Synchronization of Multi-Channel Audio Communicated over Bluetooth Low Energy

Apple's invention generally relates to wireless devices, and more particularly to techniques for wireless devices to communicate audio data using Bluetooth Low Energy (BLE) communications.

Apple's invention covers various methods for wireless devices to communicate audio data using Bluetooth Low Energy (BLE) and of wireless devices configured to implement the various methods.

A "low-energy audio protocol" (LEAP) is described, by which BLE devices may establish parameters of an audio data streaming session. Once a BLE capable master device and a BLE capable slave device have negotiated the various parameters (e.g., codec to be used, device types, stream directionality (e.g., input/output/bidirectional), timing/delay parameters, etc.) of the session, a "low energy audio stream" (LEAS) may be initiated between the master device and the slave device. LEAS data may then be communicated between the master device and the slave device within an overarching BLE framework.

Also described in Apple's patent filing are techniques for negotiating a codec to be used to communicate audio data using BLE. A further method presented relates to link layer timing techniques and considerations for communicating audio data using BLE. A still further method presented in Apple's patent filing relates to techniques for synchronizing audio output communicated from a master device to two slave devices using BLE. Additionally, a method is presented that relates to providing multiple slave devices with the capability to communicate non-audio data to each other via a master device using BLE audio protocol messages.

The techniques described herein may be implemented in and/or used with a number of different types of devices, including but not limited to hearing aids, remote controls, wireless speakers, set top box devices, television systems, cellular phones, and computers.

Siri/Voice Controlled Apple TV

In the most interesting example found in Apple's European patent filing was the one relating to a future version of Apple TV. Apple notes that "As another example of a possible wireless communication system, Figure 3 illustrates a system #300 in which a remote control device #304 (acting as a peripheral or slave device) is in communication with a set top box #306 (acting as a master or central device). In such an exemplary implementation, the remote control may receive audio signals (e.g., voice commands for controlling the set top box 306) from a user #302 via a microphone, and may provide audio data corresponding to those audio signals as an input audio stream to the set the top box via BLE communication.

Once the audio data is received at the set top box, Apple states that the following may be performed:

"The set top box may communicate the audio data to a server (not depicted in Figure 3) via the Internet for processing [think iCloud]; the server may analyze the received audio data and determine that the audio data corresponds to a command that can be executed by the set top box; the server may transmit one or more messages back to the set top box that indicate the command; and then the set top box may execute the command." This is definitely addressing Siri working with a future version of Apple TV.

FaceTime via Apple TV or HDTV

Alternatively or additionally, the set top box of Figure 3 may execute a videoconferencing application (FaceTime). In such a scenario, the remote control may receive audio signals from the user via a microphone, and may provide audio data corresponding to those signals as an input audio stream to the set top box via BLE communication as described in this patent filing.

Apple's filing states that upon receiving the input audio stream, the set top box may transmit the audio data to one or more other endpoints (not depicted in Figure 3) and/or intermediate servers (not depicted in Figure 3) involved in the videoconference via the Internet.

Apple further states that "As another variation on the wireless communication system of Figure 3, instead of a set top box as shown in Figure 3, the wireless communication system may include a BLE-capable television system that, in addition to performing functionality performed by a television system (e.g. rendering video data onto a display, and so on), includes components that perform the functionality described above as performed by the set top box."

This is one of the first times that Apple has outright describe "a television system that will include a real TV and the computer functionality that Apple TV has today and will have tomorrow via this new communications system that's described in Apple's European patent filing.

Wireless Hearing Aid and/or EarPod Application

Another scenario provided is one noted above in patent FIG. 2 which illustrates system #200 in which a wireless user equipment (UE) device 202 (e.g., a smart phone/iPhone, acting as a central or master device) is in communication with a pair of hearing aids #204 and #206 (acting as peripheral or slave devices).

In such an exemplary implementation, the iPhone may provide audio data (e.g., audio from a phone call, voice or video chat application, media player application, or any other audio) as an output audio stream to the hearing aids 204, 206 via BLE communication as described in Apple's patent filing.

Apple's European patent filing is miles deep and covers some of the following subject matters in much greater detail: Bluetooth Low Energy Audio Protocol Stack; - Exemplary LEAP Packet Structure and Communication Flows; Link Layer Audio Packet Format; Link Layer Packet Timing for LE Audio Transport; Coexistence Considerations with Link Layer Timing; Concurrent Communication with Multiple Slave Devices; Multiple Audio Channel Synchronization with LEA; and LEAP Passthrough.

Apple's patent which was published by the European Patent Office today, November 27, 2014, was originally filed in Q2 2014 titled Synchronization of Multi-Channel Audio over Bluetooth Low Energy. Some aspects of this patent filing used documents from 2013.

A Note for Tech Sites covering our Report: We ask tech sites covering our report to kindly limit the use of our graphics to one image. Thanking you in advance for your cooperation. 

Patently Apple presents a detailed summary of patent applications with associated graphics for journalistic news purposes as each such patent application is revealed by the U.S. Patent & Trade Office. Readers are cautioned that the full text of any patent application should be read in its entirety for full and accurate details. About Making Comments on our Site: Patently Apple reserves the right to post, dismiss or edit any comments. Comments are reviewed daily from 4am to 8pm MST and sporadically over the weekend.

New on Patently Mobile this Week

Samsung Wins Design Patents for a Round Smartwatch Band and Matching Battery Charger plus a new Bendy Smartphone