Carrier frequency offset compensation method, device, equipment, medium and program product

Abstract

The application relates to the technical field of radio frequency communication, and provides a carrier frequency offset compensation method, device, equipment, medium and program product.The method comprises the following steps: if radio frequency operation is performed within a preset time length after a radio frequency module is started, frequency offset compensation is performed on a first subframe of the radio frequency operation according to a normalized frequency offset; the normalized frequency offset is obtained by dividing a historical carrier frequency offset value by a historical carrier frequency; the historical carrier frequency offset value is a carrier frequency offset value obtained by measuring the carrier frequency offset of the first subframe within a preset time length after a historical radio frequency module is started; the historical carrier frequency is a carrier frequency of the historical radio frequency module; the radio frequency parameters of the historical radio frequency module are the same as the radio frequency parameters of the radio frequency module; and frequency offset compensation is performed on subframes other than the first subframe in the radio frequency operation according to a preset automatic frequency control method. In this way, the first subframe of the radio frequency operation can be effectively compensated, and the residual carrier frequency offset of the first subframe is significantly reduced.

Description

Technical Field

[0001] This application relates to the field of radio frequency communication technology, and more specifically, to a carrier frequency offset compensation method, apparatus, device, medium, and program product. Background Technology

[0002] In LTE (Long Term Evolution) wireless communication systems, UE (User Equipment) and base stations communicate via radio frequency signals to exchange data and achieve wireless communication.

[0003] Typically, during data exchange between the base station and the UE, the user terminal needs to dynamically adjust its radio frequency operation based on the base station's signaling. At this time, the phase-locked loop (PLL) locks its local oscillator frequency to the carrier frequency of the base station's downlink signal by configuring its division ratio and loop parameters. This process relies on the stability of the reference clock provided by the passive crystal.

[0004] Existing technologies typically rely on AFC (Automatic Frequency Control) to correct frequency offset. AFC forms a closed-loop system by periodically measuring the frequency offset between the downlink reference signal and the local clock to adjust the local carrier frequency, thereby maintaining synchronization between the local oscillator frequency and the carrier frequency of the base station downlink signal.

[0005] However, when the RF module is enabled, sudden changes in chip current can cause a drop in power supply voltage and temperature changes. These factors can cause additional frequency offset in the reference clock output of the passive crystal, which in turn causes the output frequency of the carrier PLL to deviate significantly from the target value.

[0006] If the historical AFC value is used to compensate for the frequency offset of the first subframe, the historical AFC value has already converged to a stable value. Therefore, the historical AFC value may not be able to effectively compensate for the frequency offset of the first subframe, and the carrier frequency of the first subframe may still deviate significantly from the target value. Summary of the Invention

[0007] The purpose of this application is to provide a carrier frequency offset compensation method, apparatus, device, medium, and program product to solve the problem that the related technology may not be able to effectively compensate for the carrier frequency offset of the first subframe after the radio frequency module is enabled.

[0008] This application provides a carrier frequency offset compensation method based on an LTE system. The LTE system includes a user terminal, a base station, and a radio frequency module for realizing wireless communication between the user terminal and the base station. The method includes: If an RF operation is performed within a preset time after the RF module is started, frequency offset compensation will be performed for the first subframe of the RF operation based on the preset normalized frequency offset. The normalized frequency offset is obtained by dividing the historical carrier frequency offset value by the historical carrier frequency. The historical carrier frequency offset value is obtained by measuring the carrier frequency offset in the first subframe within a preset time period after the historical radio frequency module is started. The historical carrier frequency is the carrier frequency of the historical radio frequency module. The start time of the historical radio frequency module is earlier than the start time of the radio frequency module, and the radio frequency parameters of the historical radio frequency module are the same as those of the radio frequency module. Frequency offset compensation is performed on subframes other than the first subframe in the radio frequency operation according to the preset automatic frequency control method.

[0009] In the above implementation, the carrier frequency offset compensation method provided in this application embodiment has a small deviation between the normalized frequency offset of the first subframe after the historical radio frequency module starts and the normalized frequency offset of the first subframe within a preset time period after the radio frequency module starts in this application, since the radio frequency parameters of the historical radio frequency module are the same as those of the radio frequency module. Therefore, in this application, the normalized frequency offset of the first subframe after the historical radio frequency module starts can be regarded as the normalized frequency offset of the first subframe after the radio frequency module starts in this application. Simultaneously, since the startup time of the historical radio frequency module is earlier than the startup time of the radio frequency module, the carrier frequency offset of the first subframe within a preset time period after the historical radio frequency module starts can be measured in advance before the radio frequency module in this application performs radio frequency operation. The historical carrier frequency offset value is then obtained by dividing the historical carrier frequency offset value by the historical carrier frequency. This allows for the prediction of the normalized frequency offset of the first subframe after the radio frequency module starts in advance before the radio frequency module in this application performs radio frequency operation. Based on the estimated normalized frequency offset of the first subframe after the RF module starts, this normalized frequency offset can be used to compensate for the frequency offset of the first subframe of RF operation, thereby effectively compensating for the frequency offset of the RF module in the first subframe after startup. Furthermore, when using the automatic frequency control method to compensate for the frequency offset of subframes other than the first subframe in RF operation, since the residual carrier frequency offset of the first subframe has been significantly reduced, the actual carrier frequency offset of the first subframe detected by the automatic frequency control method can also be significantly reduced, thus enabling AFC to converge to a stable value more quickly.

[0010] Furthermore, frequency offset compensation is performed on the first subframe of the radio frequency operation according to the preset normalized frequency offset, including: determining the target frequency division ratio according to the normalized frequency offset; and controlling the radio frequency module to send the first subframe according to the target frequency division ratio.

[0011] Since the frequency division ratio can determine the carrier frequency of the RF module, in the above implementation, by determining the target frequency division ratio based on the normalized frequency offset and controlling the RF module to send the first subframe according to the target frequency division ratio, the carrier frequency offset of the first subframe of the RF module can be adjusted during the generation stage of the first subframe, avoiding the impact of dynamically adjusting the frequency offset in the middle of the subframe on signal demodulation.

[0012] Further, determining the target frequency division ratio based on the normalized frequency offset includes: Obtain the carrier frequency of the radio frequency module; The first frequency offset compensation value is obtained by multiplying the normalized frequency offset by the carrier frequency; The frequency division ratio to be adjusted is obtained by dividing the first frequency offset compensation value by the preset reference clock frequency in the radio frequency module. The preset division ratio in the radio frequency module is corrected using the division ratio to be adjusted to obtain the target division ratio.

[0013] In the above implementation, since the carrier frequency offset varies proportionally to the carrier frequency, and the normalized frequency offset is obtained after removing the influence of the carrier frequency on the carrier frequency offset, after obtaining the carrier frequency of the RF module and the predicted normalized frequency offset, the actual frequency offset prediction value (corresponding to the first frequency offset compensation value) can be obtained by multiplying the carrier frequency of the RF module by the normalized frequency offset. Based on the actual frequency offset prediction value, the RF module can be frequency offset compensated. In the above implementation, the first frequency offset compensation value is divided by the preset reference clock frequency in the RF module to obtain the frequency division ratio to be adjusted; the preset frequency division ratio in the RF module is corrected using the frequency division ratio to be adjusted to obtain the target frequency division ratio, so that the RF module can generate the first subframe using the target frequency division ratio, thereby achieving pre-compensation for the first subframe and avoiding the impact of dynamic frequency offset adjustment in the middle of the subframe on signal demodulation.

[0014] Furthermore, before performing frequency offset compensation for the first subframe of the radio frequency operation based on the preset normalized frequency offset, the following steps are also included: Obtain the radio frequency parameters of the radio frequency module, including the radio frequency operation type and carrier frequency type; In a preset data table, the radio frequency parameters are used to perform a matching operation to obtain the normalized frequency offset; the data table stores the radio frequency parameters, the normalized frequency offset, and the correspondence between the two.

[0015] In the above implementation, the normalized frequency offset is obtained by matching the radio frequency parameters of the radio frequency module in the data table. This allows for rapid compensation of the ground frequency offset of the first subframe using the normalized frequency offset.

[0016] Furthermore, the carrier frequency offset compensation method based on the LTE system also includes: Obtain the first actual frequency offset value of the first subframe of the radio frequency module; The normalized frequency offset in the data table is updated based on the first actual frequency offset value.

[0017] In the above implementation, the first actual frequency offset value of the first subframe of the RF module is obtained, and the normalized frequency offset in the data table is updated using the first actual frequency offset value. This ensures that the normalized frequency offset stored in the data table is the most recently measured normalized frequency offset, reducing the impact of time factors on the normalized frequency offset. This allows for a more accurate prediction of the actual carrier frequency offset of the first subframe within a preset time after the second startup of the RF module, thereby enabling more accurate frequency offset compensation for the first subframe within the preset time after the second startup of the RF module.

[0018] In the above implementation, updating the normalized frequency offset based on the first actual frequency offset value includes: The initial frequency offset value is obtained by dividing the first actual frequency offset value by the carrier frequency; The initial frequency offset value is smoothed over time using the normalized frequency offset to obtain the target frequency offset value. Replace the normalized frequency offset in the data table with the target frequency offset value.

[0019] In the above implementation, since the actual carrier frequency offset of the RF module increases slowly with the usage time of the RF module, after compensating for the frequency offset of the first subframe of the RF operation using a preset normalized frequency offset, the first actual frequency offset value of the first subframe of the RF module is obtained, and the normalized frequency offset in the data table is updated using the first actual frequency offset value. This can partially compensate for the frequency offset increased due to the usage time of the RF module, so as to more accurately predict the actual carrier frequency offset of the first subframe within the preset time after the second startup of the RF module, thereby enabling more accurate frequency offset compensation for the first subframe within the preset time after the second startup of the RF module.

[0020] Further, the initial frequency offset value is smoothed over time using the normalized frequency offset to obtain the target frequency offset value, including: The time difference between the acquisition time of the initial frequency offset value and the acquisition time of the normalized frequency offset is obtained; The first weight corresponding to the initial frequency offset and the second weight corresponding to the normalized frequency offset are determined based on the time difference; the sum of the first weight and the second weight is equal to 1; the second weight is inversely proportional to the time difference. The target frequency offset value is obtained by performing a weighted average operation on the initial frequency offset value and the normalized frequency offset using the first weight and the second weight.

[0021] In the above implementation, weights are allocated based on the time difference. Specifically, a first weight corresponding to the initial frequency offset and a second weight corresponding to the normalized frequency offset are determined based on the time difference. Then, a weighted average is calculated using these allocated weights to perform a time-smoothing filter on the initial frequency offset, partially compensating for the frequency offset increased due to the RF module's usage time. This allows for a more accurate prediction of the actual carrier frequency offset in the first subframe within the preset time after the RF module's second startup. Consequently, frequency offset compensation can be performed more accurately in the first subframe within the preset time after the RF module's second startup.

[0022] Furthermore, frequency offset compensation is performed on subframes other than the first subframe during radio frequency operation according to a preset automatic frequency control method, including: According to the radio frequency operation sequence of each subframe, the following operations are performed sequentially on each subframe other than the first subframe in the radio frequency operation: Obtain the second actual frequency offset value and the second frequency offset compensation value of the previous subframe of this subframe; The second frequency offset compensation value is used to perform time-smoothing filtering on the second actual frequency offset value to obtain the second frequency offset compensation value of the subframe. Frequency offset compensation for this subframe is performed using the second frequency offset compensation value of this subframe.

[0023] In the above implementation, since the frequency offset of subframes other than the first subframe has become stable, frequency offset compensation can be performed using an automatic frequency control method for subframes other than the first subframe during radio frequency operation, so that the residual frequency offset of subframes other than the first subframe is stabilized within a preset threshold range.

[0024] Secondly, this application provides a carrier frequency offset compensation device based on an LTE system, wherein the LTE system includes a user terminal, a base station, and a radio frequency module for realizing wireless communication between the user terminal and the base station, and the device includes: The first compensation module is configured to perform frequency offset compensation for the first subframe of the radio frequency operation within a preset time after the radio frequency module is started, based on a preset normalized frequency offset, if radio frequency operation is performed. The normalized frequency offset is obtained by dividing the historical carrier frequency offset value by the historical carrier frequency. The historical carrier frequency offset value is obtained by measuring the carrier frequency offset in the first subframe within a preset time period after the historical radio frequency module is started. The historical carrier frequency is the carrier frequency of the historical radio frequency module. The start time of the historical radio frequency module is earlier than the start time of the radio frequency module, and the radio frequency parameters of the historical radio frequency module are the same as those of the radio frequency module. The second compensation module is configured to perform frequency offset compensation on subframes other than the first subframe in the radio frequency operation according to a preset automatic frequency control method.

[0025] Thirdly, this application provides an electronic device including a processor and a memory, wherein the memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement the carrier frequency offset compensation method based on the LTE system described in the first aspect.

[0026] Fourthly, this application provides a computer storage medium storing computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions cause the processor to implement the carrier frequency offset compensation method based on the LTE system described in the first aspect.

[0027] Fifthly, this application provides a computer program product, the computer program product including a computer program, which, when executed by a processor, is the carrier frequency offset compensation method based on the LTE system described in the first aspect. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A schematic diagram illustrating the time-varying curve of a passive crystal output reference clock provided in an embodiment of this application; Figure 2 A schematic diagram showing the carrier frequency offset of a phase-locked loop output carrier signal over time, provided in an embodiment of this application. Figure 3 A flowchart illustrating a carrier frequency offset compensation method based on an LTE system provided in this application embodiment; Figure 4 A flowchart illustrating a data table update method provided in an embodiment of this application; Figure 5 A schematic diagram of the change curve of a first weight over time provided in an embodiment of this application; Figure 6 This is a schematic diagram of the carrier frequency offset versus time curves obtained by carrier frequency offset compensation without carrier frequency offset compensation and by carrier frequency offset compensation using the carrier frequency offset compensation method provided in this application, provided as an embodiment of this application. Figure 7 This application provides a schematic diagram of the frequency offset change curve obtained when the radio frequency operation type is RX ON (gain>50dB) and the carrier frequency is 2GHz, without carrier frequency offset compensation. Figure 8 This is a schematic diagram of the frequency offset change curve of the first subframe corresponding to each RX ON (gain>50dB) operation, obtained after performing multiple RX ON (gain>50dB) operations, as provided in an embodiment of this application. Figure 9 This application provides a schematic diagram of the absolute frequency offset fluctuation curve under multiple RX ON scenarios. Figure 10 This application provides a schematic diagram of a frequency offset curve obtained by using the frequency offset value after smoothing the RX ON filter to compensate for the frequency offset of the first subframe after RX ON. Figure 11 A schematic diagram of the carrier frequency offset variation curve at a carrier frequency of 2GHz obtained by performing multiple TX ON and TX OFF operations in an embodiment of this application. Figure 12 A schematic diagram of the frequency offset variation curve of the first subframe after multiple TX ON operations, provided as an embodiment of this application; Figure 13 This application provides a schematic diagram of the frequency offset change curve obtained after frequency offset compensation of the first subframe after TX ON and TX OFF occurs using the frequency offset values ​​after smoothing the TX ON and TX OFF events, as provided in an embodiment of the present application. Figure 14 A schematic diagram of a carrier frequency offset compensation device based on an LTE system provided in this application embodiment; Figure 15 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0030] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0031] An LTE system includes user terminals, base stations, and radio frequency (RF) modules for enabling wireless communication between the user terminals and base stations. The RF modules include phase-locked loops (PLLs), local oscillators, and passive crystals.

[0032] The phase-locked loop configures its own division ratio and loop parameters based on the reference clock provided by the passive crystal, and locks the local oscillator frequency to the carrier frequency of the base station downlink signal.

[0033] User terminals can include mobile phones and computers.

[0034] When the RF module starts up, the sudden change in chip current causes the power supply voltage to drop and temperature to change. These factors cause the reference clock output by the passive crystal to deviate, which in turn causes the carrier frequency output by the phase-locked loop to deviate.

[0035] It can be calculated The transfer function of the second-order phase-locked loop (PLL) is obtained. The damping ratio can be equal to 0.707. The natural frequency is the bandwidth of the phase-locked loop.

[0036] For example, the reference clock output by a passive crystal changes due to voltage and temperature variations, such as Figure 1 In the case shown, the corresponding carrier frequency offset of the phase-locked loop output carrier signal can be as follows: Figure 2 As shown, the carrier frequency offset of the phase-locked loop output gradually stabilizes after a time greater than 1ms.

[0037] In other words, if the RF module performs RF operations within a preset time after startup, the reference clock output by the passive crystal will experience a sudden normalized frequency offset due to factors such as voltage changes. After the preset time, the normalized frequency offset will tend to stabilize. Correspondingly, the carrier signal output by the phase-locked loop will also experience a sudden carrier frequency offset, which will also tend to stabilize after the preset time.

[0038] Furthermore, this sudden carrier frequency offset can deviate by hundreds of hertz compared to the stabilized carrier frequency offset. If the historical values ​​of the natural frequency control method are still used to compensate for this sudden carrier frequency offset, since the historical values ​​of the natural frequency control method are all converged steady-state values, the deviation between them and the sudden carrier frequency offset is large. Therefore, even if the historical values ​​of the natural frequency control method are used to compensate for this sudden carrier frequency offset, a good carrier frequency offset elimination effect cannot be achieved, and the residual carrier frequency offset can still exceed the preset threshold range.

[0039] Furthermore, if the automatic frequency control method is used to track this sudden carrier frequency offset, the filtering of the automatic frequency control method has a lag, so it cannot quickly track the sudden carrier frequency offset, and therefore cannot compensate for the sudden carrier frequency offset in a timely manner.

[0040] Therefore, if the sudden normalized frequency offset and / or the sudden carrier frequency offset can be known in advance, the sudden normalized frequency offset and / or the sudden carrier frequency offset can be compensated with the opposite value, so that the carrier frequency offset of the phase-locked loop carrier signal is within the preset change threshold range.

[0041] In addition, due to the different RF parameters of the RF module, the corresponding voltage and temperature changes are different, which leads to different carrier frequency offsets generated by RF modules with different RF parameters.

[0042] Therefore, within a preset time after the historical RF module is started, the historical RF module can be controlled to perform RF operation according to different RF parameters, and the frequency offset of the first subframe of the RF operation corresponding to different RF parameters can be measured to obtain the actual carrier frequency offset value of the first subframe of the historical RF module under different RF parameters, that is, the burst carrier frequency offset.

[0043] Optionally, the radio frequency parameters include radio frequency operation type and radio frequency type. The radio frequency operation type may include one of RXON (gain>50dB), RX ON (gain<50dB), TX ON (power>20dBm), TX ON (power<20dBm), and TX OFF.

[0044] RX ON (gain > 50 dB) indicates that the RF receive mode is enabled with a gain greater than 50 dB. RX ON (gain < 50 dB) indicates that the RF receive mode is enabled with a gain less than 50 dB. TX ON (power > 20 dBm) indicates that the RF transmit mode is enabled with a transmit power greater than 20 dBm. TX ON (power < 20 dBm) indicates that the RF transmit mode is enabled with a transmit power less than 20 dBm. TX OFF indicates that RF transmit is disabled and no RF transmission occurs.

[0045] The radio frequency (RF) frequency type corresponds to the carrier frequency type, which can include low frequency, intermediate frequency (IF), and high frequency. Specifically, when the carrier frequency is greater than 0 but less than 1 GHz, the carrier frequency type is low frequency. When the carrier frequency is greater than 1 GHz but less than 2 GHz, the carrier frequency type is intermediate frequency (IF). When the carrier frequency is greater than 2 GHz, the carrier frequency type is high frequency.

[0046] Because, when the RF type is the same but the carrier frequency is different, the frequency offset of the same crystal oscillator varies proportionally to the carrier frequency on different carriers. For example, if a 24MHz crystal produces a normalized frequency offset of 24Hz (1ppm), the carrier frequency offset will be 1kHz (1ppm) on a 1GHz carrier and 2kHz (1ppm) on a 2GHz carrier.

[0047] Therefore, the normalized frequency offset for each RF parameter can be obtained by dividing the actual carrier frequency offset of the first subframe under different RF parameters of the historical RF module by the corresponding carrier frequency. This achieves the normalization of the actual carrier frequency offset of the first subframe under different RF parameters of the historical RF module, removing the influence of the carrier frequency on the actual carrier frequency offset.

[0048] Optionally, the normalized frequency offset corresponding to each RF parameter can be recorded, thereby obtaining a data table storing RF parameters, normalized frequency offset, and the correspondence between the two.

[0049] In other words, in order to compensate for the sudden carrier frequency offset of the first subframe caused by the start-up of the RF module, and to ensure that the residual carrier frequency offset after compensation is within a preset threshold range, this application constructs a correspondence between different RF parameters and sudden normalized frequency offset in advance. This allows the sudden normalized frequency offset to be used to predict the sudden carrier frequency offset of the first subframe caused by the start-up of the RF module during the use of the RF module. Then, the predicted sudden carrier frequency offset is used to compensate for the frequency offset of the first subframe of the RF module, thereby ensuring that the residual carrier frequency offset after compensation is within a preset threshold range.

[0050] Example 1 This application provides a carrier frequency offset compensation method based on an LTE system. See also... Figure 3 As shown, Figure 3 A flowchart illustrating the carrier frequency offset compensation method based on an LTE system provided in this application embodiment includes: Step S101: If an RF operation is performed within a preset time period after the RF module is started, frequency offset compensation is performed for the first subframe of the RF operation based on the preset normalized frequency offset. The normalized frequency offset is obtained by dividing the historical carrier frequency offset value by the historical carrier frequency. The historical carrier frequency offset value is the carrier frequency offset value obtained by measuring the carrier frequency offset in the first subframe within the preset time period after the historical RF module is started. The historical carrier frequency is the carrier frequency of the historical RF module. The startup time of the historical RF module is earlier than the startup time of the RF module, and the RF parameters of the historical RF module are the same as those of the RF module.

[0051] Optionally, the RF module can be activated by one of the following: turning on RF reception, turning on RF transmission, or turning off RF transmission.

[0052] Optionally, the normalized frequency offset can be obtained in the following way: the radio frequency parameters of the radio frequency module can be obtained, and then the radio frequency parameters of the radio frequency module can be used to perform a matching operation in a preset data table to obtain the normalized frequency offset.

[0053] The RF module's registers store the RF operation type and carrier frequency. Therefore, the RF operation type and carrier frequency of the RF module can be obtained from the RF module's registers. The RF operation type corresponds to the type of RF module activation: RF reception enabled, RF transmission enabled, and RF transmission disabled.

[0054] Optionally, it can be determined whether the carrier frequency value of the RF module falls within the carrier frequency range corresponding to low frequency, intermediate frequency, or high frequency, thereby determining whether the carrier frequency type of the RF module is low frequency, intermediate frequency, or high frequency. This yields the RF parameters of the RF module.

[0055] Optionally, frequency offset compensation is performed on the first subframe of the radio frequency operation according to a preset normalized frequency offset, including: determining the target frequency division ratio according to the normalized frequency offset; and controlling the radio frequency module to send the first subframe according to the target frequency division ratio.

[0056] For example, the target division ratio can be written into the register of the RF module, so that the RF module can obtain the target division ratio from the register when performing RF operations, and then send the first subframe according to the target division ratio. This can achieve frequency offset compensation at the subframe boundary and avoid phase abrupt changes caused by changing the frequency offset in the middle of the subframe.

[0057] Optionally, determining the target frequency division ratio based on the normalized frequency offset includes: obtaining the carrier frequency of the radio frequency module; multiplying the normalized frequency offset by the carrier frequency to obtain a first frequency offset compensation value; dividing the first frequency offset compensation value by a preset reference clock frequency in the radio frequency module to obtain the frequency division ratio to be adjusted; and using the frequency division ratio to be adjusted to correct the preset frequency division ratio in the radio frequency module to obtain the target frequency division ratio.

[0058] Optionally, the preset division ratio in the RF module can be corrected using the division ratio to be adjusted, including: if the frequency offset is less than the minimum value of the preset threshold range, the preset division ratio can be increased using the division ratio to be adjusted; if the frequency offset is greater than the maximum value of the preset threshold range, the preset division ratio can be decreased using the division ratio to be adjusted.

[0059] Step S102: Frequency offset compensation is performed on subframes other than the first subframe according to the preset automatic frequency control method.

[0060] Optionally, frequency offset compensation is performed on subframes other than the first subframe according to a preset automatic frequency control method, including: obtaining the second actual frequency offset value and the second frequency offset compensation value of the previous subframe of the subframe; using the second frequency offset compensation value to perform time-smoothing filtering on the second actual frequency offset value to obtain the second frequency offset compensation value of the subframe; and using the second frequency offset compensation value corresponding to the subframe to perform frequency offset compensation on the subframe.

[0061] For example, for the second subframe, the second frequency offset compensation value of the second subframe is equal to the actual frequency offset value of the first subframe. For the third subframe, the second frequency offset compensation value of the second subframe is smoothed over time using the second frequency offset compensation value of the second subframe to obtain the second frequency offset compensation value of the third subframe. This process is repeated to obtain the second frequency offset compensation values ​​for all subframes other than the first subframe.

[0062] The carrier frequency offset compensation method based on the LTE system provided in this application has a small deviation between the normalized frequency offset of the first subframe after the historical radio frequency module is activated and the normalized frequency offset of the first subframe within a preset time period after the radio frequency module is activated in this application, since the radio frequency parameters of the historical radio frequency module are the same as those of the radio frequency module. Therefore, in this application, the normalized frequency offset of the first subframe after the historical radio frequency module is activated can be regarded as the normalized frequency offset of the first subframe after the radio frequency module is activated in this application.

[0063] Meanwhile, since the historical RF module's startup time is earlier than the RF module's startup time, the carrier frequency offset can be measured in the first subframe within a preset time period after the historical RF module's startup before the RF module in this application performs RF operations. This allows for the acquisition of the historical carrier frequency offset value, which is then divided by the historical carrier frequency to obtain the normalized frequency offset of the historical RF module. This achieves the prediction of the normalized frequency offset in the first subframe after the RF module's startup before the RF module in this application performs RF operations.

[0064] Based on the normalized frequency offset of the first subframe after the RF module is started, the frequency offset of the first subframe of the RF operation can be compensated using the normalized frequency offset, so that the residual carrier frequency offset of the first subframe of the RF module in this application is within the preset threshold range.

[0065] Example 2 Figure 4 This is a flowchart illustrating the data table update method provided in an embodiment of this application. (In conjunction with...) Figure 4 As shown, the data table update method may include the following steps: Step S201: Obtain the first actual frequency offset value of the first subframe of the radio frequency module.

[0066] In one optional implementation provided in this application embodiment, obtaining the first actual frequency offset value of the first subframe of the radio frequency module includes: The user terminal obtains the time-domain location of the CRS reference signal through signaling. For example, the time-domain location of the CRS reference signal is at the time-frequency location of symbol 0 and symbol 4.

[0067] Upon receiving the first subframe, the user terminal extracts the CRS reference signal from different time-domain locations within the first subframe. For example, the received CRS reference signal is extracted at the time-frequency locations of symbols 0 and 4 in the first subframe.

[0068] Then, for each time-domain CRS reference signal, the phase difference between the received CRS reference signal and the pre-stored CRS reference signal at the corresponding time-domain location is calculated.

[0069] Then, the phase difference value between the phase differences corresponding to the two time domain positions can be obtained, and the rate of change of phase over time can be obtained using the phase difference value and the time interval between the two time domain positions, thereby obtaining the actual frequency offset value of the first subframe.

[0070] For example, a first phase difference p0 can be calculated between the CRS reference signal of symbol 0 and the corresponding CRS reference signal of symbol 0 stored locally. A second phase difference p4 can also be calculated between the CRS reference signal of symbol 4 and the corresponding CRS reference signal of symbol 4 stored locally.

[0071] Then, the phase difference between the first phase difference p0 and the second phase difference p4 is calculated. For example, the phase difference between the first phase difference p0 and the second phase difference p4 can be obtained by calculating delta_p = p4 - p0. Here, delta_p represents the difference between the two phase differences.

[0072] Then, the time interval between symbol 0 and symbol 4 can be obtained. Finally, the first actual frequency offset value of the first subframe is obtained by calculating delta f = delta_p / (2*π*delta_t). Here, delta_t represents the time interval between symbol 0 and symbol 4, and π represents pi. In this way, radians can be converted into periods, thus obtaining the first actual frequency offset value.

[0073] Step S202: Update the normalized frequency offset in the data table according to the first actual frequency offset value.

[0074] In one optional implementation of this application, if the normalized frequency offset in the data table is 0, the normalized frequency offset in the data table is updated according to the first actual frequency offset value, including: dividing the first actual frequency offset value by the carrier frequency to obtain the initial frequency offset value; and replacing the normalized frequency offset in the data table with the initial frequency offset value.

[0075] In another optional implementation of this application, if the data table does not have a normalized frequency offset corresponding to the radio frequency parameters of the radio frequency module of this application, the normalized frequency offset in the data table is updated according to the first actual frequency offset value, including: dividing the first actual frequency offset value by the carrier frequency to obtain an initial frequency offset value; recording the correspondence between the initial frequency offset value and the radio frequency parameters of the radio frequency module in the data table, wherein the initial frequency offset value is the normalized frequency offset.

[0076] In another optional implementation of this application, updating the normalized frequency offset in the data table according to the first actual frequency offset value includes: dividing the first actual frequency offset value by the carrier frequency to obtain an initial frequency offset value; performing time-smoothing filtering on the initial frequency offset value using the normalized frequency offset to obtain a target frequency offset value; and replacing the normalized frequency offset in the data table with the target frequency offset value.

[0077] Optionally, the initial frequency offset value is smoothed over time using a normalized frequency offset to obtain the target frequency offset value. This includes: obtaining the time difference between the acquisition time of the initial frequency offset value and the acquisition time of the normalized frequency offset; determining the first weight corresponding to the initial frequency offset value and the second weight corresponding to the normalized frequency offset based on the time difference; the sum of the first weight and the second weight equals 1; the second weight is inversely proportional to the time difference; and performing a weighted average calculation on the initial frequency offset value and the normalized frequency offset using the first weight and the second weight to obtain the target frequency offset value.

[0078] In some embodiments, the first weight can be obtained by calculating α = max(0.5, 0.9 - delta_ms / 300). Here, delta_ms represents the time difference between the acquisition time of the initial frequency offset value and the acquisition time of the normalized frequency offset. The trend of α over time can be as follows: Figure 5 As shown.

[0079] Optionally, it can be calculated Obtain the target frequency offset value. Among them, f (n-1) The normalized frequency offset corresponding to the RF parameters of the RF module of this application in the data table is used to characterize the RF parameters. f n Characterizes the initial frequency offset value.

[0080] like f The noise variance is σ 2As the number of updates increases, the variance converges to the following steady-state value:

[0081] When α equals 0.9, the updated weights focus on historical values, and the steady-state variance is approximately 0.05. σ 2 It is suitable for convergence of frequency offset values ​​in fixed scenarios.

[0082] The data table update method provided in this application obtains the first actual frequency offset value of the first subframe of the radio frequency module and updates the normalized frequency offset in the data table using the first actual frequency offset value. This ensures that the normalized frequency offset stored in the data table is the most recently measured normalized frequency offset, reducing the impact of time factors on the normalized frequency offset. This allows for a more accurate prediction of the actual carrier frequency offset of the first subframe within a preset time after the second startup of the radio frequency module, thereby enabling more accurate frequency offset compensation for the first subframe within the preset time after the second startup of the radio frequency module.

[0083] Example 3 This embodiment is used to verify the carrier frequency offset compensation method based on the LTE system provided in the above embodiment.

[0084] If the RF module's RF operation type is RX ON (gain > 50dB) and the carrier frequency is 2GHz, then... Figure 6 As shown, Figure 6 The horizontal axis represents the subframes already transmitted by the RF module, and the vertical axis represents the frequency offset. Freq00 represents the frequency offset of the received signal at the second symbol in the corresponding subframe. Figure 6 The blue dot in the image. Freq01 represents the frequency offset of the received signal at the 9th symbol in the corresponding subframe. Figure 6 The red dot in the image. According to... Figure 6 As shown by the solid black line, when the RF module turns on the receiver module, i.e., before the RX ON (gain > 50dB) operation (corresponding to the first subframe 7 on the horizontal axis), the frequency offset of the PLL carrier signal has already stabilized near 0Hz under AFC tracking (corresponding to subframe 1 on the horizontal axis; the blue and red dots in subframe 1 are almost overlapping and close to 0). In the first subframe after the RX ON operation (corresponding to subframe 7 on the horizontal axis), the frequency offset of the PLL carrier signal shifts positively from -150Hz in symbol 2 to -50Hz in symbol 9 (indicated by the arrow), with an average frequency offset of -100Hz. This offset converges in the second subframe (corresponding to subframe 8 on the horizontal axis) and thereafter, stabilizing within approximately + / -20Hz. If the frequency offset value already converged by the previous AFC method is used, the sudden frequency offset in the first subframe cannot be compensated, thus affecting the signal quality of the first subframe.

[0085] Figure 6 The solid green line in the graph represents the curve of the average frequency offset of the RF module changing over time after the RF module turns on the receiver module, i.e., after the RX ON (gain>50dB) operation is performed.

[0086] However, according to the carrier frequency offset compensation method based on the LTE system provided in this application embodiment, the normalized frequency offset corresponding to the radio frequency parameter RX ON (gain>50dB) is obtained from the data table, and frequency offset compensation is performed on the first subframe of the radio frequency operation using this normalized frequency offset. Simultaneously, frequency offset compensation is performed on subframes other than the first subframe in the radio frequency operation according to the Automatic Frequency Control (AFC) method, and the resulting effect is as follows: Figure 6 As shown by the dashed line, the carrier frequency offset compensation method provided in this application can stabilize the frequency offset of the entire received signal within a preset threshold range by compensating for the frequency offset of the RF module. This reduces the impact of RX ON operation and improves the signal quality of the first subframe.

[0087] Alternatively, from Figure 6 Extracting the frequency offset changes of the two subframes after the RX ON operation (corresponding to the first subframe 7 and the second subframe 8) from the black solid line yields the following: Figure 7 The frequency offset variation curve shown is shown. Figure 7 The vertical axis represents the frequency offset value, along Figure 7 The horizontal axis, from left to right, shows the following: the first blue dot represents the average frequency offset of symbol 2 in the first subframe; the first red dot represents the average frequency offset of symbol 9 in the second subframe; the second blue dot represents the average frequency offset of symbol 2 in the second subframe; and the second red dot represents the average frequency offset of symbol 9 in the second subframe. It can be seen that... Figure 7 The frequency offset variation curve shown is Figure 2 The carrier frequency offset curves shown are similar, with the frequency offset being the largest in the first subframe and then gradually stabilizing. Therefore, special compensation can be performed for the first subframe (corresponding to frequency offset compensation for the first subframe of RF operation based on the preset normalized frequency offset).

[0088] If the RF module's RF operation type is RX ON (gain>50dB), multiple RX ON (gain>50dB) operations can be performed on the same RF module, i.e., multiple times turning the RF receiver on and off, with the gain set to be greater than 50dB. Then, within a preset time period after each RX ON (gain>50dB) operation, the frequency offset change of the first subframe is collected to obtain... Figure 8 The frequency offset variation curve shown is shown.

[0089] exist Figure 8In the frequency offset variation curve shown, each diagonal line represents the carrier frequency offset measured in subframe 1 or 6 after an RX ON operation (the blue endpoint represents the carrier frequency offset measured at time-frequency position symbol 2, and the red endpoint represents the carrier frequency offset measured at time-frequency position symbol 9). It can be seen that although the average carrier frequency offset changes slowly, the trend of carrier frequency offset change is consistent, conforming to the theoretical prediction trend. That is, under the same RF operation and the same gain conditions, the carrier frequency offset caused by the RF operation is regular. Although it changes with temperature, aging, and fluctuations in the normalized frequency offset itself, the first two change slowly and can be tracked through data table updates, while smoothing filtering also suppresses fluctuations in the normalized frequency offset itself.

[0090] Combination Figure 9 The graph shows the absolute frequency offset fluctuation curves under multiple RX ON scenarios. The timing of the RX ON operation corresponds to... Figure 9 The yellow dashed line in the middle. Figure 9 The green dashed line in the graph represents the curve of the average frequency offset changing over time. Figure 9 The black solid line in the figure represents the actual carrier frequency offset of the RF module after the RX ON operation.

[0091] As can be seen, the average frequency offset is distinctly sawtooth-shaped. After RX ON, the carrier frequency offset curve gradually rises and tends to stabilize. Figure 9 The purple solid line in the curve represents the carrier frequency offset value after smoothing filtering of the first subframe after RX ON (ppm has been converted to Hz). This curve can be used to filter out noise fluctuations and stably track the carrier frequency offset trend over time.

[0092] If the frequency offset value after RX ON smoothing is used to compensate for the first subframe after RX ON, and the AFC system is only responsible for tracking the stabilized frequency offset, then the hyperbolic compensation mode can be used to compensate for continuous RX ON scenes. The obtained frequency offset compensation result is as follows: Figure 10 As shown. Figure 10 The purple dashed line in the image represents the frequency offset of subframes other than the first subframe after RX ON using AFC tracking. It can be seen that the frequency offset of subframes other than the first subframe after RX ON tends to stabilize. Figure 10 The red solid line represents the frequency offset value after RX ON smoothing filtering (ppm has been converted to Hz), used to compensate for the first subframe after RX ON. The compensation result is represented by a wavy line on the horizontal axis (green wavy line). It can be seen that the compensated frequency offset value remains within + / -20Hz, that is, within the preset threshold range, thus avoiding the phenomenon of decreased received signal quality caused by sudden frequency offset changes in the first subframe after RX ON.

[0093] Example 4 This embodiment is used to verify the carrier frequency offset compensation method based on the LTE system provided in the above embodiment.

[0094] For TX ON (power > 20 dBm) and TX OFF scenarios Combination Figure 11 As shown, with the RF receiver mode of the RF module enabled, continuously performing TX ON and TX OFF operations can obtain the carrier frequency offset change of the RF module at a carrier frequency of 2GHz (green solid line).

[0095] It is evident that the TX ON operation can cause a sudden increase in the frequency deviation trend, while the TX OFF operation can cause a sudden decrease in the frequency deviation curve. Therefore, the change trend exhibits obvious pulse-like abrupt changes with the TX ON and TX OFF operations.

[0096] Will Figure 11 The frequency offset change of the first subframe after the TX ON operation is extracted, and the following can be obtained: Figure 12 The frequency offset curve shown is a graph. Figure 12 In the diagram, each yellow vertical line represents a single TX ON, the arrows indicate the direction of frequency offset change within a subframe, and the green solid line represents the trend of the average frequency offset after filtering. It can be seen that the frequency offset changes caused by TX ON at different times are similar, with only fluctuations in the frequency offset of the PLL output clock itself and slow changes with temperature. Therefore, the average frequency offset of TX ON after smoothing filtering can filter out noise fluctuations and track the trend of temperature changes.

[0097] The average frequency offset of TX ON after smoothing filtering (corresponding to) Figure 13 The green dashed line in the image) and the average frequency offset curve of TX OFF after smoothing filtering (corresponding to...) Figure 13 The red dashed line (in the diagram) is used to compensate for the frequency offset of the first subframe after TX ON and TX OFF occur, and AFC is used to track the frequency offset of the remaining relatively stable subframes. This can be achieved as follows: Figure 13 As shown by the solid black line, the frequency offset no longer exhibits sudden pulse changes, but converges within the range of + / -20Hz. Therefore, the impact of the frequency offset caused by the TX ON / OFF operation on the received signal can be minimized.

[0098] Example 5: Based on the same inventive concept, this application also provides a carrier frequency offset compensation device 400 based on an LTE system. Please refer to... Figure 14 As shown, Figure 14 It shows the use of Figure 3The illustrated method is a carrier frequency offset compensation device based on an LTE system. It should be understood that the specific functions of device 400 are described above; to avoid repetition, detailed descriptions are omitted here. Device 400 includes at least one software function module that can be stored in memory or embedded in the operating system of device 400 in the form of software or firmware. Specifically: See Figure 14 As shown, the carrier frequency offset compensation device 400 based on the LTE system is applied to a user terminal and includes: a first compensation module 401 and a second compensation module 402. Wherein: The first compensation module 401 is configured to perform frequency offset compensation for the first subframe of the radio frequency operation within a preset time after the radio frequency module is started, if radio frequency operation is performed, based on the preset normalized frequency offset. The normalized frequency offset is obtained by dividing the historical carrier frequency offset value by the historical carrier frequency. The historical carrier frequency offset value is obtained by measuring the carrier frequency offset in the first subframe within a preset time after the historical RF module is started. The historical carrier frequency is the carrier frequency of the historical RF module. The start time of the historical RF module is earlier than the start time of the RF module, and the RF parameters of the historical RF module are the same as those of the RF module. The second compensation module 402 is configured to perform frequency offset compensation on subframes other than the first subframe in the radio frequency operation according to a preset automatic frequency control method.

[0099] In one feasible embodiment of this application, the first compensation module 401 may be specifically configured to determine the target frequency division ratio based on the normalized frequency offset and control the radio frequency module to send the first subframe according to the target frequency division ratio.

[0100] In one feasible embodiment of this application, the first compensation module 401 may be specifically configured to: obtain the carrier frequency of the radio frequency module; multiply the normalized frequency offset by the carrier frequency to obtain a first frequency offset compensation value; divide the first frequency offset compensation value by the preset reference clock frequency in the radio frequency module to obtain the frequency division ratio to be adjusted; and use the frequency division ratio to be adjusted to correct the preset frequency division ratio in the radio frequency module to obtain the target frequency division ratio.

[0101] In one feasible embodiment of this application, the first compensation module 401 can also be configured to acquire the radio frequency parameters of the radio frequency module, the radio frequency parameters including the radio frequency operation type and the carrier frequency type; in a preset data table, the radio frequency parameters are used to perform a matching operation to obtain the normalized frequency offset; the data table stores the radio frequency parameters, the normalized frequency offset and the correspondence between the two.

[0102] In one feasible embodiment of this application, the carrier frequency offset compensation device 400 based on the LTE system may further include an update module, configured to obtain the first actual frequency offset value of the first subframe of the radio frequency module; and update the normalized frequency offset in the data table according to the first actual frequency offset value.

[0103] In one feasible embodiment of this application, the update module can be specifically configured to obtain an initial frequency offset value by dividing the first actual frequency offset value by the carrier frequency; to perform time-smoothing filtering on the initial frequency offset value using normalized frequency offset to obtain a target frequency offset value; and to replace the normalized frequency offset in the data table with the target frequency offset value.

[0104] In one feasible embodiment of this application, the update module can be specifically configured to obtain the time difference between the acquisition time of the initial frequency offset value and the acquisition time of the normalized frequency offset; determine the first weight corresponding to the initial frequency offset value and the second weight corresponding to the normalized frequency offset based on the time difference; the sum of the first weight and the second weight is equal to 1; the second weight is inversely proportional to the time difference; and perform a weighted average operation on the initial frequency offset value and the normalized frequency offset using the first weight and the second weight to obtain the target frequency offset value.

[0105] In one feasible embodiment of this application, the second compensation module 402 may be specifically configured to perform the following operations on each subframe other than the first subframe in the radio frequency operation according to the radio frequency operation order of each subframe: obtain the second actual frequency offset value and the second frequency offset compensation value of the previous subframe of the subframe; use the second frequency offset compensation value to perform time smoothing filtering on the second actual frequency offset value to obtain the second frequency offset compensation value of the subframe; and use the second frequency offset compensation value of the subframe to perform frequency offset compensation on the subframe.

[0106] It should be understood that, for the sake of brevity, some of the content described in Embodiment 1 will not be repeated in this embodiment.

[0107] Example 6: Based on the same inventive concept, this embodiment provides an electronic device, see [link to relevant documentation]. Figure 15 As shown, it includes a processor 501 and a memory 502. Wherein: The processor 501 is used to execute one or more programs stored in the memory 502 to implement the above-described carrier frequency offset compensation method based on the LTE system.

[0108] It is understandable that processor 501 can be a processor core or processor chip, or other circuitry capable of program configuration and execution. Memory 502 can be RAM (Random Access Memory), ROM (Read-Only Memory), flash memory, etc., but this is not a limitation.

[0109] It's understandable. Figure 15 The structure shown is for illustrative purposes only; the electronic device may also include components that are more advanced than those shown. Figure 15 The more or fewer components shown, or having the same Figure 15 Different configurations are shown. For example, it may also have an internal communication bus 503 for communication between the processor 501 and the memory 502; or it may have an external communication interface, such as a USB (Universal Serial Bus) interface, a CAN (Controller Area Network) bus interface, etc.; or it may have an information display component such as a display screen, but this is not a limitation.

[0110] In this application, the electronic device can be a user terminal.

[0111] Based on the same inventive concept, this embodiment also provides a computer-readable storage medium, such as a floppy disk, optical disk, hard disk, flash memory, USB flash drive, SD (Secure Digital Memory Card), MMC (Multimedia Card), etc., in which one or more programs implementing the above steps are stored. These one or more programs can be executed by one or more processors to implement the above-described carrier frequency offset compensation method based on the LTE system. Further details will not be elaborated here.

[0112] Based on the same inventive concept, this embodiment also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described carrier frequency offset compensation method based on an LTE system.

[0113] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0114] Furthermore, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0115] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0116] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0117] In this article, "multiple" refers to two or more.

[0118] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A carrier frequency offset compensation method based on an LTE system, characterized in that, The LTE system includes a user terminal, a base station, and a radio frequency module for enabling wireless communication between the user terminal and the base station. The method includes: If an RF operation is performed within a preset time after the RF module is started, frequency offset compensation will be performed for the first subframe of the RF operation based on the preset normalized frequency offset. The normalized frequency offset is obtained by dividing the historical carrier frequency offset value by the historical carrier frequency. The historical carrier frequency offset value is obtained by measuring the carrier frequency offset in the first subframe within a preset time period after the historical radio frequency module is started. The historical carrier frequency is the carrier frequency of the historical radio frequency module. The start time of the historical radio frequency module is earlier than the start time of the radio frequency module, and the radio frequency parameters of the historical radio frequency module are the same as those of the radio frequency module. Frequency offset compensation is performed on subframes other than the first subframe in the radio frequency operation according to the preset automatic frequency control method.

2. The method according to claim 1, characterized in that, Frequency offset compensation is performed on the first subframe of the RF operation based on the preset normalized frequency offset, including: The target frequency division ratio is determined based on the normalized frequency offset. The radio frequency module is controlled to transmit the first subframe according to the target frequency division ratio.

3. The method according to claim 2, characterized in that, Determining the target frequency division ratio based on the normalized frequency offset includes: Obtain the carrier frequency of the radio frequency module; The first frequency offset compensation value is obtained by multiplying the normalized frequency offset by the carrier frequency; The frequency division ratio to be adjusted is obtained by dividing the first frequency offset compensation value by the preset reference clock frequency in the radio frequency module. The preset division ratio in the radio frequency module is corrected using the division ratio to be adjusted to obtain the target division ratio.

4. The method according to claim 1, characterized in that, Before performing frequency offset compensation for the first subframe of the RF operation based on the preset normalized frequency offset, the following steps are also included: Obtain the radio frequency parameters of the radio frequency module, including the radio frequency operation type and carrier frequency type; In a preset data table, the radio frequency parameters are used to perform a matching operation to obtain the normalized frequency offset; the data table stores the radio frequency parameters, the normalized frequency offset, and the correspondence between the two.

5. The method according to claim 4, characterized in that, Also includes: Obtain the first actual frequency offset value of the first subframe of the radio frequency module; The normalized frequency offset in the data table is updated based on the first actual frequency offset value.

6. The method according to claim 5, characterized in that, Updating the normalized frequency offset based on the first actual frequency offset value includes: The initial frequency offset value is obtained by dividing the first actual frequency offset value by the carrier frequency; The initial frequency offset value is smoothed over time using the normalized frequency offset to obtain the target frequency offset value. Replace the normalized frequency offset in the data table with the target frequency offset value.

7. The method according to claim 6, characterized in that, The target frequency offset value is obtained by performing time-smoothing filtering on the initial frequency offset value using the normalized frequency offset, including: The time difference between the acquisition time of the initial frequency offset value and the acquisition time of the normalized frequency offset is obtained; The first weight corresponding to the initial frequency offset and the second weight corresponding to the normalized frequency offset are determined based on the time difference; the sum of the first weight and the second weight is equal to 1; the second weight is inversely proportional to the time difference. The target frequency offset value is obtained by performing a weighted average operation on the initial frequency offset value and the normalized frequency offset using the first weight and the second weight.

8. The method according to any one of claims 1 to 7, characterized in that, Frequency offset compensation is performed on subframes other than the first subframe during radio frequency operation according to a preset automatic frequency control method, including: According to the radio frequency operation sequence of each subframe, the following operations are performed sequentially on each subframe other than the first subframe in the radio frequency operation: Obtain the second actual frequency offset value and the second frequency offset compensation value of the previous subframe of this subframe; The second frequency offset compensation value is used to perform time-smoothing filtering on the second actual frequency offset value to obtain the second frequency offset compensation value of the subframe. Frequency offset compensation for this subframe is performed using the second frequency offset compensation value of this subframe.

9. A carrier frequency offset compensation device based on an LTE system, characterized in that, The LTE system includes a user terminal, a base station, and a radio frequency module for enabling wireless communication between the user terminal and the base station. The device includes: The first compensation module is configured to perform frequency offset compensation for the first subframe of the radio frequency operation within a preset time after the radio frequency module is started, based on a preset normalized frequency offset, if radio frequency operation is performed. The normalized frequency offset is obtained by dividing the historical carrier frequency offset value by the historical carrier frequency. The historical carrier frequency offset value is obtained by measuring the carrier frequency offset in the first subframe within a preset time period after the historical radio frequency module is started. The historical carrier frequency is the carrier frequency of the historical radio frequency module. The start time of the historical radio frequency module is earlier than the start time of the radio frequency module, and the radio frequency parameters of the historical radio frequency module are the same as those of the radio frequency module. The second compensation module is configured to perform frequency offset compensation on subframes other than the first subframe in the radio frequency operation according to a preset automatic frequency control method.

10. An electronic device, characterized in that, The system includes a processor and a memory, the memory storing computer-executable instructions that can be executed by the processor, the processor executing the computer-executable instructions to implement the carrier frequency offset compensation method based on an LTE system as described in any one of claims 1 to 8.

11. A computer storage medium, characterized in that, The storage medium stores computer-executable instructions, which, when called and executed by a processor, cause the processor to implement the carrier frequency offset compensation method based on the LTE system as described in any one of claims 1 to 8.

12. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the carrier frequency offset compensation method based on the LTE system as described in any one of claims 1 to 8.

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