SYSTEM AND METHOD FOR REDUCING POWER CONSUMPTION IN A WIRELESS DEVICE

• US 20090017879A1
• Filed: 07/09/2008
• Published: 01/15/2009
• Est. Priority Date: 07/10/2007
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Sherman, Itay, Tsfaty, Yossi
• Granted Patent: US 8,498,678 B2
• Time in Patent Office: Days
• US Class Current: 455/574
• CPC Class Codes: H04B 1/46 by voice-frequency signals; by pilot signals
• CPC Class Codes: H04W 52/028 switching on or off only a part of the equipment circuit blocks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless transceiver is provided for transmitting and receiving audio data, comprising: a microphone configured to generate a digital audio signal that includes the audio data, based on a received sound sampled into digital format; a voice detection circuit configured to detect the presence of voice activity in the audio data, and to generate a voice detection signal indicating whether the voice activity is present in the audio data; a transceiver circuit configured to transmit the audio data over a wireless medium; and a control circuit configured to control transmission of the audio data over the wireless medium by the transceiver circuit, based on the voice detection signal. This allows saving of transmission power since no transmission is done during the silence periods. The digital audio signal is at least one of a pulse code modulated signal without compression, and a Bluetooth signal.

Claims

1. A wireless transceiver for transmitting and receiving audio data, comprising:

a microphone configured to generate a digital audio signal that includes the audio data, based on a received sound sampled into digital format;

a voice detection circuit configured to detect the presence of voice activity in the audio data, and to generate a voice detection signal indicating whether the voice activity is present in the audio data;

a transceiver circuit configured to transmit the audio data over a wireless medium;

a control circuit configured to control transmission of the audio data over the wireless medium by the transceiver circuit, based on the voice detection signal,

wherein the digital audio signal is at least one of a pulse code modulated signal without compression, and a Bluetooth signal.

2. The wireless transceiver of claim 1,

wherein the control circuit is configured to control the transceiver circuit to transmit the audio data at a first duty cycle when the voice detection signal indicates the voice activity is present in the received audio, and

wherein the control circuit is configured to control the transceiver circuit to transmit null data at a second duty cycle when the voice detection signal indicates the voice activity is not present in the received audio.

3. The wireless transceiver of claim 2, wherein the null signal is equal to a fractional portion of the silence period in the audio data.

4. The wireless transceiver of claim 1, further comprising a timer circuit configured to measure a duration when the voice detection signal indicates that the voice activity is not present in the audio data.

5. The wireless transceiver of claim 4,

wherein the control circuit is configured to control the transceiver circuit to transmit the audio data at a first duty cycle when the voice detection signal indicates the voice activity is present in the received sound, and

wherein the control circuit is configured to control the transceiver circuit to transmit null data at a second duty cycle when the timer circuit indicates that voice detection signal has indicated that the voice activity is not present in the audio data for at least a delay period.

6. The wireless transceiver of claim 5, wherein the null data is equal to a fractional portion of the audio data.

7. A method for wireless transmission of audio data, comprising:

receiving the audio data;

detecting whether voice activity has been present in the audio data over a measurement duration;

transmitting frames of the audio data at a first frame duty cycle when the voice activity is detected in the audio data over a measurement duration; and

transmitting the frames of null data at a second frame duty cycle when voice activity is not detected in the audio data over a measurement duration,

wherein the first frame duty cycle is greater than the second frame duty cycle.

8. The method of claim 7, wherein the first frame duty cycle is between 90% and 100%.

9. The method of claim 7, wherein the second frame duty cycle is between 5% and 20%.

10. The method of claim 7, wherein the second frame duty cycle provides for transmission of one of the frames of null data at least once every 100 milliseconds

11. The method of claim 7, wherein the null data is equal to a fractional portion of the audio data.

12. The method of claim 7, wherein the measurement duration is between 3 and 50 milliseconds.

13. The method of claim 7, wherein the detecting whether the voice activity has been present further comprises performing a continuous voice detection operation over a window of the measurement duration using a detection resolution smaller than the measurement duration.

14. A device for wireless transmission of audio data, comprising:

means for receiving the audio data;

means for detecting whether voice activity has been present in the audio data over a measurement duration;

means for transmitting frames of the audio data at a first frame duty cycle when the voice activity is detected in the audio data over a measurement duration; and

means for transmitting the frames of null data at a second frame duty cycle when voice activity is not detected in the audio data over a measurement duration,

wherein the first frame duty cycle is greater than the second frame duty cycle.

15. The device for wireless transmission of the audio data, as recited in claim 14, wherein the first frame duty cycle is between 90% and 100%.

16. The device for wireless transmission of the audio data, as recited in claim 14, wherein the second frame duty cycle is between 5% and 20%.

17. The device for wireless transmission of the audio data, as recited in claim 14, wherein the second frame duty cycle provides for transmission of one of the frames of null data at least once every 100 milliseconds

18. The device for wireless transmission of the audio data, as recited in claim 14, wherein the null signal is equal to a fractional portion of the audio signal.

19. The device for wireless transmission of the audio data, as recited in claim 14, further comprising means for disabling a retransmission operation when voice activity is not detected in the audio data over a measurement duration.

20. The device for wireless transmission of the audio data, as recited in claim 14, wherein the measurement duration is between 3 and 50 milliseconds.

21. The device for wireless transmission of the audio data, as recited in claim 14, wherein the means for detecting performs a continuous voice detection operation over a window of the measurement duration using a detection resolution smaller than the measurement duration.

22. A method for wireless transmission of audio data, comprising:

receiving a frame of the audio data;

determining whether voice activity has been present in the audio data over a first measurement duration;

determining whether a silent duration, during which no data has been transmitted, is greater than a second measurement duration, if the voice activity is determined not to be present in the audio data over the first measurement duration;

transmitting the frame of the audio data received using a first frame acknowledgement and retransmission protocol if the voice activity has been determined to be present in the audio data over the first measurement duration;

transmitting a null data frame using a second frame acknowledgement and retransmission protocol if the voice activity has been determined to not be present in the audio data over the first measurement duration, and the silent duration is determined to be greater than the second measurement duration; and

disabling data frame transmission and retransmission if the voice activity has been determined to not be present in the audio data over the first measurement duration, and the silent duration is determined to not be greater than the second measurement duration.

23. The method of claim 22, wherein the first measurement duration is between 3 and 50 milliseconds.

24. The method of claim 22, wherein the second measurement duration is less than 100 milliseconds.

25. The method of claim 22, wherein the null data frame is the received frame of the audio data.

26. The method of claim 22, wherein the first frame acknowledgement and retransmission protocol requires acknowledgement and allows retransmission of the received data frame.