Audio transfer using the bluetooth low energy standard

• US 9,635,493 B2
• Filed: 09/17/2014
• Issued: 04/25/2017
• Est. Priority Date: 08/19/2011
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Linde, Joakim, Tucker, Brian J.
• Primary Examiner(s): Hsieh, Ping
• Assistant Examiner(s): Jia, Xin
• Application Number:
  US14/489,090
• Publication Number:
  US 20150004913A1
• Time in Patent Office: 951 Days
• Field of Search: 455 412
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04M 1/72478 for hearing-impaired users
• CPC Class Codes: H04M 2250/02 including a Bluetooth interface
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 80/02 Data link layer protocols
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

The described embodiments include a system for communicating between electronic devices. During operation, a receiving electronic device receives a data channel protocol data unit (PDU) in a link layer of a Bluetooth Low Energy (BTLE) protocol stack. The receiving electronic device then reads a field in a header of the data channel PDU to determine if the header indicates that a payload of the data channel PDU contains audio data. When the header indicates that the payload of the data channel PDU contains audio data, the receiving electronic device is configured to send the audio data from the payload to an audio layer in the BTLE protocol stack for processing.

Claims

1. A method, comprising:

by a receiving electronic device comprising a Bluetooth Low Energy (BTLE) protocol stack, wherein the BLTE protocol stack comprises a link layer and an audio layer, the audio layer being located above the link layer within the BLTE protocol stack,

receiving a data channel protocol data unit (PDU) in the link layer of the Bluetooth Low Energy protocol stack;

by the link layer,

determining, based at least in part on a value in an LLID field in a header of the data channel PDU, whether a payload of the data channel PDU comprises encoded audio;

upon determining that the payload of the data channel PDU contains audio data, sending the audio data from the payload to the audio layer of the BTLE protocol stack for processing; and

upon determining that the payload of the data channel PDU does not contain audio data, further processing the data channel PDU based at least in part on the value in the LLID field.

2. The method of claim 1, further comprising:

from the audio layer, sending the audio data to an audio data processor in an audio subsystem in the receiving electronic device;

in the audio data processor,

performing one or more operations to generate processed digital audio data from the audio data; and

performing one or more operations to generate an analog signal from the processed digital audio data.

3. The method of claim 2, wherein sending the audio data from the audio layer to the audio data processor comprises:

determining one or more configuration settings in the receiving electronic device;

based at least in part on one or more configuration settings, determining the one or more operations to be performed to generate processed digital audio data from the audio data; and

based at least in part on one or more operations to be performed, sending the audio data from the audio layer to at least one corresponding processor in the audio data processor.

4. The method of claim 3, wherein determining the operations to be performed to generate processed digital audio data from the audio data comprises determining a type of decoder to be used to decode the audio data from the payload of the data channel PDU;

and

wherein sending the audio data from the audio layer to the corresponding processor comprises sending the audio data to the determined type of decoder for subsequent decoding.

5. The method of claim 2, wherein performing the one or more operations to generate the processed digital audio data comprises at least one of decompressing the audio data, decoding the audio data, or converting the audio data into a different format of audio data.

6. The method of claim 2, further comprising:

outputting the analog signal to at least one transducer; and

generating an output signal using the transducer.

7. The method of claim 1, wherein further processing the data channel PDU based at least in part on the value in the LLID field comprises:

forwarding the data channel PDU to an L2CAP layer of the Bluetooth Low Energy (BTLE) protocol stack;

upon determining that the data channel PDU is a configuration packet that includes information that one or more applications use in updating a configuration of at least one of the audio layer, an audio data processor in an audio subsystem, or an audio transducer, sending information from the data channel PDU to the one or more applications; and

in the one or more applications, configuring at least one of the audio layer, the audio data processor in an audio subsystem, or the audio transducer in accordance with the information from the data channel PDU.

8. The method of claim 1, wherein further processing the data channel PDU based at least in part on the value in the LLID field comprises increasing or decreasing a connection interval in the BTLE protocol stack.

9. The method of claim 1, wherein the receiving electronic device is an assistive-listening device.

10. The method of claim 1, wherein the audio layer interfaces between the link layer of the BTLE protocol stack and an audio subsystem in the receiving electronic device, wherein the audio layer forwards data received from the link layer directly to the audio subsystem for subsequent processing.

11. The method of claim 1, wherein a length of the audio data is a maximum number of bits as indicated by a length field the header.

12. The method of claim 1, wherein the audio layer comprises an audio processor and a digital-to-analog converter.

13. An electronic device, comprising:

a processing subsystem; and

a networking subsystem;

wherein the processing subsystem and the networking subsystem perform operations for;

receiving a data channel protocol data unit (PDU) in a link layer of a Bluetooth Low Energy (BTLE) protocol stack, wherein the link layer is located above an audio layer of the BLTE protocol stack, the data channel PDU having been received from a smart phone;

by the link layer,

determining, based at least in part on a value in an LLID field in a header of the data channel PDU, whether a payload of the data channel PDU comprises encoded audio; and

upon determining that the payload of the data channel PDU contains audio data, sending the audio data from the payload to the audio layer of the BTLE protocol stack for processing.

14. The electronic device of claim 13, wherein the processing subsystem and the networking subsystem further perform operations for:

from the audio layer, sending the audio data to an audio data processor in an audio subsystem in the receiving electronic device;

in the audio data processor,

performing one or more operations to generate processed digital audio data from the audio data; and

performing one or more operations to generate an analog signal from the processed digital audio data.

15. The electronic device of claim 14, wherein sending the audio data from the audio layer to the audio data processor comprises:

determining one or more configuration settings in the receiving electronic device;

based at least in part on one or more configuration settings, determining the one or more operations to be performed to generate processed digital audio data from the audio data; and

based at least in part one or more operations to be performed, sending the audio data from the audio layer to at least one corresponding processor in the audio data processor.

16. The electronic device of claim 15, wherein determining the operations to be performed to generate processed digital audio data from the audio data comprises determining a type of decoder to be used to decode the audio data from the payload of the data channel PDU;

and

wherein sending the audio data from the audio layer to the corresponding processor comprises sending the audio data to the determined type of decoder for subsequent decoding.

17. The electronic device of claim 14, wherein performing the one or more operations to generate the processed digital audio data comprises at least one of decompressing the audio data, decoding the audio data, or converting the audio data into a different format of audio data.

18. The electronic device of claim 14, wherein the processing subsystem further performs operations for:

outputting the analog signal to at least one transducer; and

generating an output signal using the transducer.

19. The electronic device of claim 18, wherein the output signal is a signal that can be perceived as sound.

20. The electronic device of claim 13, wherein further processing the data channel PDU based at least in part on the value in the LLID field comprises, by the processing subsystem and the networking subsystem performing operations for:

forwarding the data channel PDU to an L2CAP layer of the Bluetooth Low Energy (BTLE) protocol stack;

upon determining that the data channel PDU is a configuration packet that includes information that one or more applications use in updating a configuration of at least one of the audio layer, an audio data processor in an audio subsystem, or an audio transducer, sending information from the data channel PDU to the one or more applications; and

in the one or more applications, configuring at least one of the audio layer, the audio data processor in an audio subsystem, or the audio transducer in accordance with the information from the data channel PDU.

21. The electronic device of claim 13, wherein further processing the data channel PDU based at least in part on the value in the LLID field comprises increasing or decreasing a connection interval in the BTLE protocol stack.

22. The electronic device of claim 13, wherein the payload of the data channel PDU contains audio data when the value in the LLID field is 00.

23. The electronic device of claim 13, wherein the receiving electronic device is an assistive-listening device.