Crystal-less bluetooth chip frequency offset compensation method, device and system based on cbpf

Abstract

The application discloses a crystal oscillator-free Bluetooth chip frequency deviation compensation method, device and system based on CBPF, wherein the method comprises the following steps: sequentially providing a first sine wave signal sequence to a complex band-pass filter; adjusting the center frequency of the complex band-pass filter according to a plurality of first output waveforms, so that the adjusted center frequency is equal to a target frequency; using an LC oscillator in a crystal oscillator-free Bluetooth chip as a clock source to generate a series of second sine wave signal sequences with different frequencies; sequentially providing the second sine wave signal sequences to the complex band-pass filter; and determining the frequency deviation value of the crystal oscillator-free Bluetooth chip according to the frequency deviation of a plurality of second output waveforms relative to the adjusted center frequency, so as to compensate the LC oscillator according to the frequency deviation value. Thus, the frequency deviation compensation of the crystal oscillator-free Bluetooth chip is realized.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and specifically to a method, apparatus, and system for frequency offset compensation of a crystal-free Bluetooth chip based on CBPF. Background Technology

[0002] In the field of wireless communication, the performance of the oscillator is crucial to the communication system. First, the oscillator needs to provide a stable and accurate clock signal to ensure precise synchronization of the various 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, it needs to maintain low phase noise to ensure the quality of signal transmission. Thus, wireless communication SoC chips require oscillators that are stable, accurate, and have 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, a significant difference exists between the frequency of the internal oscillator and the standard frequency, i.e., frequency deviation, which causes the system to malfunction.

[0006] Therefore, how to compensate for frequency offset in crystal-free Bluetooth chips 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 method, apparatus, and system for frequency offset compensation of crystal-free Bluetooth chips based on CBPF, so as to perform frequency offset compensation for crystal-free Bluetooth chips.

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

[0009] In a first aspect, embodiments of the present invention disclose a frequency offset compensation method for a crystal-free Bluetooth chip based on CBPF, comprising:

[0010] Step S100: Using an external precision clock as a clock source, a series of first sine wave signal sequences with different frequencies are generated;

[0011] Step S200: The first sine wave signal sequence is sequentially provided to the complex bandpass filter, wherein the center frequency of the complex bandpass filter is adjustable;

[0012] Step S300: Obtain several first output waveforms of the complex bandpass filter;

[0013] Step S400: Adjust the center frequency of the complex bandpass filter according to several first output waveforms so that the adjusted center frequency is equal to the target frequency;

[0014] Step S500: Use the internal LC oscillator of the crystalless Bluetooth chip as a clock source to generate a series of second sine wave signal sequences with different frequencies;

[0015] Step S600: The second sine wave signal sequence is sequentially provided to the complex bandpass filter;

[0016] Step S700: Obtain several second output waveforms of the complex bandpass filter;

[0017] Step S800: Determine the frequency offset value of the crystalless Bluetooth chip based on the frequency offset of several second output waveforms relative to the adjusted center frequency, so as to compensate the LC oscillator according to the frequency offset value.

[0018] Optionally, in step S100, the intensity of each sinusoidal signal in the first sinusoidal signal sequence is the same;

[0019] In step S400, the frequency corresponding to the first output waveform with the strongest signal strength among several first output waveforms is taken as the center frequency.

[0020] Optionally, step S400 includes:

[0021] Step S410: Determine whether the center frequency is equal to the target frequency; if the center frequency is equal to the target frequency, proceed to step S420; if the center frequency is not equal to the target frequency, proceed to step S430.

[0022] Step S420: Use the current center frequency as the adjusted center frequency;

[0023] Step S430: After adjusting the current center frequency, repeat steps S100, S200, S300 and S410 until the center frequency equals the target frequency.

[0024] Optionally, in step S500, the frequency range of the second sine wave signal sequence covers the frequency offset range of the LC oscillator.

[0025] Optionally, step S800 includes:

[0026] Step S810: Measure the signal strength of several second output waveforms;

[0027] Step S820: The frequency corresponding to the second output waveform with the strongest signal strength is taken as the single-pass signal frequency;

[0028] Step S830: Difference between the single-pass signal frequency and the target frequency to obtain the frequency offset value of the crystal-free Bluetooth chip.

[0029] Optionally, it also includes:

[0030] A switching switch is used to switch between the external precision clock and the phase-locked loop (PLL) unit, or to switch between the internal LC oscillator and the PLL unit, so that the PLL unit can provide a first sine wave signal sequence or a second sine wave signal sequence to the complex bandpass filter, respectively.

[0031] Secondly, embodiments of the present invention disclose a frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF, comprising:

[0032] The first sine wave generation module is used to generate a series of first sine wave signal sequences with different frequencies using an external precision clock as a clock source.

[0033] The first sine wave providing module is used to sequentially provide the first sine wave signal sequence to the complex bandpass filter, wherein the center frequency of the complex bandpass filter is adjustable;

[0034] The first waveform acquisition module is used to acquire several first output waveforms of the complex bandpass filter;

[0035] The center frequency adjustment module is used to adjust the center frequency of the complex bandpass filter based on several first output waveforms, so that the adjusted center frequency is equal to the target frequency.

[0036] The second sine wave generation module is used to generate a series of second sine wave signal sequences with different frequencies by using the internal LC oscillator of the crystalless Bluetooth chip as a clock source.

[0037] The second sine wave providing module is used to sequentially provide the second sine wave signal sequence to the complex bandpass filter;

[0038] The second waveform acquisition module is used to acquire several second output waveforms of the complex bandpass filter;

[0039] The frequency offset determination module is used to determine the frequency offset value of the crystalless Bluetooth chip based on the frequency offset of several second output waveforms relative to the adjusted center frequency, so as to compensate the LC oscillator according to the frequency offset value.

[0040] Optionally, in the first sine wave generation module, the intensity of each sine wave signal in the first sine wave signal sequence is the same;

[0041] In the center frequency adjustment module, the frequency corresponding to the first output waveform with the strongest signal strength among several first output waveforms is taken as the center frequency.

[0042] Optionally, the center frequency adjustment module includes:

[0043] The judgment unit is used to determine whether the center frequency is equal to the target frequency; if the center frequency is equal to the target frequency, the frequency determination unit is executed; if the center frequency is not equal to the target frequency, the frequency adjustment unit is executed.

[0044] The frequency determination unit is used to take the current center frequency as the adjusted center frequency.

[0045] The frequency adjustment unit is used to repeatedly execute the first sine wave generation module, the first sine wave provision module, the first waveform acquisition module, and the judgment unit after adjusting the current center frequency, until the center frequency equals the target frequency.

[0046] Optionally, in the second sine wave generation module, the frequency range of the second sine wave signal sequence covers the frequency offset range of the LC oscillator.

[0047] Optionally, the frequency offset determination module is specifically used for:

[0048] Measure the signal strength of several second output waveforms;

[0049] The frequency corresponding to the second output waveform with the strongest signal strength is taken as the single-pass signal frequency.

[0050] The frequency offset of the crystalless Bluetooth chip is obtained by subtracting the frequency of the single-pass signal from the target frequency.

[0051] Optionally, it also includes:

[0052] The switching module is used to switch between the external precision clock and the phase-locked loop (PLL) unit, or the internal LC oscillator and the PLL unit, so as to provide a first sine wave signal sequence or a second sine wave signal sequence to the complex bandpass filter using the PLL unit, respectively.

[0053] Thirdly, embodiments of the present invention disclose a computer device, comprising:

[0054] Frequency offset compensation for a crystal-free Bluetooth chip based on CBPF can be performed using the method disclosed in the first aspect above, or the apparatus disclosed in the second aspect above can be used.

[0055] Fourthly, embodiments of the present invention disclose 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 disclosed in the first aspect above.

[0056] Fifthly, embodiments of the present invention disclose a crystal-free Bluetooth chip having an integrated circuit, the integrated circuit being designed to implement the method disclosed in the first aspect above.

[0057] Beneficial effects:

[0058] According to an embodiment of the present invention, a method, apparatus, and system for frequency offset compensation of a crystal-free Bluetooth chip based on a CBPF are disclosed. In the first time period, an external precision clock is used as a clock source to generate a series of first sine wave signal sequences with different frequencies, which are then sequentially provided to a complex bandpass filter. This allows the center frequency of the bandpass filter to be determined. Based on this, the center frequency of the complex bandpass filter is adjusted to be equal to the target frequency. Then, in the second time period, an internal LC oscillator of the crystal-free Bluetooth chip is used as a clock source to generate a series of second sine wave signal sequences with different frequencies, which are then sequentially provided to the complex bandpass filter. The frequency offset of the second output waveform relative to the adjusted center frequency is the frequency offset value of the crystal-free Bluetooth chip. Therefore, the LC oscillator can be compensated based on this frequency offset value, thus realizing the frequency offset compensation of the crystal-free Bluetooth chip.

[0059] 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

[0060] The embodiments of the present invention will now be described with reference to the accompanying drawings. In the drawings:

[0061] Figure 1 This is a flowchart of a frequency offset compensation method for a crystal-free Bluetooth chip based on CBPF disclosed in this embodiment;

[0062] Figure 2 This embodiment discloses a block diagram of the frequency offset compensation principle of a crystal-free Bluetooth chip based on CBPF.

[0063] Figure 3The center frequency F of the complex bandpass filter CBPF disclosed in this embodiment is adjusted. c A state diagram;

[0064] Figure 4 The center frequency F of the complex bandpass filter CBPF disclosed in this embodiment is adjusted. c Another state diagram;

[0065] Figure 5 This is another principle block diagram of frequency offset compensation for a crystal-free Bluetooth chip based on CBPF disclosed in this embodiment;

[0066] Figure 6 This is a schematic diagram of a frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF disclosed in this embodiment. Detailed Implementation

[0067] 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.

[0068] 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.

[0069] 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."

[0070] 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.

[0071] To compensate for frequency offset in crystal-free Bluetooth chips, this embodiment discloses a method for frequency offset compensation in crystal-free Bluetooth chips based on CBPF. Please refer to [link / reference]. Figure 1 , Figure 1 This embodiment discloses a frequency offset compensation method for a crystal-free Bluetooth chip based on CBPF. The method includes steps S100, S200, S300, S400, S500, S600, S700, and S800, wherein:

[0072] Step S100: Using an external precision clock as the clock source, a series of first sine wave signal sequences with different frequencies are generated. Please refer to... Figure 2 , Figure 2 This embodiment discloses a block diagram of a frequency offset compensation principle for a crystal-free Bluetooth chip based on a CBPF. An external clock calibration unit 1 is connected to a PLL unit 2 within the crystal-free Bluetooth chip, providing a precise clock for the chip. In this embodiment, before the crystal-free Bluetooth chip leaves the factory, the external clock calibration unit 1 is connected to the chip to generate a series of first sine wave signal sequences with different frequencies. These first sine wave signal sequences are then used to calibrate the CBPF unit 3 within the crystal-free Bluetooth chip. In this embodiment, the CBPF unit 3 refers to a Complex Band Pass Filter (CBPF). The characteristic of the CBPF unit is that its center frequency is adjustable; specifically, the pass frequency of the CBPF unit can be changed by adjusting the capacitor and voltage.

[0073] Step S200: The first sinusoidal signal sequence is sequentially provided to the complex bandpass filter CBPF. As discussed above, the center frequency F of the complex bandpass filter CBPF is... c The size is adjustable; at the center frequency F c Nearby signals can pass through a complex bandpass filter CBPF, while at the center frequency F c Signals outside the vicinity will be filtered out by a complex bandpass filter (CBPF). In this embodiment, the first sinusoidal signal sequence is sequentially provided to the complex bandpass filter (CBPF), thereby allowing the CBPF to filter out signals at the center frequency F. c Nearby signals.

[0074] Step S300: Obtain several first output waveforms of the complex bandpass filter CBPF. Specifically, since the complex bandpass filter CBPF has a center frequency F... c Therefore, when the first sinusoidal signal sequence is sequentially provided to the complex bandpass filter CBPF, at the center frequency F c Nearby signals can pass through a complex bandpass filter CBPF, while at the center frequency F c Frequencies other than those specified will be filtered out. Of course, when the frequency of the first sine wave signal crosses the center frequency F... c When the boundary is reached, part of the first sine wave signal will pass through and part will be filtered out.

[0075] Step S400: Adjust the center frequency F of the complex bandpass filter CBPF based on several first output waveforms. c In this embodiment, the center frequency F of the CBPF is adjusted. c This makes the adjusted center frequency Fc It equals the target frequency F. For details, please refer to [reference needed]. Figure 3 and Figure 4 , Figure 3 The center frequency F of the complex bandpass filter CBPF disclosed in this embodiment is adjusted. c A state diagram, Figure 4 The center frequency F of the complex bandpass filter CBPF disclosed in this embodiment is adjusted. c Another state diagram, Figure 3 and Figure 4 In the diagram, the solid black arched lines represent signals of different frequencies input to the CBPF, the dashed black arched lines represent the bandpass range of the complex bandpass filter CBPF, and F is the target frequency. c This is the center frequency of the CBPF. Figure 3 In the example state, after signals of different frequencies are input to the complex bandpass filter CBPF, only the frequency equal to the center frequency F of the CBPF is filtered out. c When a signal passes through, the center frequency F of the CBPF can be determined by measuring the frequency of the passing signal. c And F c >F, at this point, the pass frequency of the CBPF cell, that is, the center frequency F, can be changed by adjusting the capacitor and voltage. c This makes the center frequency F c Approaching the target frequency F; such as Figure 4 As shown, the black arched dashed line is adjusted to cover the target frequency F, so that the signal frequency passing through the complex bandpass filter CBPF is equal to the target frequency F.

[0076] In the specific implementation process, the center frequency F of the CBPF is... c When adjusted to equal the target frequency F, the center frequency F can be fixed. c .

[0077] In an optional embodiment, in step S100, the intensity of each sinusoidal signal in the first sinusoidal signal sequence is the same; in step S400, the frequency corresponding to the first output waveform with the strongest signal intensity among the plurality of first output waveforms is taken as the center frequency F. c As described above, at the center frequency F c Nearby signals can pass through a complex bandpass filter (CBPF), at which point the signal strength is strongest; at the center frequency F... c Frequencies other than those specified will be filtered out, at which point the signal strength is weakest; when the frequency of the first sine wave signal crosses the center frequency F... cWhen the signal reaches the boundary, part of the first sine wave signal will pass through and part will be filtered out, at which point the signal strength is in the middle. Since all the sine wave signals in the first sine wave signal sequence have the same strength, by detecting the signal strength of the first output waveform, the signal with the strongest signal strength can be determined, and the frequency corresponding to this signal is the center frequency F. c In a specific embodiment, please refer to... Figure 2 The signal strength can be calculated using the power calculation unit 5.

[0078] Step S500: Using the internal LC oscillator of the crystalless Bluetooth chip as a clock source, a series of second sine wave signal sequences with different frequencies are generated. Specifically, the center frequency F of the CBPF is fixed. c Then, proceed to the second stage. Please refer to [the relevant documentation]. Figure 2 and Figure 5 , Figure 5 This embodiment presents another principle block diagram for frequency offset compensation of a crystal-free Bluetooth chip based on CBPF. In the second stage, a switch is used to switch the clock source to the internal LC oscillator 4 of the crystal-free Bluetooth chip. In this embodiment, the LC oscillator 4 is used to generate an internal reference clock. Compared to an external crystal oscillator, the reference clock generated by the LC oscillator 4 deviates from the standard clock, i.e., there is a frequency offset. To compensate for the frequency offset, in this embodiment, the internal LC oscillator 4 generates a series of second sine wave signal sequences with different frequencies. The frequency offset value of the LC oscillator 4 can be determined based on the frequency of the second sine wave signal passing through the CBPF unit 3.

[0079] In an optional embodiment, to cover the frequency offset range of the LC oscillator, in step S500, the frequency range of the second sine wave signal sequence covers the frequency offset range of the LC oscillator. This configuration ensures that even if the signal experiences frequency offset, it remains within the frequency range of the second sine wave signal sequence, thus covering signals with all frequency offsets.

[0080] Step S600: The second sinusoidal signal sequence is sequentially provided to the complex bandpass filter CBPF. As discussed above, at the center frequency F... c Nearby signals can pass through a complex bandpass filter CBPF, while at the center frequency F c Signals outside the vicinity will be filtered out by a complex bandpass filter (CBPF). In this embodiment, the second sine wave signal sequence is sequentially provided to the complex bandpass filter (CBPF), thereby allowing the CBPF to filter out signals at the center frequency F. c Nearby signals.

[0081] Step S700: Acquire several second output waveforms of the complex bandpass filter CBPF. In this embodiment, the center frequency F of the complex bandpass filter CBPF is adjusted in the first stage. c The adjusted center frequency F c It equals the target frequency F. Please refer to [reference needed]. Figure 4 The signal frequency passing through the complex bandpass filter CBPF is equal to the target frequency F, which is also the adjusted center frequency F. c .

[0082] Step S800, based on several second output waveforms relative to the adjusted center frequency F c The frequency offset is determined to be the frequency offset value of the crystalless Bluetooth chip, in order to compensate the LC oscillator 4 according to the frequency offset value. Specifically, since only when the frequency is equal to the center frequency F of the CBPF... c Since the signal passes through the complex bandpass filter CBPF, the strongest single-pass signal can be determined by measuring its signal strength. The frequency offset F of the internal LC oscillator 4 can be obtained by subtracting the frequency F' corresponding to the strongest single-pass signal from the target frequency F. offset .

[0083] In a specific embodiment, step S800 includes: step S810, measuring the signal strength of several second output waveforms; step S820, taking the frequency corresponding to the second output waveform with the strongest signal strength as the single-pass signal frequency F'; and step S830, subtracting the single-pass signal frequency F' from the target frequency F to obtain the frequency offset value F of the crystal-free Bluetooth chip. offset For details, please refer to... Figure 5 The signal strength can be calculated using the power calculation unit 5.

[0084] In order to make the center frequency F c Adjusting to a frequency equal to the target frequency F, in an optional embodiment, step S400 includes:

[0085] Step S410, determine the center frequency F c Is it equal to the target frequency F? If the center frequency F c If the center frequency is equal to the target frequency F, then proceed to step S420; if the center frequency F... c If it is not equal to the target frequency F, then proceed to step S430;

[0086] Step S420, set the current center frequency F c The adjusted center frequency F c ;

[0087] Step S430, after adjusting the current center frequency F cThen, steps S100, S200, S300, and S410 are repeated until the center frequency F is reached. c It equals the target frequency F.

[0088] Specifically, when the center frequency F c When the center frequency of the CBPF equals the target frequency F, it indicates that the center frequency of the CBPF has been adjusted to the desired target frequency F. At this point, the adjustment of the CBPF center frequency can be stopped, and the current center frequency F can be set to the target frequency F. c Fixed as the adjusted center frequency F c When the center frequency F c If the center frequency of the CBPF is not equal to the target frequency F, it indicates that the center frequency of the CBPF has not been adjusted to the desired target frequency F. At this time, the center frequency of the CBPF can be adjusted by capacitors and voltage. After adjusting the center frequency, repeat steps S100, S200, S300 and S410 according to the adjusted center frequency.

[0089] To achieve the two-stage switching, in an optional embodiment, the method further includes: using a switching switch to switch the external precision clock and the phase-locked loop (PLL) unit on, or to switch the internal LC oscillator and the PLL unit on, so as to provide a first sine wave signal sequence or a second sine wave signal sequence to the complex bandpass filter (CBPF) using the PLL unit, respectively. Please refer to [reference needed]. Figure 2 and Figure 5 When the switch switches the external clock calibration unit 1 and PLL unit 2 to conduct, the external clock calibration unit 1 generates a series of first sine wave signal sequences with different frequencies, which are input to the CBPF unit 3. The first sine wave signal sequences are then used to calibrate the CBPF unit 3 in the crystalless Bluetooth chip. When the switch switches the LC oscillator 4 and PLL unit 2 to conduct, the LC oscillator 4 generates a series of second sine wave signal sequences with different frequencies, which are input to the CBPF unit 3. The second sine wave signal sequences are then used to determine the frequency offset value of the LC oscillator 4.

[0090] This embodiment also discloses a frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF. Please refer to [link / reference]. Figure 6 , Figure 6 This is a schematic diagram of a frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF disclosed in this embodiment. The frequency offset compensation device includes: a first sine wave generation module 100, a first sine wave providing module 200, a first waveform acquisition module 300, a center frequency adjustment module 400, a second sine wave generation module 500, a second sine wave providing module 600, a second waveform acquisition module 700, and a frequency offset value determination module 800, wherein:

[0091] The first sine wave generation module 100 is used to generate a series of first sine wave signal sequences with different frequencies using an external precision clock as a clock source; the first sine wave supply module 200 is used to sequentially supply the first sine wave signal sequences to the complex bandpass filter CBPF, wherein the center frequency F of the complex bandpass filter CBPF is... c The size is adjustable; the first waveform acquisition module 300 is used to acquire several first output waveforms of the complex bandpass filter CBPF; the center frequency adjustment module 400 is used to adjust the center frequency F of the complex bandpass filter CBPF according to the several first output waveforms. c So that the adjusted center frequency F c The second sine wave generation module 500 uses the internal LC oscillator of the crystalless Bluetooth chip as a clock source to generate a series of second sine wave signal sequences with different frequencies; the second sine wave providing module 600 provides the second sine wave signal sequences to the complex bandpass filter CBPF in sequence; the second waveform acquisition module 700 acquires several second output waveforms of the complex bandpass filter CBPF; the frequency offset determination module 800 determines the frequency offset based on the several second output waveforms relative to the adjusted center frequency F. c The frequency offset is determined to determine the frequency offset value of the crystalless Bluetooth chip, so as to compensate the LC oscillator according to the frequency offset value.

[0092] In an optional embodiment, in the first sine wave generation module 100, the intensity of each sine wave signal in the first sine wave signal sequence is the same.

[0093] In the center frequency adjustment module 400, the frequency corresponding to the first output waveform with the strongest signal strength among several first output waveforms is taken as the center frequency F. c .

[0094] In an optional embodiment, the center frequency adjustment module 400 includes:

[0095] The judgment unit is used to determine the center frequency F. c Is it equal to the target frequency F? If the center frequency F c If the center frequency is equal to the target frequency F, then the frequency determination unit is executed; if the center frequency F is equal to the target frequency F, then the frequency determination unit is executed. c If the frequency is not equal to the target frequency F, then the frequency adjustment unit is executed;

[0096] The frequency determination unit is used to determine the current center frequency F. c The adjusted center frequency F c ;

[0097] The frequency adjustment unit is used to adjust the current center frequency F. cThen, the first sine wave generation module 100, the first sine wave providing module 200, the first waveform acquisition module 300, and the judgment unit are repeatedly executed until the center frequency F is reached. c It equals the target frequency F.

[0098] In an optional embodiment, in the second sine wave generation module 500, the frequency range of the second sine wave signal sequence covers the frequency offset range of the LC oscillator.

[0099] In an optional embodiment, the frequency offset value determination module 800 is specifically used for:

[0100] Measure the signal strength of several second output waveforms;

[0101] The frequency corresponding to the second output waveform with the strongest signal strength is taken as the single-pass signal frequency F'.

[0102] The frequency offset F of the crystal-free Bluetooth chip is obtained by subtracting the single-pass signal frequency F' from the target frequency F. offset .

[0103] In an optional embodiment, it further includes:

[0104] The switching module is used to switch between the external precision clock and the phase-locked loop (PLL) unit, or the internal LC oscillator and the PLL unit, so as to provide a first sine wave signal sequence or a second sine wave signal sequence to the complex bandpass filter (CBPF) using the PLL unit, respectively.

[0105] This embodiment also discloses a computer device, including:

[0106] Frequency offset compensation for crystal-free Bluetooth chips based on CBPF can be performed using the methods disclosed in the above embodiments, or the apparatus disclosed in the above embodiments can be used.

[0107] 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.

[0108] According to an embodiment of the present invention, a method, apparatus, and system for frequency offset compensation of a crystal-free Bluetooth chip based on a CBPF are disclosed. In the first time period, an external precision clock is used as a clock source to generate a series of first sine wave signal sequences with different frequencies, which are then sequentially provided to a complex bandpass filter. This allows the center frequency of the bandpass filter to be determined. Based on this, the center frequency of the complex bandpass filter is adjusted to be equal to the target frequency. Then, in the second time period, an internal LC oscillator of the crystal-free Bluetooth chip is used as a clock source to generate a series of second sine wave signal sequences with different frequencies, which are then sequentially provided to the complex bandpass filter. The frequency offset of the second output waveform relative to the adjusted center frequency is the frequency offset value of the crystal-free Bluetooth chip. Therefore, the LC oscillator can be compensated based on this frequency offset value, thus realizing the frequency offset compensation of the crystal-free Bluetooth chip.

[0109] In practical applications, the calibrated CBPF is used to evaluate the frequency offset of the chip's internal oscillator. Furthermore, the center frequency of the CBPF is less affected by the environment, allowing for accurate estimation of the internal oscillator's frequency offset even with significant changes in environmental conditions (temperature, voltage, etc.). This technology enables the establishment of communication connections without a crystal oscillator, thereby reducing product development difficulty, costs, and timelines, and allowing for more miniaturized devices.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] 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.

[0114] Those skilled in the art will understand that, without conflict, the above-mentioned preferred solutions can be freely combined and superimposed.

[0115] 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 frequency offset compensation method for a crystal-free Bluetooth chip based on CBPF, characterized in that, include: Step S100: Using an external precision clock as a clock source, a series of first sine wave signal sequences with different frequencies are generated; Step S200: The first sinusoidal signal sequence is sequentially provided to a complex bandpass filter (CBPF), wherein the center frequency (F) of the complex bandpass filter (CBPF) is... c Size adjustable; Step S300: Obtain several first output waveforms of the complex bandpass filter (CBPF); Step S400: Adjust the center frequency (F) of the complex bandpass filter (CBPF) according to the plurality of first output waveforms. c ), so that the adjusted center frequency (F) c The frequency (F) is equal to the target frequency. Step S500: Use the internal LC oscillator of the crystalless Bluetooth chip as a clock source to generate a series of second sine wave signal sequences with different frequencies; Step S600: The second sinusoidal signal sequence is sequentially provided to a complex bandpass filter (CBPF); Step S700: Obtain several second output waveforms of the complex bandpass filter (CBPF); Step S800, based on the plurality of second output waveforms relative to the adjusted center frequency (F c The frequency offset is used to determine the frequency offset value of the crystalless Bluetooth chip, so as to compensate the LC oscillator according to the frequency offset value.

2. The frequency offset compensation method for crystal-free Bluetooth chips based on CBPF as described in claim 1, characterized in that, In step S100, the intensity of each sinusoidal signal in the first sinusoidal signal sequence is the same; In step S400, the frequency corresponding to the first output waveform with the strongest signal strength among the plurality of first output waveforms is taken as the center frequency (F). c ).

3. The frequency offset compensation method for crystal-free Bluetooth chips based on CBPF as described in claim 2, characterized in that, Step S400 includes: Step S410, determine the center frequency (F) c Is the center frequency (F) equal to the target frequency (F)? c If the center frequency (F) equals the target frequency (F), then proceed to step S420; if the center frequency (F) c If the frequency (F) is not equal to the target frequency (F), then proceed to step S430. Step S420, the current center frequency (F) c ) as the adjusted center frequency (F c ); Step S430, after adjusting the current center frequency (F) c After that, steps S100, S200, S300, and S410 are repeated until the center frequency (F) is reached. c ) equals the target frequency (F).

4. The frequency offset compensation method for a crystal-free Bluetooth chip based on CBPF as described in any one of claims 1-3, characterized in that, In step S500, the frequency range of the second sine wave signal sequence covers the frequency offset range of the LC oscillator.

5. The frequency offset compensation method for a crystal-free Bluetooth chip based on CBPF as described in any one of claims 1-3, characterized in that, Step S800 includes: Step S810: Measure the signal strength of the plurality of second output waveforms; Step S820: The frequency corresponding to the second output waveform with the strongest signal strength is taken as the single-pass signal frequency (F'); Step S830: Subtract the single-pass signal frequency (F') from the target frequency (F) to obtain the frequency offset value (F) of the crystal-free Bluetooth chip. offset ).

6. The frequency offset compensation method for a crystal-free Bluetooth chip based on CBPF as described in any one of claims 1-3, characterized in that, Also includes: The external precision clock and phase-locked loop unit are switched on by a switching switch, or the internal LC oscillator and phase-locked loop unit are switched on, so that the first sine wave signal sequence or the second sine wave signal sequence is provided to the complex bandpass filter (CBPF) by the phase-locked loop unit, respectively.

7. A frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF, characterized in that, include: The first sine wave generation module (100) is used to generate a series of first sine wave signal sequences with different frequencies using an external precision clock as a clock source; A first sine wave providing module (200) is used to sequentially provide the first sine wave signal sequence to a complex bandpass filter (CBPF), wherein the center frequency (F) of the complex bandpass filter (CBPF) is... c Size adjustable; The first waveform acquisition module (300) is used to acquire several first output waveforms of the complex bandpass filter (CBPF); Center frequency adjustment module (400) is used to adjust the center frequency (F) of the complex bandpass filter (CBPF) according to the plurality of first output waveforms. c ), so that the adjusted center frequency (F) c The frequency (F) is equal to the target frequency. The second sine wave generation module (500) is used to generate a series of second sine wave signal sequences with different frequencies using the internal LC oscillator of the crystalless Bluetooth chip as a clock source. The second sine wave providing module (600) is used to sequentially provide the second sine wave signal sequence to the complex bandpass filter (CBPF); The second waveform acquisition module (700) is used to acquire several second output waveforms of the complex bandpass filter (CBPF); Frequency offset determination module (800), used to determine the frequency offset value based on the plurality of second output waveforms relative to the adjusted center frequency (F). c The frequency offset is used to determine the frequency offset value of the crystalless Bluetooth chip, so as to compensate the LC oscillator according to the frequency offset value.

8. The frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF as described in claim 7, characterized in that, In the first sine wave generation module (100), the intensity of each sine wave signal in the first sine wave signal sequence is the same; In the center frequency adjustment module (400), the frequency corresponding to the first output waveform with the strongest signal strength among the plurality of first output waveforms is taken as the center frequency (F). c ).

9. The frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF as described in claim 8, characterized in that, The center frequency adjustment module (400) includes: The determination unit is used to determine the center frequency (F). c Is the center frequency (F) equal to the target frequency (F)? c If the center frequency (F) equals the target frequency (F), then the frequency determination unit is executed; if the center frequency (F) c If the frequency is not equal to the target frequency (F), then the frequency adjustment unit is executed; The frequency determination unit is used to determine the current center frequency (F). c ) as the adjusted center frequency (F c ); The frequency adjustment unit is used to adjust the current center frequency (F). c After that, the first sine wave generation module (100), the first sine wave providing module (200), the first waveform acquisition module (300), and the judgment unit are repeatedly executed until the center frequency (F) is reached. c ) equals the target frequency (F).

10. The frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF as described in any one of claims 7-9, characterized in that, In the second sine wave generation module (500), the frequency range of the second sine wave signal sequence covers the frequency offset range of the LC oscillator.

11. The frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF as described in any one of claims 7-9, characterized in that, The frequency offset value determination module (800) is specifically used for: Measure the signal strength of the plurality of second output waveforms; The frequency corresponding to the second output waveform with the strongest signal strength is taken as the single-pass signal frequency (F'); The frequency offset (F') of the crystal-free Bluetooth chip is obtained by subtracting the single-pass signal frequency (F') from the target frequency (F). offset ).

12. The frequency offset compensation device for a crystal-free Bluetooth chip based on CBPF as described in any one of claims 7-9, characterized in that, Also includes: The switching module is used to switch between the external precision clock and the phase-locked loop unit, or to switch between the internal LC oscillator and the phase-locked loop unit, so as to provide the first sine wave signal sequence or the second sine wave signal sequence to the complex bandpass filter (CBPF) using the phase-locked loop unit, respectively.

13. A computer device, characterized in that, include: Frequency offset compensation for a crystal-free Bluetooth chip based on CBPF can be performed using the method described in any one of claims 1-6, or the apparatus described in any one of claims 7-12 can be used.

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

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