Point-to-multipoint wireless audio bidirectional transmission method, system and device

Abstract

The present application relates to the field of wireless technology, and in particular to a method, system and device for wireless audio bidirectional transmission from single point to multipoint. The method for wireless audio bidirectional transmission from single point to multipoint includes the master and slave devices controlling the access timing of the slave device based on the isochronous communication time slot structure through random access window period and control time slot, and configuring link resources for the slave device, completing the broadcast transmission of the master device data packet in the point-to-multipoint audio broadcast time slot, and completing the independent transmission of the slave device data packet in the multipoint-to-point audio transmission time slot, realizing efficient management and allocation of link resources, thereby comprehensively solving the problems of low efficiency of single-point to multipoint wireless audio bidirectional transmission links in the prior art.

Description

Technical Field

[0001] The present application relates to the field of wireless technology, and in particular to a method, system and device for point-to-multipoint wireless audio bidirectional transmission. Background Art

[0002] At present, wireless audio technology brings people unfettered freedom to talk and enjoy music, and has won wide popularity. In particular, Bluetooth Low Energy (BLE) audio technology uses the synchronous isochronous channel (Isochronous Channels) protocol, that is, the connected isochronous stream (CIS: ConnectedIsochronous Stream) link of single-point to single-point communication and the connected isochronous group (CIG: ConnectedIsochronous Group) protocol composed of multiple CIS links to achieve single-point to single-point one-way or two-way audio transmission, and the broadcast isochronous stream (BIS: Broadcast Isochronous Stream) link of single-point to multi-point communication and the broadcast isochronous group (BIG: Broadcast Isochronous Group) protocol composed of multiple BIS links to achieve single-point to multi-point one-way audio transmission, thus bringing people lower power consumption, lower cost, higher quality, lower latency, and richer wireless audio services. For example, a wireless multi-microphone application uses a connected isochronous group (CIG) protocol composed of multiple connected isochronous stream (CIS) protocols for point-to-point communication.

[0003] However, for wireless multi-microphone applications or multi-player wireless gaming applications with point-to-multipoint bidirectional audio transmission, the CIS master device usually uses multiple bidirectional CIS links to send the same audio. Multiple CIS links must be established between the CIS master device and multiple CIS slave devices, and the bidirectional data of each CIS is sent independently, resulting in low link efficiency. In addition, the more CIS links the CIS master device establishes, the fewer time slots are used to search and access new devices, making it more difficult to access new devices. In order to maintain good access performance, sufficient search time slots must be reserved, which will further lead to low link efficiency.

[0004] Therefore, as the link is used, the efficiency of the wireless link will become lower and lower, and fewer CIS links can be established or fewer wireless microphones or wireless gaming headsets can be connected. Summary of the invention

[0005] The present application proposes a single-point to multi-point wireless audio bidirectional transmission method, system and device, and provides a hybrid isochronous stream link protocol to solve the problems of low efficiency of single-point to multi-point wireless audio bidirectional transmission links in the prior art.

[0006] In order to solve the above technical problems, this application is implemented as follows:

[0007] In a first aspect, an embodiment of the present application provides a point-to-multipoint wireless audio bidirectional transmission method, the method comprising:

[0008] The isochronous communication interval used for the wireless audio bidirectional transmission includes an advertising time slot, a control time slot, a point-to-multipoint audio broadcast time slot, and a multipoint-to-point audio transmission time slot;

[0009] In the point-to-multipoint audio broadcast time slot, the master device broadcasts and sends a master device data packet;

[0010] In the advertising time slot, the master device broadcasts and sends synchronization information for synchronization of the slave device;

[0011] After the random access event is triggered, the master device opens a random access window; during the opening of the random access window, the master device sends a random access command in the control time slot and receives a random access request sent by the slave device; after the random access window is closed, the master device determines the slave device that is allowed to access, and allocates an independent slave device data packet sending time slot for the slave device that is allowed to access in the multi-point-to-point audio transmission time slot; the master device configures an access permission command according to the random access request and the slave device data packet sending time slot, and sends the access permission command in the control time slot to instruct the slave device that is allowed to access to establish a wireless communication link with the master device;

[0012] The master device receives the slave device data packet in each allocated slave device data packet sending time slot based on the wireless communication link.

[0013] In a second aspect, an embodiment of the present application provides a point-to-multipoint wireless audio bidirectional transmission method, including:

[0014] The isochronous communication interval used for the wireless audio bidirectional transmission includes an advertising time slot, a control time slot, a point-to-multipoint audio broadcast time slot, and a multipoint-to-point audio transmission time slot;

[0015] The slave device searches for synchronization information sent by the master device in an advertising time slot of an isochronous communication interval, and synchronizes with the master device according to the synchronization information;

[0016] After synchronization with the master device, receiving a random access command sent by the master device in a control time slot of the isochronous communication interval; and sending a random access request to the master device in the control time slot during an open random access window of the master device according to the random access command; receiving an access permission command sent by the master device in the control time slot after the random access window is closed, and establishing a wireless communication link with the master device if the access permission command indicates that the slave device is allowed to access;

[0017] Based on the wireless communication link, wireless audio bidirectional transmission is performed with the master device, the master device data packet broadcasted by the master device is received in the point-to-multipoint audio broadcast time slot of the isochronous communication interval, and the slave device data packet is sent in the slave device data packet sending time slot allocated by the master device.

[0018] In a third aspect, an embodiment of the present application provides a point-to-multipoint wireless audio bidirectional transmission device, wherein the device is a master device and can implement the point-to-multipoint wireless audio bidirectional transmission method provided in the first aspect of the embodiment of the present application, including:

[0019] Radio frequency transceiver module, used for receiving and sending wireless signals;

[0020] A baseband data and protocol processor is used to control the radio frequency transceiver module to communicate with the slave device based on an isochronous communication interval, wherein:

[0021] In the point-to-multipoint audio broadcast time slot of the isochronous communication interval, broadcast and send a master device data packet;

[0022] Broadcasting and sending synchronization information for synchronization of slave devices in an advertising time slot of the isochronous communication interval;

[0023] After the random access event is triggered, a random access window is opened; during the period when the random access window is open, a random access command is sent in the control time slot of the isochronous communication interval, and a random access request sent by a slave device is received; after the random access window is closed, a slave device that is allowed to access is determined, and an independent slave device data packet sending time slot is allocated to the slave device that is allowed to access in the multi-point-to-point audio transmission time slot; an access permission command is configured according to the random access request and the slave device data packet sending time slot; and the access permission command is sent in the control time slot to instruct the slave device that is allowed to access to establish a wireless communication link with the master device;

[0024] Based on the wireless communication link, a slave device data packet is received in each allocated slave device data packet transmission time slot.

[0025] In a fourth aspect, an embodiment of the present application provides a point-to-multipoint wireless audio bidirectional transmission device, wherein the device is a slave device, and can implement the point-to-multipoint wireless audio bidirectional transmission method provided in the first aspect of the embodiment of the present application, including:

[0026] Radio frequency transceiver module, used for receiving and sending wireless signals;

[0027] A baseband data and protocol processor, used to control the radio frequency transceiver module to communicate with the master device, wherein: searching for synchronization information sent by the master device in the advertising time slot of the isochronous communication interval, and synchronizing with the master device according to the synchronization information;

[0028] After synchronization with the master device, receiving a random access command sent by the master device in a control time slot of the isochronous communication interval; sending a random access request to the master device in the control time slot during an open random access window of the master device according to the random access command;

[0029] After the random access window is closed, receiving an access permission command sent by the master device in the control time slot, and establishing a wireless communication link with the master device if the access permission command indicates that the slave device is allowed to access;

[0030] Based on the wireless communication link, wireless audio bidirectional transmission is performed with the master device, the master device data packet broadcasted by the master device is received in the point-to-multipoint audio broadcast time slot of the isochronous communication interval, and the slave device data packet is sent in the slave device data packet sending time slot allocated by the master device.

[0031] In a fifth aspect, an embodiment of the present application provides a point-to-multipoint wireless audio bidirectional transmission system, characterized in that it includes:

[0032] The main device provided by the third aspect of the embodiment of the present application;

[0033] At least 2 slave devices provided in the fourth aspect of the embodiment of the present application.

[0034] In a fifth aspect, an embodiment of the present application provides an electronic device, comprising: a processor, a memory, and a program stored in the memory and executable on the processor, wherein when the program is executed by the processor, the steps of the multi-point to single-point wireless audio transmission method as described in the first aspect or the second aspect are implemented.

[0035] In a sixth aspect, an embodiment of the present application provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the single-point to multi-point wireless audio bidirectional transmission method of the first aspect and the second aspect are implemented.

[0036] The beneficial effects brought by the technical solution provided by the embodiment of the present application include at least:

[0037] Through the above method, the master and slave devices control the access timing of the slave device based on the isochronous communication time slot structure through random access window period and control time slot, and configure link resources for the slave device, complete the broadcast transmission of the master device data packet in the point-to-multipoint audio broadcast time slot, and complete the independent transmission of the slave device data packet in the multi-point to point audio transmission time slot, thereby realizing efficient management and allocation of link resources, thereby comprehensively solving the problems of low efficiency of single-point to multi-point wireless audio two-way transmission links in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0039] Figure 1 A flow chart of a point-to-multipoint wireless audio bidirectional transmission method provided in an embodiment of the present application;

[0040] Figure 2 A schematic diagram of an isochronous communication interval of a point-to-multipoint wireless audio bidirectional transmission method provided in an embodiment of the present application;

[0041] Figure 3 A schematic diagram of a data packet header provided in an embodiment of the present application;

[0042] Figure 4 A flow chart of another single-point to multi-point wireless audio bidirectional transmission method provided in an embodiment of the present application;

[0043] Figure 5 A schematic diagram of the structure of a wireless point-to-multipoint bidirectional audio transmission system provided in an embodiment of the present application;

[0044] Figure 6 A schematic diagram of a payload structure of a HIGC PDU provided in an embodiment of the present application;

[0045] Figure 7 A schematic diagram of a control data structure of a random access command provided in an embodiment of the present application;

[0046] Figure 8 A schematic diagram of a control data structure of a random access request provided in an embodiment of the present application;

[0047] Fig. 9 A schematic diagram of a control data structure of a random access grant provided in an embodiment of the present application;

[0048] Fig.10 A schematic diagram of a control data structure of an access termination command provided in an embodiment of the present application;

[0049] Fig.11 A schematic diagram of a process of accessing a wireless communication link from a device provided in an embodiment of the present application;

[0050] Fig.12 A schematic diagram of a wireless communication link process of a master device provided in an embodiment of the present application;

[0051] Fig.13 A schematic diagram of the structure of a wireless audio transceiver device provided in an embodiment of the present application;

[0052] Fig.14 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0054] In the description of the embodiments of the present application, the term "including" and similar terms should be understood as open inclusion, that is, "including but not limited to". The term "based on" should be understood as "based at least in part on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0055] Regarding some basic terms and their English abbreviations in the art involved in the embodiments of the present application, some introductions are first made to facilitate the description of the embodiments:

[0056] CIS: Connected Isochronous Stream, connected isochronous stream;

[0057] CIG: Connected Isochronous Group, connected isochronous group;

[0058] BIS: Broadcast Isochronous Stream, broadcast isochronous stream;

[0059] BIG: Broadcast Isochronous Group, broadcast isochronous group;

[0060] HIS: Hybrid Isochronous Stream, hybrid isochronous flow;

[0061] HIG: Hybrid Isochronous Group, mixed isochronous group;

[0062] HISM: Hybrid Isochronous Stream Master, hybrid isochronous stream master;

[0063] HISS: Hybrid Isochronous Stream Slave, hybrid isochronous stream slave device;

[0064] HIGC:HIG Control, hybrid isochronous flow control;

[0065] Isochronous Interval: isochronous communication interval;

[0066] SE:Sub-Event, sub-event;

[0067] T_MSS: Time of Minimum Subevent Space, minimum event interval;

[0068] RFU: Reserved for future use, reserved unit;

[0069] SN: Sequence Number, master device data packet sequence number;

[0070] HIS Num: the maximum number of accessible slave devices or HIS links;

[0071] HIS MT: HIS Mapping Table, the slave device mapping table to which slave device data packets need to be sent;

[0072] BLE: Bluetooth Low Energy, Bluetooth low energy consumption;

[0073] PDU: Protocol Data Unit, protocol data unit;

[0074] BLE CIS Null PDU: Bluetooth low energy connection isochronous stream null protocol data unit;

[0075] BLE CIS PDU: Bluetooth low energy connection isochronous stream protocol data unit;

[0076] LC3: Low Complexity Communication Codec, low complexity communication codec;

[0077] SDU: Service Data Unit, service data unit;

[0078] SN: Sequence Number, sequence number;

[0079] NESN:Next Expected Sequence Number, the next expected sequence number.

[0080] LLID: Logical Link Identifier, used to indicate the load type of CIS Data PDU;

[0081] Length: Length, indicating the PDU payload length.

[0082] Please refer to Figure 1 , Figure 1 The flowchart of a method for bidirectional transmission of wireless audio from one point to multiple points provided by an embodiment of the present application is shown. The method can be applied to a master device in a wireless audio transmission system:

[0083] The isochronous communication interval (IsochronousInterval) of the point-to-multipoint wireless audio bidirectional transmission may include an advertising time slot, a control time slot, a point-to-multipoint audio broadcast time slot, and a multipoint-to-point audio transmission time slot;

[0084] In the point-to-multipoint audio broadcast time slot, the master device broadcasts and sends a master device data packet;

[0085] In the advertising time slot, the master device broadcasts and sends synchronization information for synchronization of the slave device;

[0086] The synchronization information may include the time slot structure information of the isochronous communication interval for the single-point to multi-point wireless audio bidirectional transmission. For example, it may include the indication information of the control time slot, so that after the slave device is synchronized with the master device based on the synchronization information, it can receive the control signal sent by the master device in the control time slot; it may also include the indication information of the point-to-multipoint audio broadcast time slot, so that after the slave device is synchronized with the master device, it can receive the master device data packet sent by the master device in the time slot, thereby realizing the single-point to multi-point wireless audio unidirectional transmission. In addition, the synchronization information may also include the starting time point of the isochronous communication interval, the duration of the isochronous communication interval, the frequency hopping sequence, the channel information, the clock synchronization signal and other information used for the synchronization of the slave device. Therefore, once the slave device searches for the synchronization information, it can synchronize with the master device.

[0087] For example, Figure 2 A time slot structure of an isochronous communication interval in an embodiment of the present application is shown. Using this time slot structure, and the single-point to multi-point wireless audio bidirectional transmission method provided in the embodiment of the present application, a hybrid isochronous stream HIS link protocol and a hybrid isochronous group HIG protocol composed of at least two HIS links can be implemented. The master device performs wireless audio bidirectional transmission with at least two slave devices through a hybrid isochronous group HIG composed of at least two HIS links. For ease of description, the specific application of the HIS protocol and the HIG protocol implemented in the embodiment of the present application will be described in detail below. It can be understood that the single-point to multi-point wireless audio bidirectional transmission method provided in the embodiment of the present application can also be applied to other wireless communication scenarios, or to implement other wireless communication protocols.

[0088] Figure 2 The isochronous communication interval shown includes advertising slots (such as Figure 2 The time slot marked ADV in Figure 2 The two-way audio transmission time slot may include at least one data cycle, each of which includes a point-to-multipoint audio broadcast time slot (such as Figure 2 The time slots for HISM) and multi-point to point audio transmission time slots (such as Figure 2 The time slot of HISS is marked in ).

[0089] Step 11: After the random access event is triggered, the master device opens a random access window.

[0090] Exemplarily, the triggering of the random access event may be automatically triggered according to a preset condition, or may be manually triggered, etc. After the random access event is triggered, the master device opens a random access window to receive an access request from a slave device, such as a request signal packet sent by the slave device.

[0091] Step 12: During the period when the random access window is open, the master device sends a random access command in the control time slot and receives a random access request sent by the slave device.

[0092] Typically, the control time slot can be used to transmit control information between the master device and the slave device, such as the random access command and random access request in this implementation, and some other control instructions, such as sound effect control and transmission power control.

[0093] The control time slot may include one or more master device transmission time slots (or slave device reception time slots) and slave device transmission time slots (or master device reception time slots). The master device sends control information to the slave device in the master device transmission time slot and receives control information sent by the slave device in the slave device transmission time slot.

[0094] In some specific embodiments, in order to save link resources, the control time slot includes a master device sending time slot and a slave device sending time slot.

[0095] refer to Figure 2 The schematic diagram of the time slot structure shown in FIG. 1 shows that the master device sends the time slot when the master device controls the time slot ( Figure 2 The random access command is sent in the time slot ( Figure 2 The time slot marked with SHIGC in the time slot) receives the random access request sent by the slave device.

[0096] Step 13: After the random access window is closed, the master device determines the slave devices that are allowed to access, and allocates independent slave device data packet transmission time slots for the slave devices that are allowed to access in the multi-point-to-point audio transmission time slots.

[0097] Specifically, after the random access window is open, the master device determines the slave device that is allowed to access according to the received random access request, and allocates a slave device data packet sending time slot of the slave device in the equal time interval to the slave device that is allowed to access according to the information of the slave device that is allowed to access. Figure 2 For example, slave device S1 is allocated to HISS 1 time slot as its slave device data packet sending time slot, and slave device S2 is allocated to HISS 2 time slot as its slave device data packet sending time slot.

[0098] Step 14, the master device configures an access permission command according to the random access request and the slave device data packet transmission time slot, and sends the access permission command in the control time slot to instruct the slave device that is allowed to access to establish a wireless communication link with the master device.

[0099] Specifically, the master device sends the access permission command in the control time slot, for example, referring to Figure 2 The master device sends an access permission command in the M-HIGC time slot, and the access permission command includes the necessary information required for the slave device allowed to access to establish a wireless communication link with the master device, such as the slave data packet sending time slot of the slave device allowed to access in the isochronous communication interval, the address information of the slave device allowed to access, etc.

[0100] Step 15: The master device receives a slave device data packet in each allocated slave device data packet sending time slot based on the wireless communication link.

[0101] Specifically, the master device can perform the single-point to multi-point wireless audio bidirectional transmission with the slave device based on the wireless communication link, and each allocated slave device data packet sending time slot is the master device's data packet receiving time slot.

[0102] According to the single-point to multi-point wireless audio bidirectional transmission method described in steps 11-14, the master device controls the random access timing of the slave device by controlling the opening and closing of the random access window, without the need for the master device to access the slave device by continuous scanning in the prior art, which can reduce power consumption. At the same time, based on the isochronous communication time slot structure, the master device realizes random access of the slave device while occupying very few link resources, and realizes the transmission of audio data and control commands in a point-to-multipoint broadcast mode, thereby effectively managing and allocating link resources and significantly improving link efficiency.

[0103] Optionally, in some embodiments, allocating an independent slave device data packet transmission time slot to the slave device allowed to access in the multi-point-to-point audio transmission time slot includes:

[0104] In the multi-point-to-point audio transmission time slot, allocating a slave device data packet transmission time slot to the slave device that is allowed to access, so that the slave device data packet transmission time slots of each slave device that is allowed to access do not overlap with each other;

[0105] The master device configures the access permission command, including: configuring the access permission command to carry the slave device data packet sending time slot indication information.

[0106] Specifically, the slave device data packet transmission time slots allocated to the slave devices allowed to access may be allocated each time according to the duration occupied by the slave device data packets PDUs of different slave devices, or may be allocated according to a preset default slave device data packet transmission duration.

[0107] Optionally, in some embodiments, allocating an independent slave device data packet transmission time slot for the slave device allowed to access in the multi-point-to-point audio transmission time slot includes: acquiring a maximum duration occupied by a slave device data packet from a random access request sent by the slave device allowed to access, and allocating a slave device data packet transmission time slot for the slave device allowed to access according to the maximum duration occupied by the slave device data packet;

[0108] The slave device data packet sending time slot indication information is the sending start time point of the slave device data packet.

[0109] Specifically, the master device can allocate a sending time slot for a slave device data packet to each slave device allowed to access based on parameters such as the total duration of multi-point to point audio transmission time slots, the total duration of data packet sending time slots occupied by the connected slave devices and / or the maximum duration occupied by the slave device data packet of each connected slave device.

[0110] Exemplary, reference Figure 2, the slave device data packet sending time slot of the slave device S1 is HISS 1, the slave device data packet sending time slot of the slave device S2 is HISS 2, and the slave device data packet sending time slot of the slave device SN is HISS N. HISS 1, HISS2 and HISS N do not overlap with each other.

[0111] Optionally, in some embodiments, the master device determines the slave devices that are allowed to access, further comprising allocating a wireless communication link to the slave devices that are allowed to access;

[0112] The master device configuring the access permission command further includes: configuring the access permission command according to the wireless communication link allocation information of the slave device that is allowed to access, so that the access permission command carries the wireless communication link allocation information of the slave device that is allowed to access;

[0113] The wireless communication link information includes: one or more of the serial number of the wireless communication link allocated to the slave device that is allowed to access, the access address, and the effective time of the access permission. Specifically, the wireless communication link information is necessary information that can indicate the slave device that is allowed to access to access the wireless communication link.

[0114] Optionally, in some embodiments, the random access request includes a device address of the slave device;

[0115] The master device configures the access permission command, further comprising: the master device obtains the device address of the slave device that is allowed to access, and sets the device address as the address of the slave device that is allowed to access in the access permission command.

[0116] Specifically, when the slave device receives the access permission command, it can compare the slave device address to see whether it is its own slave device address. If so, it indicates that the slave device is a slave device that is allowed to access.

[0117] Optionally, in some embodiments, the point-to-multipoint wireless audio bidirectional transmission method further includes:

[0118] In the control time slot, the master device sends a random access termination command to disconnect the wireless communication link with the designated slave device, or,

[0119] In the control time slot, when the master device receives the random access termination command sent by the slave device, it disconnects the wireless communication link with the slave device.

[0120] Specifically, in addition to sending access permission commands, the master device can also send termination commands within the control time slot. When there are too many slave devices connected, the master device can automatically or manually disconnect some slave devices to facilitate the access of new devices or to save link resources.

[0121] Optionally, in some embodiments, the control time slot includes a master device sending time slot and a slave device sending time slot; the master device sends the random access command, access permission command or random access termination command in the master device sending time slot, and receives the random access request or random access termination command sent by the slave device in the slave device sending time slot;

[0122] The synchronization information includes one or more of the time slot structure information of the isochronous communication interval, the starting time point of the isochronous communication interval, the duration of the isochronous communication interval, the frequency hopping sequence, the channel information, and the clock synchronization signal;

[0123] In the advertising time slot, the master device broadcasts the synchronization information via a Bluetooth low energy advertising packet;

[0124] The master device generates a master device control packet based on a Bluetooth low energy control protocol data unit, and transmits the random access command, the access permission command and / or the random access termination command through the master device control packet;

[0125] The master device data packet is a Bluetooth low energy broadcast isochronous stream BIS protocol data unit PDU with an extended header, and its payload is used to load the audio data sent by the master device to the slave device, and its header includes:

[0126] An indication bit for indicating whether it is a Bluetooth low energy broadcast isochronous stream protocol data unit of the extended packet header;

[0127] A first extension bit for indicating a master device data packet sequence number;

[0128] A second extension bit for indicating the maximum number of accessible slave devices;

[0129] The third extension bit of the slave device mapping table is used to indicate that a slave device data packet needs to be sent.

[0130] Specifically, the single-point to multi-point wireless audio bidirectional transmission method provided in the embodiment of the present application can be backward compatible with Bluetooth devices equipped with the existing BLE protocol.

[0131] Exemplary, reference Figure 3 A data packet header is shown, which is applied to Figure 2 The HIS / HIG protocol shown is used as an example to illustrate the composition of the master device data packet provided in the embodiment of the present application:

[0132] The data packet is an extended packet header based on the Bluetooth low energy broadcast isochronous stream protocol data unit, and can be applied to the data packet HISM PDU sent by the master device in the embodiment of the present application.

[0133] Based on the BIS PDU header, the data packet header uses the 1-bit reserved field (RFU: Reserved for Future Use) of the BIS PDU header to indicate whether the HIG link is enabled, that is, HIGE (Hybrid Isochronous Group Enable). When HIGE is assigned a value of 0, it means that the HIG function is not enabled. When HIGE is assigned a value of 1, it indicates that the HIG function is enabled; that is, when HIGE is assigned a value of 1, it indicates that the current data packet is a Bluetooth low energy broadcast isochronous stream protocol data unit with an extended header, which is the master device data packet HISM PDU of this embodiment. When HIGE is assigned a value of 0, it indicates that the current data packet is a Bluetooth low energy broadcast isochronous stream protocol data unit BIS PDU.

[0134] When the HIG function is enabled, the extended packet header increases a certain number of bytes, including three fields (extension bits): HIG SN, HIS Num and HIS MT.

[0135] refer to Figure 3 , the first extension bit is HIG SN, which is used to indicate the HISM PDU master device data packet sequence number (SN: Sequence Number); the second extension bit is HIS Num, which is used to indicate the maximum number of accessible slave devices or HIS link numbers; the third extension bit is HIS MT, which is used to indicate the slave device mapping table (MT: Mapping Table) to which the slave device data packet needs to be sent. Exemplarily, the bits of HIS MT correspond to the HIS link number or the slave device number from low to high. When a HIS slave device with a certain number is required to send a slave device data packet (such as HISS PDU), the bit corresponding to its number is set to 1, otherwise, it is set to 0.

[0136] Figure 3 As shown, the functions and usage of other fields of the data packet extension header are the same as those of the BIS PDU, including a logical link identifier (LLID: Logical Link Identifier) ​​for indicating the load type, a control subevent sequence number (CSSN: Control Subevent Sequence Number), a control subevent sending flag (CSTF: Control Subevent Transmission Flag), the length of the load (Length), and a 1-bit RFU.

[0137] Optionally, in some embodiments, the wireless communication link is a hybrid isochronous stream communication link.

[0138] The master device performs wireless audio bidirectional transmission with multiple slave devices that are allowed to access through a hybrid isochronous group consisting of multiple hybrid isochronous stream communication links, specifically including:

[0139] In the point-to-multipoint audio broadcast time slot of each data cycle, the master device data packet is broadcast and sent;

[0140] In each multi-point to point audio transmission time slot of each data cycle, receiving slave device data packets in each slave device data packet transmission time slot in turn;

[0141] Until the number of retransmissions of the master device data packet reaches the maximum number of retransmissions, or the slave device data packets sent by all slave devices that are allowed to access are correctly received by the master device, or the master device data packet is correctly received by all slave devices that are allowed to access, stop rebroadcasting the master device data packet and end this round of data communication;

[0142] Among them, one round of data communication is carried out at an isochronous communication interval, one round of data communication includes at least one data cycle, one data cycle includes a point-to-multipoint audio broadcast time slot and one or more slave device data packet sending time slots, and one slave device data packet sending time slot is allocated to a slave device that is allowed to access.

[0143] For example, Figure 2 As shown, in the point-to-multipoint audio broadcast time slot (HISM time slot) of each data cycle, the master device broadcasts the master device data packet to all slave devices; in the multi-point-to-point audio transmission time slot (HISS time slot HISS 1-HISS N time slot) of each data cycle (each SE interval in the figure corresponds to a data cycle), the slave device data packets are received in turn.

[0144] Exemplary, reference Figure 2 A round of data communication is carried out at an equal time interval. A round of data communication includes K+1 data cycles, K≥0. Each data cycle includes a point-to-multipoint audio broadcast time slot (HISM time slot). Each data cycle also includes a multi-point-to-point audio transmission time slot, which corresponds to the slave device data packet sending time slot of several slave devices.

[0145] In each round of data communication, if the number of retransmissions of the master device data packet reaches the maximum number of retransmissions, such as the preset maximum number of retransmissions of the master device data packet is 3 times, then regardless of whether the slave device receives it correctly, only 4 data cycles of data transmission are performed at most, and the master device stops retransmitting the master device data packet to the slave device, ending this round of data communication;

[0146] Alternatively, in each round of data communication, if all slave device data packets sent by the slave devices are correctly received by the master device, in this case, regardless of the preset maximum number of retransmissions, if the master device correctly receives all slave device data packets sent by the slave devices in one data cycle, the master device stops resending the master device data packets to the slave devices, and ends this round of data communication;

[0147] Alternatively, in each round of data communication, if the master device data packet is correctly received by all slave devices, in this case, no matter how many times the preset maximum number of retransmissions is, if all slave devices correctly receive the master device data packet sent by the master device in one data cycle, the master device stops resending the master device data packet to the slave devices and ends this round of data communication.

[0148] refer to Figure 4 The embodiment of the present application provides a point-to-multipoint wireless audio bidirectional transmission method, which can be applied to a slave device in a wireless audio transmission system, and is used for isochronous communication intervals of the wireless audio bidirectional transmission, including an advertising time slot, a control time slot, a point-to-multipoint audio broadcast time slot, and a multipoint-to-point audio transmission time slot; including:

[0149] Step 41, the slave device searches for synchronization information sent by the master device in the advertising time slot of the isochronous communication interval, and synchronizes with the master device according to the synchronization information.

[0150] Step 42: After synchronization with the master device, receive a random access command sent by the master device in a control time slot of the isochronous communication interval.

[0151] Step 43: According to the random access command, during the period when the random access window of the master device is open, send a random access request to the master device in the control time slot.

[0152] Specifically, after receiving the random access command, the slave device considers that the master device can receive access requests from each slave device, and can send a random access request to the master device. On the contrary, when the random access command is not received, the slave device does not send a random access request, or even if a random access request is sent, the master device does not process it. Step 44, after the random access window is closed, receives the access permission command sent by the master device in the control time slot, and if the access permission command indicates that the slave device is allowed to access, establishes a wireless communication link with the master device. Specifically, the slave device continuously receives the control information sent by the master device in the control time slot, and when receiving the access permission command sent by the master device, determines whether the master device allows the slave device to access according to the access permission command.

[0153] Step 45, performing wireless audio bidirectional transmission with the master device based on the wireless communication link, wherein the master device data packet broadcasted by the master device is received in the point-to-multipoint audio broadcast time slot of the isochronous communication interval, and the slave device data packet is sent in the slave device data packet sending time slot allocated by the master device.

[0154] Optionally, in some embodiments, the random access command or synchronization information may include the random access window open period information of the master device, so that the slave device can understand the open and closed status of the random access window. In other embodiments, once the slave device receives the random access command, it can be considered that the master device has opened the random access window, and once the random access command is not received for several consecutive times, it can be considered that the master device has closed the random access window.

[0155] Specifically, in some embodiments, the random access command carries time information for indicating a random access window open period of the master device; or the synchronization information carries time information for indicating a random access window open period of the master device;

[0156] The slave device determines the random access window opening period of the master device according to the random access command or synchronization information.

[0157] Exemplarily, the time information for indicating the random access window opening period of the master device may include a specific time period, a deadline and / or a start time of the random access window opening.

[0158] Optionally, in some embodiments, sending a random access request to the master device in the control time slot during an opening period of a random access window of the master device according to the random access command includes:

[0159] After receiving the random access command sent by the master device for the first time, during the period when the random access window of the master device is open, receiving the random access command sent by the master device during the period when the random access window is open after delaying at least once based on the random delay time;

[0160] During the period when the random access window of the master device is open, when a random access command sent by the master device is received after a delay based on the random delay time, a random access request is sent to the master device in the control time slot.

[0161] Specifically, random delay can avoid the situation where multiple slave devices simultaneously receive the random access command and send random access requests at the same time while controlling the time slot to occupy as few link resources as possible, resulting in access conflicts; random delay can well avoid this problem. The random delay time can be generated based on various random number methods in the prior art, and the number of random delays can also be determined according to the specific application scenario, which is not specifically limited in this application.

[0162] Exemplarily, if slave device S1 and slave device S2 receive a random access command at the same time, and slave device S1 receives the random access command again after a random delay of one equal time interval, it may send a random access request to the master device in the control time slot of the equal time interval; if slave device S2 receives the random access command again after a random delay of three equal time intervals, it may send a random access request to the master device in the control time slot of the equal time interval; since the delay time of the slave devices is randomly generated, it is possible to avoid slave device S1 and slave device S2 sending random access requests to the master device at the same time, thereby avoiding signal transmission and reception conflicts when there are many devices.

[0163] Optionally, in some embodiments, the control time slot includes a master device sending time slot and a slave device sending time slot; the slave device receives control information sent by the master device in the master device sending time slot, such as a random access command, and sends control information to the master device in the slave device sending time slot, such as a random access request.

[0164] The sending a random access request to the master device within the control time slot includes:

[0165] When receiving a random access command sent by the master device after a delay based on the random delay time, a slave device sends a random access request to the master device in a sending time slot within the control time slot.

[0166] Optionally, in some embodiments, the slave device may receive a random access command once after each random delay, and send a random access request once when receiving the random access command. Of course, in other embodiments, the slave device may not send a random access request every time it receives a random access command, such as sending a random access request only when receiving a random access request an odd number of times.

[0167] Exemplarily, a predetermined time interval, such as 150us, may be provided between two adjacent master device transmission time slots and slave device transmission time slots. After receiving a random access command in a master device transmission time slot, the slave device may delay for a predetermined time and then transmit a random access request in a slave device transmission time slot.

[0168] When the number of slave device transmission time slots included in the control time slot is limited, the embodiment of the present application uses random delay to stagger the timing of each slave device sending a random access command in the same slave device transmission time slot, which can save link resources and avoid access failure caused by signal conflict.

[0169] Optionally, in some embodiments, sending a random access request to the master device within the control time slot includes: configuring the random access request to carry a device address of the slave device and / or a maximum duration occupied by a slave device data packet;

[0170] After the random access window is closed, receiving an access permission command sent by the master device in the control time slot, and if the access permission command indicates that the slave device is allowed to access, establishing a wireless communication link with the master device, including:

[0171] Obtaining the address of the slave device that is allowed to access from the access permission command,

[0172] If the address of the slave device allowed to access is the same as the device address of the slave device, the wireless communication link is established with the master device.

[0173] For example, if slave devices S1, S2, and S3 respectively receive access permission commands, and the slave device address carried in the access permission command is the address of slave device S2, then after each slave device compares the address, only slave device S2 can confirm that it is the slave device allowed to access as specified in the access permission command. At this time, slave device S2 can establish the wireless communication link with the master device.

[0174] Optionally, in some embodiments, establishing a wireless communication link with the master device includes: obtaining, from the access permission command, wireless communication link information allocated by the master device to the slave device allowed to access, and establishing a wireless communication link with the master device based on the wireless communication link information.

[0175] Specifically, the access permission command carries, in addition to the slave device address, the wireless communication link serial number assigned to the slave device allowed to access, such as the slave device S2, which is assigned to the wireless communication link with serial number 2.

[0176] Optionally, in some embodiments, the slave device generates a slave device control packet based on a Bluetooth low energy control protocol data unit, and transmits the control information, such as the aforementioned random access request, random access termination command, etc., through the slave device control packet;

[0177] The slave device generates a slave device data packet based on a Bluetooth low energy connection isochronous stream protocol data unit, and transmits audio data through the slave device data packet.

[0178] Specifically, the slave device using the single-point to multi-point wireless audio bidirectional transmission method provided in the embodiment of the present application can be compatible with the ordinary BLE Bluetooth communication protocol, can generate a slave device control packet based on the Bluetooth low energy control protocol data unit, send a random access request or a random access termination command to the master device, etc., and can also generate a slave device data packet based on the Bluetooth low energy connection isochronous stream protocol data unit;

[0179] In addition, of course, the hybrid isochronous stream HIS link protocol provided in the embodiment of the present application and the hybrid isochronous group HIG protocol composed of at least two HIS links are also supported.

[0180] Optionally, in some embodiments, the wireless communication link is a hybrid isochronous stream (HIS) communication link; and the performing wireless audio bidirectional transmission with the host device based on the wireless communication link includes:

[0181] According to the information in the master device data packet, it is determined whether to send the slave device data packet to the master device in the slave device data packet sending time slot allocated by the master device, or to resend the slave device data packet.

[0182] For example, after receiving a master device data packet, the slave device can determine whether it needs to send a slave device data packet based on the information in the master device data packet. For example, if the information provided in the master device data packet is sent from devices S1 and S3, then slave devices S1 and S3 need to send their own slave device data packets, and other slave devices not involved do not need to send any.

[0183] Figure 5 The wireless single-point to multi-point bidirectional audio transmission system described in the present application is shown, and the audio transmission system is composed of at least two slave devices and one master device. Figure 5 Slave devices S1-SK, K slave devices, and a master device M are shown.

[0184] The following will describe in detail the HIS link protocol formed and the hybrid isochronous group HIG protocol composed of K HIS links in combination with the single-point to multi-point wireless audio bidirectional transmission method disclosed in this application. Figure 5 The specific application process of the audio transmission system.

[0185] Compared with the prior art that uses multiple bidirectional CIS links, the CIS master device must establish a CIS link with each CIS slave device, and the bidirectional data of each CIS is sent independently. Therefore, even if the data sent by the CIS master device to each CIS slave device is the same, it must be sent to each CIS slave device through each CIS link, so the link efficiency is low. However, by using the single-point to multi-point hybrid isochronous flow protocol disclosed in this application, such as the HIS protocol, the HIG master device uses the same protocol data unit (PDU: Protocol Data Unit) to send audio data to all HIG slave devices at the same time, that is, not separately, thereby improving the link efficiency.

[0186] The HIS and HIG protocols are based on the Bluetooth core specification BLE synchronous isochronous channels (Isochronous Channels) protocol, and use the single-point to multi-point wireless audio bidirectional transmission method published in this application to realize slave device access and master-slave device bidirectional communication. Among them, the master device uses the hybrid isochronous stream master (HISM: HybridIsochronousStreamMaster) protocol data unit (PDU: Protocol Data Unit) published in this application to send audio data, and the slave device uses the hybrid isochronous stream slave (HISS: HybridIsochronousStreamSlave) PDU to send audio data. HISM PDU has the same structure as BLE broadcast isochronous stream (BIS: Broadcast Isochronous Stream) PDU but different header format, that is, BIS PDU with extended header (Extended Header). HISS PDU has the same format as BLE connected isochronous stream (CIS: ConnectedIsochronousStream) PDU.

[0187] The format of the HISM PDU extension header is as follows Figure 3 As shown, the data packet header uses a 1-bit reserved field (RFU: Reserved for Future Use) based on the BIS PDU header to indicate whether the HIG link is enabled, that is, HIGE (Hybrid Isochronous Group Enable). When HIGE is assigned a value of 0, it means that the HIG function is not enabled, and when HIGE is assigned a value of 1, it means that the HIG function is enabled; that is, it is used to indicate whether it is the indicator bit of the Bluetooth low energy broadcast isochronous stream protocol data unit of the extended header.

[0188] When the HIG function is enabled, the extended packet header increases a certain number of bytes, including three fields (extension bits): HIG SN, HIS Num and HIS MT.

[0189] refer to Figure 3 , the first extended bit is HIG SN, which is used to indicate the HISM PDU master device data packet sequence number (SN: Sequence Number); the second extended bit is HIS Num, which is used to indicate the maximum number of accessible slave devices or HIS link numbers; the third extended bit is HIS MT, which is used to indicate the need to send a slave device mapping table (MT: Mapping Table mapping table) that indicates the need to send a slave device data packet. Exemplarily, the bits of HIS MT correspond to the HIS link number or the slave device number from low to high. When a HIS slave device with a certain number is required to send a slave device data packet (such as HISS PDU), the bit corresponding to its number is set to 1, otherwise, it is set to 0.

[0190] Figure 3 The functions and usage of other fields of the data packet extension header shown are the same as those of the BIS PDU, including the logical link identifier (LLID: Logical Link Identifier) ​​used to indicate the load type, the control subevent sequence number (CSSN: Control Subevent Sequence Number), the control subevent transmission flag (CSTF: Control Subevent Transmission Flag), the length of the load (Length), and 1-bit RFU.

[0191] According to the BLE BIG protocol, the HIG slave device obtains the HIG synchronization information through the BLE advertising packet sent by the HIG master device. After synchronization, it can receive the HISM PDU and HIG control (HIGC: HIG Control) PDU sent by the HIG master device. After the HIG slave device is synchronized with the HIG master device, it establishes a HIS link with the HIG master device through the HIGC PDU. After the HIS link is established, the HIG slave device can send HISS PDU to the HIG master device.

[0192] The structure of HIGC PDU is the same as that of BIG control PDU, that is, the two bits of LLID in the BLE BIG PDU header are set to 1 to obtain HIGC PDU. The payload structure of HIGC PDU is as follows: Figure 6 As shown, it includes two parts: operation code (Opcode) and control data (CtrData). The payload content of different HIGC commands, namely Opcode and CtrData, is different.

[0193] In some embodiments, four HIGC PDU types are defined, including:

[0194] HIS Random Access command (HIS Random Access)——Random access command;

[0195] HIS Access Request – random access request;

[0196] HIS Access Permit – access permission command;

[0197] HIS Terminate - access termination command.

[0198] Among them, the HIS random access command is used by the HIG master device to open a random access window to facilitate the HIG slave device to send a HIS access request, i.e., a random access request command to request access. Only within the random access window opened by the HIG master device, the HIG slave device is allowed to send the HIS Access Request command, and the HIG slave device cannot send the HIS Access Request command at other times.

[0199] HIS Access Request is used by the HIG slave device to request access or request to establish a HIS link when the HIG master device opens a random access window.

[0200] The HIS access permission, ie, the access permission command, is used by the HIG master device to permit the HIG slave device to access or establish a HIS link.

[0201] The HIS termination command is used by the HIG master device to terminate a certain HIS link or all HIS links, and can also be used by the HIG slave device to request the termination of the corresponding HIS link.

[0202] In some embodiments, the operation code of HIS Random Access is Opcode=0xD0, the operation code of HIS AccessRequest is Opcode=0xD1, the operation code of HIS Access Permit is Opcode=0xD2, and the operation code of HIS Terminate is Opcode=0xD3.

[0203] like Figure 7The control data of HIS Random Access is shown, including a 2-byte random access deadline, i.e., the lower 16 bits of the HIG event counter. When the current HIG link event counter is lower than the count threshold indicated by the deadline, the HIG slave device is allowed to send a random access request. After the HIG slave device receives the random access command, in order to avoid conflicts with random access requests sent by other slave devices, after a random delay of a certain time, the slave device receives the random access request command again and replies to the random access request. The random delay time does not exceed the deadline.

[0204] like Figure 8 The control data of the random access request is shown, including a 6-byte device address (Device Address), that is, the device address of the slave device requesting access, and a 2-byte maximum duration (Duration) occupied by the HISS PDU requesting access, in microseconds.

[0205] like Fig. 9 The control data of random access permission is shown, including a 1-byte HIS sequence number (HISSeq) for permission to access, a 6-byte device address (Device Address) of the slave device permitted to access, a 4-byte access address (Access Address) assigned to the slave device permitted to access, a 2-byte delay relative to the HISM PDU, i.e., the start time (Start Time) of the HISS PDU, in microseconds; and a 2-byte effective time (Instant), i.e., the lower 16 bits of the HIG event counter (HIGEvent Counter).

[0206] The slave device sends its device address to the master device through a random access request HIS Access Request.

[0207] The master device receives the address of the slave device during random access and saves it in the device address list. After the random access window is closed, the master device selects a specific slave device from the random access device address list and allows it to access and establish a HIS link by sending a random access permission HIS Access Permit command to the slave device with the corresponding device address. At the same time, the wireless communication link sequence number and access address are assigned to the slave device that is allowed to access through the HIS Access Permit command, and the start time is configured according to the maximum duration of the slave device data packet.

[0208] The slave device uses the assigned wireless communication link serial number and access address, and according to the configured start time, sends the slave device data packet HIS SPDU to the HIG master device on the corresponding time slot of the HIS link corresponding to the wireless communication link serial number. The master device configures the start time of the slave device data packet to ensure that the slave device data packet sending time slots of each slave device do not overlap with each other.

[0209] like Fig.10 It is the control data of the access termination command HIS Terminate, including a 1-byte HIS sequence number (HIS Seq) to be terminated, the reason for terminating the HIS link (Reason), a 6-byte device address (Device Address) of the slave device whose HIS link is terminated, and a 2-byte effective time (Instant), i.e., the lower 16 bits of the HIG event counter (HIG Event Counter). Generally, the HIG master device sends an access termination command to the slave device to disconnect the HIS link. If the access termination command sent by the HIG master device configures HIS Seq to 0xFF, all HIS links will be disconnected. The HIG slave device can also send an access termination command to the HIG master device to request to disconnect its own HIS link. The time slot when the HIG slave device sends the access termination command is the time slot when the HIG slave device sends the slave device data packet HISS PDU. After receiving the access termination command sent by the HIG slave device, the HIG master device can also choose to send an access termination command in the control time slot HIGC PDU time slot to confirm the disconnection of the HIS link of the corresponding slave device.

[0210] In some embodiments, there are three reasons for disconnecting the HIS link: 0x01 indicates that the link resources are insufficient and a new device needs to be connected, and the connection is disconnected; 0x02 indicates that the connection is disconnected due to abnormal reasons such as insufficient power; and 0x03 indicates that the power is turned off to disconnect all HIS links.

[0211] In some embodiments, Fig.11 The figure shows the process of a slave device accessing a wireless communication link and establishing a wireless link, taking the HIS link as an example. The slave device to be connected first searches for the broadcast packet sent by the master device to obtain synchronization information. After synchronization, it starts to receive the control packet sent by the master device. After receiving the control packet, the slave device determines whether there is a HIS random access command.

[0212] If there is no random access command, the control packet HIGC PDU sent by the master device continues to be received. If it is a random access command, the HIS random access command is received again after a certain period of random waiting, and a random access request command is sent after receiving the HIS random access command again.

[0213] After the slave device sends the random access request command, it continues to receive the control packet sent by the master device and determines whether it is a HIS access permission command. If the HIS access permission command is received, the HIS wireless communication link is established with the master device according to the HIS wireless link sequence number and access address of the HIS access permission command.

[0214] If no HIS random access command is received and the timeout occurs, the control packet sent by the master device continues to be received, such as receiving HIGC PDU under the HIS link and determining whether it is a HIS random access command, and starting a new round of access process.

[0215] If there is no timeout, continue to receive the control packet HIGC PDU sent by the master device and determine whether it is a HIS access permission command. Compared with the existing technology that uses multiple bidirectional CIS links, when accessing a new CIS slave device, the CIS master device needs to open a search window to search for the slave device. The more CIS links the CIS master device establishes, the fewer time slots are used to search for new slave devices, and the more difficult it is to establish a new CIS link or access a new slave device. In order to ensure that new slave devices can access quickly, the CIS master device must reserve sufficient search time slots, which will also reduce link efficiency. The slave device access method described in the present application requires fewer time slots and is highly efficient.

[0216] In some embodiments, Figure 5 The wireless point-to-multipoint two-way audio transmission system shown is a multi-player wireless gaming system, in which the slave device is a wireless gaming headset and the master device is a gaming console. The wireless gaming system can connect up to 4 wireless gaming headsets. Up to 4 wireless gaming headsets are wirelessly connected to the gaming console via a HIG formed by 4 HISs and transmit audio in both directions.

[0217] The sampling rate of the mono microphone of each wireless gaming headset is 48kHz, and the number of quantization bits is 16. The coding rate of the low complexity communication codec (LC3: Low Complexity Communication Codec) is 80kbps, the frame length is 10ms, and the size of each service data unit (SDU: Service Data Unit) is 100 bytes. Figure 2The time slot structure of the isochronous communication interval in the HIG protocol shown adopts the BLE 2Mbps transmission rate, the isochronous interval is 10ms, one data cycle corresponds to one SE interval, the SE interval is 3.1ms, and the number of retransmissions is K = 2. The air time occupied by the HISM PDU is 468us, the air time occupied by the HISS PDU is 460us, and the interval between each PDU is T_MSS, that is, 150us.

[0218] Fig.11As shown in the figure, it is the process of establishing the HIS link by the slave device accessing the HIG. Specifically, take the second slave device accessed as an example. The second slave device accessed first searches for the broadcast packet ADV PDU sent by the master device to obtain synchronization information. After synchronization, it starts to receive the control packet HIGC PDU sent by the master device. When the 39-bit HIG event counter (HIG EventCounter) is equal to 0x0201, the random access command HIS Random Access command sent by the master device is received, wherein the control code Opcode=0xD0 and the deadline Deadline is equal to 0x0300. After the slave device randomly waits for 10 equal time intervals, that is, when the HIG event counter is equal to 0x020B, it receives the random access command sent by the master device again, and sends the random access request HIS Access Request after a delay of 150us, wherein the control code Opcode=0xD1, the device address is 0x0102030405060708, and the maximum duration Duration is equal to the air time occupied by the slave device data packet HISS PDU 460us. After randomly waiting for 5 equal time intervals, that is, when the HIG Event Counter is equal to 0x0210, the random access command sent by the master device is received again, and a random access request t is sent after a delay of 150us. After randomly waiting for 20 equal time intervals, that is, when the HIG Event Counter is equal to 0x0224, the random access command sent by the master device is received again, and a random access request is sent after a delay of 150us. That is, the slave device sends three random access requests before the deadline, so that the master device can reliably receive the random access request. After the Deadline, that is, when the HIG Event Counter is equal to 0x0308, 0x0309, 0x030A, 0x030B, and 0x030C, the master device sends the HIS Access Permit command five times in succession, where Opcode = 0xD2, HISSeq is equal to 0x01, the device address is the address of the second slave device connected 0x0102030405060708, the access address allowed is 0xA0B1C2D3, the start time Start Time is equal to 1228us, and the Instant is 0x0320.

[0219] Therefore, the second slave device receives the HIS Access Permit when the HIG Event Counter is equal to 0x0308, and starts to send HISS PDU to the master device when the HIG Event Counter is equal to 0x0320, thereby establishing the HIS link and accessing the HIG.

[0220] If the master device has established 4 HIS links and connected 4 wireless gaming headsets, but a new wireless gaming headset needs to be connected. The master device can send an access termination command (HIS Terminate) to disconnect one of the HIS links, for example, disconnect the second HIS link. Specifically, when the HIG Event Counter is equal to 0x1201, the master device sends HIS Terminate to the second connected device, where Opcode = 0xD3, HIS Seq is equal to 0x01, Reason is equal to 0x01, indicating that the link resources are insufficient and a new device needs to be connected and the connection is disconnected. The device address is 0x0102030405060708, Instant is equal to 0x1230, and it is sent 8 times in a row. When the second slave device receives HISTerminate, it disconnects the HIS link and exits HIG. After the HIG Event Counter is equal to 0x1231, the master device sends the HIS Random Access command again to facilitate the access of the new device.

[0221] In such Figure 2 In the extended header of the HISM PDU shown in FIG. 1 , HIGE is set to 1 and HIS Num is set to 4. The HIS MT of the master device data packet HISM PDU sent by sub-event SE0 in each equal time interval is set to [1,1,1,1,0,0,0,0,0,0,0]. Figure 6 In the HIG time slot structure shown, if the game console correctly receives the slave device data packets HISS PDU sent by all four wireless gaming head mounted devices within the first sub-event SE interval, the HIS MT of the HISM PDU sent in sub-event SE1 is set to [0,0,0,0,0,0,0,0,0,0,0]. If the game console does not correctly receive the HISS PDU of the second and fourth wireless gaming head mounted devices within a certain SE interval, the HIS MT of the HISM PDU sent in the next SE interval is set to [0,1,0,1,0,0,0,0,0,0,0].

[0222] exist Fig.12In the HIG master device's receiving and sending process shown, the game console confirms whether the HIS PDU sent by the wireless gaming headset is correctly received based on whether the NESN (Next Expected Sequence Number) in the received HISS PDU header is consistent with the HIG SN in the HIS MPDU extension header in the current equal time interval. If within a certain SE interval, all four wireless gaming headsets have correctly received the HIS MPDU sent by the game console, and the game console has also correctly received the HISS PDU sent by all wireless gaming headsets, or the number of retransmissions is equal to the maximum number of retransmissions, then the game console stops sending. Otherwise, the HISM PDU is sent repeatedly in the next SE interval.

[0223] In some embodiments, the present application provides a point-to-multipoint wireless audio bidirectional transmission device, which can be used as a master device (such as Figure 5 The master device M) in the embodiment of the present application can implement the single-point to multi-point wireless audio bidirectional transmission method provided in the first aspect, including:

[0224] Radio frequency transceiver module, used for receiving and sending wireless signals;

[0225] A baseband data and protocol processor is used to control the radio frequency transceiver module to communicate with the slave device based on an isochronous communication interval, wherein:

[0226] In the point-to-multipoint audio broadcast time slot of the isochronous communication interval, broadcast and send a master device data packet;

[0227] Broadcasting and sending synchronization information for synchronization of slave devices in an advertising time slot of the isochronous communication interval;

[0228] After the random access event is triggered, a random access window is opened; during the period when the random access window is open, a random access command is sent in the control time slot of the isochronous communication interval, and a random access request sent by a slave device is received; after the random access window is closed, a slave device that is allowed to access is determined, and an independent slave device data packet sending time slot is allocated to the slave device that is allowed to access in the multi-point-to-point audio transmission time slot; an access permission command is configured according to the random access request and the slave device data packet sending time slot; and the access permission command is sent in the control time slot to instruct the slave device that is allowed to access to establish a wireless communication link with the master device;

[0229] Based on the wireless communication link, a slave device data packet is received in each allocated slave device data packet transmission time slot.

[0230] In some embodiments, the present application provides a point-to-multipoint wireless audio bidirectional transmission device, which can be used as a slave device (such as Figure 5 The slave devices S1 to SK in the embodiment of the present application can implement a single-point to multi-point wireless audio bidirectional transmission method provided in the first aspect, including:

[0231] Radio frequency transceiver module, used for receiving and sending wireless signals;

[0232] A baseband data and protocol processor, used to control the radio frequency transceiver module to communicate with the master device, wherein: searching for synchronization information sent by the master device in the advertising time slot of the isochronous communication interval, and synchronizing with the master device according to the synchronization information;

[0233] After synchronization with the master device, receiving a random access command sent by the master device in a control time slot of the isochronous communication interval; sending a random access request to the master device in the control time slot during an open random access window of the master device according to the random access command;

[0234] After the random access window is closed, receiving an access permission command sent by the master device in the control time slot, and establishing a wireless communication link with the master device if the access permission command indicates that the slave device is allowed to access;

[0235] Based on the wireless communication link, wireless audio bidirectional transmission is performed with the master device, the master device data packet broadcasted by the master device is received in the point-to-multipoint audio broadcast time slot of the isochronous communication interval, and the slave device data packet is sent in the slave device data packet sending time slot allocated by the master device.

[0236] In some embodiments, reference Figure 5 The present application embodiment provides a point-to-multipoint wireless audio bidirectional transmission system, including:

[0237] The main device M provided in the embodiment of the present application;

[0238] At least 2 slave devices S1-SK provided in the embodiments of the present application.

[0239] like Fig.13As shown, in some embodiments, the wireless gaming head-mounted device of the wireless gaming system includes an audio input unit 131, an audio output unit 133, an audio processing unit 132, a baseband data and protocol processor 134, and a BLE radio frequency transceiver module 135. The audio input unit 131 collects external audio signals, voice or vocal music, and converts them into digital audio signals for transmission to the audio processing unit 132. The audio processing unit 132 performs post-processing such as noise reduction and gain control on the digital audio signals, and then compresses and encodes them into audio data. The audio processing unit 132 is also used to perform post-processing such as audio decoding, packet loss processing, equalization and sound effects on the audio data sent by the gaming console. The baseband data and protocol processor 134 executes the BLE protocol and the HIG protocol related to BLE Audio, processes the received master device data packet HISM PDU, and processes the audio data into a physical layer data packet PDU suitable for transmission by the BLE radio frequency transceiver module. It also processes the audio data packet sent by the wireless gaming head-mounted device received by the BLE radio frequency transceiver module and sends it to the audio processing unit. The audio output unit is used to convert the audio signal sent by the game console into a sound signal. The BLE radio frequency transceiver module is used for BLE wireless signal transmission and reception, including receiving the master device data packet HISM PDU and sending the slave device data packet HISS PDU.

[0240] like Fig.13 As shown, in some embodiments, the game console of the wireless game console system includes an audio output unit 133, an audio input unit 131, an audio processing unit 132, a baseband data and protocol processor 134, and a BLE radio frequency transceiver module 135. The baseband data and protocol processor executes the BLE protocol and the HIG protocol related to BLE Audio, processes the audio data packet sent by the wireless game head-mounted device received by the BLE radio frequency transceiver module, and sends it to the audio processing unit. According to the audio data provided by the audio processing unit, a master device data packet HISM PDU suitable for sending by the BLE radio frequency transceiver module is generated. The audio processing unit is also used to perform post-processing such as audio decoding, packet loss processing, equalization and sound effects on the audio data sent by the wireless game head-mounted device. The audio input unit collects external audio signals, voice or vocal music, and converts them into digital audio signals for transmission to the audio processing unit. The audio output unit is used to convert audio signals into sound signals. The BLE radio frequency transceiver module is used for BLE wireless signal transmission and reception, including sending the master device data packet HISM PDU and receiving the slave device data packet HISS PDU.

[0241] Please refer to Fig.14An embodiment of the present invention further provides an electronic device 14, including a processor 141, a memory 142, and a computer program stored in the memory 142 and executable on the processor 141. When the computer program is executed by the processor 141, the various processes of the embodiment of the multi-point to single-point wireless audio transmission method described above are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be described here.

[0242] The embodiment of the present invention further provides a readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, each process of the embodiment of the multi-point to single-point wireless audio transmission method described above is implemented, and the same technical effect can be achieved. To avoid repetition, it is not repeated here. The readable storage medium is, for example, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0243] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0244] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0245] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection created by this application.

Claims

1. A point-to-multipoint wireless audio bidirectional transmission method, characterized in that: include: The isochronous communication interval used for the wireless audio bidirectional transmission includes an advertising time slot, a control time slot, a point-to-multipoint audio broadcast time slot, and a multipoint-to-point audio transmission time slot; In the point-to-multipoint audio broadcast time slot, the master device broadcasts and sends a master device data packet; In the advertising time slot, the master device broadcasts and sends synchronization information for synchronization of the slave device; After the random access event is triggered, the master device opens a random access window; during the opening of the random access window, the master device sends a random access command in the control time slot and receives a random access request sent by the slave device; after the random access window is closed, the master device determines the slave device that is allowed to access, and allocates an independent slave device data packet sending time slot for the slave device that is allowed to access in the multi-point-to-point audio transmission time slot; the master device configures an access permission command according to the random access request and the slave device data packet sending time slot, and sends the access permission command in the control time slot to instruct the slave device that is allowed to access to establish a wireless communication link with the master device; The master device receives the slave device data packet in each allocated slave device data packet sending time slot based on the wireless communication link.

2. The point-to-multipoint wireless audio bidirectional transmission method according to claim 1, characterized in that: The step of allocating an independent slave device data packet transmission time slot to the slave device that is allowed to access in the multi-point-to-point audio transmission time slot comprises: In the multi-point-to-point audio transmission time slot, allocating a slave device data packet transmission time slot to the slave device that is allowed to access, so that the slave device data packet transmission time slots of each slave device that is allowed to access do not overlap with each other; The master device configures the access permission command, including: configuring the access permission command to carry the slave device data packet sending time slot indication information.

3. The point-to-multipoint wireless audio bidirectional transmission method according to claim 2, characterized in that: The allocating an independent slave device data packet sending time slot for the slave device allowed to access in the multi-point-to-point audio transmission time slot includes: obtaining a maximum duration occupied by a slave device data packet from a random access request sent by the slave device allowed to access, and allocating a slave device data packet sending time slot for the slave device allowed to access according to the maximum duration occupied by the slave device data packet; The slave device data packet sending time slot indication information is the sending start time point of the slave device data packet.

4. The point-to-multipoint wireless audio bidirectional transmission method according to claim 1, characterized in that: The master device determines the slave device that is allowed to access, and further includes allocating a wireless communication link to the slave device that is allowed to access; The master device configures the access permission command, further comprising: configuring the access permission command according to the wireless communication link allocation information of the slave device that is allowed to access, so that the access permission command carries the wireless communication link allocation information of the slave device that is allowed to access.

5. The point-to-multipoint wireless audio bidirectional transmission method according to claim 4, characterized in that: The wireless communication link information includes: one or more of a serial number of the wireless communication link allocated to the slave device allowed to access, an access address, and an effective time of the access permission.

6. The point-to-multipoint wireless audio bidirectional transmission method according to claim 1, characterized in that: The random access request includes a device address of the slave device; The master device configures the access permission command, further comprising: the master device obtains the device address of the slave device that is allowed to access, and sets the device address as the address of the slave device that is allowed to access in the access permission command.

7. The point-to-multipoint wireless audio bidirectional transmission method according to claim 1, characterized in that: Also includes: In the control time slot, the master device sends a random access termination command to disconnect the wireless communication link with the designated slave device, or, In the control time slot, when the master device receives the random access termination command sent by the slave device, it disconnects the wireless communication link with the slave device.

8. The point-to-multipoint wireless audio bidirectional transmission method according to any one of claims 1 to 7, characterized in that: The control time slot includes a master device sending time slot and a slave device sending time slot; the master device sends the random access command, access permission command or random access termination command in the master device sending time slot, and receives the random access request or random access termination command sent by the slave device in the slave device sending time slot; The synchronization information includes one or more of the time slot structure information of the isochronous communication interval, the starting time point of the isochronous communication interval, the duration of the isochronous communication interval, the frequency hopping sequence, the channel information, and the clock synchronization signal; In the advertising time slot, the master device broadcasts the synchronization information via a Bluetooth low energy advertising packet; The master device generates a master device control packet based on a Bluetooth low energy control protocol data unit, and transmits the random access command, the access permission command and / or the random access termination command through the master device control packet; The master device data packet is a Bluetooth low energy broadcast isochronous stream protocol data unit with an extended header, and its payload is used to load the audio data sent by the master device to the slave device. Its header includes: An indication bit for indicating whether it is a Bluetooth low energy broadcast isochronous stream protocol data unit of the extended packet header; A first extension bit for indicating a master device data packet sequence number; A second extension bit for indicating the maximum number of accessible slave devices; The third extension bit of the slave device mapping table is used to indicate that a slave device data packet needs to be sent.

9. The point-to-multipoint wireless audio bidirectional transmission method according to claim 8, characterized in that: The wireless communication link is a hybrid isochronous stream communication link, The master device performs wireless audio bidirectional transmission with multiple slave devices that are allowed to access through a hybrid isochronous group consisting of multiple hybrid isochronous stream communication links, specifically including: In the point-to-multipoint audio broadcast time slot of each data cycle, the master device data packet is broadcast and sent; In each multi-point to point audio transmission time slot of each data cycle, receiving slave device data packets in each slave device data packet transmission time slot in turn; Until the number of retransmissions of the master device data packet reaches the preset maximum number of retransmissions, or the slave device data packets sent by all slave devices that are allowed to access are correctly received by the master device, or the master device data packet is correctly received by all slave devices that are allowed to access, stop rebroadcasting the master device data packet and end this round of data communication; Among them, one round of data communication is carried out at an isochronous communication interval, one round of data communication includes at least one data cycle, one data cycle includes a point-to-multipoint audio broadcast time slot and one or more slave device data packet sending time slots, and one slave device data packet sending time slot is allocated to a slave device that is allowed to access.

10. A point-to-multipoint wireless audio bidirectional transmission method, characterized in that: include: The isochronous communication interval used for the wireless audio bidirectional transmission includes an advertising time slot, a control time slot, a point-to-multipoint audio broadcast time slot, and a multipoint-to-point audio transmission time slot; The slave device searches for synchronization information sent by the master device in the advertising time slot, and synchronizes with the master device according to the synchronization information; After synchronization with the master device, receiving a random access command sent by the master device in the control time slot; and sending a random access request to the master device in the control time slot during an open random access window of the master device according to the random access command; receiving an access permission command sent by the master device in the control time slot after the random access window is closed, and establishing a wireless communication link with the master device if the access permission command indicates that the slave device is allowed to access; Based on the wireless communication link, wireless audio bidirectional transmission is performed with the master device, a master device data packet broadcasted by the master device is received in the point-to-multipoint audio broadcast time slot, and a slave device data packet is sent in the slave device data packet sending time slot allocated by the master device.

11. The point-to-multipoint wireless audio bidirectional transmission method according to claim 10, characterized in that: The random access command carries time information for indicating a random access window open period of the master device; or the synchronization information carries time information for indicating a random access window open period of the master device; The slave device determines the random access window opening period of the master device according to the random access command or synchronization information.

12. The point-to-multipoint wireless audio bidirectional transmission method according to claim 10, characterized in that: The sending a random access request to the master device in the control time slot during the period when the random access window of the master device is open according to the random access command includes: After receiving the random access command sent by the master device for the first time, during the period when the random access window of the master device is open, receiving the random access command sent by the master device during the period when the random access window is open after delaying at least once based on the random delay time; During the period when the random access window of the master device is open, when a random access command sent by the master device is received after a delay based on the random delay time, a random access request is sent to the master device in the control time slot.

13. The point-to-multipoint wireless audio bidirectional transmission method according to claim 12, characterized in that: The control time slot includes a master device transmission time slot and a slave device transmission time slot; The slave device receives the random access command in a sending time slot of the master device; The sending of the random access request to the master device within the control time slot includes: upon receiving a random access command sent by the master device after a delay based on the random delay time, sending the random access request to the master device in a slave device sending time slot within the control time slot.

14. The point-to-multipoint wireless audio bidirectional transmission method according to claim 10, characterized in that: The sending of the random access request to the master device within the control time slot includes: configuring the random access request to carry the device address of the slave device and / or the maximum duration occupied by the slave device data packet; After the random access window is closed, receiving an access permission command sent by the master device in the control time slot, and if the access permission command indicates that the slave device is allowed to access, establishing a wireless communication link with the master device, including: Obtaining the address of the slave device that is allowed to access from the access permission command, If the address of the slave device allowed to access is the same as the device address of the slave device, the wireless communication link is established with the master device.

15. The point-to-multipoint wireless audio bidirectional transmission method according to claim 10, characterized in that: The establishing of a wireless communication link with the master device comprises: obtaining wireless communication link information allocated by the master device to the slave device allowed to access from the access permission command, and establishing a wireless communication link with the master device based on the wireless communication link information.

16. The point-to-multipoint wireless audio bidirectional transmission method according to any one of claims 10 to 15, characterized in that: The slave device generates a slave device control packet based on a Bluetooth low energy control protocol data unit, and transmits the random access request or the random access termination command through the slave device control packet; The slave device generates a slave device data packet based on a Bluetooth low energy connection isochronous stream protocol data unit, and transmits audio data through the slave device data packet.

17. The point-to-multipoint wireless audio bidirectional transmission method according to claim 16, characterized in that: The wireless communication link is a hybrid isochronous stream communication link; The performing wireless audio bidirectional transmission with the main device based on the wireless communication link includes: According to the information in the master device data packet, it is determined whether to send the slave device data packet to the master device in the slave device data packet sending time slot allocated by the master device, or to resend the slave device data packet.

18. A point-to-multipoint wireless audio bidirectional transmission device, characterized in that: The device is a master device, capable of implementing the point-to-multipoint wireless audio bidirectional transmission method described in any one of claims 1 to 9, including: Radio frequency transceiver module, used for receiving and sending wireless signals; A baseband data and protocol processor is used to control the radio frequency transceiver module to communicate with the slave device based on an isochronous communication interval, wherein: In the point-to-multipoint audio broadcast time slot of the isochronous communication interval, broadcast and send a master device data packet; Broadcasting and sending synchronization information for synchronization of slave devices in an advertising time slot of the isochronous communication interval; After a random access event is triggered, a random access window is opened; during the period when the random access window is open, a random access command is sent in a control time slot of the isochronous communication interval, and a random access request sent from a slave device is received; After the random access window is closed, determine the slave device that is allowed to access, and allocate an independent slave device data packet sending time slot for the slave device that is allowed to access in the multi-point-to-point audio transmission time slot; configure an access permission command according to the random access request and the slave device data packet sending time slot; and send the access permission command in the control time slot to instruct the slave device that is allowed to access to establish a wireless communication link with the master device; Based on the wireless communication link, a slave device data packet is received in each allocated slave device data packet transmission time slot.

19. A point-to-multipoint wireless audio bidirectional transmission device, characterized in that: The device is a slave device, capable of implementing the single-point to multi-point wireless audio bidirectional transmission method according to any one of claims 10 to 17, comprising: a radio frequency transceiver module for receiving and sending wireless signals; A baseband data and protocol processor, used to control the radio frequency transceiver module to communicate with the master device, wherein: searching for synchronization information sent by the master device in the advertising time slot of the isochronous communication interval, and synchronizing with the master device according to the synchronization information; After synchronization with the master device, receiving a random access command sent by the master device in a control time slot of the isochronous communication interval; sending a random access request to the master device in the control time slot during an open random access window of the master device according to the random access command; After the random access window is closed, receiving an access permission command sent by the master device in the control time slot, and establishing a wireless communication link with the master device if the access permission command indicates that the slave device is allowed to access; Based on the wireless communication link, wireless audio bidirectional transmission is performed with the master device, the master device data packet broadcasted by the master device is received in the point-to-multipoint audio broadcast time slot of the isochronous communication interval, and the slave device data packet is sent in the slave device data packet sending time slot allocated by the master device.

20. A point-to-multipoint wireless audio bidirectional transmission system, characterized in that: include: The master device as claimed in claim 18; At least 2 slave devices as claimed in claim 19.

21. An electronic device, characterized in that: include: A processor, a memory, and a program stored in the memory and executable on the processor, wherein when the program is executed by the processor, the steps of the point-to-multipoint wireless audio bidirectional transmission method according to any one of claims 1 to 9 or any one of claims 10 to 17 are implemented.

22. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the single-point to multi-point wireless audio bidirectional transmission method are implemented.

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