Voice quality optimization on multi-codec calls

• US 6,600,740 B1
• Filed: 10/03/1998
• Issued: 07/29/2003
• Est. Priority Date: 10/03/1998
• Status: Expired due to Term

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Davidson, Walter Lee, Valentine, Eric
• Primary Examiner(s): Vincent, David
• Assistant Examiner(s): NGUYEN, BRIAN D
• Application Number:
  US09/165,663
• Time in Patent Office: 1,760 Days
• Field of Search: 370/252, 370/321, 370/318, 370/337, 370/347, 370/465, 370/464, 370/304, 370/305, 370/324, 370/332, 370/352-357, 370/360, 370/365, 370/514, 370/366, 370/367, 370/369, 370/389, 370/395.5, 370/401, 370/466, 348/14.09, 348/14.02, 348/14.13
• US Class Current: 370/365
• CPC Class Codes: G10L 19/22 Mode decision, i.e. based on audio signal content versus external parameters
• CPC Class Codes: H04L 1/0014 by adapting the source coding
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication

Abstract

A communication network having multiple codecs communicating voice calls between an originating network and a terminating network. The communication network includes an originating codec and a terminating codec. The network provides signaling indicating the decoding algorithm to the originating network, and indicating the encoding algorithm to the terminating network. The original encoding algorithms and the original decoding algorithms are then altered from the standard as a function of this signaling to produce a best fit encoding matching to improve voice quality.

Claims

1. A communications system, comprising:

an originating network, comprising;

a transmitter for transmitting a first signal;

an originating codec coupled to said transmitter for encoding said first signal according to an originating encoding algorithm; and

a signal generator coupled to said transmitter for generating a second signal Identifying said originating encoding algorithm utilized by said originating codec;

and a communications link for connecting said originating network to a terminating network, said terminating network comprising;

a receiver for receiving said first signal;

a terminating codes coupled to said receiver for decoding said first signal;

a storage medium for storing waveforms representative of said originating codec waveforms for assisting in reconstruction of said encoded first signal; and

a processor connected to said receiver for processing said second signal wherein said processor Is capable of analyzing encoding artifacts detected in said first signal and applying said analysis in conjunction with said originating encoding algorithm to reconstruct said first signal.

2. The communications system of claim 1 wherein said signal generator is capable of transmitting said second signal in the same band as said first signal.

3. The communications system of claim 1 wherein said signal generator is capable of transmitting said second signal across a public switched telephone network.

4. The communications system of claim 1 wherein said processor is capable of utilizing said originating encoding algorithm as a pointer to a translation algorithm table connected to said terminating network wherein said table contains coefficients and parameters related to said originating encoding algorithm.

5. The communications system of claim 1 wherein said processor is capable of utilizing said waveforms for altering a decoder algorithm.

6. A communications system for communicating an encoded first signal, comprising:

a terminating network, comprising;

a receiver;

a storage medium for storing waveforms characteristic of an originating codec that encoded said first signal;

a terminating codec coupled to said receiver for decoding said encoded first signal; and

a processor connected to said receiver for receiving said first signal and a second signal for identifying the encoding algorithm of said first signal, wherein said processor is capable of analyzing encoding artifacts detected in said first signal and applying said analysis in conjunction with said encoding algorithm to reconstruct said encoded first signal.

7. The communications system of claim 6, further comprising:

a translation algorithm table for storing coefficients and parameters useful for reconstructing said first signal; and

a detector circuit for detecting said encoding artifacts in said first signal.

8. The communications system of claim 7, wherein said processor is capable of utilizing said originating encoding algorithm as a pointer to said translation algorithm table.

9. The communications system of claim 7 wherein said receiver Is capable of receiving said second signal via the same communications band as said first signal.

10. The communications system of claim 7 wherein said receiver is capable of receiving said second signal via the public switched telephone network.

11. A method of sending a first signal to a terminating network, comprising the steps of:

encoding said first signal utilizing an originating encoding algorithm;

transmitting said encoded first signal from an originating network to said terminating network;

sending a second signal Identifying said originating encoding algorithm to said terminating network;

storing waveforms characteristic of an originating codec that encoded said first signal;

detecting encoding artifacts in said encoded first signal; and

reconstructing, in the terminating network, said encoded first signal utilizing said originating encoding algorithm, said stored waveforms and said encoding artifacts.

12. The method of claim 11 further including the step of transmitting said second signal in the same band as said encoded first signal.

13. The method of claim 11 further comprising the step of transmitting said originating encoding algorithm identifier across a public switched telephone network.

14. The method of claim 11 wherein said step of reconstructing said encoded first signal according to said originating encoding algorithm further comprises analyzing said encoded first signal utilizing said originating encoding algorithm.

15. The method of claim 11 further comprising the steps of:

analyzing said encoding artifacts detected in said encoded first signal; and

applying said analysis of said encoding artifacts and said originating encoding algorithm to reconstruct said encoded first signal.

16. The method of claim 11 further comprising the step of utilizing said originating encoding algorithm as a pointer to a translation algorithm table.

17. A method of receiving an encoded first signal from an originating network, comprising the steps of:

receiving said encoded first signal;

receiving a second signal identifying an encoding algorithm of said encoded first signal;

detecting encoding artifacts in said encoded first signal;

utilizing said identifying second signal for pointing to a translation algorithm table;

accessing stored waveforms characteristic of an originating codec that encoded said first signal;

utilizing said waveforms, said encoding artifacts and said encoding algorithm to reconstruct said encoded first signal; and

decoding said reconstructed encoded first signal utilizing a decoding algorithm corresponding to said encoding algorithm.

18. The method of claim 17 wherein said encoded first signal further includes a start-sync flag, wherein said start-sync flag is utilized by a terminating network to ascertain the start of an encoding period.

19. The method of claim 17 wherein said identifying second signal is transmitted in band with said encoded first signal.

20. The method of claim 17 wherein said identifying second signal is transmitted across a public switched telephone network.