Wireless audio playback system and system on chip

Abstract

The application relates to a wireless audio playing system and a system on chip. The wireless audio playing system comprises a master device and at least one slave device, and the master device and the slave device form multiple wireless networks with different time references via multiple wireless links. The master device splits audio data into audio data frames with fixed time length, sets expected synchronous playing time of the audio data frames, selects a wireless network for audio data frame transmission, determines starting time in each wireless network based on the expected synchronous playing time, and transmits the audio data frame, the starting time and network identification to each slave device in the wireless network. The slave device determines actual synchronous playing time of the audio data frame based on the starting time and the network identification, and plays the audio data frame at the actual synchronous playing time. The wireless audio playing system can more efficiently and reliably transmit audio data to multiple slave devices via multiple wireless networks and make the slave devices play the audio data synchronously.

Description

Technical Field

[0001] This application relates to the field of wireless communication technology, and more specifically, to a wireless audio playback system and a system-on-a-chip. Background Technology

[0002] With the development of communication technology, wireless audio technology has been widely used. In some wireless audio transmission systems, a master device can often distribute audio data to several slave devices in a large space or multiple corners or rooms, and enable each device to play the distributed audio data synchronously.

[0003] When master and slave devices are networked and distribute data via a single wireless link, the amount of audio data that can be transmitted is limited. This is especially true when the audio data contains multiple channels that need to be played synchronously; a single wireless link network often cannot meet the data transmission capacity requirements. Furthermore, the reliability of audio data transmission cannot be guaranteed, for example, if the single network is subject to interference.

[0004] In this scenario, equipping the master and slave devices with multiple wireless links can increase the data transmission capacity of the wireless audio transmission system and improve its anti-interference capability. However, when multiple wireless links are of different modes (i.e., each wireless link uses different types of wireless transmission methods, including but not limited to WiFi, BT, BLE, etc.), the wireless networks built via these links also have different time bases, and each network typically operates and is maintained independently. In this situation, how to ensure synchronized playback of the transmitted audio data when multiple wireless networks in a multi-mode simultaneously transmit audio data from several channels is a problem that current technology has not yet adequately solved. Summary of the Invention

[0005] This application is provided to address the aforementioned problems existing in the prior art.

[0006] There is a need for a wireless audio playback system and a system-on-a-chip that can effectively utilize multiple wireless links equipped on the master and slave devices to efficiently transmit large amounts of audio data, and enable each slave device to synchronously play the audio data at the same time.

[0007] According to a first aspect of this application, a wireless audio playback system is provided, comprising a master device and at least one slave device, wherein the master device has at least two wireless links, each slave device has at least one of the at least two wireless links, and the master device and the slave devices with corresponding wireless links form a wireless network with corresponding time bases. The master device is configured to split audio data into audio data frames of fixed length; set an expected synchronized playback time for the audio data frames with reference to a time base corresponding to a first wireless network among at least two wireless networks; select at least one wireless network to which the audio data frames will be transmitted; determine a start time in the wireless network corresponding to the expected synchronized playback time with reference to the time bases corresponding to the respective wireless networks to which the audio data frames will be transmitted; and transmit the audio data frames, along with the start time and the network identifier of the selected wireless network, to each slave device networked via the wireless network. The slave devices are configured to, upon receiving the audio data frames, determine the actual synchronized playback time of the audio data frames in the slave device based on the start time and the network identifier, and play the audio data frames at the actual synchronized playback time.

[0008] According to a second aspect of this application, a system-on-a-chip (SoC) for a master device in a wireless audio playback system is provided. The SoC includes an interface configured to acquire audio data. The SoC further includes a wireless communication module configured to enable the master device to establish wireless networks with corresponding time bases for slave devices based on at least two wireless links. The SoC also includes a processor core configured to: acquire audio data from the interface; divide the audio data into audio data frames of fixed length; set an expected synchronized playback time for the audio data frames with reference to a time base corresponding to a first wireless network among at least two wireless networks; select at least one wireless network to which the audio data frames will be transmitted; determine a start time in the wireless network corresponding to the expected synchronized playback time with reference to the time bases corresponding to the wireless networks to which the audio data frames will be transmitted; and send the audio data frames, the start time, and the network identifier of the selected wireless network together to the wireless communication module. The wireless communication module is further configured to transmit the audio data frames from the processor core, along with the start time corresponding to the audio data frames and the network identifier of the selected wireless network, to each slave device networked via the corresponding wireless network.

[0009] According to a third aspect of this application, a system-on-a-chip (SoC) for a slave device in a wireless audio playback system is provided. The SoC includes a wireless communication module configured to enable the slave device to establish a wireless network with the master device and other slave devices based on at least one wireless link shared by the master device and other slave devices, having a corresponding time base; to receive audio data frames from the master device, and the start time and network identifier of the wireless network corresponding to the audio data frames. The SoC further includes a processor core configured to be connected to the audio playback module; to acquire audio data frames received via the wireless communication module, carrying the start time and the network identifier of the wireless network; to determine the actual synchronized playback time of the audio data frames based on the start time and the network identifier; and to control the audio playback module to play the audio data frames at the actual synchronized playback time.

[0010] Using the wireless audio playback system and system-on-a-chip according to various embodiments of this application, the master device and each slave device form multiple wireless networks through corresponding wireless links. When transmitting audio data frames to the corresponding slave devices through different wireless networks, the start time of the audio data frame in the transmitting wireless network is sent together. In this way, each slave device can determine the synchronous playback time of the audio data frame according to the wireless network receiving the audio data frame and the corresponding start time, thereby ensuring that the audio data frames transmitted through multiple wireless networks can be played synchronously at the same time. Attached Figure Description

[0011] In drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with or without letter suffixes may indicate different instances of similar parts. The drawings illustrate various embodiments generally by way of example rather than limitation, and are used, together with the description and claims, to explain the disclosed embodiments. Where appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the apparatus or method.

[0012] Figure 1 A schematic diagram showing a portion of the components of a wireless audio playback system according to an embodiment of this application is provided.

[0013] Figure 2 This diagram illustrates the process of transmitting multi-channel audio data in a wireless audio playback system according to an embodiment of this application.

[0014] Figure 3 This diagram illustrates a partial block diagram of the system-on-chip (SoC) of a master device in a wireless audio playback system according to an embodiment of this application.

[0015] Figure 4 This diagram illustrates a partial composition block diagram of a slave device's system-on-a-chip and its peripheral components in a wireless audio playback system according to an embodiment of this application. Detailed Implementation

[0016] To enable those skilled in the art to better understand the technical solutions of this application, the application will be described in detail below with reference to the accompanying drawings and specific embodiments. The embodiments of this application will be further described in detail below with reference to the accompanying drawings and specific examples, but these are not intended to limit the scope of this application.

[0017] The terms "first," "second," and similar words used in this application do not indicate any order, quantity, or importance, but are merely used for distinction. Words such as "including" or "comprising" mean that the element preceding the word encompasses the elements listed after it, and do not exclude the possibility of encompassing other elements as well. The execution order of the steps in the method described in conjunction with the accompanying drawings in this application is not intended to be limiting. As long as the logical relationship between the steps is not affected, several steps can be integrated into a single step, a single step can be decomposed into multiple steps, and the execution order of the steps can be changed according to specific needs.

[0018] It should also be understood that the term "and / or" in this application is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Furthermore, the character " / " in this application generally indicates that the preceding and following related objects have an "or" relationship.

[0019] According to embodiments of this application, a wireless audio playback system is provided. Figure 1 A schematic diagram showing a portion of the components of a wireless audio playback system according to an embodiment of this application is provided.

[0020] like Figure 1 As shown, the wireless audio playback system 100 includes a master device 101 and at least one slave device, such as slave device 111, slave device 112, slave device 113, and slave device 121. In other embodiments, the number of slave devices may be more or less. Figure 1 The number of slave devices shown. For example... Figure 1 As shown, the master device 101 has at least two wireless links, such as wireless link L1 and wireless link L2, and each slave device has at least one of the at least two wireless links L1 and wireless link L2, so as to Figure 1Taking the slave devices as an example, slave devices 111 and 112 both have wireless links L1 and L2, while slave device 113 may only have wireless link L1, and slave device 121 may only have wireless link L2. In other embodiments, each slave device may have the same multiple wireless links as the master device 101. Furthermore, the master device 101 and the slave devices with corresponding wireless links form wireless networks with corresponding time bases. For example, the master device 101 and slave devices 111, 112, and 113 form a wireless network N11 via a common wireless link L1; the master device 101 and slave devices 111, 112, and 121 form a wireless network N22 via a common wireless link L2, and wireless networks N11 and N22 have their own time bases. In some embodiments, wireless links L1, L2, etc., may be, for example, a WiFi link and LE Audio. As an example only, when the wireless network N11 is a WiFi wireless network, the TSF (Time Sync Function) timestamp in the WiFi network can be used as its time reference. When the wireless network N22 is an LE Audio network, the CIG (Connected Isochronous Group) timestamp in the LE Audio BIS network can be used as its time reference. These are not listed one by one here.

[0021] In other embodiments, the wireless link can also be other links that can meet the bandwidth requirements of audio data transmission, such as classic Bluetooth links, custom private wireless links, etc., and this application does not limit this. In addition, for networking methods without synchronization timestamps, a custom time synchronization protocol can be defined to send the system time of the master device 101 to each slave device, so that each slave device can fine-tune its system time according to the time overhead of the transmission process after receiving the time synchronization data, so as to ensure that the system time between the master device 101 and each slave device is as aligned as possible.

[0022] In some embodiments, in order to transmit audio data to each slave device, the master device 101 may be configured to first split the audio data into audio data frames of fixed duration. To reduce the bandwidth requirements, the audio data frames may employ a compressed encoding format. The encoding method can be lossless or lossy; this application does not limit this, as long as the encoding and decoding process does not affect the playback duration of the audio data. Furthermore, the audio data transmitted by the master device 101 to each slave device may be obtained from other audio sources via a wired connection such as USB or a wireless connection such as WiFi, or it may be downloaded from a remote website, server, or other means via an Ethernet interface; this application does not limit this either.

[0023] For a specific audio data frame, the master device 101 can also be configured to set the expected synchronized playback time of the audio data frame with reference to a time base corresponding to a first wireless network among at least two wireless networks. In some embodiments, with Figure 1 For example, either wireless network N11 or wireless network N22 can be selected as the first wireless network. Assuming that the master device 101 selects wireless network N11 as the first wireless network, the expected synchronous playback time of the audio data frame can be set with reference to the time base of wireless network N11. The expected synchronous playback time of the audio data frame can be a future point in time in the system time of the first wireless network. In addition, the expected synchronous playback time of the audio data frame can be predetermined and appropriately adjusted according to the actual situation, taking into account the transmission latency of each wireless networking system, especially the transmission latency of the wireless network with the largest transmission latency, as well as the channel latency required for playing audio data using software and the buffer data duration required to offset wireless link bandwidth jitter.

[0024] In other embodiments, the master device 101 may be further configured to select at least one wireless network to which the audio data frame will be transmitted, determine the start time in that wireless network corresponding to the expected synchronized playback time by referring to the time base corresponding to each wireless network to which the audio data frame will be transmitted, and transmit the audio data frame together with the start time and the network identifier of the selected wireless network to each slave device networked via that wireless network. Figure 1 For example, the main device 101 can choose to transmit the data frame in one or more wireless networks, such as wireless network N11 and wireless network N22. Assuming the main device 101 chooses to transmit the data frame in wireless network N11 (which is the first wireless network), the expected synchronized playback time can be directly used as the start time in wireless network N11. However, if the main device 101 chooses to transmit the data frame in wireless network N22, since wireless network N22 and wireless network N11 have different time bases, it is necessary to further refer to the time base of wireless network N22 to determine the start time in wireless network N22 corresponding to the expected synchronized playback time. It is worth noting that the wireless network used to transmit a specific audio data frame does not necessarily include the first wireless network. For example, although wireless network N11 is used as the first wireless network to set the expected synchronized playback time of the audio data frame, the wireless network to which the audio data frame is to be transmitted is not required to include wireless network N11. Furthermore, the first wireless network can be preset or changed by the user as needed; this application does not impose any restrictions on this.

[0025] In some embodiments, the slave device can be configured to, upon receiving the audio data frame, determine the actual synchronized playback time of the audio data frame in the slave device based on the start time and the network identifier, and play the audio data frame at the actual synchronized playback time. As an example only, when the slave device 111 receives an audio data frame with the network identifier of the wireless network N11 and the start time, it can refer to the time base used by the audio playback component in the slave device 111 to convert the start time into the actual synchronized playback time. This ensures that the slave device 111 has the same time base when playing each received audio data frame, thereby guaranteeing the continuity of audio data playback within the same slave device and improving audio playback quality.

[0026] By utilizing the wireless audio playback system according to various embodiments of this application, a master device can transmit audio data frames to different slave devices via multiple wireless networks. By sending the wireless network identifier and the start time in the corresponding wireless network along with the audio data frame, each slave device can accurately determine the actual playback time of the audio data frame in its device. This ensures the continuity of playback of various audio data frames on the same device, and also ensures that audio data frames transmitted via multiple wireless networks can be played synchronously on different devices.

[0027] In some embodiments, the slave device may be further configured to, when the slave device has multiple wireless links and receives audio data frames via multiple wireless networks, determine the actual synchronized playback time of the audio data frames based on the start time and the network identifier, with reference to a pre-set time base of a reference wireless network. For a slave device with multiple wireless links and simultaneously located in multiple wireless networks, one wireless network can be pre-set as the reference wireless network. When different audio data frames are received via multiple wireless networks, especially when audio data frames are received via other wireless networks besides the reference wireless network, the start time in the other wireless networks is first converted into the actual synchronized playback time with reference to the time base of the reference wireless network. This avoids problems such as audio playback stuttering caused by time base errors when playing audio data frames received via different wireless networks. Furthermore, the reference network can be pre-set or changed by the user as needed; this application does not impose any restrictions on this.

[0028] In some embodiments, the slave device may be further configured to first determine the second wireless network used for the transmission of the audio data frame based on the network identifier received together with the audio data frame, and then convert the start time in the second wireless network into the start time in the reference wireless network based on the time base of the reference wireless network and the second time base corresponding to the second wireless network, and use the start time as the actual synchronous playback time of the audio data frame.

[0029] More specifically, the device can further convert the start time in the second wireless network to the start time in the reference wireless network according to the following formula (1):

[0030] T1_start = T2_start–(T2 - T1) Formula (1)

[0031] Wherein, T2_start is the start time of playback in the second wireless network received together with the audio data frame, T2 is the second system time with reference to the second time base of the second wireless network, T1 is the first system time with reference to the time base of the reference wireless network, and T1_start is the start time with reference to the time base of the reference wireless network.

[0032] Normally, different wireless networks have different time bases. Each wireless network's time base operates and is maintained independently. The time bases of the same wireless network in the master device / each slave device can usually be aligned well with small errors between them. However, the errors in different wireless networks may be larger. Therefore, by using the system time difference (T2-T1) of different wireless networks in the above formula (1), the start time of the audio data frames received from different wireless networks is converted into the start time under a unified time base. In this way, the problem of discontinuous audio playback on the same device and asynchronous audio playback on different devices when each audio data frame is played using the time base of different networks is effectively avoided when there are certain differences between different time bases. This further improves the effect of synchronized audio playback.

[0033] In other embodiments, the master device may be further configured to play the audio data frame synchronously with the slave devices at the expected synchronized playback time. Since the start time of the audio data frame transmitted in each wireless network is determined based on the expected synchronized playback time, the master device can maintain synchronization with each slave device when playing the audio data frame at the expected synchronized playback time.

[0034] In some embodiments, the audio data to be played synchronously by the wireless audio playback system according to this application may include multiple channels. Figure 2 This diagram illustrates the process of transmitting multi-channel audio data in a wireless audio playback system according to an embodiment of this application.

[0035] like Figure 2 As shown, when the audio data to be played synchronously by the wireless audio playback system contains multiple channels, the main device can first divide the audio data into multiple channel groups in step 201. In some embodiments, each channel group may contain the same number of channels. In other embodiments, the number of channels contained in each channel group may be different, and this application does not limit this.

[0036] Then, in step 202, the master device splits the audio data of each channel group into audio data frames of fixed time length.

[0037] Next, in step 203, the master device can select different wireless networks to transmit audio data frames for different channel groups, ensuring that the audio data frames of each channel group have the expected uniform and synchronized playback time. Specifically, in conjunction with... Figure 1 The implementation is similar. For example, the expected unified synchronous playback time of audio data frames of each channel group can be set by referring to the time base corresponding to the first wireless network in at least two wireless networks, which will not be elaborated here.

[0038] In step 204, when the device receives audio data frames of different channel groups via different wireless networks, the actual unified synchronous playback time of the audio data frames of each channel group is determined based on the start time and network identifier corresponding to the different wireless networks, and the audio data frames of each channel in each channel group are played at the actual unified synchronous playback time.

[0039] Multichannel audio data is often large in volume. Dividing it into multiple channel groups and using multiple different wireless networks in the wireless audio playback system according to this application to transmit the audio data of different channel groups separately can reduce network bandwidth requirements, avoid network congestion, improve the overall transmission efficiency of audio data, reduce transmission latency, and enhance audio playback quality. Furthermore, the receiving slave device can determine the unified synchronous playback time of each channel's audio data based on the network identifier and corresponding start time received along with the audio data frames of the channel groups. Depending on the audio playback task undertaken by the device, it can synchronously play some or all of the audio data frames of each channel with other devices at that time. In other words, the wireless audio playback system according to this application, when transmitting multichannel audio data, not only ensures synchronous playback of each channel but also, compared to a system with only one wireless link, offers advantages such as more efficient data transmission, lower transmission latency, higher audio playback quality, and a better user experience.

[0040] In other embodiments, to improve the utilization of each wireless network and further enhance the transmission efficiency of audio data, the audio data can be divided into multiple channel groups that match the available data transmission bandwidth of each wireless network, taking into account the bandwidth requirements of each channel. Furthermore, a wireless network matching the bandwidth requirements of each channel group is selected for transmitting the corresponding audio data frames. That is, the channel group division does not necessarily have to be uniform. When there is a significant difference in the data transmission bandwidth between multiple wireless networks, or when some wireless networks are using part of their bandwidth for other data transmission tasks, resulting in limited available data transmission bandwidth, these situations can be considered when dividing the channel groups. This allows for a reasonable division of the audio data for each channel, ensuring that the bandwidth requirements of each wireless network are allocated in the most suitable way possible. In addition, appropriate audio data compression encoding will be selected based on the bandwidth of each wireless network. For example, LC3 encoding (Low Complexity Communications Codec) can be selected for LE Audio, while SBC encoding (Sub-band coding) or AAC encoding (Advanced Audio Coding) will be used for Classic Bluetooth, etc., which will not be listed here.

[0041] In other embodiments, not limited to the transmission of multi-channel audio data, when selecting a wireless network for transmission of audio data frames, the current available bandwidth of each wireless network can be obtained first, and a matching wireless network can be selected based on the bandwidth requirements of the audio data frame transmission. In some embodiments, "matching" may refer to, for example, the wireless network whose available bandwidth is closest to the bandwidth requirements of the audio data frame transmission, or the wireless network that is currently the most "idle" while meeting the bandwidth requirements of the audio data frame transmission, etc. The rules for selecting wireless networks can be preset or changed by the user as needed, and this application does not impose any restrictions on this.

[0042] In some embodiments, the master device may also be configured to monitor the network transmission quality of each wireless network and select at least one wireless network from which the audio data frame will be transmitted based on the network transmission quality of each wireless network. Specifically, for example, a wireless network with a network transmission quality higher than a first threshold may be selected as the wireless network from which the audio data frame will be transmitted. Optionally or additionally, if the network transmission quality of the wireless network used to transmit the audio data frame is lower than a second threshold, the wireless network transmitting the audio data may be switched to a wireless network with a network transmission quality higher than the first threshold, wherein the second threshold is lower than the first threshold. The network transmission quality may be characterized, for example, by measurements of one or more related indicators such as packet error rate, packet loss rate, signal-to-noise ratio, and data transmission delay in the corresponding wireless network by the master device or the slave device, or by calculation based thereon, which will not be described in detail here. By reasonably setting the first threshold and the second threshold, frequent network switching due to small fluctuations in the network transmission quality of the wireless network transmitting the audio data frame, as well as unnecessary network resource overhead caused by frequent network switching, can be avoided.

[0043] The above-mentioned strategy of selecting or switching the matching wireless network for audio data frames based on the available bandwidth and network transmission quality can be used alone or in combination to maximize the transmission efficiency and quality of audio data frames. Furthermore, based on the principle that each wireless network can be utilized as rationally as possible, the same audio data frame or audio data frames of different channels transmitted through different wireless networks can be played synchronously at the same time with higher reliability.

[0044] According to embodiments of this application, a system-on-a-chip (SoC) for a master device in a wireless audio playback system is also provided. Figure 3 This diagram illustrates a partial block diagram of the system-on-chip (SoC) of a master device in a wireless audio playback system according to an embodiment of this application.

[0045] exist Figure 3 China still Figure 1 Taking the main device 101 as an example, the system-on-a-chip 300 used for the main device 101 may include at least an interface 301, a wireless communication module 302, and a processor core 303.

[0046] Specifically, interface 301 may be configured to acquire audio data, for example. Interface 301 may include network adapters, cable connectors, serial connectors, USB connectors, parallel connectors, high-speed data transmission adapters (such as fiber optic, USB 3.0, Thunderbolt interfaces, etc.), wireless network adapters (such as WiFi adapters), telecommunications (3G, 4G / LTE, etc.) adapters, etc., and this application does not limit them.

[0047] The wireless communication module 302 can be configured to enable the master device 101 to operate on at least two wireless links. Figure 3 Each wireless link in the wireless link (L1 and L2) and the slave devices with corresponding wireless links (including slave device 111, slave device 121, etc., which are not listed here) form a wireless network with a corresponding time base (wireless network N11 corresponds to wireless link L1, and wireless network N22 corresponds to wireless link L2).

[0048] The processor core 303 can be configured, for example, to acquire audio data from interface 301 via a dedicated data bus such as an I2S bus (Inter-IC Sound bus, also known as an integrated circuit built-in audio bus), then split the audio data into audio data frames of fixed length, and set the expected synchronized playback time of the audio data frames with reference to the time base corresponding to a first wireless network among at least two wireless networks. The first wireless network can be any of the various wireless networks, such as wireless network N11 or wireless network N22; this application does not impose any limitation on this. The processor core 303 is also configured to select at least one wireless network to which the audio data frames will be transmitted, and determine the start time in that wireless network corresponding to the expected synchronized playback time with reference to the time base corresponding to each wireless network to which the audio data frames will be transmitted. The processor core 303 then sends the audio data frames, the start time, and the network identifier of the selected wireless network to the wireless communication module 302.

[0049] The wireless communication module 302 can be further configured to transmit the audio data frame from the processor core 303, along with the start time corresponding to the audio data frame and the network identifier of the selected wireless network, to each slave device in the corresponding wireless network.

[0050] According to embodiments of this application, a system-on-a-chip (SoC) for a slave device in a wireless audio playback system is also provided. Figure 4 This diagram illustrates a partial block diagram of a system-on-a-chip (SoC) and its peripheral components in a slave device within a wireless audio playback system according to an embodiment of this application. Figure 4 As shown, the system-on-chip 400 for use with device 111 may include at least a wireless communication module 402 and a processor core 403.

[0051] The wireless communication module 402 can be configured to enable the slave device 111 to establish a wireless network with corresponding time bases with the master device 101 and other slave devices based on various wireless links in at least one wireless link shared by the master device 101 and other slave devices. For example, in Figure 4In this example, slave device 111 shares a common wireless link L1 with master device 101, slave device 112, etc. Therefore, a wireless network N11 with a corresponding time base can be formed based on wireless link L1 with master device 101, slave device 112, etc. Similarly, a wireless network N22 with a corresponding time base can be formed based on wireless link L2 with master device 101, slave device 121, etc., and so on.

[0052] The wireless communication module 402 can also be configured to receive audio data frames from the master device 101, as well as the start time and network identifier of the wireless network corresponding to the audio data frames.

[0053] The processor core 403 is configured to be connected to an audio playback module 4031, and to acquire audio data frames with start time and network identifier of wireless network received via wireless communication module 402, determine the actual synchronous playback time of the audio data frames based on the start time and the network identifier, and control the audio playback module 4031 to play the audio data frames at the actual synchronous playback time.

[0054] Processor core 303 and processor core 403 may include any of the Cortex A series processors, such as, but not limited to, Cortex A5, Cortex A7, Cortex A8, Cortex A9, or any of the Cortex M series processors, such as, but not limited to, Cortex M4, Cortex M7, Cortex M23, Cortex M33, Cortex M55, etc., which will not be elaborated here.

[0055] Furthermore, although exemplary embodiments have been described herein, their scope includes any and all embodiments based on this application that have equivalent elements, modifications, omissions, combinations (e.g., schemes with overlapping embodiments), adaptations, or changes.

[0056] The elements in the claims will be interpreted broadly based on the language used in the claims and are not limited to the examples described in this specification or during the implementation of this application, the examples of which will be interpreted as non-exclusive. Therefore, this specification and examples are intended to be considered merely illustrative, and the true scope and spirit are indicated by the claims and the full scope of their equivalents.

[0057] The order of the steps in this application is merely exemplary and not restrictive. The execution order of the steps can be adjusted without affecting the implementation of this application (without disrupting the logical relationship between the required steps), and the various embodiments obtained after the adjustment still fall within the scope of this application.

[0058] The above description is intended to be illustrative and not restrictive. For example, the above examples (or one or more of them) can be used in combination with each other. Other embodiments may be used by those skilled in the art upon reading the above description. Furthermore, in the above detailed description, various features may be grouped together to simplify the application. This should not be construed as an intention that a disclosed feature not claimed is necessary for any claim. Rather, the subject matter of the invention may be less than all the features of a particular disclosed embodiment. Thus, the claims are incorporated herein by reference as examples or embodiments, wherein each claim is an independent, separate embodiment, and these embodiments are contemplated as being able to be combined with each other in various combinations or arrangements. The scope of the invention should be determined by reference to the claims and the full scope of their equivalents.

Claims

1. A wireless audio playback system, characterized in that, It includes a master device and at least one slave device, wherein the master device has at least two wireless links, each slave device has at least one of the at least two wireless links, and the master device and the slave devices with corresponding wireless links constitute a wireless network with corresponding time bases. The main device is configured as follows: The audio data is split into audio data frames of fixed duration; The expected synchronized playback time of the audio data frame is set with reference to the time base corresponding to the first wireless network among at least two wireless networks; Select at least one wireless network to which the audio data frame will be transmitted, refer to the time base corresponding to each wireless network to which the audio data frame will be transmitted, determine the start time in the wireless network corresponding to the expected synchronized playback time, and transmit the audio data frame together with the start time and the network identifier of the selected wireless network to each slave device networked through the wireless network. The slave device is configured to: upon receiving the audio data frame, determine the actual synchronous playback time of the audio data frame in the slave device based on the start time and the network identifier, and play the audio data frame during the actual synchronous playback time; The audio data contains multiple channels. The main device is further configured as follows: The audio data is divided into multiple channel groups; wherein, taking into account the bandwidth requirements of each channel of the audio data, the audio data is divided into multiple channel groups that match the available data transmission bandwidth of each wireless network. The audio data of each channel group is split into audio data frames of fixed duration. Different wireless networks are selected to transmit audio data frames for different channel groups, and the audio data frames of each channel group have the expected uniform and synchronized playback time; wherein, a wireless network that matches the bandwidth requirements of each channel group is selected to transmit the audio data frames of the corresponding channel group. The slave device is further configured to: when receiving audio data frames of different channel groups via different wireless networks, determine the actual unified synchronous playback time of the audio data frames of each channel group based on the start time and network identifier corresponding to the different wireless networks, and play the audio data frames of each channel in each channel group at the actual unified synchronous playback time.

2. The wireless audio playback system according to claim 1, characterized in that, The slave device is further configured as follows: When the slave device has multiple wireless links and receives audio data frames via multiple wireless networks, the actual synchronized playback time of the audio data frame is determined based on the start time and the network identifier, with reference to a pre-set time base of the reference wireless network.

3. The wireless audio playback system according to claim 2, characterized in that, The slave device is further configured as follows: The second wireless network used for the transmission of the audio data frame is determined based on the network identifier. The start time in the second wireless network is converted into the start time in the reference wireless network based on the time base of the reference wireless network and the second time base corresponding to the second wireless network, and used as the actual synchronous playback time of the audio data frame.

4. The wireless audio playback system according to claim 3, characterized in that, The slave device is further configured to convert the start time in the second wireless network to the start time in the reference wireless network according to formula (1): T1_start = T2_start–(T2 - T1) Formula (1) Wherein, T2_start is the start time of playback in the second wireless network received together with the audio data frame, T2 is the second system time with reference to the second time base, T1 is the first system time with reference to the time base of the reference wireless network, and T1_start is the start time with reference to the time base of the reference wireless network.

5. The wireless audio playback system according to any one of claims 1-4, characterized in that, The main device is further configured as follows: The audio data frame is played synchronously with the slave device at the expected synchronized playback time.

6. The wireless audio playback system according to any one of claims 1-4, characterized in that, The main device is further configured as follows: The network transmission quality of each wireless network is monitored, and based on the network transmission quality of each wireless network, at least one wireless network is selected to transmit the audio data frame.

7. The wireless audio playback system according to claim 6, characterized in that, The main device is further configured as follows: Select a wireless network with a network transmission quality higher than a first threshold as the wireless network from which the audio data frame will be transmitted, and / or, If the network transmission quality of the wireless network used to transmit the audio data frame is lower than a second threshold, the wireless network transmitting the audio data is switched to a wireless network with a network transmission quality higher than a first threshold, wherein the second threshold is lower than the first threshold.

8. The wireless audio playback system according to any one of claims 1-4, characterized in that, The wireless link is either a WiFi link or LE Audio.

9. A system-on-a-chip for a master device in a wireless audio playback system as described in claim 1, characterized in that, The on-chip system includes: An interface configured to acquire audio data; The wireless communication module is configured to enable the master device to establish a wireless network with a corresponding time base with a slave device based on each of at least two wireless links. The processor core is configured as follows: Obtain audio data from the interface; The audio data is split into audio data frames of fixed duration; The expected synchronized playback time of the audio data frame is set with reference to the time base corresponding to the first wireless network among at least two wireless networks; Select at least one wireless network to which the audio data frame will be transmitted, refer to the time base corresponding to each wireless network to which the audio data frame will be transmitted, determine the start time in the wireless network corresponding to the expected synchronized playback time, and send the audio data frame together with the start time and the network identifier of the selected wireless network to the wireless communication module. The wireless communication module is further configured to transmit the audio data frame from the processor core, along with the start time corresponding to the audio data frame and the network identifier of the selected wireless network, to each slave device in the corresponding wireless network.

10. A system-on-a-chip for a slave device in a wireless audio playback system as described in claim 1, characterized in that, The on-chip system includes: The wireless communication module is configured to enable the slave device to establish a wireless network with corresponding time bases with the master device and other slave devices based on each of the at least one wireless link shared by the master device and other slave devices; and to receive audio data frames from the master device, as well as the start time of the audio data frames and the network identifier of the wireless network. The processor core is configured to be connected to an audio playback module; it acquires audio data frames received via the wireless communication module, which contain a start time and a network identifier of the wireless network; it determines the actual synchronous playback time of the audio data frames based on the start time and the network identifier; and it controls the audio playback module to play the audio data frames at the actual synchronous playback time.

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