WO2016111643A1

WO2016111643A1 - A method for a bluetooth based communication

Info

Publication number: WO2016111643A1
Application number: PCT/SG2015/050509
Authority: WO
Inventors: Teck Chee Lee; Jie Ni
Original assignee: Creative Technology Ltd
Priority date: 2015-01-05
Filing date: 2015-12-28
Publication date: 2016-07-14
Also published as: TW201632010A

Abstract

A method for establishing a Bluetooth based communication link between an initiating device and a receiving device is provided. The initiating device can include a microphone input to receive audio signals which can be processed to produce audio data. The Bluetooth based communication link can be associated with communication parameters which include a plurality of slots. Specifically, one set of slots is reserved and another set of slots is unreserved. Additionally, the Bluetooth based communication link can be established in a manner such that audio data is communicated from the initiating device to the receiving device based on the set of reserved slots instead of the set of unreserved slots.

Description

A METHOD FOR A BLUETOOTH BASED COMMUNICATION

Field Of Invention

The present disclosure generally relates to method for establishing a Bluetooth based communication link between an initiating device and a receiving device.

Background

Bluetooth audio streaming is widely used in various applications. Examples are music streaming, wireless headset based applications.

A2DP (Advanced Audio Distribution Profile) is a typical application which supports, for example, wireless music streaming. However, A2DP suffers from latency performance (A2DP with Sub Band Codec, which is the mandatory codec, normally gives a more than 100ms delay).

To counter the issue of latency, conventional solutions include the development of low latency type codec which can be considered proprietary codec. It is appreciable that such a proprietary codec may not necessarily be supported by many, if not most, A2DP compatible Bluetooth devices. Hence issues such as incompatibility (i.e., interoperability) may render such conventional solutions ineffective/inefficient.

Summary of the Invention

In accordance with an aspect of the disclosure, a method for establishing a Bluetooth based communication link between an initiating device and a receiving device is provided. The initiating device can include a microphone input to receive audio signals which can be processed to produce audio data.

The Bluetooth based communication link can be associated with communication parameters which include a plurality of slots. Specifically, one set of slots is reserved and another set of slots is unreserved.

Additionally, the Bluetooth based communication link can be established in a manner such that audio data is communicated from the initiating device to the receiving device based on the set of reserved slots instead of the set of unreserved slots. Appreciably, the unreserved slots are typically (i.e., in a typical scenario) used in association with real-time uni-directional audio applications and the reserved slots are typically (i.e., in a typical scenario) used in association with real-time bidirectional audio applications.

Moreover, the audio data can be associated with real-time uni-directional audio applications typically (i.e., in a typically scenario) communicable via unreserved slots instead of the reserved slots.

Brief Description of the Drawings

Embodiments of the disclosure are described hereinafter with reference to the following drawings, in which:

Fig. 1 shows a system according to an embodiment of the disclosure; and

Fig. 2 shows a flow diagram of a communication method in association with the system of Fig. 1, according to an embodiment of the disclosure.

Detailed Description

Representative embodiments of the disclosure, for addressing one or more of the foregoing problems are described.

Fig. 1 shows a system 100 in accordance with an embodiment of the disclosure. The system 100 can include an initiating device 110 and a receiving device 120. The initiating device 110 can be coupled to the receiving device 120 in a manner such that the initiating device 110 and the receiving device 120 can communicate with each other.

Preferably, communication between the initiating device 110 and the receiving device 120 is based on wireless communication. Wireless communication between the initiating device 110 and the receiving device 120 can be in the form of Bluetooth based communication. In this regard, a Bluetooth based communication link 130 between the initiating device 110 and the receiving device 120 can be established in a manner such that the initiating device 110 and the receiving device can signal communicate with each other.

The initiating device 110 can include an input portion 110a and a communication portion 110c. As an option, the initiating device 110 can further include a processing portion 110b. In one embodiment, the input portion 110a can be coupled to the communication portion 110c. In another embodiment, the input portion 110a can be coupled to the processing portion 110b and the processing portion 110b can be coupled to the communication portion 110c. In yet another embodiment, the input portion 110a can be coupled to the processing portion 110b and the communication portion 110c, and the processing portion 110b can be coupled to the communication portion 110c.

The input portion 110a can be configured to receive audio signals and process the audio signals to produce audio data. The input portion 110a can, for example, be a receiving device such as a microphone input for receiving audio signals. For example, a user (not shown) of the system 100 can be speaking into the microphone input and the microphone input can be configured to receive voice signals from the user. In this regard, the voice signals received by the microphone input can correspond to audio signals received by the microphone input. The microphone input can process the received audio signals to produce audio data which can be communicated to the processor portion 110b and/or the communication portion 110c for further processing. Specifically, the input portion 110a can process the received audio signals in a manner so as to produce audio data which can be suitable for one or both of further processing by the processing portion 100b and further processing by the communication portion 110c.

The processing portion 110b can be configured to receive and process the audio data to produce processed audio data. The processing portion 110b can, for example, be an audio processor configured to perform audio based processing on the audio data. Examples of audio based processing can include Equalizer (EQ) processing, audio effects processing such as reverberation and/or vocal enhancements processing such as automatic pitch correction and backup singers harmonizing effect. In this regard, the processing portion 110b can be configured to perform, for example, any of EQ processing, audio effects processing and vocal enhancements processing, or any combination thereof, on audio data to produce processed audio data. Processed audio data can be communicated from the processing portion 110b to the communication portion 110c.

The communication portion 110c can be configured to receive and process one or both of audio data the processed audio data to produce output signals which can be communicated to the receiving device 120. The communication portion 110c can be further configured to establish a communication link between the initiating device 110 and the receiving device 120. In this regard, the communication portion 110c can, for example, correspond to a transceiver configurable to establish a communication link between the initiating device 110 and the receiving device 120. Moreover, the output signals can be in a form suitable for communication via the communication link. Earlier mentioned, communication between the initiating device 110 and the receiving device 120 is preferably based on wireless communication and wireless communication can be in the form of Bluetooth based communication. In this regard, the communication portion 110c can, for example, correspond to a Bluetooth based transceiver configured to establish the Bluetooth based communication link 130 and the processed audio data can be processed by the communication portion 110c to produce output signals which are suitable for Bluetooth based communication via the Bluetooth based communication link 130.

The output signals can be communicated from the initiating device 110 to the receiving device 120 via the Bluetooth based communication link 130.

In this regard, it is appreciable that the receiving device 120 can include a communication module (not shown) analogous to the communication portion 110c. The communication module can communicate with the communication portion 110c so as to establish the communication link (e.g., Bluetooth based communication link 130) between the initiating device 110 and the receiving device 130.

The receiving device 130 can be configured to process the received output signals so as to produce information signals which can be output from the receiving device 130 in a manner so that the information signals is, for example, audibly perceivable by a listener (not shown). In this regard, the receiving device 130 can include one or more speaker drivers (not shown) for providing an output of the information signals.

Earlier mentioned, the output signals can be communicated from the initiating device 110 to the receiving device 120 via the Bluetooth based communication link 130. Communication of the output signals via the Bluetooth based communication link 130 will now be discussed in further detail hereinafter.

In general, there are different types of logical transports defined in Bluetooth based communication. One type is logical transport associated with reserved slots and another type is logical transport associated with unreserved slots (i.e., without reserved slots). Logical transport associated with reserved slots can be referred to as synchronous logical transport whereas logical transport associated with unreserved slots can be referred to as asynchronous logical transport.

Synchronous logical transport (SCO/eSCO logical transport) is a point to point type logical transport between two devices (e.g., between a master device and a slave device). For synchronous logical transport, synchronous links can be established between the master device and the slave device. The synchronous links allow the Bluetooth piconet clock to be associated with transported data (i.e., data communicated between the master device and the slave device). Specifically, regular slots on the communication channel (e.g., the communication link) between the master device and the slave device can be reserved and fixed sized data packets (i.e., transported data/data to be transported) can be communicated (e.g., from the master device to the slave device) via communication channel via the reserved regular slots. Synchronous logical transport can be characterized as a low latency communication link (compared to asynchronous logical transport) and data transported via the synchronous logical transport can be considered to be associated with low latency. Therefore, synchronous logical transport is typically used in association with real-time bidirectional audio applications (e.g., phone call related real-time bidirectional audio applications) which may considered to be time critical and when low latency is desired.

On the other hand, asynchronous logical transport can be associated with asynchronous links being established between two devices (e.g., a master device and a slave device). In this regard, data transported between the master device and the slave device can be considered to be without any time based characteristics (unlike SCO/eSCO logical transport which can be based on the Bluetooth piconet clock). Data to be transported (e.g., from the master device to the slave device) is expected to be retransmitted (assuming failure to transmit has occurred) until data to be transported is successfully received (e.g., at the slave device). Additionally, received data need not necessary be processed based on time of receipt. Asynchronous logical transport can be characterized as a high/higher latency communication link (compared to synchronous logical transport) and data transported via the asynchronous logical transport can be considered to be associated with high latency. Therefore, asynchronous logical transport is typically used in association with real-time unidirectional audio applications (e.g., music streaming, wireless headset and/or wireless microphone related applications). Specifically, such applications are typically non bi-direction type applications (i.e., only uni-direction) which may not be considered to be time critical (i.e., in the sense that received data need not necessary be processed based on time of receipt). In this regard, it is appreciable that the Bluetooth based communication link 130 can be associated with communication parameters which can include a plurality of slots. The plurality of slots can include one set of slots which is reserved (i.e., synchronous logical transport) and another set of slots which is unreserved (i.e., asynchronous logical transport). Additionally, the Bluetooth based communication link 130 is established in a manner such that audio data is communicated from the initiating device 110 to the receiving device 120 based on the set of reserved slots instead of the set of unreserved slots.

Appreciably, for the system 100, audio data can be based on audio signals received by the input portion 110a which can, for example, be a microphone input. Therefore, the initiating device 110 can, for example, correspond to a wireless microphone device. As noted earlier, asynchronous logical transport (i.e., unreserved slots) is typically used in association with applications such as wireless microphone/music streaming related applications. Specifically, the unreserved slots (also referable as asynchronous logical transport) are typically used in association with real-time unidirectional audio applications and the audio data is considered to be associated with real-time unidirectional audio applications typically communicable via unreserved slots. Hence it is clear that a skilled artisan in Bluetooth based communication would typically consider the use of unreserved slots for the communication of the aforementioned audio data and/or processed audio data and attempt to overcome the issue of latency by use of, for example, low latency codec since synchronous logical transport is typically used in association with, for example, phone call related real-time bidirectional audio applications.

The present disclosure contemplates the possibility of utilizing reserved slots (i.e., which can be characterized as a low latency communication link) for the communication of the output signals (i.e., based on audio data and/or processed audio data) from the initiating device 110 instead of unreserved slots. Moreover, the present disclosure contemplates that the use of synchronous logical transport (also referable as reserved slots) for communication of the output signals (i.e., based on audio data and/or processed audio data which can be associated with real-time unidirectional audio applications and which a skilled artisan would understand to be typically communicated via asynchronous logical transport - a typical scenario) between the initiating device 110 and the receiving device 120 in view of communication compatibility since synchronous logical transport can be considered a standard logical transport in Bluetooth based communication (and therefore compatible with Bluetooth based devices that support synchronous logical transport type communication). Therefore, the present disclosure provides a solution for overcoming latency issues associated with communication of audio data and/or processed audio data from the initiating device 110 and, at the same time, avoid interoperability issues (i.e., communication compatibility can be maintained) encountered by conventional solutions such as the aforementioned low latency codec. Moreover, since the reserved slots (i.e., synchronous logical transport) can be considered to be a standard logical transport and readily available for use, there is no need to devise proprietary type solutions (e.g., low latency codec) which may be complicated and may not be effective (e.g., due to interoperability issues).

The system 100 will be discussed in further detail based on an exemplary operation hereinafter.

The initiating device 110 can be configured to communicate a request (e.g., in the form of a setup message signal) to the receiving device 120. The communicated request can be to establish a logical transport type (e.g., synchronous logical transport) for communication between the initiating device 110 and the receiving device 120. The communicated request can be further to negotiate any configuration parameters so as to match the unidirectional throughput requirements of, for example, the output signals (e.g., video codec, audio data, processed audio data) communicable from the initiating device 110 to the receiving device 120. For example, the synchronous logical transport can be established by the initiating device 110 by communicating a setup message signal via a Link Manager (LM) protocol. The setup message signal (i.e., the request) can contain information such as timing parameters (i.e., configuration parameters) to specify the reserved slots.

The receiving device 120 may be configured to accept or reject the communicated request from the initiating device 110. In one example, the receiving device 120 may choose to reject the communicated request (e.g., by communicating a rejection signal to the initiating device 110). In another example, the receiving device 120 may choose to accept the communicated request (e.g., by communicating an acceptance signal to the initiating device 110). In yet another example, the receiving device 120 may choose to accept the communicated request but counter ((e.g., by communicating a counter configuration signal to the initiating device 110) the request with a different set configuration parameters from that requested by the initiating device 110.

In the case(s) where a rejection signal and/or a counter configuration signal is/are communicated from the receiving device 120 to the initiating device 110, the initiating device 110 can be configured to resend another request (e.g., in the form of a retry signal) with a different set of configuration parameters (e.g., also with the aim of the aforementioned matching of unidirectional throughput requirements). Thus it is appreciable that there is some form of negotiation between the initiating device 110 and the receiving device 120 (for establishing the logical transport type and/or for establishing configuration parameters that match). For example, the configuration parameters may include a latency parameter which specifies an upper limit to the time (e.g., in milliseconds) interval between transport instants (e.g., time interval between the transport of a fixed sized data packet and the transport of another fixed sized data packet). Should there be a possibility that the latency parameter will cause a latency violation (i.e., latency is greater than the maximum allowed latency), a rejection signal and/or a counter configuration signal can be communicated from the receiving device 120 to the initiating device 110 and the initiating device 110 can communicate another request proposing new parameters that will not cause latency violation.

In the case where an acceptance signal is communicated from the receiving device 120 to the initiating device 110, the communication link (e.g., the Bluetooth based communication link 130) can be considered to have been successfully established. For example, when the configuration parameters are deemed acceptable by both the initiating device 110 and the receiving device 120, the Bluetooth based communication link 130 is successfully established. In this case, the initiating device 110 can start communicating (i.e., transporting), for example, the fixed sized data packets (e.g., in the form of output signals) to the receiving device 120 at regular time intervals (i.e., based on the negotiated configuration parameters between the initiating device 110 and the receiving device 120) via the reserved slots. Hence a unidirectional (from the initiating device 110 to the receiving device 120) low latency communication link between the initiating device 110 and the receiving device 120 can be established for communication of the output signals via the reserved slots.

Referring to Fig. 2, a flow diagram of a communication method 200 in association with the system 100 is shown, in accordance with an embodiment of the disclosure.

The communication method 200 can correspond to a method for establishing a Bluetooth based communication link 130 between the initiating device 110 and the receiving device 120. The method can include a source step 210 and a connection step 220. In the source step 210, audio signals can be received and processed to produce audio data. Specifically, the initiating device 110 can include a microphone input (i.e., the input portion 110a) to receive audio signals which can be processed to produce audio data. The audio signal can be processed by the microphone input to produce audio data.

In the connection step 220, Bluetooth based communication link 130 between the initiating device 110 and the receiving device 120 can be established. Earlier mentioned, the Bluetooth based communication link 130 can be associated with communication parameters which include a plurality of slots. Specifically, one set of slots is reserved and another set of slots is unreserved. Specifically, the Bluetooth based communication link 130 can be established in a manner such that audio data is communicated from the initiating device 110 to the receiving device 120 based on the set of reserved slots instead of the set of unreserved slots.

The connection step 220 can further include a configuration step (not shown). In regard to the configuration step, the initiating device 110 can be configured to communicate a request (e.g., in the form of a setup message signal) to the receiving device 120. Earlier mentioned, the communicated request can be to establish a logical transport type (e.g., synchronous logical transport) for communication between the initiating device 110 and the receiving device 120. Also earlier mentioned, the communicated request can be further to negotiate any configuration parameters so as to match the unidirectional throughput requirements of, for example, the output signals (e.g., video codec, audio data, processed audio data) communicable from the initiating device 110 to the receiving device 120.

In the foregoing manner, various embodiments of the disclosure are described for addressing at least one of the foregoing disadvantages. Such embodiments are intended to be encompassed by the following claims, and are not to be limited to specific forms or arrangements of parts so described and it will be apparent to one skilled in the art in view of this disclosure that numerous changes and/or modification can be made, which are also intended to be encompassed by the following claims.

Claims

1. A method for establishing a Bluetooth based communication link between an initiating device having a microphone input to receive audio signals processable to produce audio data and a receiving device, the Bluetooth based communication link being associable with communication parameters comprising a plurality of slots wherein one set of slots is reserved and another set of slots is unreserved, the Bluetooth based communication link being established in a manner such that audio data is communicated from the initiating device to the receiving device based on the set of reserved slots instead of the set of unreserved slots.

2. The method as in claim 1,

wherein the unreserved slots are typically used in association with real-time uni-directional audio applications,

wherein the reserved slots are typically used in association with real-time bidirectional audio applications, and

wherein the audio data is associated with real-time uni-directional audio applications typically communicable via unreserved slots.