system of claim 1, further comprising a second gateway interface corresponding to said network node, the second gateway interface recovering and outputting the digital vocoder voice samples from the data packets.

5. The system of claim 4, further comprising a transcoder outputting the recovered digital vocoder voice samples onto tandem trunk telephone lines.

6. The system of claim 5, further comprising a speech coder receiving the recovered digital vocoder voice samples from the tandem trunk lines and outputting analog voice signals onto an analog telephone line.

7. The system of claim 4, further comprising:

a switching controller outputting the recovered digital vocoder voice samples; and

a second wireless transceiver transmitting the recovered digital vocoder voice samples from the switching controller as a second modulated wireless signal to a second digital telephone assigned the destination telephone number.

8. The system of claim 7, wherein the second wireless transceiver comprises a modulator modulating the recovered digital vocoder voice samples into one of a time division multiplexed digital signal and a code division multiplexed digital signal.

9. The system of claim 7, further comprising a speech coder outputting analog voice signals to the second wireless transceiver in response to reception of the recovered digital vocoder voice samples from the second switching controller.

10. The system of claim 1, wherein the encoded, digital voice samples are received from the digital telephone in an interleaved sequence, the decoder comprising:

a deinterleaver reordering a frame sequence of the encoded, digital voice samples; and

a convolutional decoder decoding the encoded, digital voice samples.

11. The system of claim 10, wherein the decoder further comprises a cyclic redundancy check (CRC) decoder detecting presence of errors in the encoded, digital voice samples.

12. The system of claim 1, wherein the gateway interface has a predetermined network address, the gateway interface receiving second data packets carrying second digital vocoder voice samples and having a destination address corresponding to said predetermined network address from the packet switched network.

13. The system of claim 12, wherein the gateway interface sends and receives the first and second data packets to and from the packet switched network in Internet Protocol.

14. The system of claim 13, wherein the gateway interface sends and receives the first and second data packets according to TCP/IP protocol.

15. The system of claim 14, further comprising a switching controller selectively routing the second digital voice samples, received from the gateway interface, to one of the first wireless transceiver and a public switched telephone network.

16. The system of claim 15, wherein the received second data packets have a payload carrying the second digital vocoder voice samples and a second destination telephone number, the switching controller routing the digital vocoder voice samples in response to the second destination telephone number.

17. The system of claim 15, wherein the received second data packets have a payload carrying second digital vocoder voice samples and a session identifier, the switching controller routing the digital vocoder voice samples in response to the session identifier.

18. The system of claim 15, wherein the destination address identifies a second destination telephone number, the switching controller routing the digital vocoder voice samples in response to the destination address.

19. The system of claim 1, wherein the first transceiver is a time division multiple access transceiver.

20. The system of claim 1, wherein the first transceiver is a code division multiple access transceiver.

21. A wireless digital communications system providing wireless voice communications with a digital telephone transmitting a first modulated wireless signal carrying first vocoder voice samples of compressed digitized voice signals in a vocoder protocol specifically adapted for the wireless digital communications system, the wireless digital communications system comprising:

at least one wireless transceiver receiving the first modulated wireless signal and in response outputting a data stream carrying said first vocoder voice samples in the vocoder protocol;

an interface coupled to the wireless transceiver for receiving said first vocoder voice samples in the vocoder protocol, the interface packetizing the received first vocoder voice samples from the data stream into first data packets, the interface also assembling second vocoder voice samples compressed and digitized in the vocoder protocol from second data packets and encoding the assembled second vocoder voice samples for transmission to the digital telephone via the transceiver; and

a router outputting the first data packets onto a packet switched network for reception by a destination telephone station and for receiving from the packet switched network said second data packets carrying said second vocoder voice samples representing voice signals from said destination telephone station in compressed digitized form in the vocoder protocol.

22. The system of claim 21, wherein encoded, first vocoder voice samples are received from the digital telephone in an interleaved sequence, the interface comprising:

a deinterleaver reordering a frame sequence of the encoded, first vocoder voice samples; and

a convolutional decoder decoding the encoded, first vocoder voice samples.

23. The system of claim 22, wherein the interface further comprises a packet assembler/disassembler assembling and disassembling the second vocoder voice samples and the decoded vocoder voice samples, respectively.

24. A method, comprising:

digitizing and compressing speech signals to form vocoder speech samples in a specific vocoder protocol adapted for wireless speech communication by a wireless communications network;

transporting the vocoder speech samples to a gateway interface, the vocoder speech samples remaining in said vocoder protocol throughout transport to the gateway interface;

packetizing the vocoder speech samples in said vocoder protocol within packets of an internetwork protocol;

including in each of the packets an internetwork address corresponding to a destination telephone number; and

transmitting the addressed packets containing the vocoder speech samples in said vocoder protocol through a public, packet-switched internetwork.

25. A method as in claim 24, wherein the step of transporting comprises:

encoding and modulating the vocoder speech samples;

sending the encoded and modulated vocoder speech samples over an air-link;

receiving signals from the air link;

demodulating and decoding the received signals to recover the vocoder speech samples in said vocoder protocol; and

transporting the recovered vocoder speech samples to the gateway interface.

26. A method as in claim 24, wherein the public, packet-switched internetwork comprises the Internet.

27. A method as in claim 24, further comprising:

receiving the addressed packets containing the vocoder speech samples in said vocoder protocol through the public, packet-switched internetwork;

recovering the vocoder speech samples in said vocoder protocol; and

communicating speech information of the samples through a telephone network to a destination station associated with the destination telephone number.

28. A method as in claim 27, wherein the step of communicating speech information comprises:

transporting the vocoder speech samples in said vocoder protocol recovered from the packets to another wireless communication network; and

sending the vocoder speech samples in said vocoder protocol recovered from the packets through said another wireless communication network to a wireless station associated with the destination telephone number.

29. A method as in claim 27, wherein the step of communicating speech information comprises:

converting the vocoder speech samples recovered from the packets from said vocoder protocol to speech signals in a protocol compatible with transport through a public switched telephone network; and

sending the speech signals through the public switched telephone network.

30. A method as in claim 24, wherein the vocoder speech samples in a protocol comprise digital samples digitized and compressed with a coding algorithm conforming to requirements of the wireless communications network.

31. A method as in claim 30, wherein the coding algorithm comprises an algorithm selected from the group consisting of:

Regular Pulse Excitation (RPE) coding, Linear Predictive Coding (LPC), excited linear predictive (CELP) coding and vector-sum excited linear predictive (VSELP) coding.