阅读说明：本技术 晶振频率校准方法、装置以及电子设备 (Crystal oscillator frequency calibration method and device and electronic equipment ) 是由 许百成 邓祝明 于 2018-07-18 设计创作，主要内容包括：本公开涉及一种晶振频率校准方法、装置以及电子设备,属于电子技术领域,能够自适应地对晶振的频率进行校准,进而能够使使用晶振的电子设备处于频率捕获阶段的时长缩短,有利于减小电子设备的功耗并降低产品复杂度。该方法包括：在频率跟踪阶段期间,采集晶振的频率偏移值以及该频率偏移值所对应的温度和时间；基于采集到的频率偏移值、温度和时间进行拟合,得到所述晶振的频率偏移值随着温度和时间变化的函数；利用所得到的函数来校准所述晶振的频率。(The invention relates to an crystal oscillator frequency calibration method, an apparatus and an electronic device, belonging to the electronic technical field, which can adaptively calibrate the frequency of a crystal oscillator, further shorten the time length of the electronic device using the crystal oscillator in a frequency acquisition stage, and is beneficial to reducing the power consumption of the electronic device and reducing the product complexity.)

A method for calibrating the frequency of a crystal, the method comprising:

during the frequency tracking stage, acquiring a frequency deviation value of a crystal oscillator and the temperature and time corresponding to the frequency deviation value;

fitting is carried out based on the collected frequency deviation value, the temperature and the time to obtain a function of the frequency deviation value of the crystal oscillator along with the change of the temperature and the time;

the frequency of the crystal oscillator is calibrated using the resulting function.

2. The method of claim 1, wherein the acquiring the frequency offset value of the crystal oscillator and the temperature and time corresponding to the frequency offset value during the frequency tracking phase comprises:

during the frequency tracking stage, regularly collecting the frequency deviation value of the crystal oscillator and the temperature and time corresponding to the frequency deviation value; and/or

And acquiring a frequency deviation value of the crystal oscillator and the temperature and time corresponding to the frequency deviation value when the frequency acquisition stage is completed and the frequency tracking stage is just started each time.

3. The method of claim 1, further comprising: by triplets { e_k，x_k，y_kStoring the collected frequency deviation value, temperature and time in the form of:

where K represents the maximum number of stores of the triplet, e_k、x_k、y_kRespectively representing the k-th frequency offset value, temperature and time,

4. The method of claim 3, wherein fitting based on the collected frequency offset value, temperature and time to obtain the function of the frequency offset value of the crystal oscillator with temperature and time comprises:

selecting N triples from the stored K triples;

and fitting the selected N triples by using a binary prediction method to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of temperature and time.

5. The method of claim 4, wherein N triples are selected from the stored K triples as follows:

(1)N≤K

(2) n is more than or equal to the number of parameters to be estimated in the binary function

(3) The N triples are the latest N triples, or the temperature value of each of the N triples is closest to the current temperature.

6. The method according to claim 4 or 5, characterized in that the binary function is of the form:

F(x，y)＝D(x)+A(y)

wherein d (x) represents a frequency shift function caused by temperature drift, and x represents a temperature variable; a (y) represents a frequency shift function caused by aging, and y represents a time variable.

7. The method according to claim 4 or 5, wherein the fitting the selected N triples by using a binary prediction method to obtain a binary function of the frequency offset value of the crystal oscillator along with the change of temperature and time comprises:

and fitting the selected N triples by using a binary prediction method according to a least square criterion to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of temperature and time.

An apparatus for calibrating the frequency of a crystal, the apparatus comprising:

the acquisition module is used for acquiring a frequency deviation value of the crystal oscillator and the temperature and time corresponding to the frequency deviation value during a frequency tracking stage;

the fitting module is used for fitting based on the frequency deviation value, the temperature and the time acquired by the acquisition module to obtain a function of the frequency deviation value of the crystal oscillator along with the change of the temperature and the time;

and the calibration module is used for calibrating the frequency of the crystal oscillator by using the obtained function.

9. The apparatus of claim 8, wherein the acquisition module is further configured to:

during the frequency tracking stage, regularly collecting the frequency deviation value of the crystal oscillator and the temperature and time corresponding to the frequency deviation value; and/or

And acquiring a frequency deviation value of the crystal oscillator and the temperature and time corresponding to the frequency deviation value when the frequency acquisition stage is completed and the frequency tracking stage is just started each time.

10. The apparatus of claim 8, further comprising a storage module configured to store the triplet { e }_k，x_k，y_kStoring the frequency deviation value, the temperature and the time acquired by the acquisition module in the form of:

where K represents the maximum number of stores of the triplet, e_k、x_k、y_kRespectively representing the k-th frequency offset value, temperature and time,

11. The apparatus of claim 10, wherein the fitting module comprises:

the triple selecting submodule is used for selecting N triples from the K triples stored by the storage module;

and the fitting submodule is used for fitting the N triples selected by the triplet selection submodule by using a binary prediction method to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of temperature and time.

12. The apparatus of claim 11, wherein the triple selection sub-module selects N triples from the K triples stored in the storage module as follows:

(1)N≤K

(2) n is more than or equal to the number of parameters to be estimated in the binary function

(3) The N triples are the latest N triples, or the temperature value of each of the N triples is closest to the current temperature.

13. The apparatus according to claim 11 or 12, wherein the binary function is of the form:

F(x，y)＝D(x)+A(y)

wherein d (x) represents a frequency shift function caused by temperature drift, and x represents a temperature variable; a (y) represents a frequency shift function caused by aging, and y represents a time variable.

14. The apparatus according to claim 11 or 12, wherein the fitting sub-module is further configured to fit the N triples selected by the triplet selecting sub-module by using a binary prediction method according to a least square criterion, so as to obtain a binary function of the frequency deviation value of the crystal oscillator along with changes of temperature and time.

An electronic device of 15, , comprising the crystal frequency calibration apparatus of any of claims 8 to 14, wherein the crystal frequency calibration apparatus is a crystal frequency calibration apparatus of any of claims .

Technical Field

The present disclosure relates to the field of electronic technologies, and in particular, to a method and an apparatus for calibrating crystal oscillation frequency, and an electronic device.

Background

Crystal oscillators, also known as crystal resonators, are electronic components used to generate frequency signals. The frequency of the crystal oscillator changes along with the change of temperature, and the phenomenon is called temperature drift, temperature drift for short; meanwhile, the frequency of the crystal oscillator also changes with the passage of time, and this phenomenon is called aging.

Crystal oscillator at reference temperature T₀Reference frequency of₀. The relative frequency change caused by temperature drift and aging is generally an absolute frequency offset value Δ f and a reference frequency f₀Is expressed by the ratio of (i) to (ii)

In ppm ( parts per million) for example, reference frequencies are f₀When the absolute frequency offset value of the crystal oscillator is Δ f 26Hz at 26MHz, the relative frequency thereof changes to

Herein, without being particularly described, the frequency offset value is defaulted to a relative frequency offset value.

If the crystal oscillator has a large frequency offset caused by temperature drift and aging, for example, the value may be between 0ppm and 20ppm or even higher, when the wireless communication terminal is powered on and enters a frequency acquisition stage, the time length of the wireless communication terminal in the frequency acquisition stage may be prolonged, thereby increasing the power consumption and product complexity of the wireless communication terminal.

Disclosure of Invention

A wireless communication terminal will typically be in several phases:

(1) and (3) closing state: in this stage, the wireless communication terminal is not started up and the crystal oscillator does not work.

(2) A frequency acquisition stage: in this phase, the wireless communication terminal is powered on and captures the frequency of the reference signal source (e.g., by capturing the base station downlink signal to capture the reference signal source) to calibrate the frequency of the crystal oscillator. However, if the frequency offset of the crystal oscillator is large before the power-on start-up, the time for the frequency acquisition phase is long.

(3) A frequency tracking stage: in this phase, the wireless communication terminal is already operating normally and will track the frequency of the reference signal source to ensure that the crystal oscillator operates within a very small frequency deviation range.

Therefore, it would be advantageous if the frequency offset of the crystal oscillator detected in the past frequency tracking phase could be used to calibrate the crystal oscillator frequency prior to powering up the wireless communication terminal.

Therefore, an object of the present disclosure is to provide crystal oscillator frequency calibration method, device and electronic device, which can adaptively calibrate the frequency of the crystal oscillator, and further shorten the time of the electronic device using the crystal oscillator in the frequency capture phase, thereby being beneficial to reducing the power consumption of the electronic device and reducing the product complexity.

According to an embodiment of the disclosure, a method for calibrating a frequency of a crystal oscillator is provided, the method includes collecting a frequency offset value of the crystal oscillator and a temperature and a time corresponding to the frequency offset value during a frequency tracking phase, fitting based on the collected frequency offset value, the temperature and the time to obtain a function of the frequency offset value of the crystal oscillator along with the temperature and the time, and calibrating the frequency of the crystal oscillator by using the obtained function.

Optionally, the acquiring a frequency offset value of the crystal oscillator and a temperature and time corresponding to the frequency offset value during the frequency tracking phase includes: during a frequency tracking stage, regularly acquiring a frequency deviation value of the crystal oscillator and a temperature and time corresponding to the frequency deviation value; and/or acquiring the frequency deviation value of the crystal oscillator and the temperature and time corresponding to the frequency deviation value when the frequency acquisition stage is completed and the frequency tracking stage is just entered.

Optionally, the method further comprises: by triplets { e_k,x_k,y_kStoring the collected frequency deviation value, temperature and time in the form of:

where K represents the maximum number of stores of the triplet, e_k、x_k、y_kRespectively representing the k-th frequency offset value, temperature and time,

respectively representing the frequency offset value, temperature and time at the latest acquisition instant.

Optionally, the fitting based on the collected frequency deviation value, temperature and time to obtain a function of the frequency deviation value of the crystal oscillator along with changes of the temperature and the time includes: selecting N triples from the stored K triples; and fitting the selected N triples by using a binary prediction method to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of temperature and time.

Optionally, N triples are selected from the stored K triples as follows:

(1)N≤K

(2) n is more than or equal to the number of parameters to be estimated in the binary function

(3) The N triples are the latest N triples, or the temperature value of each of the N triples is closest to the current temperature.

Optionally, the binary function is of the form:

F(x,y)＝D(x)+A(y)

wherein d (x) represents a frequency shift function caused by temperature drift, and x represents a temperature variable; a (y) represents a frequency shift function caused by aging, and y represents a time variable.

Optionally, the fitting the selected N triples by using a binary prediction method to obtain a binary function of the frequency offset value of the crystal oscillator along with the change of the temperature and the time includes: and fitting the selected N triples by using a binary prediction method according to a least square criterion to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of temperature and time.

According to a second embodiment of the disclosure, an crystal oscillator frequency calibration device is provided, the device includes an acquisition module configured to acquire a frequency offset value of a crystal oscillator and a temperature and a time corresponding to the frequency offset value during a frequency tracking phase, a fitting module configured to perform fitting based on the frequency offset value, the temperature and the time acquired by the acquisition module to obtain a function of the frequency offset value of the crystal oscillator along with changes of the temperature and the time, and a calibration module configured to calibrate the frequency of the crystal oscillator by using the obtained function.

Optionally, the acquisition module is further configured to: during a frequency tracking stage, regularly acquiring a frequency deviation value of the crystal oscillator and a temperature and time corresponding to the frequency deviation value; and/or acquiring the frequency deviation value of the crystal oscillator and the temperature and time corresponding to the frequency deviation value when the frequency acquisition stage is completed and the frequency tracking stage is just entered.

Optionally, the apparatus further comprises a storage module for storing the triplet { e }_k,x_k,y_kStoring the frequency deviation value, the temperature and the time acquired by the acquisition module in the form of:

where K represents the maximum number of stores of the triplet, e_k、x_k、y_kRespectively representing the k-th frequency offset value, temperature and time,

respectively representing the frequency offset value, temperature and time at the latest acquisition instant.

Optionally, the fitting module comprises: the triple selecting submodule is used for selecting N triples from the K triples stored by the storage module; and the fitting submodule is used for fitting the N triples selected by the triplet selection submodule by using a binary prediction method to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of temperature and time.

Optionally, the triple selecting sub-module selects N triples from the K triples stored in the storage module as follows:

(1)N≤K

(2) n is more than or equal to the number of parameters to be estimated in the binary function

(3) The N triples are the latest N triples, or the temperature value of each of the N triples is closest to the current temperature.

Optionally, the binary function is of the form:

F(x,y)＝D(x)+A(y)

wherein d (x) represents a frequency shift function caused by temperature drift, and x represents a temperature variable; a (y) represents a frequency shift function caused by aging, and y represents a time variable.

Optionally, the fitting sub-module is further configured to fit the N triples selected by the triplet selecting sub-module by using a binary prediction method according to a least square criterion, so as to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of temperature and time.

According to a third embodiment of the present disclosure, electronic devices are provided, which include the crystal frequency calibration apparatus according to the second embodiment of the present disclosure.

By adopting the technical scheme, the frequency deviation value of the crystal oscillator can be fitted based on the frequency deviation value, the temperature and the time collected during the frequency tracking stage to obtain the function of the frequency deviation value of the crystal oscillator along with the change of the temperature and the time, and then the frequency of the crystal oscillator is calibrated by using the obtained function, so that the frequency of the crystal oscillator can be adaptively and accurately calibrated, particularly, the frequency of the crystal oscillator can be adaptively and accurately calibrated before the electronic equipment is started, the possible range of the frequency deviation value of the crystal oscillator is obviously reduced, the duration of the electronic equipment in the frequency capturing stage can be further shortened, the power consumption of the electronic equipment is reduced, and the product complexity is reduced.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification , which together with the following detailed description serve to explain, but are not to be construed as limiting, the disclosure.

Fig. 1 shows a flow chart of a crystal oscillator frequency calibration method according to embodiments of the present disclosure.

Fig. 2 illustrates a flow chart of a crystal oscillator frequency calibration method according to yet another embodiment of the present disclosure.

Fig. 3 shows a schematic block diagram of a crystal frequency calibration apparatus according to embodiments of the present disclosure.

Fig. 4 shows a schematic block diagram of a crystal frequency calibration apparatus according to yet another embodiment of the present disclosure.

Fig. 5 shows a schematic block diagram of a fitting module in a crystal frequency calibration apparatus according to an embodiment of the present disclosure.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

Fig. 1 shows a flowchart of a crystal frequency calibration method according to embodiments of the present disclosure, and as shown in fig. 1, the method may include the following steps S11 to S13.

In step S11, during the frequency tracking phase, a frequency offset value of the crystal oscillator and a temperature and a time corresponding to the frequency offset value are collected.

That is, in this step, the frequency offset value of the crystal oscillator and the temperature and time corresponding to the frequency offset value may be collected during the frequency tracking phase of the electronic device using the crystal oscillator.

The electronic device using the crystal oscillator may be various wireless communication terminals or wired communication terminals, such as a mobile phone, an internet of things terminal, and the like.

When the electronic equipment using the crystal oscillator is in a frequency tracking phase, the electronic equipment tracks the reference signal source in real time, for example, tracks the reference signal source in real time by using a base station downlink signal, so as to calibrate the frequency of the crystal oscillator in real time by using the tracked frequency of the reference signal source. Therefore, in this case, the crystal oscillator frequency calibration method according to the embodiment of the present disclosure may perform the acquisition of the frequency offset value of the crystal oscillator, for example, the frequency of the reference signal source and the frequency of the crystal oscillator may be obtained, and then the frequency offset value of the crystal oscillator is obtained by using the two frequencies; the crystal oscillator frequency calibration method according to the embodiment of the disclosure can also acquire the current temperature and time corresponding to the frequency offset value at the same time.

For example, the time between the current acquisition time and the factory time can be defined as the time acquired at the current acquisition time, and for example, the time between the th acquisition time can be defined as zero, and then the time between each subsequent acquisition time and the th acquisition time can be defined as the time acquired at the current acquisition time.

In step S12, a fitting is performed based on the collected frequency offset value, temperature and time, and a function of the frequency offset value of the crystal oscillator with temperature and time is obtained.

In step S13, the frequency of the crystal oscillator is calibrated using the obtained function.

By adopting the technical scheme, the frequency deviation value of the crystal oscillator can be fitted based on the frequency deviation value, the temperature and the time collected during the frequency tracking stage to obtain the function of the frequency deviation value of the crystal oscillator along with the change of the temperature and the time, and then the frequency of the crystal oscillator is calibrated by using the obtained function, so that the frequency of the crystal oscillator can be adaptively and accurately calibrated, particularly, the frequency of the crystal oscillator can be adaptively and accurately calibrated before the electronic equipment is started, the possible range of the frequency deviation value of the crystal oscillator is obviously reduced, the duration of the electronic equipment in the frequency capturing stage can be further shortened, the power consumption of the electronic equipment is reduced, and the product complexity is reduced.

In possible embodiments, the acquiring of the frequency offset value of the crystal oscillator and the temperature and time corresponding to the frequency offset value during the frequency tracking phase described in step S11 may be implemented in various ways, for example, it may be implemented in implementations as follows, or may be implemented in a combination of several implementations as follows:

(1) and during the frequency tracking phase, periodically acquiring the frequency offset value of the crystal oscillator and the temperature and time corresponding to the frequency offset value. For example, the collection may be performed daily, weekly, biweekly, monthly. This is particularly applicable to electronic devices such as cell phones and the like which are frequently used in daily life.

(2) The method is particularly suitable for equipment with lower communication frequency, such as Internet of things equipment with automatic meter reading, and the equipment communicates times each month.

In possible implementation manners, the crystal oscillator frequency calibration method according to the embodiment of the disclosure may further include a step of calibrating the crystal oscillator frequency by using the triplet { e }_k,x_k,y_kStoring the collected frequency deviation value, temperature and time in the form of:

where K represents the maximum number of triplets stored, i.e. up to K triplets of data may be stored in the memory of the electronic device, for example. Since the number of the collected triples is increased with the passage of time, the oldest stored triplet data can be deleted, so that the newly collected triplet data can be stored in the memory. Therefore, not only is too much storage space required for storing the acquired ternary group data, but also fresh ternary groups can be used in the subsequent fitting processAnd the data of the three groups are fitted to ensure that the referential value of the data of the three groups is higher. Moreover, the stored K ternary sets of data are not lost with the power down of the electronic device. Triple e_k,x_k,y_kThree elements of e_k、x_k、y_kRespectively representing the k-th frequency offset value, temperature and time,

respectively representing the frequency offset value, temperature and time at the latest acquisition instant.

Fig. 2 shows a flowchart of a crystal oscillator frequency calibration method according to yet another embodiment of the present disclosure, which may include the following steps, as shown in fig. 2:

in step S21, during the frequency tracking phase, a frequency offset value of the crystal oscillator and a temperature and a time corresponding to the frequency offset value are collected.

Assuming that the time acquisition time is defined as zero, time acquisition time is 1/2018 and times per month, the time acquisition time is 0, the acquired temperature is the current temperature at the acquisition time, the second time acquisition time is 2/1/2018, the current acquisition time is 31 days, and the acquired temperature is the current temperature at the acquisition time, and so on.

In step S22, the triplet { e }_k,x_k,y_kStore the collected frequency offset value, temperature and time. Among them, it is preferable to store K triple data at most. The storage form of which has been described in detail above.

In step S23, N triples are selected from the K stored triples.

Preferably, the N triples are selected from the stored K triples as follows:

(1)N≤K

(2) n is more than or equal to the number of parameters to be estimated in the binary function

(3) The N triples are the latest N triples, or the temperature value of each of the N triples is closest to the current temperature.

For example, assume that a maximum of 10 triples can be stored and the number of parameters to be estimated in the binary function is 4. Then, the number of the selected triples should be at least 4 and should be less than or equal to 10, for example, 4, 5, 10, etc. may be selected; moreover, the selected triplet may be the latest triplet, or the temperature value of each triplet in the selected triplet is closest to the current temperature. For example, if 10 triples of data are provided, the collection time of each of the triples is 1 month and 1 day, 1 month and 8 days, 1 month and 15 days, 1 month and 22 days, 1 month and 29 days, 2 months and 5 days, 2 months and 12 days, 2 months and 19 days, 2 months and 26 days, and 3 months and 5 days in 2018, 4 triples of data need to be selected, the triples of data collected in 2 months and 12 days, 2 months and 19 days, 2 months and 26 days, and 3 months and 5 days in 2018, or the triples of which the temperature is closest to the temperature (for example, 26 degrees) at which the crystal oscillation frequency needs to be calibrated are selected from the triples collected in 1 month and 1 day to 3 months and 5 days in 2018.

In step S24, fitting the N selected triplets by using a binary prediction method to obtain a binary function of the frequency offset value of the crystal oscillator along with the change of temperature and time.

First, a pre-defined bivariate model is required before fitting. Since the frequency offset e is composed of two parts, i.e. the frequency offset caused by the temperature drift

And aging induced frequency offset value

That is to say that the position of the first electrode,

thus, the bivariate model may be predefined as follows:

F(x,y)＝D(x)+A(y)(3)

wherein d (x) represents a frequency shift function caused by temperature drift, and x represents a temperature variable; a (y) represents a frequency shift function caused by aging, and y represents a time variable.

Second, when fitting, the various parameters in the predefined bivariate model may be fitted according to, for example, least squares criteria. The following examples are given.

Assume that the frequency shift function due to temperature drift is:

D(x)＝d₂(x-T₀)²+d₁(x-T₀)(4)

assume that the frequency offset function caused by aging is:

A(x)＝a₁log(y)+a₀(5)

then, substituting equations (4) and (5) into equation (3) yields:

F(x,y)＝d₂(x-T₀)²+d₁(x-T₀)+a₁log(y)+a₀(6)

wherein, T₀Represents a reference temperature (known); d₂、d₁、a₁、a₀Parameters needing fitting in the binary function model are obtained; log (-) denotes a base-10 logarithmic function.

Substituting the selected N ternary sets of data into formula (6) and writing the data into a matrix form as follows:

order:

then equation (7) may be changed to:

E＝SC(11)

according to the least square standardThen, the parameter d to be fitted in the binary function model is calculated₂、d₁、a₁、a₀The method comprises the following steps:

wherein, (.)^TRepresenting the transpose of the matrix.

In step S25, the frequency of the crystal oscillator is calibrated by using the obtained binary function.

After the parameters to be fitted in the bigram function model are calculated, the bigram function model can be used to calibrate the frequency of the crystal oscillator, for example, the temperature value at the current moment

And time valueSubstituting into the binary function model to calculate the current crystal oscillation frequency offset value

And then, in a time period before the electronic equipment is started, the frequency of the crystal oscillator can be calibrated by utilizing the calculated frequency offset value so as to obviously reduce the possible range of the frequency offset value of the crystal oscillator, further shorten the time of the electronic equipment in a frequency capturing stage, and be beneficial to reducing the power consumption of the electronic equipment and reducing the product complexity.

Fig. 3 shows a schematic block diagram of a crystal frequency calibration apparatus according to embodiments of the present disclosure, which may include, as shown in fig. 3:

the acquisition module 31 is configured to acquire a frequency offset value of the crystal oscillator and a temperature and time corresponding to the frequency offset value during a frequency tracking phase;

a fitting module 32, configured to perform fitting based on the frequency deviation value, the temperature, and the time acquired by the acquisition module 31, so as to obtain a function of the frequency deviation value of the crystal oscillator along with changes of the temperature and the time;

a calibration module 33 for calibrating the frequency of the crystal oscillator using the obtained function.

By adopting the above technical scheme, since the fitting module 32 can perform fitting based on the frequency deviation value, the temperature and the time acquired during the frequency tracking phase to obtain a function of the frequency deviation value of the crystal oscillator along with the change of the temperature and the time, and then the calibration module 33 can calibrate the frequency of the crystal oscillator by using the obtained function, the frequency of the crystal oscillator can be adaptively and accurately calibrated, especially the frequency of the crystal oscillator can be adaptively and accurately calibrated before the electronic device is started, the possible range of the frequency deviation value of the crystal oscillator is obviously reduced, and further, the duration of the electronic device in the frequency capturing phase can be shortened, which is beneficial to reducing the power consumption of the electronic device and reducing the complexity of products.

Optionally, the acquisition module 31 may be further configured to: during a frequency tracking stage, regularly acquiring a frequency deviation value of the crystal oscillator and a temperature and time corresponding to the frequency deviation value; and/or acquiring the frequency deviation value of the crystal oscillator and the temperature and time corresponding to the frequency deviation value when the frequency acquisition stage is completed and the frequency tracking stage is just entered.

FIG. 4 shows a schematic block diagram of a crystal frequency calibration apparatus according to yet another embodiment of the present disclosure, which may further include a storage module 34 for storing the triples { e } as shown in FIG. 4_k,x_k,y_kThe frequency offset value, the temperature and the time acquired by the acquisition module 31 are stored in the form of:

where K represents the maximum number of stores of the triplet, e_k、x_k、y_xRespectively represents the k-th frequency deviation value and temperatureThe degree and the time of the process are,respectively representing the frequency offset value, temperature and time at the latest acquisition instant.

Fig. 5 shows a schematic block diagram of a fitting module in the crystal frequency calibration apparatus according to the embodiment of the disclosure, and as shown in fig. 5, the fitting module 32 may include:

the triple selecting submodule 32a is configured to select N triples from the K triples stored in the storage module 34;

and the fitting submodule 32b is configured to fit the N triples selected by the triplet selecting submodule 32a by using a binary prediction method, so as to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of temperature and time.

Optionally, the triple selecting sub-module 32a selects N triples from the K triples stored in the storage module 34 as follows:

(1)N≤K

(2) n is more than or equal to the number of parameters to be estimated in the binary function

(3) The N triples are the latest N triples, or the temperature value of each of the N triples is closest to the current temperature.

Optionally, the binary function is of the form:

F(x,y)＝D(x)+A(y)(15)

wherein d (x) represents a frequency shift function caused by temperature drift, and x represents a temperature variable; a (y) represents a frequency shift function caused by aging, and y represents a time variable.

Optionally, the fitting sub-module 32b is further configured to fit the N triples selected by the triplet selecting sub-module by using a binary prediction method according to a least square criterion, so as to obtain a binary function of the frequency deviation value of the crystal oscillator along with the change of the temperature and the time.

The specific implementation manner of the operations performed by each module in the crystal oscillator frequency calibration apparatus according to the embodiment of the present disclosure has been described in detail in the crystal oscillator frequency calibration method according to the embodiment of the present disclosure, and is not described herein again.

According to yet another embodiment of the present disclosure, kinds of electronic devices are also provided, which may include the crystal frequency calibration apparatus according to the embodiment of the present disclosure described above.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, various possible combinations will not be separately described in this disclosure.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.