Temporal alignment of codec data with wireless local area network RF slots

• US 7,277,420 B2
• Filed: 11/13/2002
• Issued: 10/02/2007
• Est. Priority Date: 02/12/2002
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Aragones, Charles, Lee, Sherman, Chou, Vivian
• Primary Examiner(s): Perez-Gutierrez; Rafael
• Assistant Examiner(s): AJIBADE AKONAI, OLUMIDE
• Application Number:
  US10/293,452
• Publication Number:
  US 20030152057A1
• Time in Patent Office: 1,784 Days
• Field of Search: 370/338, 370/351, 370/503, 370/350, 455/41.2, 455/550.2, 455/552.1, 455/553.1, 375/242, 375/219, 375/220, 704/212, 341/50, 341/126
• US Class Current: 370/350
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A wireless local area network (WLAN) transceiving integrated circuit services voice communications in a WLAN with at least one other WLAN device. The WLAN transceiving integrated circuit includes a WLAN interface, an input buffer, a transcoder, and a processor. The WLAN interface wirelessly communicates with the at least one WLAN device to receive packetized audio data from the at least one WLAN device. The input buffer operably couples to the WLAN interface and receives the packetized audio data from the WLAN interface. The transcoder operably couples to the input buffer and receives the packetized audio data from the input buffer. The transcoder converts the packetized audio data to Pulse Code Modulated (PCM) audio data and outputs the PCM audio data to a coupled audio COder/DECoder (CODEC). The processor operably couples to the WLAN interface, the input buffer, and the transcoder. The transcoder outputs the PCM audio data to the audio CODEC such that the PCM audio data is substantially temporally aligned with Radio Frequency (RF) slots of the WLAN interface.

Claims

1. A Wireless Local Area Network (WLAN) transceiving integrated circuit that services voice communications in a WLAN with at least one WLAN device, the WLAN transceiving integrated circuit comprising:

a WLAN interface that wirelessly communicates with the at least one WLAN device to receive packetized audio data from the at least one WLAN device;

an input buffer operably coupled to the WLAN interface that receives the packetized audio data from the WLAN interface;

a transcoder operably coupled to the input buffer that receives the packetized audio data from the input buffer, that converts the packerized audio data to Pulse Code Modulated (PCM) audio data, and that outputs the PCM audio data to a coupled audio COder/DECoder (CODEC);

a processor operably coupled to the WLAN interface, the input buffer, and the transcoder; and

wherein the transcoder outputs the PCM audio data to the audio CODEC such that the PCM audio data is substantially temporally aligned with Radio Frequency (RF) slots of the WLAN interface.

2. The WLAN transceiving integrated circuit of claim 1, wherein the processor controls the timing of the output of the PCM audio data by the transcoder.

3. The WLAN transceiving interrated circuit of claim 2, wherein the processor comprises a micro-sequencer that executes a plurality of microcode software instruction.

4. The WLAN transceiving integrated circuit of claim 1, wherein:

the processor provides a synchronization signal to the transcoder that is substantially temporally aligned with the RF slots of the WLAN interface; and

the transcoder uses the synchronization signal to output the PCM audio data so that it is substantially temporally aligned with the RF slots of the WLAN interface.

5. The WLAN transceiving integrated circuit of claim 4, wherein the processor adjusts a timing of the synchronization signal when a timing offset between the synchronization signal and a corresponding RF slot of the WLAN interface compares unfavorably to a timing offset threshold.

6. The WLAN transceiving integrated circuit of claim 4, wherein the synchronization signal comprises PCM synchronization pulses.

7. The WLAN transceiving integrated circuit of claim 1, wherein:

the WLAN interface provides a synchronization signal to the transcoder that is substantially temporally aligned with the RF slots of the WLAN interface; and

the transcoder uses the synchronization signal to output the PCM audio data so that the PCM audio data is substantially temporally aligned with the RF slots of the WLAN interface.

8. The WLAN transceiving integrated circuit of claim 1, wherein:

the transcoder produces a synchronization signal to the coupled audio CODEC that is substantially temporally aligned with the RF slots of the WLAN interface; and

the transcoder produces the PCM audio data to the coupled audio CODEC such that it is substantially synchronized with the synchronization signal.

9. The WLAN transceiving integrated circuit of claim 1, further comprising:

a CODEC operably coupled to the transcoder that converts the PCM audio data to analog audio data; and

a speaker operably coupled to the CODEC that receives the analog audio data and converts the analog audio data to an audio signal that is presented to a user.

10. The WLAN transceiving integrated circuit of claim 1, wherein the packetized audio data is in a Bluetooth Specification data format.

11. The WLAN transceiving integrated circuit of claim 1, wherein the RF slots of the WLAN interface are produced by a WLAN device transmitting to the WLAN transceiving integrated circuit.

12. The WLAN transceiving integrated circuit of claim 11, wherein:

the WLAN interface supports the Bluetooth Specification; and

the WLAN device transmitting to the WLAN transceiving integrated circuit is a master Bluetooth device of the WLAN.

13. The WLAN transceiving integrated circuit of claim 1, further comprising:

a microphone that receives an outbound audio signal from a user and tat converts the outbound audio signal to an outbound analog audio signal;

an audio CODEC operably coupled to the microphone that converts the outbound analog audio signal to outbound PCM audio data;

wherein the transcoder operably couples to the audio CODEC and converts the outbound PCM audio data to outbound packetized audio data; and

an output buffer that operably couples to the transcoder and to the WLAN interface, that receives the outbound packetized audio data from the transcoder, and tat provides the outbound packetized audio data to the WLAN interface.

14. The WLAN transceiving integrated circuit of claim 1, wherein the WLAN interface supports the Bluetooth Specification.

15. A Wireless Local Area Network (WLAN) transceiving integrated circuit that services voice communications in a WLAN with at least one WLAN device, the WLAN transceiving integrated circuit comprising:

a WLAN interface that wirelessly communicates with the at least one WLAN device to receive packetized audio data from the at least one WLAN device;

a transcoder operably coupled to the WLAN interface that receives the packetized audio data, that converts the packetized audio data to Pulse Code Modulated (PCM) audio data, and that outputs the PCM audio data to a coupled audio COder/DECoder (CODEC); and

wherein the transcoder outputs the PCM audio data to the audio CODEC such that the PCM audio data is substantially temporally aligned with Radio Frequency (RF) slots of the WLAN interface.

16. The WLAN transceiving integrated circuit of claim 15, wherein:

the WLAN interface provides a synchronization signal to the transcoder that is substantially temporally aligned with the RF slots of the WLAN interface; and

the transcoder uses the synchronization signal to output the PCM audio data so that the PCM audio data is substantially temporally aligned with the RF slots of the WLAN interface.

17. The WLAN transceiving integrated circuit of claim 15, wherein:

the transcoder produces a synchronization signal to the coupled audio CODEC that is substantially temporally aligned with the RF slots of the WEAN interface; and

the transcoder produces the PCM audio data to the coupled audio CODEC such that it is substantially synchronized with the synchronization signal.

18. The WLAN transceiving integrated circuit of claim 15, further comprising:

a CODEC operably coupled to the transcoder that converts the PCM audio data to analog audio data; and

a speaker operably coupled to the CODEC that receives the analog audio data and converts the analog audio data to an audio signal that is presented to a user.

19. The WLAN transceiving integrated circuit of claim 15, wherein the packetized audio data is in a Bluetooth Specification data format.

20. The WLAN transceiving integrated circuit of claim 15, wherein the RF slots of the WLAN interface are produced by a WLAN device transmitting to the WLAN transceiving integrated circuit.

21. The WLAN transceiving integrated circuit of claim 20, wherein:

the WLAN interface supports the Bluetooth Specification; and

the WLAN device transmitting to the WLAN transceiving integrated circuit is a master Bluetooth device of the WLAN.

22. The WLAN transceiving integrated circuit of claim 15, further comprising

a microphone that receives an outbound audio signal from a user and that converts the outbound audio signal to an outbound analog audio signal;

an audio CODEC operably coupled to the microphone that converts the outbound analog audio signal to outbound PCM audio data; and

wherein the transcoder operably couples to the audio CODEC, converts the outbound PCM audio data to outbound packetized audio data, and provides the outbound packetized audio data to the WLAN interface.

23. The WLAN transceiving integrated circuit of claim 15, wherein the WLAN interface supports the Bluetooth Specification.

24. A method for processing packetized audio data by a Wireless Local Area Network (WLAN) device that wirelessly receives the packetized audio data from another WLAN device, the method comprising:

receiving the packetized audio data from the another WLAN device;

converting the packetized audio data to Time Division Multiplexed (TDM) Pulse Code Modulated (PCM) audio data; and

outputting the PCM audio data such that the PCM audio data is substantially temporally aligned with Radio Frequency (RF) slots produced by the another WLAN device.

25. The method of claim 24, further comprising outputting a synchronization signal that is substantially temporally aligned with the RF slots of the another WLAN device.

26. The method of claim 24, further comprising:

outputting a synchronization signal that is substantially temporally aligned with the RF slots of the another WLAN device; and

outputting the PCM audio data such that the PCM audio data is substantially temporally aligned with the synchronization signal.

27. The method of claim 26, wherein the synchronization signal comprises PCM synchronization pulses.

28. The method of claim 24, wherein the packetized audio data is in a Bluetooth Specification data format.

29. The method of claim 24, further comprising:

converting the PCM audio data to analog audio data;

converting the analog audio data to an audio signal; and

presenting the analog audio signal to a user.

30. The method of claim 24, further comprising:

receiving an outbound audio signal from a user;

converting the outbound audio signal to an outbound analog audio signal;

converting the outbound analog audio signal to outbound PCM audio data;

converting the outbound PCM audio data to outbound packetized audio data; and

transmitting the packetized audio data to the another WLAN device.

31. The method of claim 24, further comprising:

outputting a synchronization signal that is substantially temporally aligned with the RF slots of the another WLAN device; and

outputting the PCM audio data such that the PCM audio data is substantially temporally aligned with the synchronization signal; and

adjusting a timing of the synchronization signal when a timing offset between the synchronization signal and a corresponding RF slot of the another WLAN device compares unfavorably to a timing offset threshold.

32. The method of claim 31, wherein the synchronization signal comprises PCM synchronization pulses.

33. The method of claim 24, further comprising:

monitoring a timing offset between the synchronization signal and a corresponding RF slot of the WLAN interface; and

when the timing offset between the synchronization signal and the corresponding RF slot of the WLAN interface compares unfavorably to a timing offset threshold, adjusting the temporal alignment of the synchronization signal.