JP2021153304A - New method of wireless transmission of digital audio - Google Patents

Abstract

To enable stereo synchronization between two paired audio sinks (such as hearing aids).SOLUTION: There is provided a method in compliance with a Bluetooth Low Energy (LE) standard. The method comprises: transmitting a first data set with a first priority; in absence of an acknowledgement of receipt, re-transmitting the first data set with the first priority; and in presence of the acknowledgement of receipt, transmitting a second data set with a second priority that is lower than the first priority when a transmitter and receiver would have been connected for the re-transmission in absence of the acknowledgement.SELECTED DRAWING: Figure 5

Description

A new method of wirelessly communicating data with different priorities is provided, for example, in conformity with the Bluetooth Low Energy (LE) standard. New auditory devices configured to be suitable for wireless communication by new methods are also provided.

Bluetooth LE, defined in the Bluetooth Core Specification 4.1 or earlier, does not allow audio transmission. The as-defined protocol has some limitations, which means that audio transmission is not feasible without changing some protocol layers.
-The nature of the L2CAP channel defined for LE, which defines a best-effort data transmission method that does not use timeouts or flashes when transmitting, is also a real-time audio via the LE as defined. It means that it is almost impossible to provide services.
-The lack of real-time transmission means that stereo synchronization between two paired audio sinks (such as hearing aids) is almost impossible.
-Packet size means that the overhead of transmitting the data rate required for audio (typically 32 to 48 kbit / s) is very high.

Overcoming the above drawbacks is the goal of new methods and hearing devices.

A new method of wirelessly communicating data sets is provided, including:
a) The step of transmitting the first data set of the first data category from the transmitting device to the receiving device for receiving.
b) The step of retransmitting the first data set if there is no acknowledgment of reception from the receiver.
c) If there is an acknowledgment of reception from the receiver, then when the transmitter and receiver are connected for retransmission, for example, the first data set in the first data category. The step of transmitting a second data set of a second data category different from the first data category from the transmitting device to the receiving device within the same connection event in which the was transmitted.

In addition, a novel method of wirelessly communicating data having different priorities, including the following, is provided.
a) A step of transmitting a first data set of first priority from a transmitting device to a receiving device for receiving.
b) The step of retransmitting the first data set of first priority if there is no acknowledgment of reception from the receiver.
c) If there is an acknowledgment of reception from the receiver, otherwise the transmitter and receiver have a second priority lower than the first priority when connected for retransmission. The step of transmitting a second data set from the transmitting device to the receiving device.

The first data category may include audio data sets.

The second data category includes various control data such as start, stop, codec negotiation, and / or based on the Bluetooth LE standard protocol as defined in the Bluetooth Core Specification 4.1 or earlier. Alternatively, it may include data from another device, eg, a device equipped with a sensor such as an environmental sensor such as a temperature sensor.

The first data set may be an audio data set. The audio data set contains digital audio signal values such as a series of discrete time and discrete amplitude digital audio signal values, and a series of discrete time and discrete amplitude digital audio signal values are of analog audio signals. It represents a continuous time and continuous amplitude value, and its analog audio signal can be converted into sound. In other words, as is well known in the technical field of streaming audio, an audio data set includes digital data that is intended to be converted into sound at some point.

Preferably, the audio data set has a high priority and a lower priority to ensure high fidelity or at least acceptable quality of the sound produced based on the transmitted audio data set. Ensure transmission of the audio data set before transmitting other types of data sets with degree.

The data set, including the audio data set, can be a data packet having two types of data, namely control information and data. The data is also known as payload or payload data. The control information provides informational data that the network needs to deliver the data or payload to the intended receiver, such as source and destination device addresses, error detection codes, and sequence control information. Typically, control information is found in the packet header and trailer, with payload data in between.

The method may further include:
d) A step of signaling from a transmitter to a receiver as to whether a data set with a second priority is waiting to be transmitted to the receiver.
e) Between a transmitter and a receiver for transmission of a second data set with a second priority if there is no data set with a second priority waiting to be transmitted to the receiver. Steps to stop establishing a connection.

Information about whether a data set with a second priority is waiting to be transmitted to the receiving device may be encoded in a single data byte, such as a single data bit.

The method may comply with Bluetooth Low Energy standards, such as Bluetooth Core Specification 4.1 or earlier, preferably within continuous connection events when transmitting audio data sets. Will be implemented.

This method may be used, for example, for audio streaming of audio and music in a form conforming to Bluetooth Low Energy standards such as Bluetooth Core Specification 4.1 or earlier versions.

The method may further include assigning an L2CAP channel to the transmission of an audio data set, eg, assigning one L2CAP channel to control data associated with an audio data set and / or 1 One L2CAP channel may be assigned to the first audio data set and another L2CAP channel may be assigned to the second audio data set if possible.

The following three fixed L2CAP channels may be assigned to audio transmission.
1) Control data (start, stop, codec negotiation, etc.)
2) Left audio data 3) Right audio data

Only devices capable of receiving one audio stream (left or right), such as hearing aids, will be used in the device: channels 1) and 2), or channels 1) and 3). Devices with integrated stereo capabilities, such as stereo headsets, use all three channels. The audio data set may be unidirectional or bidirectional, depending on the field of application, and the control data channel should allow negotiation in that regard.

The connection configuration may be performed by, for example, the following procedure.
1. 1. The receiving device is informed through a unique UUID that it can receive prioritized flushable L2CAP (PFL2CAP) data.
2. The transmitting device discovers the receiving device, connects to the receiving device, and inquires of the PFL2CAP service about its function.
3. 3. The receiver responds with a PFL2CAP configuration. For audio, for example, this includes which codec the receiver provides and which content the receiver intends to receive on which L2CAP channel with which priority, eg (channel 127, high priority, left side). (Audio), (Channel 128, high priority, right side audio), and (Channel 129, low priority, audio control information) may be included.
4. The transmitting device acknowledges the reception by transmitting additional information about the data, such as content, codec and frame size, flash timeout, and so on.
5. Both the transmitter and receiver set up a new L2CAP channel, prepare the audio stream, and adjust the connection rate to match the product of the specified frame rate multiplied by the number of retransmissions.

For example, the operation of the transmitter while streaming audio may include the following:
1. 1. The host of the transmitter controller starts processing the audio stream, encodes the first audio frame, and processes it to be queued for immediate transmission on the specified L2CAP channel (s). .. The host then moves on to processing the next audio frame.
2. At the same time, the control layer attempts to send the packets in priority order. As soon as the transmission is successful, the control layer notifies the success and requests the next packet from the host. If a packet is flushed due to a timeout, the control layer notifies the failure and also requests the next packet.
3. 3. Audio control information from the host, such as volume changes, is queued within the specified L2CAP channel. The controller sends the packet when there are no higher priority transmit packets in the waiting state.

The method further states that in the absence of an acknowledgment of reception from the receiver of the audio data set, the number of attempts to retransmit the same audio data set is less than a predetermined maximum, for example equal to 2. The condition may include the retransmission of the audio data set.

The number of attempts to retransmit one or more types of data may not be limited, i.e. no maximum is assigned to one or more types of data, or in other words, one. Or the maximum value assigned to a plurality of types of data is infinite, for example 0xFFFF.

Different types of data may have different predetermined maximum values for retransmission attempts, for example, an audio data set can have a maximum value of 2, while being lower than the priority of the audio data set. The maximum value of the data set that has the priority.

For example, the novel method can implement an L2CAP flash timeout, which is also defined in the Bluetooth Basic Rate (BR) L2CAP channel. Preferably, this timeout corresponds to two connection events for the channel carrying the audio data after the data has been posted via HCI (ie, allowing a first retry event for L2CAP audio). On the other hand, it stays at 0xFFFF for other channels.

On a typical link, packets can be lost at a rate that is not suitable for audio. Therefore, it is preferably retransmitted, preferably on different channels. Therefore, the MD function of Bluetooth LE cannot be used for retransmission. Therefore, an audio data set with a flash timeout should simply be tried once within the connection interval. To allow retransmission, the connection interval should be half the audio frame size, so if the audio frame is 10ms, the connection interval should be 5ms. This is facilitated using existing link layer control packets.

The MD function may be used to transmit low priority data within the same connection event, but the receiver may not accept the MD bit, for example, the hearing aid will not accept the MD bit.

To reduce the power consumption of the receiving device, the transmitting device indicates that there is low priority data in the waiting state regardless of whether or not the data is transmitted within the same connection event after the high priority data. Therefore, the MD bit may be set in the high priority packet. If there is no low priority data in the waiting state, the MD bit is reset. This allows the receiving device to skip dataless connection events between successful transmissions of high priority audio data sets in response to the value of the received MD bits. Similarly, transmitters may skip waiting dataless connection events during audio streaming to save power and / or increase interoperability with other wireless services. It is possible.

Note that when transmitting a non-audio data set, without the L2CAP flash timeout, the link will be occupied until an acknowledgment is given to the data. This rarely causes audio dropouts, which must be addressed by packet loss concealment on the receiving side, as disclosed, for example, in EP26055547A1.

The method further comprises between at least two different receivers connected to receive different audio data sets from the transmitter to at least one receiver configured to receive the audio data set. It may include transmitting synchronous data including timing information related to the transmission delay difference of.

The determination of the synchronization data may be based on ping transmission from the transmitting device to at least two different receiving devices, such as ping transmission utilizing the L2CAP control channel.

Preferably, during stereo audio streaming, the transmitter transmits the time offset between the links to the preceding receiver in the link, thereby delaying the received audio accordingly and the two stereos. Channels can be properly synchronized. The time offset can be determined using network latency measurements that perform pings via the control channel. This ping allows the sending host to calculate the time offset.

Stereo audio streaming can also be performed using a single link. For example, while stereo audio streaming to headphones, both the left L2CAP channel and the right L2CAP channel may be transmitted using the same link, thereby keeping both the receiver and transmitter simple. Will be done. Headphones can withstand higher radio duty cycles, so the MD functionality of Bluetooth LE may be utilized for this purpose. In this way, the same connection event can convey information about both the left and right channels, and the packet structure can be kept the same as in mono or dual sync. This simplifies implementation on both sides. This is because only the audio connection handle needs to be changed on the sending host side compared to the dual sync case.

The table below outlines the number of bytes required to hold an audio data set given a particular audio frame size in ms. These values are for audio streams flowing at 48 kbit / s. For a 32 kbit / s audio stream, this is two-thirds of this requirement.

To minimize overhead, the MTU size of the LL should be matched to the MTU of the L2CAP plus the header and MIC so that the method or controller that implements the L2CAP audio preferably accommodates long packets. And it is preferable to make it equal to the required payload size.

Advantageously, the new method facilitates the transmission of audio data sets using Bluetooth LE by utilizing limited form of Bluetooth LE controls and link layer extensions, eg, for example. Actions related to security and link setup are performed as specified in the Bluetooth Core specification.

Hearing devices with communication controllers configured to be suitable for operation by the novel method described in any of the appended claims are also provided.

Hearing aids include hearing aids such as BTE, RIE, ITE, ITC, and CIC, binaural hearing aids, ear hook type, in ear type, on ear type, over ear type, behind neck type, helmet type, and head guard. Headsets such as molds, headphones, earphones, ear defenders, ear muffs, etc. may be used.

Preferably, the communication controller is configured to be suitable for audio transmission and / or audio reception using Bluetooth LE L2CAP, and preferably the communication controller is.
-Corresponds to L2CAP flash timeout = 2-Corresponds to L2CAP traffic with priority-Configures to accommodate LL packet sizes up to 120 bytes, depending on bit rate and audio frame size selection Will be done.

Therefore, a new hearing aid capable of performing wireless communication in accordance with the Bluetooth LE standard protocol is provided.

New hearing aids
An input transducer configured to output an audio signal based on the sound-representing signal given to it, and a hearing loss-compensated audio signal for the user of the hearing aid. For example, in this hearing aid, the sound volume of a given signal that a normal hearing person perceives is the sound of a hearing loss-compensated signal that the user perceives. Handset, embedded type, which can be aimed at regaining the loudness of the sound so that it almost matches the loudness, and is configured to output an auditory output signal based on an audio signal compensated for hearing loss. An output transducer, such as a transducer, may be provided with an output transducer and a communication controller that allow the human auditory system to receive its auditory output signal so that the user can hear sound.

A transducer is a device that converts a signal given to a transducer in the form of one energy into an output signal in the corresponding form of another energy.

The input transducer can be equipped with a microphone, which converts the acoustic signal given to the microphone into a corresponding analog audio signal whose instantaneous voltage fluctuates continuously with the sound pressure of the acoustic signal. do.

The input transducer may include a telecoil. The telecoil converts the fluctuating magnetic field in the telecoil into a fluctuating analog audio signal, which is a corresponding analog audio signal in which the instantaneous voltage fluctuates continuously with the fluctuating magnetic field strength in the telecoil. Telecoil is a voice from a speaker speaking to multiple people, for example, in public places such as churches, public halls, theaters, cinemas, or through public address systems such as stations, airports, shopping malls, etc. It can be used to increase the signal-to-noise ratio. The voice from the speaker is converted into a magnetic field using an induction loop system (also called a "hearing loop"), and a telecoil is used to magnetically pick up the magnetically transmitted voice signal.

The input transducer may further include a beamformer configured to combine at least two isolated microphones and the microphone output signals of at least two isolated microphones into a directional microphone signal.

The input transducer includes one or more microphones, a telecoil, and a switch for selecting, for example, an omnidirectional microphone signal, or a directional microphone signal, or a telecoil signal, alone or in any combination, as an audio signal. May be provided.

Typically, an analog audio signal is converted to the corresponding digital audio signal in an analog-digital converter, thereby expressing the amplitude of the analog audio signal in binary for digital signal processing. It will be suitable. In this way, a discrete-time and discrete-amplitude digital audio signal in the form of a series of digital values represents a continuous-time and continuous-amplitude analog audio signal.

Throughout the disclosure, the "audio signal" may be used to identify any analog or digital signal that forms part of the signal path from the output of the input transducer to the input of the hearing loss processor.

Throughout this disclosure, a "hearing loss compensated audio signal" is an arbitrary that forms part of the signal path from the output of a hearing loss processor to, in some cases, via a digital-to-analog converter, to the input of an output transducer. Can be used to identify analog or digital signals.

Hearing aids can include transceivers that include both wireless transmitters and wireless receivers. The transmitter and receiver may share a common circuit and / or a single housing. Alternatively, the transmitter and receiver do not have to share a circuit, and the wireless communication unit may have separate devices, each with a transmitter and a receiver.

Hearing aids advantageously utilize the Bluetooth LE standard protocol, for example, for two hearing aids to digitally exchange data such as audio signals, signal processing parameters, control data such as signal processing program identifiers, etc. It may be interconnected and optionally incorporated into a binoral hearing aid system that is interconnected with other devices such as tablet computers, smartphones (eg Bluetooth, Android phones, Windows phones, etc.), handheld devices such as remote controls. ..

Typically, only a limited amount of power is available from the hearing aid power source. For example, power is typically supplied by a _{conventional ZnO 2 battery in a hearing aid.}

When designing a hearing aid, size and power consumption are important considerations.

Signal processing in new hearing aids may be performed with dedicated hardware, or with one or more signal processors, or with dedicated hardware and one or more signal processors. It may be carried out in the combination of.

Similarly, the operation of the communication controller may be performed by dedicated hardware, may be performed by one or more processors, or may be performed by a combination of dedicated hardware and one or more processors. It may be carried out.

As used herein, the terms "processor," "signal processor," "controller," "system," etc. are CPU-related to either hardware, a combination of hardware and software, software, or running software. It shall refer to the entity of.

For example, "processor", "signal processor", "controller", "system", etc. are, but are not limited to, processes, processors, objects, executables, threads of execution, etc. that are executed on the processor. And / or may be a program.

As an example, terms such as "processor," "signal processor," "controller," and "system" refer to both applications and hardware processors running on the processor. One or more "processors", "signal processors", "controllers", "systems", etc., or any combination thereof, may be present within a thread of process and / or execution. Multiple "processors", "signal processors", "controllers", "systems", etc., or combinations of any of these, in some cases combined with other hardware circuits, are centralized on a single hardware processor. And / or, in some cases, in combination with other hardware circuits, may be distributed among two or more hardware processors.

Also, the processor (or similar term) may be any component capable of performing signal processing, or any combination of such components. For example, the signal processor may be an ASIC processor, an FPGA processor, a general purpose processor, a microprocessor, a circuit component, or an integrated circuit.

In the following, the novel method and hearing aid will be described in more detail with reference to the drawings.

It is a diagram schematically showing a binaural hearing aid system that receives audio streaming from a smartphone according to a new method. It is a figure schematically showing an example of transmitting an audio data set according to a novel method. FIG. 5 schematically illustrates another example of transmitting an audio data set according to a novel method. FIG. 5 schematically illustrates another example of transmitting an audio data set according to a novel method. FIG. 5 schematically illustrates another example of transmitting an audio data set according to a novel method. FIG. 5 schematically illustrates another example of transmitting an audio data set according to a novel method. FIG. 5 schematically illustrates another example of transmitting an audio data set according to a novel method. It is a flow chart of an example of a new method. It is a flow chart of another example of a new method. It is a flow chart of another example of a new method. It is a flow chart of another example of a new method.

The following are new methods and various examples of hearing devices. However, the novel methods and hearing devices described in the appended claims can be implemented in a variety of ways and should not be construed as being limited to the examples described herein.

Please note that the accompanying drawings are schematic and simplified for readability and provide only essential details for understanding new methods and hearing aids, excluding other details.

Similar reference numbers refer to similar elements throughout. Therefore, the same elements will not be described in detail with respect to the description of each figure.

FIG. 1 schematically shows a binal hearing aid system including a left ear hearing aid 10L and a right ear hearing aid 10R, where the left ear hearing aid 10L and the right ear hearing aid 10R are smartphones or mobile phones, audio-enabled tablets, cordless phones, and television receivers, respectively. It is equipped with a wireless communication unit so that it can be connected to another audio-compatible communication device such as a machine. In the present embodiment, the left ear hearing aid 10L and the right ear hearing aid 10R are connected to the smartphone 50 via the corresponding wireless communication links 12L and 12R, respectively. Those skilled in the art will appreciate that in other embodiments of the system where the right hearing aid 10R is optional, the binaural hearing aid system may include only a single hearing aid, such as the 10L.

A unique ID identifies every device in the binaural hearing aid system. The illustrated binaural hearing aid system is configured to operate in general according to, for example, Bluetooth Low Energy (Bluetooth LE) corresponding to Bluetooth Core Specification Version 4.1. Therefore, the illustrated binoral hearing aid system is configured to operate in the 2.4 GHz Industrial Science and Medical (ISM) band according to Bluetooth LE and includes 80 frequency channels with a 1 MHz bandwidth. However, as described in more detail below, the Bluetooth LE controller of the wireless communication unit of the left ear hearing aid 10L and the right ear hearing aid 10R, respectively and the smartphone 50 is a real-time audio audio through the wireless communication links 12L, 12R, respectively. It has been modified to allow the transmission of data sets.

The left hearing aid 10L and the optional right hearing aid 10R may be substantially identical and can be expected for the unique IDs described above, therefore the following description of the features of the left hearing aid 10L will be in the right hearing aid 10R. Also applies. The left hearing aid 10L may include a ZnO ₂ battery (not shown) connected to power the hearing aid circuit 14. The left hearing aid 10L comprises an input transducer in the form of a microphone 16. When the left hearing aid 10L is in operation, the microphone 16 outputs an analog or digital audio signal based on the acoustic signal reaching the microphone 16. When the microphone 16 outputs an analog audio signal, the hearing aid circuit 14 converts the analog audio signal into the corresponding digital audio signal so that it can be digitally processed within the hearing aid circuit 14. A converter (not shown) may be provided. Specifically, it may be provided in the hearing loss processor 24L configured to compensate for the hearing loss of the user of the left hearing aid 10L. Preferably, the hearing loss processor 24L comprises a dynamic range compressor well known in the art by compensating for frequency-dependent loss of the user's dynamic range, often referred to in the art as a replenishment phenomenon. Therefore, the hearing loss processor 24L outputs the hearing loss compensated audio signal to the loudspeaker or the handset 32. The loudspeaker or handset 32 converts the hearing loss-compensated audio signal into the corresponding acoustic signal and sends it out toward the user's eardrum. Therefore, the user hears the sound reaching the microphone, but compensated for the user's individual hearing loss. In the hearing aid, the loudness of the sound of the hearing loss-compensated signal perceived by the user wearing the hearing aid 10 reaches the microphone 16 as perceived by a listener having normal hearing. It may be configured to regain loudness so that it closely matches the tone.

The hearing aid circuit 14 further includes a wireless communication unit comprising a wireless unit or a wireless circuit 34L configured to wirelessly communicate with the smartphone 50. The wireless communication unit comprises a Bluetooth LE controller 26L that performs various communication protocol related tasks and possibly other tasks. The operation of the left hearing aid 10L can be controlled by an appropriate operating system. The operating system manages the hardware and software resources of the hearing aid, including, for example, the hearing loss processor 24L and other possible processors and associated signal processing algorithms, wireless communication units, some memory resources, etc. It may be configured in. The operating system may schedule tasks to make efficient use of hearing aid resources, and costs, including power consumption, processor time, storage location, wireless transmission, and other resources. It may include accounting software for assigning.

The operating system controls the wireless circuit 34L to perform wireless communication with the smartphone 50 according to the Bluetooth LE protocol, which has been modified to support audio. In connection with bidirectional data communication between devices based on the modified Bluetooth LE protocol, the smartphone 50 may operate as a master device and the left hearing aid 10L may operate as a slave.

The smartphone 50 includes a radio unit or radio circuit 54 configured to wirelessly communicate with the corresponding radio unit or radio circuit 34L of the left hearing aid 10L. The smartphone 50 also includes a wireless communication unit, which comprises a Bluetooth LE controller 56 that performs various communication protocol related tasks according to the modified Bluetooth LE protocol and, in some cases, other tasks. The data packet or data set transmitted via the wireless communication link 12L is supplied to the wireless circuit 54 by the Bluetooth LE controller 56. The data packet received by the radio unit or radio circuit 54 via the RF antenna 53 is sent to the Bluetooth LE controller 56 for further data processing. Those skilled in the art will appreciate that the smartphone 50 typically includes a number of additional hardware and software resources in addition to those outlined. ..

FIG. 2 shows data sets having different priorities between, for example, the left ear hearing aid 10L and the smartphone 50 described above, for example, with the smartphone 50 configured as the master and the hearing aid 10L configured as the slave. FIG. 200 is a first timing diagram 200 showing a novel method of wireless communication.

FIG. 2 shows less coherent electromagnetic noise in the associated data channel, so transmission of each data packet or data set from the transmitter was successful in the first transmission attempt and therefore needs to be retransmitted. The operating state of the wireless communication link (12L in FIG. 1) is shown.

Consecutive connection events on the wireless communication link are indicated by Ci1, Ci2, Ci3, and the like along the time axis t. Those skilled in the art will appreciate that adjacent connection events shown, such as Ci1 and Ci2, can be separated according to the Bluetooth LE protocol with a fairly long sleep period, eg, up to 4 seconds. During such a sleep period, both the wireless circuit 34L of the left hearing aid 10L and the wireless circuit 54 of the smartphone 50 can be powered down to reduce power consumption. The connection event may have a duration or connection interval between 5 ms and 10 ms. The connection interval for each connection event is preferably one half of the selected audio frame size of the audio data set transmitted over the wireless communication link.

Table 2 below outlines the number of bytes required to hold audio data given a particular audio frame size in milliseconds. The listed values are for audio streams flowing at 48 kbit / s. For a 32 kbit / s audio stream, this is two-thirds of this requirement.

Two types of data with different priorities are transmitted over the wireless communication link, as shown in FIG. 2 with the symbols "A" and "D" of the data packets 205, 210, 215 or the data set. The data packet represented by A1 and A2 has the data of the first priority, and the data packet D has the second priority lower than the first priority. In the illustrated example, the first priority or higher priority data packet 205, 215 contains the audio data set and the lower priority data packet 210 is the Bluetooth core specification 4.1 or Includes various control data such as start, stop, codec negotiation, etc., based on the Bluetooth LE protocol of earlier versions. The data structures of the high priority data packets A1 and A2 are shown by the data packet 230. The high priority data packet 230 includes a header section 235 which can have 2 bytes. The high priority data packet 230 further includes the payload data 240 described above, which may include audio data between 60 and 120 bytes depending on the audio frame size. The 60-byte payload data size is approximately 1.5 ms long for each high priority data packet, which fits within the corresponding connection event time window. The header section 235 preferably comprises a so-called more data (MD: more data) field or bit represented by the symbol "1". This MD field indicates whether there is a low priority data packet D in the waiting state. The Bluetooth LE controller 56 of the transmitting device sets this MD bit when there is a low priority data packet D in the waiting state, and sets the MD bit to "If there is no low priority data D in the waiting state". Reset to "0". The Bluetooth LE controller 56 preferably sets the MD bit regardless of whether the transmitting device actually transmits the low priority data packet D within the same connection event Ci1 after the high priority data packet A1. Configured to set or reset. With this function, the receiving device skips or skips a connection event that does not have a low priority data packet D waiting between the connection events of a successful high priority data packet by examining the MD bit. It will be possible to eliminate it.

The low priority data packet D may have a length of 37 bytes. When the transmission sequence of the high priority data packet and the low priority data packet by the transmitting device is shown, the first high priority data packet A1 is transmitted first. After that, the operating mode of the radio circuit 54 of the transmitting device is inverted from the transmitting mode to the receiving mode during a short pause of, for example, about 150 μs. Therefore, the radio circuit 54 of the transmitter includes a Bluetooth transceiver. In the receive mode, the radio circuit 54 of the transmitter monitors the communication link to ensure that the receiver, that is, the high priority data packet A1 transmitted from the left ear hearing aid 10L in the current situation, has definitely been received correctly. Indicates whether there is an acknowledgment received signal. The receipt of this acknowledgment signal or packet is indicated by the packet or signal 207 labeled "Ack". Since the MD bit discussed earlier in the header 235 of the high priority data packet A1 is set to "1", the low priority data packet D is in the waiting state and is waiting for transmission. Therefore, the transmitting device transmits the low priority data packet D210 in the waiting state as shown, and after another short pause, the second acknowledgment signal or packet 209 is received as shown.

At this point, the Bluetooth LE controller 26L of the receiving device reliably receives both the high-priority data packet A1 and the low-priority data packet D. Therefore, the Bluetooth LE controller 26L can safely abandon or skip the subsequent connection event Ci2, which would otherwise be used to retransmit the high priority data packet A1, which is described in more detail below. .. Therefore, the wireless transmitter / receiver of the receiver is not turned on during the second connection event Ci2, which saves a considerable amount of power compared to receiving and transmitting data packets.

During the third connection event Ci3, a new high priority data packet A2 (215) is transmitted to the receiving device, which then returns the acknowledgment packet 211 labeled "Ack" to the transmitting device. By doing so, an acknowledgment is given to the reliable reception. In the header 235 of the second high priority data packet A2, the MD bit can be set to "0" to indicate that there is no low priority data packet D in the waiting state. At this point, the Bluetooth LE controller 26L of the receiving device has reliably received the high priority data packet A2, and by examining the MD bit of the header of the packet A2, the low priority data packet D in the waiting state It can be concluded that there is no. Therefore, the Bluetooth LE controller 26L results in abandoning or skipping subsequent connection event Ci4 (not shown).

FIG. 3 shows another exemplary timing diagram 300 showing a novel way of wirelessly communicating data sets with different priorities. FIG. 3 shows, for example, the wireless communication link 12L of FIG. 1 where transmission of individual data packets or data sets from a transmitter to a receiver sometimes fails due to some coherent electromagnetic noise within the associated data channel. Indicates the operating status.

As described above in connection with FIG. 2, the continuous connection event of the wireless communication link is indicated by Ci1, Ci2, Ci3, Ci4 and the like along the time axis t. Those skilled in the art will appreciate that adjacent connection events, such as Ci1 and Ci2, can be separated from each other according to the Bluetooth LE protocol, with a fairly long sleep or inactivity period, eg, up to 4 seconds.

In FIG. 3, the transmission sequence of the high priority data packets A1, A2, and the low priority data packet D by the transmitting device starts from the transmission of the first high priority audio data packet A1. The transmitting device then switches the operation to the receiving mode described above and monitors the communication link for a positive response of the receiving signal or package transmitted by the receiving device, i.e. the left ear hearing aid 10L. In the illustrated communication sequence, transmission of the high priority data packet A1 within the connection event Ci1 is successful, and the receiving device transmits an acknowledgment signal or packet Ac. There is no low priority data packet D in the waiting state and waiting to be transmitted, and therefore, in the header of the high priority data packet A1, the above MD bit is placed in the data packet A1 of FIG. It is set to "0" as indicated by "= 0".

Since the high priority data is received and there is no low priority data packet D waiting, the receiving device skips the next connection event Ci2, which reduces power consumption in the receiving device.

Within the third connection event Ci3, the high priority data packet A2 was transmitted for the first time with limited success. The receiving device receives the data packet, for example a CRC detects a transmission error, the receiving device sends an acknowledgment signal or the data packet "Nack", and in some cases within the same connection event Ci3. The MD bit described above is set to "1" to request the retransmission of the data packet. Therefore, the data packet A2 is retransmitted in the same connection event Ci3, but in this example, a transmission error is detected in the receiving device, and the result is the same as the previous time. Optionally, to save power, the receiving device does not transmit a second "Nack" signal or packet.

A first retransmission is then performed within the subsequent connection event Ci4, this time the receiving device succeeds in receiving the data packet A2, and thus the receiving device sends an acknowledgment signal or packet to the transmitting device. do. As shown by "MD = 0" in the data packet A2 of FIG. 3, there is no low priority data packet D in the waiting state.

If the transmitted data packet is lost, the receiver does not send any signal, such as a "Nack" signal, and if there is no signal from the receiver, the connection event preferably ends to save power. Thus, preferably, no retransmission is made within the same connection event in which the first transmission of the data packet was made.

FIG. 4 shows another exemplary timing diagram 400 showing a novel way of wirelessly communicating data sets with different priorities. In this case, the maximum number of high priority data packet retransmissions within the new connection event is set to 1. FIG. 4 shows that transmission of individual data packets or data sets from a transmitter to a receiver can sometimes fail due to some interfering electromagnetic noise within the associated data channel, eg. The operating state of the wireless communication link 12L of the above is shown.

Similar to FIG. 3, the continuous connection event of the wireless communication link is indicated by Ci1, Ci2, Ci3, Ci4 and the like along the time axis t. Those skilled in the art will appreciate that adjacent connection events, such as Ci1 and Ci2, can be separated from each other according to the Bluetooth LE protocol, with a fairly long sleep or inactivity period, eg, up to 4 seconds.

Within the first connection event Ci1, the high priority data packet A1 is transmitted for the first time with limited success. The receiving device receives the data packet, for example a CRC detects a transmission error, the receiving device sends a negative response signal or the data packet "Nack", and in some cases within the same connection event Ci1. The MD bit discussed above is set to "1" to request the retransmission of the data packet A1. Therefore, the data packet A1 is retransmitted in the same connection event Ci1, but in this example, a transmission error is detected in the receiving device, which also results in the same result as before. Optionally, to save power, the receiving device does not transmit a second "Nack" signal or packet.

After that, the first retransmission is performed in the subsequent connection event Ci2, but a transmission error is continuously detected in the receiving device, a negative response signal or a data packet "Nack" is transmitted, and in some cases, the data packet "Nack" is transmitted. The MD bit discussed above is set to "1" to request the retransmission of the data packet A1 within the same connection event Ci2. Therefore, the data packet A1 is retransmitted in the same connection event Ci2, but it also results in a transmission error being detected in the receiving device.

As a result, the data packet A1 is flushed due to a timeout, and the transmitting device acquires the next high priority data packet A2 and transmits it in the connection event Ci3. The transmission is successful and the receiving device acknowledges the reception of the data packet A2. In the transmitting device, there is no data packet with a lower priority waiting to be transmitted, so that the MD bit is set to "0" in the header of the second high priority data packet A2. Therefore, the receiving device skips the fourth connection event Ci4, which saves power.

In the illustrated example, the predetermined maximum number of retransmissions of high priority data packets within a new connection event is 1, but larger maximums, such as 2, 3, or 4, may be selected. .. Also, the transmitting device is configured to retransmit low priority data packets until an acknowledgment of reception is received from the receiving device, i.e., without limiting the number of retransmissions to the maximum number of times selected. May be good.

Limiting the number of retransmissions of a particular high-priority data packet to the maximum number of times selected facilitates maintaining the real-time characteristics of the data packet received by the receiving device. If the number of retransmissions of a particular high-priority data packet reaches a predetermined maximum without success, the transmitter either flushes the particular high-priority data packet or the particular high-priority data. • Overwrites the packet with, for example, a new high-priority data packet representing the current audio content, followed by transmission of the new high-priority data packet. The loss of the former high priority data packet can be concealed by the receiving device, for example, by an appropriate packet loss concealment algorithm executed by the hearing loss processor 24L of the left hearing aid.

If the transmitted data packet is lost, the receiver does not send any signal, such as a "Nack" signal, and if there is no signal from the receiver, the connection event preferably ends to save power. Thus, preferably, no retransmission occurs within the same connection event in which the data packet was originally sent.

In the timing diagram of FIG. 5, the transmission of the high priority data packet A1 is successful in the connection event Ci1, and the receiving device transmits an acknowledgment signal or the packet “Ack” to the transmitting device to ensure reliable reception. Respond affirmatively. In the header of the first high priority data packet A1, the MD bit is set to "1", indicating that a new low priority data packet D1 is waiting to be transmitted to the receiving device. .. The transmitting device then transmits the low priority data packet D1 during the same connection event Ci1. The transmission is successful and the receiving device acknowledges the reception. Since the receiving device succeeds in receiving both the high-priority data packet A1 and the low-priority data packet D1, the second connection event Ci2 is skipped, thereby saving the power of the receiving device.

In the connection event Ci3, the transmission of the second high-priority data packet A2 to the receiving device is successful, and the receiving device responds affirmatively to the reception. In the header of the second high priority data packet A2, the MD bit is set to "1", indicating that a new low priority data packet D2 is waiting to be transmitted to the receiving device. .. The transmitting device then transmits the low priority data packet D2 during the same connection event Ci3. The transmission of the second low priority data packet D2 is unsuccessful and the receiving device does not acknowledge the reception, as indicated by the dotted box "Nack". If the data packet D2 is lost, the receiving device sends nothing to the transmitting device, and if the receiving device receives the data packet D2 but a transmission error is detected, the receiving device sends a "Nack" signal. You may.

Since there are no high priority data sets or packets waiting to be transmitted to the receiving device, the transmitting device subsequently receives a second data packet D2 having a low priority during the fourth connection event Ci4. Retransmitted and this time it was successful.

In FIG. 6, the transmission of the high priority data packet A1 is successful in the connection event Ci1, and the receiving device transmits an acknowledgment signal or the packet “Ack” to the transmitting device, thereby making an acknowledgment for reliable reception. do. In the header of the first high priority data packet A1, the MD bit is set to "1", indicating that a new low priority data packet D1 is waiting to be transmitted to the receiving device. The transmitting device then transmits the low priority data packet D1 during the same connection event Ci1. The transmission of the low priority data packet D1 fails and the receiving device does not acknowledge the reception, as indicated by the dotted box "Nack". If the data packet D1 is lost, the receiving device sends nothing to the transmitting device, and if the receiving device receives the data packet D1, but a transmission error is detected, the receiving device sends a "Nack" signal. You may.

Since there are no high-priority data sets or packets waiting to be transmitted to the receiving device, the transmitting device subsequently re-releases the second data packet D1 with low priority during the second connection event Ci2. The transmission is performed, but the transmission fails in the connection event Ci2. Within the connection event Ci3, the transmission of the new high priority data packet A2 is unsuccessful and is retransmitted as described above. After the high priority data packet A2 is successfully retransmitted, the low priority data packet D1 is finally successfully transmitted to the receiving device in the connection event Ci4.

In FIG. 7, the priority of the data packet waiting for retransmission increases as a function of, for example, the number of failed retransmission attempts, and the priority of the data packet waiting for retransmission becomes high priority. Indicates that a higher priority can be obtained than the data packet it has.

In FIG. 7, the transmission of the high priority data packet A1 is successful in the connection event Ci1, and the receiving device transmits an acknowledgment signal or the packet “Ack” to the transmitting device, thereby making an acknowledgment for reliable reception. do. In the header of the first high priority data packet A1, the MD bit is set to "1", indicating that a new low priority data packet D1 is waiting to be transmitted to the receiving device. .. The transmitting device then transmits the low priority data packet D1 during the same connection event Ci1. The transmission of the low priority data packet D1 fails and the receiving device does not acknowledge the reception, as indicated by the dotted box "Nack". If the data packet D1 is lost, the receiving device sends nothing to the transmitting device, and if the receiving device receives the data packet D1, but a transmission error is detected, the receiving device sends a "Nack" signal. You may.

After the retransmission fails, the priority of the data packet D1 is set to the highest value, and the transmitting device subsequently sets the first data having the highest priority at this time during the second connection event Ci2. -The packet D1 is retransmitted, but the transmission fails in the connection event Ci2. In the connection event Ci3, the transmission of the data packet D1 fails again, but in the connection event Ci4, the transmission of the D1 to the receiving device finally succeeds. Further, within the same connection event Ci4, the transmission of the new high priority data packet A2 to the receiving device is successful.

FIG. 8 shows a flow chart of an example of the novel method.

The illustrated method 500 delivers audio, such as voice and / or music, from, for example, a hearing aid or headphones or another from a transmitter housed in a smartphone configured to be suitable for operation in accordance with the Bluetooth LE standard protocol. It can be used to stream to a receiving device housed in a hearing device.

According to the illustrated method 500, when streaming is required, according to the Bluetooth LE standard protocol, the audio data to be streamed is packed into audio data packets, also referred to as audio data sets throughout the disclosure. , Audio data packets are given high priority so that the transmission of audio data packets is not interrupted by the transmission of control data, such as commands to increase the volume of the auditory device. ..

The audio data packets are sent in sequence by the following steps.
510: A step of establishing a connection event in a series of consecutive connection events in accordance with the Bluetooth LE standard protocol.
520: From the transmitting device to the receiving device, a high priority is given to at least one audio data packet or audio data set in the series of audio data packets or audio data sets to be streamed. Steps to send to receive,
530: A step of waiting for an acknowledgment of reception from the receiving device.
540: If there is no acknowledgment of reception from the receiving device, 520: Retransmitting at least one audio data packet or audio data set.
550: If there is an acknowledgment of reception from the receiving device
560: Lower than the priority given to the audio data packet when the transmitter would have retransmitted at least one audio data packet or audio data set without an acknowledgment. A step of transmitting a second data packet or data set having a second priority from a transmitting device to a receiving device.

Preferably, the audio data packets of the streamed audio have a high priority, thereby ensuring high fidelity or at least acceptable quality of the sound produced based on the streamed audio. , Ensures that audio data packets are transmitted before transmitting other types of data sets with lower priority.

The method may further include assigning an L2CAP channel to the transmission of an audio data set, eg, one L2CAP channel to the control data associated with the audio data set and / or one. This is by assigning the L2CAP channel to the first audio data set and, in some cases, another L2CAP channel to the second audio data set.

The following three fixed L2CAP channels can be assigned to audio transmission.
1) Control data (start, stop, codec negotiation, etc.)
2) Left audio data 3) Right audio data

Only devices capable of receiving one audio stream (left or right), such as hearing aids, are used for channels 1) and 2), or channels 1) and 3). In a device with integrated stereo functions, such as a stereo headset, all three channels are used. The audio data set may be unidirectional or bidirectional, depending on the field of application, and the control data channel should allow negotiation in that regard.

FIG. 9 shows a flow chart of another example 500'of the novel method, which includes the following steps in addition to the steps of method 500 shown in FIG.
In step 520: In at least one data packet, whether or not a data set with a second priority is waiting to be transmitted to the receiver is encoded, for example, in data bytes or data bits. Steps to include the information.
570: A step of checking whether a data set having a second priority is waiting to be transmitted to a receiver,
580: Between a transmitter and a receiver to transmit a second data set with a second priority if there is no data set with a second priority waiting to be transmitted to the receiver. Steps to stop establishing a connection.
590: If the data set with the second priority is waiting to be transmitted to the receiver
560: Lower than the priority given to the audio data packet when the transmitter would have retransmitted at least one audio data packet or audio data set without an acknowledgment. A step of transmitting a second data packet or data set having a second priority from a transmitting device to a receiving device.

FIG. 10 shows a flow chart of another example 500 ″ of the novel method, comprising the following steps in addition to the steps of method 500 shown in FIG.
In step 510: A step of setting the counter for the number of attempts to retransmit the audio data packet transmitted in step 520 to zero.
In step 520: A step of incrementing the counter by 1.
540: If there is no acknowledgment of reception from the receiving device
600: Step to check the value of the counter for the number of attempts to retransmit the audio data packet.
610: If the value is less than 2, 520: Increment the counter by 1 and retransmit at least one audio data packet or audio data set.
620: If the value is equal to 2, 560: To an audio data packet when the transmitter would have retransmitted at least one audio data packet or audio data set without an acknowledgment. A step of transmitting a second data packet or data set having a second priority lower than the given priority from the transmitting device to the receiving device.

Further method steps 600, 610, and 620 may be added to the method 500'as shown in FIG. 11 showing a flow chart of another example 500 ″ of the new method.

The permissible number of attempts to retransmit other types of data may be different from 1 and may not be limited, i.e. different maximums, no maximums, or infinite maximums, but various others. May be assigned to data of type.

Different types of data may also have different predetermined maximum values for retransmission attempts, for example, an audio data set may have a maximum value of 2, while the audio data set has priority. The maximum value of a data set with a lower priority than the degree may have a higher maximum value.

Advantageously, the novel method illustrated is facilitated by the limited use of Bluetooth LE control and link layer extensions for the transmission of audio data packets or sets using Bluetooth LE. And, for example, actions related to security and link setup are performed as specified in the Bluetooth Core Specification.

Advantageously, the novel method illustrated is facilitated by the limited use of Bluetooth LE control and link layer extensions for the transmission of audio data packets or sets using Bluetooth LE. And, for example, actions related to security and link setup are performed as specified in the Bluetooth Core Specification.
List the features of the techniques described in the specification.
(Feature 1)
A method of wirelessly communicating data sets
A step of transmitting the first data set of the first data category from the transmitting device to the receiving device.
If there is no acknowledgment of reception from the receiver, the step of retransmitting the first data set and
If there is an acknowledgment of the reception from the receiver, then the transmitter and the receiver would have been connected for the retransmission in the absence of the acknowledgment, the first data category. A method comprising transmitting a second data set of a second data category different from the above from the transmitting device to the receiving device.
(Feature 2)
The method according to feature 1, wherein the first data set has a first priority and the second data set has a second priority lower than the first priority.
(Feature 3)
A step of transmitting a signal from the transmitting device to the receiving device as to whether or not the data set of the second data set is waiting for transmission to the receiving device, and a step of transmitting a signal from the transmitting device to the receiving device.
If there is no data set in the second data set waiting to be transmitted to the receiver, then the transmitter and receiver for transmitting the data set in the second data set. The method according to feature 1 or 2, comprising the step of stopping the establishment of said connection between.
(Feature 4)
The method of feature 2, wherein the information about whether the data set of the second data set is waiting to be transmitted to the receiver is encoded in a single data bit.
(Feature 5)
The method according to any one of features 1 to 4, comprising transmitting and receiving data conforming to the Bluetooth Low Energy standard.
(Feature 6)
The method of feature 4, comprising the step of assigning an L2CAP channel to the transmission of an audio data set.
(Feature 7)
The method of feature 5, comprising the step of assigning one L2CAP channel to control data associated with an audio data set.
(Feature 8)
The method of feature 5 or 6, comprising the step of assigning one L2CAP channel to a first audio data set.
(Feature 9)
The method of feature 7, comprising the step of assigning another L2CAP channel to a second audio data set.
(Feature 10)
The audio data set, provided that the number of attempts to retransmit the same audio data set is less than a predetermined maximum if there is no acknowledgment of reception from the receiver of the audio data set. 4. The method of any of features 4-8, comprising the step of retransmitting.
(Feature 11)
The method according to feature 9, wherein the maximum value is 2.
(Feature 12)
The method of feature 9 or 10, wherein different types of data have different predetermined maximum values for retransmission attempts.
(Feature 13)
Transmission delay difference between at least two different receivers connected to receive different audio data sets from said transmitter to at least one receiver configured to receive audio data sets. The method according to any of features 1-12, comprising the step of transmitting synchronous data, including timing information associated with.
(Feature 14)
12. The method of feature 12, comprising determining synchronization data based on ping transmissions from said transmitter to at least two different receivers.
(Feature 15)
13. The method of feature 13, comprising ping transmission using the L2CAP control channel.
(Feature 16)
An auditory device comprising a communication controller configured to be suitable for operation according to any of features 1 to 15.
(Feature 17)
The hearing device according to feature 15, wherein the hearing device is a hearing aid.

Claims (17)

A method of wirelessly communicating data sets
A step of transmitting the first data set of the first data category from the transmitting device to the receiving device.
If there is no acknowledgment of reception from the receiver, the step of retransmitting the first data set and
If there is an acknowledgment of the reception from the receiver, then the transmitter and the receiver would have been connected for the retransmission in the absence of the acknowledgment, the first data category. A method comprising transmitting a second data set of a second data category different from the above from the transmitting device to the receiving device. The method of claim 1, wherein the first data set has a first priority and the second data set has a second priority that is lower than the first priority. A step of transmitting a signal from the transmitting device to the receiving device as to whether or not the data set of the second data set is waiting for transmission to the receiving device, and a step of transmitting a signal from the transmitting device to the receiving device.
If there is no data set in the second data set waiting to be transmitted to the receiver, then the transmitter and receiver for transmitting the data set in the second data set. The method of claim 1 or 2, comprising the step of stopping the establishment of said connection between. The method of claim 2, wherein the information about whether the data set of the second data set is waiting to be transmitted to the receiver is encoded in a single data bit. The method according to any one of claims 1 to 4, comprising transmitting and receiving data conforming to the Bluetooth Low Energy standard. The method of claim 4, comprising the step of allocating an L2CAP channel for transmission of an audio data set. The method of claim 5, comprising assigning one L2CAP channel to control data associated with an audio data set. The method of claim 5 or 6, comprising the step of assigning one L2CAP channel to a first audio data set. The method of claim 7, comprising the step of assigning another L2CAP channel to a second audio data set. The audio data set, provided that the number of attempts to retransmit the same audio data set is less than a predetermined maximum if there is no acknowledgment of reception from the receiver of the audio data set. The method of any of claims 4-8, comprising the step of retransmitting. The method of claim 9, wherein the maximum value is 2. The method of claim 9 or 10, wherein different types of data have different predetermined maximum values for retransmission attempts. Transmission delay difference between at least two different receivers connected to receive different audio data sets from said transmitter to at least one receiver configured to receive audio data sets. The method of any one of claims 1-12, comprising the step of transmitting synchronous data, comprising timing information relating to. 12. The method of claim 12, comprising determining synchronization data based on ping transmissions from said transmitter to said at least two different receivers. 13. The method of claim 13, comprising pinging transmission using the L2CAP control channel. An auditory device comprising a communication controller configured to be suitable for the operation according to any one of claims 1 to 15. The hearing device according to claim 15, wherein the hearing device is a hearing aid.

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