TANDEM-FREE VOCODER OPERATIONS BETWEEN NON-COMPATIBLE COMMUNICATION SYSTEMS

• US 20090281799A1
• Filed: 07/16/2009
• Published: 11/12/2009
• Est. Priority Date: 10/28/2002
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: El-Maleh, Khaled Helmi, Kandhadai, Ananthapadmanabhan Arasanipalai
• Granted Patent: US 7,969,902 B2
• Time in Patent Office: Days
• US Class Current: 704/221
• CPC Class Codes: G10L 19/173 Transcoding, i.e. converting between two coded representations avoiding cascaded coding-decoding
• CPC Class Codes: H04W 88/181 Transcoding devices; Rate adaptation devices

Abstract

Tandem-free vocoder operations (TFO) between non-compatible communication systems may be enabled through hardware modifications at communication elements within each system. In one aspect, each infrastructure entity in System 1 comprises an intra-system TFO Frame Generator G₁, an intra-system TFO Frame Extractor E₁, and a TFO Frame Extractor E₂ of System 2, which is non-compatible to System 1. Each infrastructure entity in System 2 comprises an intra-system TFO Frame Generator G₂, an intra-system TFO Frame Extractor E₂, and a TFO Frame Extractor E₁ of System 1.

Claims

1. A method of determining tandem-free operation (TFO) contents in a TFO frame comprising:

receiving a TFO frame comprising a punctured PCM stream, wherein TFO contents is punctured into the PCM stream;

extracting a source type parameter from a predetermined location in the TFO frame to determine a TFO source type;

extracting intra-system parameters from the TFO frame to determine the TFO contents if the TFO source type is intra-system; and

extracting intersystem parameters from the TFO frame to determine the TFO contents if the TFO source type is intersystem.

2. The method of claim 1 wherein extracting intra-system parameters comprises:

locating an intra-system parameter in the TFO frame based on the TFO source type and a first predetermined table; and

extracting the intra-system parameter.

3. The method of claim 1 wherein extracting intersystem parameters comprises:

locating an intersystem parameter in the TFO frame based on the TFO source type and a second predetermined table; and

extracting the intersystem parameter.

4. The method of claim 1 wherein the punctured PCM stream comprises a plurality of PCM

symbols wherein the plurality of PCM symbols are altered by replacing a predetermined number of least significant bits with received vocoder frame bits.

5. The method of claim 1 wherein the source type identifies a vocoder selected from the group consisting of GSM vocoder, UMTS vocoder, CDMA vocoder, and W-CDMA vocoder.

6. An apparatus for determining tandem-free operation (TFO) contents in a TFO frame comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being capable of executing the steps of;

receiving a TFO frame comprising a punctured PCM stream, wherein TFO contents is punctured into the PCM stream;

extracting a source type parameter from a predetermined location in the TFO frame to determine a TFO source type;

extracting intra-system parameters from the TFO frame to determine the TFO contents if the TFO source type is intra-system; and

extracting intersystem parameters from the TFO frame to determine the TFO contents if the TFO source type is intersystem.

7. The apparatus of claim 6 wherein the memory further comprises instructions, the instructions being capable of executing the steps of:

locating an intra-system parameter in the TFO frame based on the TFO source type and a

first predetermined table; and

extracting the intra-system parameter.

8. The apparatus of claim 6 wherein the memory further comprises instructions, the instructions being capable of executing the steps of:

locating an intersystem parameter in the TFO frame based on the TFO source type and a

first predetermined table; and

extracting the intersystem parameter.

9. The apparatus of claim 6 wherein the punctured PCM stream comprises a plurality of PCM symbols wherein the plurality of PCM symbols are altered by replacing a predetermined number of least significant bits with received vocoder frame bits.

10. The apparatus of claim 6 wherein the source type identifies a vocoder selected from the group consisting of GSM vocoder, UMTS vocoder, CDMA vocoder, and W-CDMA vocoder.

11. An apparatus for determining tandem-free operation (TFO) contents in a TFO frame comprising:

means for receiving a TFO frame comprising a punctured PCM stream, wherein TFO contents is punctured into the PCM stream;

means for extracting a source type parameter from a predetermined location in the TFO frame to determine a TFO source type;

means for extracting intra-system parameters from the TFO frame to determine the TFO contents if the TFO source type is intra-system; and

means for extracting intersystem parameters from the TFO frame to determine the TFO contents if the TFO source type is intersystem.

12. The apparatus of claim 11 wherein means for extracting intra-system parameters comprises:

means for locating an intra-system parameter in the TFO frame based on the TFO source type and a first predetermined table; and

means for extracting the intra-system parameter.

13. The apparatus of claim 11 wherein means for extracting intersystem parameters comprises:

means for locating an intersystem parameter in the TFO frame based on the TFO source type and a second predetermined table; and

means for extracting the intersystem parameter.

14. The apparatus of claim 11 wherein the punctured PCM stream comprises a plurality of PCM

symbols wherein the plurality of PCM symbols are altered by replacing a predetermined number of least significant bits with received vocoder frame bits.

15. The apparatus of claim 11 wherein the source type identifies a vocoder selected from the group consisting of GSM vocoder, UMTS vocoder, CDMA vocoder, and W-CDMA vocoder.

16. A memory storing a computer program that, when executed, causes a computer to perform the acts of:

receiving a TFO frame comprising a punctured PCM stream, wherein TFO contents is punctured into the PCM stream;

extracting a source type parameter from a predetermined location in the TFO frame to determine a TFO source type;

extracting intra-system parameters from the TFO frame to determine the TFO contents if the TFO source type is intra-system; and

extracting intersystem parameters from the TFO frame to determine the TFO contents if the TFO source type is intersystem.