Channel selection communication method, device and system of Bluetooth chip without crystal oscillator

Abstract

The invention discloses a channel selection communication method, device and system for a Bluetooth chip without a crystal oscillator, and the method comprises the steps: switching on a data path of a channel selection-free circuit when the Bluetooth chip without the crystal oscillator is powered on, and switching off the channel selection circuit; transmitting a host data packet received by the radio frequency unit to the channel-free selection circuit; generating a first synchronization sequence according to a data frame synchronization header in the host data packet by using a channel-free selection circuit; receiving a second synchronization sequence which is sent by the host device and represents the host data packet; determining a frequency offset value of the crystal oscillator-free Bluetooth chip relative to the host device according to the first synchronization sequence and the second synchronization sequence; performing frequency offset compensation on an oscillator in the Bluetooth chip without the crystal oscillator according to the frequency offset value; and switching a data path connected with the channel selection circuit so as to perform data interaction with the host equipment by utilizing the channel selection circuit. In conclusion, for the communication with the channel selection circuit, the probability of data loss caused by filtering of the target signal is reduced.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and more specifically to a channel selection communication method, apparatus, and system for a crystal oscillator-free Bluetooth chip. Background Technology

[0002] In the field of wireless communication, oscillator performance is crucial for communication systems. First, the oscillator needs to provide a stable and accurate clock signal to ensure precise synchronization of all modules within the wireless communication chip, thereby maintaining the stability and reliability of wireless communication. Second, the phase noise performance of the oscillator has a significant impact on the performance of the wireless communication system; therefore, low phase noise is necessary to ensure signal transmission quality. Thus, wireless communication SoC chips require oscillators that are stable, accurate, and possess good phase noise performance.

[0003] In order to provide an accurate reference frequency, the traditional solution uses an external quartz crystal oscillator (crystal oscillator) to generate the clock. Since the quartz crystal itself has a stable oscillation period, it can ensure the normal operation of the communication system.

[0004] However, crystal oscillators are one of the most common pain points in radio frequency (RF) layouts, often being the root cause of problems such as noise, crosstalk, or crystal frequency tuning issues. During product development, multiple PCB iterations and redesigns are frequently required to address these problems, increasing development costs and timelines. In practical applications, crystal oscillators often suffer from the following drawbacks: they are prone to noise, crosstalk, or insufficient crystal frequency tuning; they lead to an increase in the number of components and higher costs; quartz crystals increase PCB area, making them unsuitable for miniaturized devices (such as wearable devices and TWS earphones); and crystal oscillators consume power during operation, making them unsuitable for low-power devices.

[0005] Therefore, an internal oscillator can be used instead of a crystal oscillator to generate the clock. Specifically, wireless communication chips use an internal oscillator instead of a crystal oscillator to generate the clock. However, when using an internal oscillator, the frequency of the internal oscillator differs significantly from the standard frequency, i.e., frequency deviation, which causes the system to malfunction. Furthermore, for communication schemes with channel selection circuitry, the target signal is often filtered out, resulting in data loss and making it impossible to estimate the oscillator's frequency deviation.

[0006] Therefore, for communications with channel selection circuits, how to reduce the probability of data loss caused by the filtering out of target signals has become an urgent technical problem to be solved. Summary of the Invention

[0007] Based on the above situation, the main objective of this invention is to provide a channel selection communication method, apparatus and system without a crystal oscillator Bluetooth chip, so as to reduce the probability of data loss caused by the filtering of target signals in communication with channel selection circuits.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] In a first aspect, this embodiment discloses a channel selection communication method for a crystal-free Bluetooth chip, used in a crystal-free Bluetooth chip equipped with a channel selection circuit, wherein the crystal-free Bluetooth chip integrates a data path without a channel selection circuit, and the method includes:

[0010] Step S100: When the crystal-free Bluetooth chip is powered on, connect the data path without channel selection circuit and disconnect the channel selection circuit.

[0011] Step S200: The host data packet received by the radio frequency unit is transmitted to the channelless selection circuit, wherein the host data packet is a data packet wirelessly transmitted by the external host device.

[0012] Step S300: A first synchronization sequence is generated using a channelless selection circuit based on the data frame synchronization header in the host data packet. The first synchronization sequence is a local sequence.

[0013] Step S400: Receive a second synchronization sequence representing host data packets sent by the host device. The second synchronization sequence is the synchronization sequence of the host device at a standard frequency.

[0014] Step S500: Determine the frequency offset value of the crystal-free Bluetooth chip relative to the host device based on the first synchronization sequence and the second synchronization sequence.

[0015] Step S600: Perform frequency offset compensation on the oscillator in the crystalless Bluetooth chip according to the frequency offset value, so that the frequency of the crystalless Bluetooth chip is aligned with the frequency of the host device.

[0016] Step S700: Switch the data path of the channel selection circuit to use the channel selection circuit to perform data interaction with the host device.

[0017] Optionally, step S500 includes:

[0018] Step S510: Perform conjugate multiplication of the first synchronization sequence and the second synchronization sequence to obtain the set of phase differences between each sampling point of the first synchronization sequence and the second synchronization sequence;

[0019] Step S520: Calculate the frequency offset value of the crystalless Bluetooth chip relative to the host device based on the phase difference set.

[0020] Optionally, step S520 includes:

[0021] Step S521: Select the phase difference of a target element from the phase difference set as the target phase difference;

[0022] Step S522: Calculate the frequency offset value of the corresponding frequency point based on the target phase difference;

[0023] Step S523: Use the frequency offset value corresponding to the target phase difference as the frequency offset value of the crystalless Bluetooth chip relative to the host device.

[0024] Optionally, in step S521, the target element is not the first sampling point;

[0025] Between step S521 and step S522, the following is also included:

[0026] Step S511: Subtract the target phase difference from the phase difference of the first sampling point to obtain the target phase difference after removing the initial phase;

[0027] In step S522, the frequency offset value of the crystalless Bluetooth chip relative to the host device is calculated based on the target phase difference after removing the initial phase.

[0028] Optionally, step S500 further includes:

[0029] Step S530: Summing up the elements in the phase difference set to obtain the total phase difference;

[0030] Step S540: Determine whether the magnitude of the sum of phase differences is greater than a preset threshold; if it is greater than the preset threshold, then determine the frequency offset value calculated in step S520 as the final frequency offset value; if the magnitude of the sum of phase differences is less than the preset threshold, then return to re-execute steps S300, S400 and S500.

[0031] Optionally, between step S600 and step S700, the following step is further included:

[0032] Establish a wireless connection between the crystal-free Bluetooth chip and the host device without a channel selection circuit.

[0033] Secondly, this embodiment discloses a channel selection communication device for a crystal-free Bluetooth chip, used in a crystal-free Bluetooth chip with a channel selection circuit. The crystal-free Bluetooth chip integrates a data path without a channel selection circuit. The device includes:

[0034] The channelless connection module is used to connect the data path of the channelless selection circuit and disconnect the channel selection circuit when the Bluetooth chip without crystal oscillator is powered on.

[0035] The host data packet transmission module is used to transmit the host data packets received by the radio frequency unit to the channelless selection circuit, wherein the host data packets are data packets wirelessly sent by the external host device;

[0036] The first synchronization sequence module is used to generate a first synchronization sequence based on the data frame synchronization header in the host data packet using a channelless selection circuit. The first synchronization sequence is a local sequence.

[0037] The second synchronization sequence module is used to receive a second synchronization sequence representing host data packets sent by the host device. The second synchronization sequence is the synchronization sequence of the host device at a standard frequency.

[0038] The frequency offset determination module is used to determine the frequency offset value of the crystal-free Bluetooth chip relative to the host device based on the first synchronization sequence and the second synchronization sequence.

[0039] The frequency offset compensation module is used to compensate the frequency offset of the oscillator in the crystalless Bluetooth chip according to the frequency offset value, so as to align the frequency of the crystalless Bluetooth chip with the frequency of the host device.

[0040] The path switching module is used to switch the data path connected to the channel selection circuit so that the channel selection circuit can be used to interact with the host device.

[0041] Optionally, the frequency offset determination module includes:

[0042] The phase difference calculation unit is used to perform conjugate multiplication of the first synchronization sequence and the second synchronization sequence to obtain the sum of phase differences of each sampling point of the first synchronization sequence and the second synchronization sequence.

[0043] The frequency offset calculation unit is used to calculate the frequency offset of the crystalless Bluetooth chip relative to the host device based on the phase difference set.

[0044] Optionally, the frequency offset calculation unit is specifically used for:

[0045] Select the phase difference of a target element from the set of phase differences as the target phase difference;

[0046] Calculate the frequency offset value at the corresponding frequency point based on the target phase difference;

[0047] The frequency offset value corresponding to the target phase difference is used as the frequency offset value of the crystalless Bluetooth chip relative to the host device.

[0048] Optionally, the target element is not the first sampling point;

[0049] The frequency offset calculation unit is specifically used to: subtract the target phase difference from the phase difference of the first sampling point to obtain the target phase difference after removing the initial phase;

[0050] The frequency offset of the crystalless Bluetooth chip relative to the host device is calculated based on the target phase difference after removing the initial phase.

[0051] Optionally, the frequency offset determination module further includes:

[0052] The summation unit is used to sum the individual elements in the phase difference set to obtain the total phase difference.

[0053] The sum judgment unit is used to determine whether the magnitude of the sum of phase differences is greater than a preset threshold; if it is greater than the preset threshold, the module, the second synchronization sequence module, and the frequency offset value determination module will be activated.

[0054] Optionally, it also includes:

[0055] The connection establishment module is used to establish a wireless connection between the crystal-free Bluetooth chip and the host device in the absence of a channel selection circuit.

[0056] Thirdly, this embodiment discloses a computer device, including:

[0057] The method described in the first aspect is used for channel selection communication based on a crystal-free Bluetooth chip, or the apparatus described in the second aspect is used.

[0058] Fourthly, this embodiment discloses a computer-readable storage medium having a computer program stored thereon, the computer program stored in the storage medium being executed by a processor to implement the method of the first aspect described above.

[0059] Fifthly, this embodiment discloses a crystal-free Bluetooth chip having an integrated circuit designed to implement the method described in the first aspect above.

[0060] Sixthly, this embodiment discloses a channel selection communication system without a crystal oscillator Bluetooth chip, which has an integrated circuit, including:

[0061] Host equipment;

[0062] The crystal-free Bluetooth chip described in the fifth aspect above interacts with the host device for data exchange.

[0063] Beneficial effects:

[0064] According to embodiments of the present invention, a channel selection communication method, apparatus, and system for a crystal-free Bluetooth chip are disclosed. The crystal-free Bluetooth chip, which includes a channel selection circuit, integrates a data path without a channel selection circuit. When the crystal-free Bluetooth chip is powered on, the data path of the channel selection circuit is connected, and the channel selection circuit is disconnected. The host data packet received by the radio frequency unit is transmitted to the channel selection circuit. The channel selection circuit generates a local first synchronization sequence based on the data frame synchronization header in the host data packet. A second synchronization sequence representing the host data packet sent by the host device is received; the second synchronization sequence is the synchronization sequence of the host device at a standard frequency. Based on this, the frequency offset value of the crystal-free Bluetooth chip relative to the host device is determined according to the first and second synchronization sequences, and frequency offset compensation is performed on the oscillator in the crystal-free Bluetooth chip to align the frequency of the crystal-free Bluetooth chip with the frequency of the host device. Finally, the data path connected to the channel selection circuit is switched to enable data interaction with the host device using the channel selection circuit. Because host data packets are received via a data path without a channel selection circuit before establishing a communication connection, the information in these packets is not filtered out by the channel selection circuit. This means the entire content of the data packet is covered, enabling frequency offset estimation of the local oscillator and frequency offset compensation for the oscillator in the crystalless Bluetooth chip. This ensures the frequency of the crystalless Bluetooth chip is aligned with the host device's frequency. Then, the data path connected to the channel selection circuit is switched. This ensures frequency alignment with the host device, guaranteeing normal data transmission and reception. Furthermore, because of the frequency alignment, data packets (target signals) sent by the host device will not be mistakenly filtered out due to frequency offset falling outside the target channel. Additionally, since data interaction with the host device utilizes the channel selection circuit, the effect of filtering out information outside the target channel is preserved, thus improving the quality of the received signal. In summary, for communication using a channel selection circuit, the probability of data loss due to target signal filtering is reduced.

[0065] Other beneficial effects of the present invention will be explained in detail through the introduction of specific technical features and technical solutions in specific embodiments. Those skilled in the art should be able to understand the beneficial technical effects brought about by these technical features and technical solutions through the introduction of these technical features and technical solutions. Attached Figure Description

[0066] The embodiments of the present invention will now be described with reference to the accompanying drawings. In the drawings:

[0067] Figure 1 This is a schematic diagram of a crystal-free Bluetooth chip with a channel selection circuit disclosed in this embodiment;

[0068] Figure 2This is a flowchart of a channel selection communication method for a crystal-free Bluetooth chip disclosed in this embodiment;

[0069] Figure 3 This is a schematic diagram illustrating a data transmission and reception example of a channel selection circuit disclosed in this embodiment;

[0070] Figure 4 This is a schematic diagram of the channel selection communication device structure of a crystal-free Bluetooth chip disclosed in this embodiment;

[0071] Figure 5 This is a schematic diagram illustrating a data transmission and reception example without adding a channel selection path as disclosed in this embodiment. Detailed Implementation

[0072] The present invention is described below based on embodiments, but the present invention is not limited to these embodiments. In the following detailed description of the present invention, some specific details are described in detail, but well-known methods, processes, procedures, and elements are not described in detail in order to avoid obscuring the essence of the present invention.

[0073] Furthermore, those skilled in the art should understand that the accompanying drawings provided herein are for illustrative purposes only and are not necessarily drawn to scale.

[0074] Unless the context explicitly requires it, the words "comprising," "including," and similar terms throughout the specification and claims should be interpreted as encompassing rather than being exclusive or exhaustive; that is, meaning "including but not limited to."

[0075] In the description of this invention, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0076] To reduce the probability of data loss due to target signal filtering in communication systems with channel selection circuits, this embodiment discloses a channel selection communication method for crystal-free Bluetooth chips. This method is used with crystal-free Bluetooth chips that have channel selection circuits. In this embodiment, the crystal-free Bluetooth chip integrates a data path without channel selection circuits. Please refer to [reference needed]. Figure 1 , Figure 1This is a schematic diagram of a crystal-free Bluetooth chip with a channel selection circuit disclosed in this embodiment. The crystal-free Bluetooth chip includes a radio frequency (RF) unit 1, an analog-to-digital converter (ADC) unit 2, a channel selection circuit 3, and a channel selection circuit 4. The RF unit 1 is used for wireless signal transmission and reception with external devices via an RF antenna. The ADC unit 2 performs analog-to-digital conversion on the analog signal output by the RF unit 1. The channel selection circuit 3 filters out information outside the target channel from the signal received by the RF unit 1, retaining only the target signal, thereby improving the quality of the received signal. In this embodiment, frequency offset estimation and correction are performed by adding the channel selection circuit 4, as described below.

[0077] Please refer to Figure 2 , Figure 2 This is a flowchart of a channel selection communication method for a crystal-free Bluetooth chip disclosed in this embodiment. The channel selection communication method for the crystal-free Bluetooth chip includes steps S100, S200, S300, S400, S500, S600, and S700.

[0078] Step S100: When the crystal-less Bluetooth chip is powered on, the data path of the channel selection circuit is connected, and the channel selection circuit is disconnected. Please refer to... Figure 1 When the crystal-free Bluetooth chip is powered on, the switching switch S connects the radio frequency unit 1 and the channel-free selection circuit 4, so that the data / signals received by the radio frequency unit 1 are transmitted to the channel-free selection circuit 4 instead of the channel selection circuit 3.

[0079] Step S200: The host data packet received by the radio frequency unit is transmitted to the channelless selection circuit. In this embodiment, the host data packet is a data packet wirelessly transmitted by an external host device. In a specific embodiment, the host device transmits data packets at several preset frequency points. Specifically, the host device transmits data packets according to the standard Bluetooth protocol, typically using 32 frequency points: 0, 2, 4, 6, 8, 10, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77. During this period, when the frequency point of the radio frequency unit corresponds to the frequency point of the host device, data packets transmitted by the over-the-air host device can be received. In specific implementation, when there is a deviation between the high-speed oscillation frequency of the crystalless Bluetooth chip and the standard frequency of the host device, the ID packet (a type of data packet) transmitted by the host device in the query scan state can also be searched. Specifically, in the inquiry state, the host device sends ID packets on the aforementioned frequency points according to the standard Bluetooth protocol. During this period, the crystal-less Bluetooth chip, in the inquiry scan state, can search for the ID packets sent by the over-the-air host device in the inquiry state. The ID packets are then used to correct the oscillation frequency of the crystal-less SoC chip. After correcting the oscillation frequency of the crystal-less Bluetooth chip, it switches to the page state to establish a Bluetooth connection with the external host device and exchange data.

[0080] In this embodiment, since the host data packet is transmitted to the channelless selection circuit, meaning the circuit does not filter the signal, complete data information can be preserved. Therefore, the host data packet can be used for frequency offset estimation and subsequent frequency offset correction.

[0081] Step S300: Using a channelless selection circuit, a first synchronization sequence s is generated based on the data frame synchronization header in the host data packet. l Please refer to this. Figure 1 After receiving the host data packet, the synchronization calculation unit in the channelless selection circuit 4 can be used to generate the first synchronization sequence s. l Specifically, according to the Bluetooth standard protocol, before establishing a connection, the two communicating parties attempt to connect using a predefined algorithm. Therefore, according to the Bluetooth standard protocol, a first synchronization sequence s can be generated. l In this embodiment, the first synchronization sequence s is referred to as... l For a crystal-free Bluetooth chip, the local sequence is used. In a specific embodiment, due to the first synchronization sequence s l It is a local sequence, therefore, this synchronization sequence is not affected by environmental interference and is an ideal sequence. However, due to the frequency offset of the local crystal oscillator relative to the host device, this first synchronization sequence s lFrequency offset exists.

[0082] Step S400: Receive the second synchronization sequence s representing the host data packet sent by the host device. r In this embodiment, the so-called second synchronization sequence s r The second synchronization sequence s is the synchronization sequence of the host device at a standard frequency. Since it is assumed that the clock frequency of the host device is provided by a standard crystal oscillator, the second synchronization sequence s... r No frequency offset occurred. Please refer to this. Figure 1 After receiving the host data packet, the synchronization calculation unit in the channelless selection circuit 4 can obtain the second synchronization sequence s by parsing the host data packet. Specifically, according to the Bluetooth standard protocol, the synchronization header (SHR) loads the host device's clock frequency information. Therefore, after receiving data sent by an external host device (such as a mobile phone), the second synchronization sequence s can be obtained through the synchronization header (SHR) in the data packet. r .

[0083] In the specific implementation process, after obtaining the first synchronization sequence s l Second synchronization sequence s r Then, the frequency offset between the high-speed oscillation frequency of the crystalless Bluetooth chip and the clock frequency of the host device can be estimated.

[0084] Step S500, based on the first synchronization sequence s l Second synchronization sequence s r Determine the frequency offset of the crystal-free Bluetooth chip relative to the host device. In the specific implementation process, the first synchronization sequence s... l Second synchronization sequence s r Each has its own frequency information loaded; therefore, by analyzing the first synchronization sequence s... l Second synchronization sequence s r By conducting comparative analysis, the frequency offset value of the crystal-free Bluetooth chip relative to the host device can be obtained.

[0085] Step S600: Frequency offset compensation is performed on the oscillator in the crystal-less Bluetooth chip according to the frequency offset value, so that the frequency of the crystal-less Bluetooth chip is aligned with the frequency of the host device. Please refer to... Figure 1After obtaining the frequency offset value of the crystal-free Bluetooth chip relative to the host device, the frequency offset compensation unit in the channelless selection circuit 4 can be used to compensate for the frequency offset of the oscillator in the crystal-free Bluetooth chip. Specifically, the frequency offset compensation unit can adjust the division value of the frequency divider in the phase-locked loop (PLL) circuit of the crystal-free Bluetooth chip based on the frequency offset value to compensate for the output frequency offset of the oscillator, so that the high-speed oscillation frequency output by the PLL is close to the clock frequency of the host device. The PLL circuit is the phase-locked loop in the oscillator loop of the crystal-free Bluetooth chip. Generally, a phase-locked loop (PLL) consists of a phase detector, a loop filter, a VCO, and a frequency divider. The frequency output by the VCO is the high-speed oscillation frequency of the crystal-free Bluetooth chip, which is also the RF clock frequency of the crystal-free Bluetooth chip. In specific implementation, when the high-speed oscillation frequency is high, the division value of the frequency divider in the PLL is increased to reduce the high-speed oscillation frequency output by the VCO; when the high-speed oscillation frequency is low, the division value of the frequency divider in the PLL is decreased to increase the high-speed oscillation frequency output by the VCO.

[0086] Step S700: Switch the data path connected to the channel selection circuit to enable data interaction with the host device using the channel selection circuit. Please refer to... Figure 1 After frequency offset compensation is performed on the oscillator in the crystal-less Bluetooth chip to align its frequency with that of the host device, a connection can be established. At this point, the channel selection circuit 3 can be switched on using switch S, and the channel selection circuit 4 can be disconnected. Data transmission and reception are then performed using channel selection circuit 3. In this embodiment, using the data path of the channel selection circuit for data transmission and reception filters out information outside the target channel, retaining only the target signal, thereby improving the quality of the received signal. For details, please refer to... Figure 3 , Figure 3 This is a schematic diagram illustrating a data transmission and reception example of a channel selection circuit disclosed in this embodiment. The dashed box represents the channel of the channel selection circuit. Data falling within the channel indicated by the dashed box can be received, while data falling outside the channel indicated by the dashed box will be directly filtered out. Figure 3 As shown, channel selection circuit 3 only retains the target signal ( Figure 3 (As shown in the solid-line ellipse), this improves the quality of the received signal.

[0087] In a specific embodiment, step S500 includes: step S510, processing the first synchronization sequence s l With the second synchronization sequence s r Conjugate multiplication yields the first synchronization sequence s. l Second synchronization sequence s rThe phase difference set of each sampling point; Step S520, calculate the frequency offset value of the crystalless Bluetooth chip relative to the host device based on the phase difference set.

[0088] Specifically, Formula 1 can be used for conjugate multiplication:

[0089]

[0090] In the formula, s l This is the first synchronization sequence; s r This is the second synchronization sequence. It is s r The conjugate of complex numbers; s d The result of the conjugate multiplication of the first and second synchronization sequences is specifically a complex number. The set that constitutes the collection, and the individual elements in the set. The conjugate product of each sampling point has an imaginary part that carries the phase difference information of each sampling point, for example... In this context, Δθi represents the phase difference at the i-th sampling point. In practical implementation, since phase is related to frequency, the frequency difference, or frequency offset, can be estimated from the phase difference value. From this, the frequency offset of the crystal-free Bluetooth chip relative to the host device can be calculated.

[0091] To reduce data computation and improve communication efficiency, in an optional embodiment, step S520 includes: step S521, selecting the phase difference of a target element from the phase difference set as the target phase difference; step S522, calculating the frequency offset value of the corresponding frequency point based on the target phase difference; and step S523, using the frequency offset value corresponding to the target phase difference as the frequency offset value of the crystal-free Bluetooth chip relative to the host device. Specifically, since each sampling point uses the same oscillator or crystal, the frequency offset of each sampling point is consistent, that is, the frequency offset of the synchronization sequence is consistent. Therefore, only one element can be selected from the phase difference set of each sampling point, and the frequency offset of this element can represent the frequency offset of the entire sequence, thereby reducing data computation and improving communication efficiency. In a specific implementation, an element can be randomly selected from the phase difference set of each sampling point as the target element. After selecting the target element, the phase difference of the target element is used as the target phase difference, and the frequency offset value is calculated accordingly. This frequency offset value represents the frequency offset value of the crystal-free Bluetooth chip relative to the host device.

[0092] To avoid the influence of the initial phase, in an optional embodiment, in step S521, the target element is not the first sampling point; between steps S521 and S522, the method further includes: step S511, subtracting the target phase difference from the phase difference of the first sampling point to obtain the target phase difference after removing the initial phase; in step S522, calculating the frequency offset value of the crystal-free Bluetooth chip relative to the host device based on the target phase difference after removing the initial phase. Specifically, the frequency offset value can be calculated using the following formula 2:

[0093]

[0094] In the formula, f offset Let Δθ be the frequency offset value at the i-th sampling point, which represents the frequency offset of the crystal-free Bluetooth chip relative to the host device; i Let Δθ be the phase difference of the i-th sampling point, which is also the phase difference of the target element. i The magnitude can be obtained through the imaginary part of the i-th element in Formula 1; Δθ1 is the phase difference of the first sampling point, which is the initial phase, and this phase is a random phase; T s The sampling period of the signal is specifically the duration between two adjacent sampling points in the synchronization sequence. In this embodiment, by calculating the frequency offset of the crystal-free Bluetooth chip relative to the host device after removing the target phase difference from the initial phase, the impact of the initial phase randomness can be reduced, thereby improving the accuracy of the frequency offset calculation.

[0095] To verify whether the frequency offset compensation was successful, in an optional embodiment, step S500 further includes: step S530, summing the elements in the phase difference set to obtain the total phase difference s. sum Step S540: Determine the total phase difference s sum If the magnitude of the sum of phase differences is greater than a preset threshold, then the frequency offset value calculated in step S520 is determined as the final frequency offset value; if the magnitude of the sum of phase differences is less than a preset threshold, then steps S300, S400, and S500 are re-executed. Specifically, Formula 3 can be used to calculate the sum of phase differences s. sum The calculation is as follows:

[0096]

[0097] In the formula, s sum It is the sum of the phase differences of all elements in the phase difference set.

[0098] In practical implementation, the magnitudes of the elements in Formula 1 are not identical, and the direction formed by the real and imaginary parts of the complex number e can be any direction within a 360° range. In this embodiment, by summing the phase differences of each element in the phase difference set, it is equivalent to accumulating the frequency offset of each individual element. If the frequency offset value is correct, the sum will become a large value; conversely, if the frequency offset value is incorrect, the elements in Formula 1 will have irregular frequency offsets, resulting in a smaller sum. Based on this understanding, if the total phase difference s sum If the magnitude is greater than a preset threshold, the frequency offset value calculated in step S520 is determined as the final frequency offset value; otherwise, if the total phase difference s sum If the modulus is less than the preset threshold, then return to re-execute steps S300, S400 and S500 to redetermine the frequency offset value.

[0099] In this embodiment, the execution order between steps S520 and S530 is not restricted.

[0100] In an optional embodiment, between steps S600 and S700, the method further includes: establishing a wireless connection between the crystal-free Bluetooth chip and the host device in a state without a channel selection circuit. Please refer to... Figure 1 After the frequency offset compensation unit of the channel selection circuit 4 compensates for the frequency offset of the oscillator, a connection can be established with the host device. Then, the channel selection circuit 3 is connected by using the switching switch S to disconnect the channel selection circuit 4 and use the channel selection circuit 3 to transmit and receive data.

[0101] This embodiment also discloses a channel selection communication device for a crystal-free Bluetooth chip, used in a crystal-free Bluetooth chip with a channel selection circuit. The crystal-free Bluetooth chip integrates a data path without a channel selection circuit. Please refer to [reference needed]. Figure 4 , Figure 4 This is a schematic diagram of a channel selection communication device for a crystal-free Bluetooth chip disclosed in this embodiment. The channel selection communication device for a crystal-free Bluetooth chip includes: a channelless connection module 100, a host data packet transmission module 200, a first synchronization sequence module 300, a second synchronization sequence module 400, a frequency offset value determination module 500, a frequency offset compensation module 600, and a path switching module 700, wherein:

[0102] The channelless connection module 100 is used to connect the data path of the channelless selection circuit and disconnect the channel selection circuit when the crystal-free Bluetooth chip is powered on.

[0103] The host data packet transmission module 200 is used to transmit the host data packet received by the radio frequency unit to the channelless selection circuit, wherein the host data packet is a data packet wirelessly transmitted by an external host device;

[0104] The first synchronization sequence module 300 is used to generate a first synchronization sequence s based on the data frame synchronization header in the host data packet using a channelless selection circuit. l The first synchronization sequence s l This is a local sequence;

[0105] The second synchronization sequence module 400 is used to receive the second synchronization sequence s representing host data packets sent by the host device. r The second synchronization sequence s r This is the synchronization sequence of the host device at a standard frequency.

[0106] The frequency offset determination module 500 is used to determine the frequency offset value based on the first synchronization sequence s. l Second synchronization sequence s r Determine the frequency offset of the crystalless Bluetooth chip relative to the host device;

[0107] The frequency offset compensation module 600 is used to compensate the frequency offset of the oscillator in the crystalless Bluetooth chip according to the frequency offset value, so as to align the frequency of the crystalless Bluetooth chip with the frequency of the host device.

[0108] The path switching module 700 is used to switch the data path connected to the channel selection circuit so as to use the channel selection circuit to interact with the host device.

[0109] In an optional embodiment, the frequency offset determination module 500 includes:

[0110] The phase difference calculation unit is used to calculate the phase difference of the first synchronization sequence s. l With the second synchronization sequence s r Conjugate multiplication yields the first synchronization sequence s. l Second synchronization sequence s r The sum of phase differences at each sampling point;

[0111] The frequency offset calculation unit is used to calculate the frequency offset of the crystalless Bluetooth chip relative to the host device based on the phase difference set.

[0112] In an optional embodiment, the frequency offset calculation unit is specifically used for:

[0113] Select the phase difference of a target element from the set of phase differences as the target phase difference;

[0114] Calculate the frequency offset value at the corresponding frequency point based on the target phase difference;

[0115] The frequency offset value corresponding to the target phase difference is used as the frequency offset value of the crystalless Bluetooth chip relative to the host device.

[0116] In an optional embodiment, the target element is not the first sampling point;

[0117] The frequency offset calculation unit is specifically used to: subtract the target phase difference from the phase difference of the first sampling point to obtain the target phase difference after removing the initial phase;

[0118] The frequency offset of the crystalless Bluetooth chip relative to the host device is calculated based on the target phase difference after removing the initial phase.

[0119] In an optional embodiment, the frequency offset determination module 500 further includes:

[0120] The summation unit is used to sum the elements in the phase difference set to obtain the total phase difference s. sum ;

[0121] The summation judgment unit is used to determine the sum of phase differences s. sum If the magnitude of the sum of phase differences is greater than a preset threshold, then the frequency offset value calculated in module 520 is determined as the final frequency offset value. If the magnitude of the sum of phase differences is less than a preset threshold, then the first synchronization sequence module 300, the second synchronization sequence module 400, and the frequency offset value determination module 500 are re-executed.

[0122] In an optional embodiment, it further includes:

[0123] The connection establishment module is used to establish a wireless connection between the crystal-free Bluetooth chip and the host device in the absence of a channel selection circuit.

[0124] This embodiment also discloses a computer device, including: performing channel selection communication based on a crystal-free Bluetooth chip using the method disclosed in the above embodiments, or including the apparatus disclosed in the above embodiments.

[0125] This embodiment also discloses a crystal-free Bluetooth chip having an integrated circuit, which is designed to implement the methods disclosed in the above embodiments.

[0126] This embodiment also discloses a channel selection communication system without a crystal oscillator Bluetooth chip, which has an integrated circuit and includes: a host device and the crystal oscillator-free Bluetooth chip disclosed in the above embodiment, wherein the crystal oscillator-free Bluetooth chip interacts with the host device.

[0127] According to embodiments of the present invention, a channel selection communication method, apparatus, and system for a crystal-free Bluetooth chip are disclosed. The crystal-free Bluetooth chip, which includes a channel selection circuit, integrates a data path without a channel selection circuit. When the crystal-free Bluetooth chip is powered on, the data path of the channel selection circuit is connected, and the channel selection circuit is disconnected. The host data packet received by the radio frequency unit is transmitted to the channel selection circuit. The channel selection circuit generates a local first synchronization sequence based on the data frame synchronization header in the host data packet. A second synchronization sequence representing the host data packet sent by the host device is received; the second synchronization sequence is the synchronization sequence of the host device at a standard frequency. Based on this, the frequency offset value of the crystal-free Bluetooth chip relative to the host device is determined according to the first and second synchronization sequences, and frequency offset compensation is performed on the oscillator in the crystal-free Bluetooth chip to align the frequency of the crystal-free Bluetooth chip with the frequency of the host device. Finally, the data path connected to the channel selection circuit is switched to enable data interaction with the host device using the channel selection circuit. Because host data packets are received via a data path without a channel selection circuit before establishing a communication connection, the information in these packets is not filtered out by the channel selection circuit. This means the entire content of the data packet is covered, enabling frequency offset estimation of the local oscillator and frequency offset compensation for the oscillator in the crystalless Bluetooth chip. This ensures the frequency of the crystalless Bluetooth chip is aligned with the host device's frequency. Then, the data path connected to the channel selection circuit is switched. This ensures frequency alignment with the host device, guaranteeing normal data transmission and reception. Furthermore, because of the frequency alignment, data packets (target signals) sent by the host device will not be mistakenly filtered out due to frequency offset falling outside the target channel. Additionally, since data interaction with the host device utilizes the channel selection circuit, the effect of filtering out information outside the target channel is preserved, thus improving the quality of the received signal. In summary, for communication using a channel selection circuit, the probability of data loss due to target signal filtering is reduced.

[0128] In practical applications, a channel-selection-free path is added to the existing channel selection circuit to calculate and compensate for frequency offset, enabling the system to handle large frequency deviations. Furthermore, by setting thresholds to determine whether synchronization is successful and whether frequency offset compensation is accurate, the effectiveness of frequency offset compensation can be improved. For ease of understanding by those skilled in the art, please refer to... Figure 3 and Figure 5 , Figure 5This is a schematic diagram illustrating a data transmission and reception example without adding a channel selection path as disclosed in this embodiment. As described above, when transmitting and receiving data using a channel selection circuit, information outside the target channel can be filtered out, retaining only the target signal, thereby improving the quality of the received signal. However, its problem is that, for example... Figure 5 As shown, due to the frequency offset of the crystalless Bluetooth chip relative to the host device, if the frequency offset value f of the local oscillator... offset If the frequency offset is too large, the signal frequency will fall outside the target channel. That is, the target signal that should be in the channel (shown by the dashed ellipse) will fall outside the target channel (shown by the solid ellipse). In this case, the target signal outside the target channel (shown by the solid ellipse) will be incorrectly filtered out by the channel selection circuit, resulting in data loss and making it impossible to estimate the frequency offset of the oscillator.

[0129] In this embodiment, a channel-free path is added to the existing channel selection circuit. Since the channel-free path does not perform filtering operations, it can retain complete information, thus enabling the reception of data packets from the host device. Based on this, data synchronization, frequency offset calculation, and compensation are performed using the synchronization header in the data frame. After frequency offset compensation, a communication connection is established, and the system switches to the path with the channel selection circuit. This not only achieves frequency offset compensation but also leverages the advantages of the channel selection circuit to improve the quality of signal reception.

[0130] In addition, the present invention provides a computer-readable storage medium, such as a chip, an optical disc, etc., on which an executable program is stored, which, when executed, implements the method described in any of the above-mentioned embodiments.

[0131] It should be noted that the computer-readable storage medium described in the embodiments of this disclosure is not limited to the embodiments given above. For example, it can also be an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In the embodiments of this disclosure, the computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0132] It will be understood by those skilled in the art that the above-described preferred solutions can be freely combined and superimposed without conflict. The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings; for example, two consecutively indicated blocks may actually be executed substantially in parallel, or sometimes in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions. The numbering of each step in this document is for ease of explanation and reference only and is not intended to limit the order of execution. The specific execution order is determined by the technology itself, and those skilled in the art can determine various permissible and reasonable orders based on the technology itself.

[0133] It should be noted that the use of step numbers (letters or numbers) to refer to certain specific method steps in this invention is merely for the purpose of convenience and brevity in description, and is by no means intended to restrict the order of these method steps. Those skilled in the art will understand that the order of the relevant method steps should be determined by the technology itself and should not be unduly restricted by the existence of step numbers. Those skilled in the art can determine various permissible and reasonable orderings of steps based on the technology itself.

[0134] Those skilled in the art will understand that, without conflict, the above-mentioned preferred solutions can be freely combined and superimposed.

[0135] It should be understood that the above embodiments are merely exemplary and not restrictive. Various obvious or equivalent modifications or substitutions that can be made by those skilled in the art regarding the above details without departing from the basic principles of the present invention will be included within the scope of the claims of the present invention.

Claims

1. A channel selection communication method of a crystal-less Bluetooth chip, for a crystal-less Bluetooth chip having a channel selection circuit, characterized by, The data path of the channel selection circuit-free Bluetooth chip is integrated with a channel selection circuit-free data path, and the method comprises the following steps: Step S100, when the channel selection circuit-free Bluetooth chip is powered on, the channel selection circuit-free data path is connected, and the channel selection circuit is disconnected; Step S200, a host data packet received by a radio frequency unit is transmitted to the channel selection circuit-free data path, wherein the host data packet is a data packet wirelessly transmitted by an external host device; Step S300, generating a first synchronization sequence (s l ) according to a data frame synchronization head in the host data packet by using the channel selection-free circuit, the first synchronization sequence (s l ) being a local sequence; Step S400, receiving a second synchronization sequence (s r ) representing the host data packet sent by the host device, the second synchronization sequence (s r ) being a synchronization sequence at a standard frequency of the host device; Step S500, determining a frequency offset value of the Bluetooth chip without crystal oscillator relative to the host device according to the first synchronization sequence (s l ) and the second synchronization sequence (s r ). Step S600, frequency offset compensation is performed on an oscillator in the channel selection circuit-free Bluetooth chip according to the frequency offset value, so that the frequency of the channel selection circuit-free Bluetooth chip is aligned with the frequency of the host device; Step S700, the data path connected to the channel selection circuit is switched to utilize the channel selection circuit to interact with the host device.

2. The channel selection communication method of a Bluetooth chip without a crystal oscillator according to claim 1, wherein, The step S500 comprises: Step S510, conjugate multiplication of the first synchronization sequence (s l ) and the second synchronization sequence (s r ), to obtain the phase difference set of each sampling point of the first synchronization sequence (s l ) and the second synchronization sequence (s r ); Step S520, the frequency offset value of the channel selection circuit-free Bluetooth chip relative to the host device is calculated according to the phase difference set.

3. The channel selection communication method of a Bluetooth chip without a crystal oscillator according to claim 2, wherein The step S520 comprises: Step S521, a phase difference of a target element is selected from the phase difference set as a target phase difference; Step S522, the frequency offset value of the corresponding frequency point is calculated according to the target phase difference; Step S523, the frequency offset value corresponding to the target phase difference is taken as the frequency offset value of the channel selection circuit-free Bluetooth chip relative to the host device.

4. The channel selection communication method of a Bluetooth chip without a crystal oscillator according to claim 3, wherein, In the step S521, the target element is not the first sampling point; Between the step S521 and the step S522, the following steps are further included: Step S511, the target phase difference is subtracted from the phase difference of the first sampling point to obtain a target phase difference after removing the initial phase; In the step S522, the frequency offset value of the channel selection circuit-free Bluetooth chip relative to the host device is calculated according to the target phase difference after removing the initial phase.

5. The channel selection communication method of a Bluetooth chip without a crystal oscillator according to any one of claims 2 to 4, wherein The step S500 further comprises: Step S530, summing each element in the phase difference set to obtain a phase difference sum (s sum ); Step S540, judging whether the modulus of the phase difference sum (s sum ) is greater than a preset threshold value; if greater than the preset threshold value, determining the frequency offset value calculated in the step S520 as a final frequency offset value; if the modulus of the phase difference sum is less than the preset threshold value, returning to re-execute the step S300, the step S400 and the step S500.

6. The channel selection communication method of a Bluetooth chip without a crystal oscillator according to claim 1, wherein, Between the step S600 and the step S700, the following steps are further included: Wireless connection between the channel selection circuit-free Bluetooth chip and the host device is established in the state of the channel selection circuit-free state.

7. A channel selection communication device of a crystal-less Bluetooth chip, for a crystal-less Bluetooth chip with a channel selection circuit, characterized in that, The data path of the channel selection circuit-free Bluetooth chip is integrated with a channel selection circuit-free data path, and the device comprises: A channel selection circuit-free connection module (100) is configured to connect the channel selection circuit-free data path and disconnect the channel selection circuit when the channel selection circuit-free Bluetooth chip is powered on; A host data packet transmission module (200) is configured to transmit a host data packet received by a radio frequency unit to the channel selection circuit-free data path, wherein the host data packet is a data packet wirelessly transmitted by an external host device; a first synchronization sequence module (300) for generating a first synchronization sequence (s l ) according to a data frame synchronization header in the host data packet by using the channel selection free circuit, the first synchronization sequence (s l ) being a local sequence; a second synchronization sequence module (400) configured to receive a second synchronization sequence (s r ) indicative of the host data packet transmitted by the host device, the second synchronization sequence (s r ) being a synchronization sequence at a standard frequency of the host device; a frequency offset value determination module (500) configured to determine a frequency offset value of the Bluetooth chip without crystal oscillator relative to the host device according to the first synchronization sequence (s l ) and the second synchronization sequence (s r ). A frequency offset compensation module (600) is configured to perform frequency offset compensation on an oscillator in the channel selection circuit-free Bluetooth chip according to the frequency offset value, so that the frequency of the channel selection circuit-free Bluetooth chip is aligned with the frequency of the host device; A path switching module (700) is configured to switch the data path connected to the channel selection circuit to utilize the channel selection circuit to interact with the host device.

8. The channel selection communication apparatus of claim 7, wherein the reference clock signal is generated by a clock generator. The frequency offset value determination module (500) comprises: a phase difference calculation unit configured to calculate phase differences between the first synchronization sequence (s l ) and the second synchronization sequence (s r ) by conjugate multiplication, to obtain a set of phase differences of each sample point of the first synchronization sequence (s l ) and the second synchronization sequence (s r ). A frequency offset value calculation unit is configured to calculate the frequency offset value of the channel selection circuit-free Bluetooth chip relative to the host device according to the phase difference set.

9. The channel selection communication apparatus of claim 8, wherein the reference clock signal is generated by a clock generator. The frequency offset value calculation unit is specifically configured to: select a target phase difference from the set of phase differences as a target phase difference; calculate a frequency offset value of a corresponding frequency point according to the target phase difference; take the frequency offset value corresponding to the target phase difference as the frequency offset value of the Bluetooth chip without a crystal oscillator relative to the host device.

10. The channel selection communication apparatus without crystal oscillator Bluetooth chip according to claim 3, wherein, The target element is not the first sampling point. The frequency offset value calculation unit is specifically configured to: subtract the target phase difference from the phase difference of the first sampling point to obtain a target phase difference after removing an initial phase; calculate the frequency offset value of the Bluetooth chip without a crystal oscillator relative to the host device according to the target phase difference after removing the initial phase.

11. The channel selection communication apparatus of claim 8-10, wherein the channel selection communication apparatus is a Bluetooth chip without a crystal oscillator. The frequency offset value determination module (500) further includes: a summation unit for summing the elements of the set of phase differences to obtain a sum of phase differences (s sum ). a sum judging unit for judging whether a modulus value of the phase difference sum (s sum ) is greater than a preset threshold value; if greater than the preset threshold value, determining the frequency offset value calculated in the module (520) as a final frequency offset value; if the modulus value of the phase difference sum is less than the preset threshold value, returning to re-execute the first synchronization sequence module (300), the second synchronization sequence module (400) and the frequency offset value determining module (500).

12. The channel selection communication apparatus without crystal oscillator Bluetooth chip according to claim 7, wherein, Further comprising: The connection establishment module is configured to establish a wireless connection between the Bluetooth chip without a crystal oscillator and the host device in a state without a channel selection circuit.

13. A computer device, comprising: Including: The method according to any one of claims 1-6 is used for channel selection communication based on the Bluetooth chip without a crystal oscillator, or the device according to any one of claims 7-12.

14. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program stored in the storage medium is used for being executed by the processor to realize the method according to any one of claims 1-6.

15. A crystal-free Bluetooth chip, having an integrated circuit thereon, characterized in that, The integrated circuit is designed to realize the method according to any one of claims 1-6.

16. A channel selection communication system of a Bluetooth chip without a crystal oscillator, having an integrated circuit thereon, characterized by Including: The host device; The Bluetooth chip without a crystal oscillator according to claim 15 interacts with the host device for data interaction.

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