DC offset determination method, apparatus, electronic equipment and storage medium

Abstract

This application relates to the field of communication technology and provides a method, apparatus, electronic device, and storage medium for determining DC offset. The method involves acquiring uplink time-domain received symbols containing a demodulation reference signal and performing a frequency-domain transformation on these symbols to obtain corresponding frequency-domain received information. Using a reference frequency point in the transformed frequency-domain received information as a reference, multiple target subcarriers close to the reference frequency point are selected. Based on the frequency-domain received information corresponding to each target subcarrier, a parameterized model characterizing the correspondence between the DC offset and the frequency-domain received information is established. The DC offset is determined according to the parameterized model. By performing a frequency-domain transformation on the uplink time-domain received symbols containing the demodulation reference signal and using the reference frequency point in the frequency-domain received information as a reference, only multiple target subcarriers close to the reference frequency point are selected for analysis, making the DC offset information more concentrated, the effective signal-to-noise ratio higher, and improving the accuracy of the acquired DC offset.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a method, apparatus, electronic device and storage medium for determining DC offset. Background Technology

[0002] With the development of mobile communication technology, Long Term Evolution (LTE) systems have been widely used in mobile broadband communication. In the LTE uplink, the terminal equipment (UE) uses single-carrier frequency division multiple access (SC-FDMA) technology for signal transmission. This technology essentially uses a combination of Discrete Fourier Transform (DFT) and Inverse Fast Fourier Transform (IFFT) at the transmitting end to generate time-domain signals through multi-carrier modulation. The receiving end needs to convert the time-domain signal into a frequency-domain signal for demodulation.

[0003] In practical systems, due to hardware non-ideal factors such as RF link imbalance, analog-to-digital converter bias, power supply noise, and local oscillator leakage, a DC offset is usually introduced into the received signal. This DC offset manifests as a fixed or slowly varying DC component superimposed on the time-domain signal. After FFT transformation, the DC component not only generates an energy peak at zero frequency but also leaks on several nearby subcarriers, thus affecting the spectral characteristics of the received signal.

[0004] If the DC offset cannot be accurately estimated and compensated, the following problems will occur: amplitude and phase distortion of the frequency domain signal at zero frequency and adjacent subcarriers will occur, affecting the accuracy of channel estimation and data demodulation; in the uplink, the synchronization detection, channel estimation and signal-to-noise ratio calculation during base station demodulation may be affected by the DC component, resulting in a decrease in system performance.

[0005] In existing technologies, DC offset is usually estimated by calculating a simple average value of the received signal in the time domain. However, this method is easily affected by factors such as subcarrier leakage, resulting in limited estimation accuracy. Summary of the Invention

[0006] In view of this, embodiments of this application provide a method, apparatus, electronic device, and storage medium for determining DC offset, in order to solve the problem that the DC offset cannot be accurately obtained in the prior art.

[0007] A first aspect of this application provides a method for determining DC offset. The method includes: acquiring uplink time-domain received symbols containing a demodulated reference signal, and performing frequency-domain transformation on the uplink time-domain received symbols to obtain corresponding frequency-domain received information; selecting multiple target subcarriers close to the reference frequency point from the transformed frequency-domain received information as a reference; establishing a parameterized model characterizing the correspondence between DC offset and frequency-domain received information based on the frequency-domain received information corresponding to each target subcarrier; and determining the DC offset according to the parameterized model.

[0008] A second aspect of this application provides a DC offset determination apparatus, comprising: an acquisition module, configured to acquire uplink time-domain received symbols containing a demodulated reference signal, and perform frequency-domain transformation on the uplink time-domain received symbols to obtain corresponding frequency-domain received information; a selection module, configured to select multiple target subcarriers close to the reference frequency point from the transformed frequency-domain received information as a reference; and a model module, configured to establish a parameterized model characterizing the correspondence between the DC offset and the frequency-domain received information based on the frequency-domain received information corresponding to each target subcarrier; and determine the DC offset according to the parameterized model.

[0009] A third aspect of this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described method.

[0010] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the above-described method.

[0011] The beneficial effects of this application embodiment compared with the prior art are as follows: The method in this application embodiment obtains uplink time-domain received symbols containing demodulation reference signals, and performs frequency-domain transformation on the uplink time-domain received symbols to obtain corresponding frequency-domain received information; using the reference frequency point in the transformed frequency-domain received information as a reference, multiple target subcarriers close to the reference frequency point are selected; based on the frequency-domain received information corresponding to each target subcarrier, a parameterized model characterizing the correspondence between DC offset and frequency-domain received information is established; the DC offset is determined according to the parameterized model; this application obtains uplink time-domain received symbols containing demodulation reference signals, and performs frequency-domain transformation on the uplink time-domain received symbols to obtain corresponding frequency-domain received information; using the reference frequency point in the transformed frequency-domain received information as a reference, multiple target subcarriers close to the reference frequency point are selected; based on the frequency-domain received information corresponding to each target subcarrier, a parameterized model characterizing the correspondence between DC offset and frequency-domain received information is established; based on the parameterized model, the DC offset is determined; this application obtains uplink time-domain received symbols containing demodulation reference signals, and performs frequency-domain transformation on the uplink time-domain received symbols to obtain corresponding frequency-domain received information ... The uplink time-domain received symbols of the test signal are transformed in the frequency domain, so that the mixed DC components in the time domain are concentrated in the frequency domain to the zero frequency and its neighboring subcarriers, which facilitates identification and modeling. Based on the reference frequency point in the frequency domain received information, only multiple target subcarriers close to the reference frequency point are selected for analysis, making the DC offset information more concentrated and the effective signal-to-noise ratio higher. A parameterized model representing the DC offset and the frequency domain received information is jointly established based on the selected target subcarriers, and the DC offset is obtained from this model, which improves the accuracy of the obtained DC offset and avoids the problem of not being able to accurately obtain the DC offset in the existing technology. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a flowchart illustrating a DC offset determination method provided in an embodiment of this application;

[0014] Figure 2 This is a schematic diagram of a typical structure of an LTE uplink time-domain receive symbol provided in an embodiment of this application;

[0015] Figure 3 This is a schematic diagram of an embodiment of the present application where all 12 target subcarriers are empty subcarriers;

[0016] Figure 4 This is a schematic diagram of another embodiment of the present application where all 12 target subcarriers are empty subcarriers;

[0017] Figure 5 This is a schematic diagram of an embodiment of the present application where all 12 target subcarriers are DM-RS subcarriers;

[0018] Figure 6 This is a target subcarrier provided in the embodiments of this application. For DM-RS subcarriers, target subcarriers A schematic diagram of an empty subcarrier;

[0019] Figure 7 This is a target subcarrier provided in the embodiments of this application. empty subcarrier, target subcarrier A schematic diagram of a DM-RS subcarrier;

[0020] Figure 8 This is a schematic diagram of the structure of a DC offset determination device provided in an embodiment of this application;

[0021] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0022] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0023] A method and apparatus for determining DC offset according to an embodiment of this application will now be described in detail with reference to the accompanying drawings.

[0024] Figure 1 This is a flowchart illustrating a DC offset determination method provided in an embodiment of this application, as shown below. Figure 1 As shown, the method includes:

[0025] S101. Obtain the uplink time-domain received symbol containing the demodulation reference signal (DM-RS), and perform frequency domain transformation on the uplink time-domain received symbol to obtain the corresponding frequency domain received information.

[0026] S102. Using the reference frequency point in the frequency domain received information obtained by transformation as a reference, select multiple target subcarriers that are close to the reference frequency point.

[0027] S103. Based on the frequency domain received information corresponding to each target subcarrier, establish a parameterized model representing the correspondence between DC offset and frequency domain received information;

[0028] S104. Determine the DC offset based on the parametric model.

[0029] like Figure 2 As shown, Figure 2This is a typical structure for LTE uplink time-domain receive symbols. Along the time domain direction, each time slot contains 7 consecutive uplink time-domain receive symbols, with the middle uplink time-domain receive symbol containing a DM-RS subcarrier. The DM-RS subcarrier carries a reference sequence known to the receiver, used for system synchronization and channel estimation.

[0030] This application first acquires the uplink time-domain received symbols containing the demodulation reference signal, and then performs a frequency-domain transformation on the uplink time-domain received symbols to obtain the corresponding frequency-domain received information. Specifically, in the uplink time-domain received symbols containing DM-RS subcarriers, the cyclic prefix (CP) is first removed; then, an FFT (Fast Fourier Transform) window is used to truncate the time-domain signal after removing the CP, resulting in a length of... Uplink time domain received signal Next, regarding Half a subcarrier frequency shift compensation is performed to offset the 0.5 times subcarrier frequency offset introduced by the transmitter when generating the baseband signal; subsequently, the compensated signal... A frequency domain transformation is performed to convert the uplink time-domain received signal into frequency-domain received information. This frequency domain transformation can be implemented using a Fast Fourier Transform (FFT) or its equivalent, the Discrete Fourier Transform (DFT). Finally, based on the obtained frequency-domain received information, the DC offset is estimated.

[0031] In some examples, this application uses a reference frequency point in the transformed frequency domain received information as a reference, and selects multiple target subcarriers close to the reference frequency point. For example, using the reference frequency point in the transformed frequency domain received information as a reference, the six subcarriers before the reference frequency point, the subcarrier containing the reference frequency point, and the five subcarriers after the reference frequency point are selected as target subcarriers. In other examples, the number of target subcarriers may be determined based on system bandwidth, noise level, or FFT length. The selection criteria can be adjusted accordingly. For example, 10 subcarriers close to the reference frequency can be selected as target subcarriers (subcarriers -5, -4, ..., -1, 0, 1, ..., 4), 8 subcarriers can be selected as target subcarriers (subcarriers -4, -3, -2, -1, 0, 1, 2, 3), 6 subcarriers can be selected as target subcarriers (subcarriers -3, -2, -1, 0, 1, 2), or more subcarriers (such as 14 or 16 subcarriers) can be selected as target subcarriers.

[0032] After acquiring multiple target subcarriers, this application will establish a parameterized model representing the correspondence between DC offset and frequency domain received information based on the frequency domain received information corresponding to each target subcarrier; and determine the DC offset based on the parameterized model.

[0033] Specifically, based on the frequency domain received information corresponding to the target subcarrier, a parameterized model characterizing the correspondence between the DC offset and the frequency domain received information is established, including:

[0034] Obtain the pre-set original parameterized model, and substitute the frequency domain received information corresponding to each target subcarrier into the original parameterized model to establish the parameterized model; the original parameterized model is represented as:

[0035] ;

[0036] in, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates the first Channel response corresponding to each target subcarrier Indicates the first The modulation symbols carried by each target subcarrier This represents the DC offset (which is an unknown parameter to be solved). Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The noise corresponding to each target subcarrier.

[0037] It is understandable that, because carrier frequency synchronization is typically performed before DC offset estimation, the residual carrier frequency offset is small, for example, no more than 1% of the subcarrier spacing, and will not introduce significant inter-subcarrier crosstalk in the frequency domain. In this case, in the time-domain symbol containing the DM-RS subcarriers, the frequency-domain received information on each subcarrier can be approximately expressed as the linear relationship described above ( ).

[0038] in, The calculation formula is as follows:

[0039] ;

[0040] When the FFT transforms to a power-normalized form (i.e., the signal power remains the same before and after the transformation), the above formula also needs to be divided by... .

[0041] Using the properties of geometric series and trigonometric functions, we can... The calculation formula is simplified to

[0042] ;

[0043] in, The function represents the cotangent function, which is the reciprocal of the tangent function. Similarly, if the FFT transform is in a power-normalized form (i.e., the signal power remains the same before and after the transform), the simplified formula also needs to be divided by... .

[0044] To reduce the complexity of real-time computation and avoid loss of numerical precision, It can be pre-calculated and stored as a look-up table (LUT) during the system design or initialization phase, and then directly called by looking up the table during subsequent processing.

[0045] By substituting the frequency domain received information of multiple target subcarriers into the original parameterized model described above, a parameterized model containing multiple equations can be obtained. Based on this parameterized model, unknown parameters can be... The solution is performed to obtain the DC offset, thereby achieving an accurate estimation of the DC component in the received signal.

[0046] According to the technical solution provided in the embodiments of this application, uplink time-domain received symbols containing demodulation reference signals are obtained, and frequency-domain transformed on the uplink time-domain received symbols to obtain corresponding frequency-domain received information; using the reference frequency point in the transformed frequency-domain received information as a reference, multiple target subcarriers close to the reference frequency point are selected; based on the frequency-domain received information corresponding to each target subcarrier, a parameterized model characterizing the correspondence between DC offset and frequency-domain received information is established; the DC offset is determined according to the parameterized model; this application performs frequency-domain transformation on uplink time-domain received symbols containing demodulation reference signals, so that the mixed DC components in the time domain are concentrated to zero frequency and its neighboring subcarriers in the frequency domain, thereby facilitating identification and modeling; using the reference frequency point in the frequency-domain received information as a reference, only multiple target subcarriers close to the reference frequency point are selected for analysis, making the DC offset information more concentrated and the effective signal-to-noise ratio higher; a parameterized model characterizing DC offset and frequency-domain received information is jointly established based on the selected target subcarriers, and the DC offset is obtained accordingly, improving the accuracy of the obtained DC offset and avoiding the problem of inaccurate DC offset acquisition in the prior art.

[0047] Taking the six subcarriers before the reference frequency, the subcarrier at the reference frequency, and the five subcarriers after the reference frequency as target subcarriers as an example, this application selects a total of 12 subcarriers near the zero frequency for frequency domain signal reception. and As an observation sample.

[0048] The target subcarrier set is analyzed within a zero-frequency-centered window, and whether each subcarrier actually carries a DM-RS signal is determined by the LTE uplink resource allocation rules. Based on the LTE subcarrier mapping method and DM-RS allocation characteristics, these 12 target subcarriers may exhibit the following four scenarios under different resource configurations:

[0049] Scenario 1: All 12 target subcarriers are empty subcarriers, such as Figure 3 or Figure 4 As shown, at this time, these subcarriers do not carry any signals, and only DC leakage and noise components exist.

[0050] Scenario 2: All 12 target subcarriers are DM-RS subcarriers, as shown in the attached diagram. Figure 5 As shown. At this time, these target subcarriers carry the demodulation reference signal known to the receiver.

[0051] Scenario 3: Target subcarrier For DM-RS subcarriers, target subcarriers For empty subcarriers, see attached. Figure 6 As shown.

[0052] Scenario 4: Target subcarrier empty subcarrier, target subcarrier For DM-RS subcarriers, as shown in the attached document. Figure 7 As shown.

[0053] Different parameterized models are established for each scenario. Taking scenario 1 as an example, in this scenario, the 12 selected target subcarriers are all empty subcarriers, meaning that no modulation signal is carried on these target subcarriers, and they only contain DC leakage components and noise components. Therefore, the frequency domain received signal on each target subcarrier consists only of DC offset and noise, which can be expressed as:

[0054] ;

[0055] in, Indicates the first Frequency domain received information corresponding to each target subcarrier This represents the DC offset (which is an unknown parameter to be solved). Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The noise corresponding to each target subcarrier.

[0056] In this case, the signal model does not include a channel response term. With modulation symbol terms ,Right now: Therefore, the original parameterized model can be simplified to a linear relationship containing only the DC term.

[0057] For the reasons mentioned above, when each target subcarrier is an empty subcarrier, the coefficients corresponding to the DC offset for each target subcarrier are obtained. The coefficients corresponding to each target subcarrier and the DC offset are obtained. Frequency domain received information corresponding to each target subcarrier Substituting the original parametric model into the model yields the parametric model.

[0058] The parameterized model is represented as: ;in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier express . conjugate.

[0059] Using the above method, the DC component can be directly estimated in the unloaded frequency domain region without any signal, using the received signal near zero frequency. Furthermore, this method has low computational complexity, is simple to implement, and avoids signal interference, thus accurately extracting the DC leakage component and providing a reference benchmark for DC offset compensation in subsequent scenarios.

[0060] Taking scenario 2 as an example, in this scenario, all 12 selected target subcarriers are demodulation reference signal subcarriers. To ensure the model is solvable, this application assumes that there is no significant frequency-selective fading. Therefore, the frequency domain channel responses on these 12 target subcarriers are approximately equal and can all be denoted as... Therefore, the frequency domain received signal on the 12 subcarriers It can be uniformly represented in matrix form:

[0061] ;

[0062] in,

[0063] ;

[0064] ;

[0065] For noise A column vector formed by arranging the columns.

[0066] To estimate simultaneously and Applying the least squares (LS) method to the above linear model, we obtain:

[0067] ;

[0068] in,

[0069] ;

[0070] ;

[0071] ;

[0072] Represents the conjugate transpose operator;

[0073] therefore, and The fitting formula can be expanded as follows:

[0074] ;

[0075] ;

[0076] in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

[0077] In other words, when each target subcarrier is a demodulation reference signal subcarrier, the coefficients corresponding to the DC offset of each target subcarrier and the demodulation reference signal carried by each target subcarrier are obtained. The obtained coefficients corresponding to the DC offset of each target subcarrier, the demodulation reference signal carried by each target subcarrier and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterized model to obtain the parameterized model.

[0078] The parameterized model is represented as:

[0079] ;

[0080] in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

[0081] Taking scenario 3 as an example, in this scenario, the target subcarrier To demodulate the reference signal subcarrier, the target subcarrier 0 As empty subcarriers, to make the model solvable, this application assumes that there is no significant frequency-selective fading. Therefore, the frequency domain channel responses on these 12 target subcarriers are approximately equal and can all be denoted as... Therefore, the frequency domain received signal on the 12 subcarriers It can be uniformly represented in matrix form:

[0082] ;

[0083] matrix The second column is still A column vector arranged in order, but the first column becomes... That is, the last 6 elements of the first column are all 0. This represents the transpose operator.

[0084] Continue applying the least squares method, because the matrix The last 6 elements of the first column are all 0. and The fitting formula becomes:

[0085] ;

[0086] ;

[0087] In other words, when the 6 target subcarriers before the reference frequency point are demodulation reference signal subcarriers, and the target subcarriers corresponding to the reference frequency point and the 5 target subcarriers after the reference frequency point are empty subcarriers, the coefficients corresponding to the DC offset of each target subcarrier and the demodulation reference signal carried by each target subcarrier are obtained. The coefficients corresponding to the DC offset of each target subcarrier, the demodulation reference signal carried by each target subcarrier, and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterized model to obtain the parameterized model.

[0088] The parameterized model is represented as:

[0089] ;

[0090] in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

[0091] Taking scenario 4 as an example, in this scenario, the target subcarrier Empty subcarrier, target subcarrier 0 To demodulate the reference signal subcarrier, and to ensure the model is solvable, this application assumes no significant frequency-selective fading. Therefore, the frequency domain channel responses on these 12 target subcarriers are approximately equal and can all be denoted as... Therefore, the frequency domain received signal on the 12 subcarriers It can be uniformly represented in matrix form:

[0092] ;

[0093] matrix The second column remains unchanged, but the first column changes. That is, the first 6 elements of the first column are all 0.

[0094] Continue applying the least squares method. and The fitting formula becomes:

[0095] ;

[0096] .

[0097] In other words, when the six target subcarriers before the reference frequency point are empty subcarriers, and the target subcarriers corresponding to the reference frequency point and the five target subcarriers after the reference frequency point are demodulation reference signal subcarriers, the coefficients corresponding to the DC offset of each target subcarrier and the demodulation reference signal carried by each target subcarrier are obtained. The obtained coefficients corresponding to the DC offset of each target subcarrier, the demodulation reference signal carried by each target subcarrier, and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterized model to obtain the parameterized model.

[0098] The parameterized model is represented as:

[0099] ;

[0100] in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

[0101] All of the above-mentioned optional technical solutions can be combined in any way to form the optional embodiments of this application, and will not be described in detail here.

[0102] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0103] This embodiment also provides a DC offset determination device, such as... Figure 8 As shown, the DC offset determination device includes:

[0104] The acquisition module 801 is used to acquire uplink time-domain received symbols containing demodulation reference signals, and to perform frequency domain transformation on the uplink time-domain received symbols to obtain the corresponding frequency domain received information.

[0105] The selection module 802 is used to select multiple target subcarriers close to the reference frequency point in the transformed frequency domain received information as a reference.

[0106] Model module 803 is used to establish a parameterized model representing the correspondence between DC offset and frequency domain received information based on the frequency domain received information corresponding to each target subcarrier; and to determine the DC offset based on the parameterized model.

[0107] In some examples, model module 803 is also used to obtain a pre-set original parameterized model, substituting the frequency domain received information corresponding to each target subcarrier into the original parameterized model to establish the parameterized model; the original parameterized model is represented as:

[0108]

[0109] in, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates the first Channel response corresponding to each target subcarrier Indicates the first The modulation symbols carried by each target subcarrier Indicates DC offset. Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The noise corresponding to each target subcarrier.

[0110] In some examples, the selection module 802 is also used to select the six subcarriers before the reference frequency point, the subcarrier where the reference frequency point is located, and the five subcarriers after the reference frequency point as target subcarriers, based on the reference frequency point in the transformed frequency domain received information.

[0111] In some examples, model module 803 is also used to obtain the coefficients corresponding to the DC offset for each target subcarrier when each target subcarrier is an empty subcarrier, and to substitute the obtained coefficients corresponding to the DC offset for each target subcarrier and the frequency domain reception information corresponding to each target subcarrier into the original parameterized model to obtain the parameterized model.

[0112] The parameterized model is represented as:

[0113]

[0114] in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The coefficients corresponding to each target subcarrier.

[0115] In some examples, model module 803 is also used to obtain the coefficients corresponding to the DC offset of each target subcarrier and the demodulation reference signal carried by each target subcarrier when each target subcarrier is a demodulation reference signal subcarrier, and to substitute the obtained coefficients corresponding to the DC offset of each target subcarrier, the demodulation reference signal carried by each target subcarrier and the frequency domain reception information corresponding to each target subcarrier into the original parameterized model to obtain the parameterized model.

[0116] The parameterized model is represented as:

[0117]

[0118] in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

[0119] In some examples, model module 803 is also used to obtain the coefficients corresponding to the DC offset for each target subcarrier and the demodulation reference signal carried by each target subcarrier when the six target subcarriers before the reference frequency point are demodulation reference signal subcarriers and the target subcarriers corresponding to the reference frequency point and the five target subcarriers after the reference frequency point are empty subcarriers. The obtained coefficients corresponding to the DC offset for each target subcarrier, the demodulation reference signal carried by each target subcarrier, and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterized model to obtain the parameterized model.

[0120] The parameterized model is represented as:

[0121]

[0122] in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

[0123] In some examples, model module 803 is also used to obtain the coefficients corresponding to the DC offset for each target subcarrier and the demodulation reference signal carried by each target subcarrier when the six target subcarriers before the reference frequency point are empty subcarriers and the target subcarriers corresponding to the reference frequency point and the five target subcarriers after the reference frequency point are demodulation reference signal subcarriers. The obtained coefficients corresponding to the DC offset for each target subcarrier, the demodulation reference signal carried by each target subcarrier, and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterized model to obtain the parameterized model.

[0124] The parameterized model is represented as:

[0125]

[0126] in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

[0127] According to the technical solution provided in the embodiments of this application, the DC offset determination device acquires uplink time-domain received symbols containing demodulated reference signals and performs frequency-domain transformation on the uplink time-domain received symbols to obtain corresponding frequency-domain received information; using the reference frequency point in the transformed frequency-domain received information as a reference, multiple target subcarriers close to the reference frequency point are selected; based on the frequency-domain received information corresponding to each target subcarrier, a parameterized model characterizing the correspondence between DC offset and frequency-domain received information is established; and the DC offset is determined according to the parameterized model. This application performs frequency-domain transformation on the uplink time-domain received symbols containing demodulated reference signals, so that the mixed DC components in the time domain are concentrated to zero frequency and its neighboring subcarriers in the frequency domain, thereby facilitating identification and modeling; using the reference frequency point in the frequency-domain received information as a reference, only multiple target subcarriers close to the reference frequency point are selected for analysis, making the DC offset information more concentrated and the effective signal-to-noise ratio higher; and jointly establishing a parameterized model characterizing DC offset and frequency-domain received information based on the selected target subcarriers, and obtaining the DC offset accordingly, thereby improving the accuracy of the acquired DC offset and avoiding the problem of inaccurate acquisition of DC offset in the prior art.

[0128] Figure 9 This is a schematic diagram of the electronic device 9 provided in an embodiment of this application. Figure 9 As shown, the electronic device 9 of this embodiment includes a processor 901, a memory 902, and a computer program 903 stored in the memory 902 and executable on the processor 901. When the processor 901 executes the computer program 903, it implements the steps in the various method embodiments described above. Alternatively, when the processor 901 executes the computer program 903, it implements the functions of each module / unit in the various device embodiments described above.

[0129] Electronic device 9 can be a desktop computer, laptop, handheld computer, cloud server, or other electronic device. Electronic device 9 may include, but is not limited to, processor 901 and memory 902. Those skilled in the art will understand that... Figure 9 This is merely an example of electronic device 9 and does not constitute a limitation on electronic device 9. It may include more or fewer components than shown, or different components.

[0130] The processor 901 can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0131] The memory 902 can be an internal storage unit of the electronic device 9, such as a hard disk or RAM of the electronic device 9. The memory 902 can also be an external storage device of the electronic device 9, such as a plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, Flash Card, etc., equipped on the electronic device 9. The memory 902 can also include both internal and external storage units of the electronic device 9. The memory 902 is used to store computer programs and other programs and data required by the electronic device.

[0132] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0133] If an integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program may include computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. A computer-readable medium may include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in a computer-readable medium can be appropriately added to or subtracted according to the requirements of legislation and patent practice in a jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0134] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for determining DC offset, characterized in that, The method includes: The uplink time-domain received symbols containing the demodulation reference signal are acquired, and the uplink time-domain received symbols are frequency-domain transformed to obtain the corresponding frequency-domain received information. Using a reference frequency point in the transformed frequency domain received information as a reference, multiple target subcarriers close to the reference frequency point are selected; selecting multiple target subcarriers close to the reference frequency point in the transformed frequency domain received information as a reference includes: using the reference frequency point in the transformed frequency domain received information as a reference, taking the 6 subcarriers before the reference frequency point, the subcarrier where the reference frequency point is located, and the 5 subcarriers after the reference frequency point as the target subcarriers; the reference frequency point is a zero frequency point; Based on the frequency domain reception information corresponding to each target subcarrier, a parameterized model is established to characterize the correspondence between DC offset and frequency domain reception information; The DC offset is determined based on the parameterized model.

2. The method according to claim 1, characterized in that, Based on the frequency domain received information corresponding to the target subcarrier, a parameterized model characterizing the correspondence between DC offset and frequency domain received information is established, including: A pre-set original parameterized model is obtained, and the frequency domain received information corresponding to each target subcarrier is substituted into the original parameterized model to establish the parameterized model; the original parameterized model is expressed as: ； in, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates the first Channel response corresponding to each target subcarrier Indicates the first The modulation symbols carried by each target subcarrier Indicates DC offset. Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The noise corresponding to each target subcarrier.

3. The method according to claim 2, characterized in that, Substituting the frequency domain received information corresponding to each target subcarrier into the original parameterized model to establish the parameterized model includes: When each of the target subcarriers is an empty subcarrier, the coefficients corresponding to the DC offset for each target subcarrier are obtained, and the coefficients corresponding to the DC offset and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterized model to obtain the parameterized model. The parameterized model is represented as follows: ； in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The coefficients corresponding to each target subcarrier.

4. The method according to claim 2, characterized in that, Based on the frequency domain received information corresponding to the target subcarrier, a parameterized model characterizing the correspondence between DC offset and frequency domain received information is established, including: When each of the target subcarriers is a demodulation reference signal subcarrier, the coefficients corresponding to the DC offset and the demodulation reference signal carried by each target subcarrier are obtained. The obtained coefficients corresponding to the DC offset, the demodulation reference signal and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterization model to obtain the parameterization model. The parameterized model is represented as follows: in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

5. The method according to claim 2, characterized in that, Based on the frequency domain received information corresponding to the target subcarrier, a parameterized model characterizing the correspondence between DC offset and frequency domain received information is established, including: When the six target subcarriers before the reference frequency point are demodulation reference signal subcarriers, and the target subcarriers corresponding to the reference frequency point and the five target subcarriers after the reference frequency point are empty subcarriers, the coefficients corresponding to the DC offset of each target subcarrier and the demodulation reference signal carried by each target subcarrier are obtained. The obtained coefficients corresponding to the DC offset, the demodulation reference signal and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterized model to obtain the parameterized model. The parameterized model is represented as follows: in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

6. The method according to claim 2, characterized in that, Based on the frequency domain received information corresponding to the target subcarrier, a parameterized model characterizing the correspondence between DC offset and frequency domain received information is established, including: When the six target subcarriers before the reference frequency point are empty subcarriers, and the target subcarriers corresponding to the reference frequency point and the five target subcarriers after the reference frequency point are demodulation reference signal subcarriers, the coefficients corresponding to the DC offset of each target subcarrier and the demodulation reference signal carried by each target subcarrier are obtained. The obtained coefficients corresponding to the DC offset, the demodulation reference signal and the frequency domain reception information corresponding to each target subcarrier are substituted into the original parameterized model to obtain the parameterized model. The parameterized model is represented as follows: in, The range of values ​​for is [ , DC offset, Indicates the first Frequency domain received information corresponding to each target subcarrier Indicates DC offset in the 1st The corresponding coefficients on each target subcarrier Indicates the first The demodulation reference signal carried by each target subcarrier.

7. A DC offset determining device, characterized in that, The device includes: The acquisition module is used to acquire uplink time-domain received symbols containing demodulation reference signals, and to perform frequency domain transformation on the uplink time-domain received symbols to obtain corresponding frequency domain received information. The selection module is used to select multiple target subcarriers close to a reference frequency point in the transformed frequency domain received information, using the reference frequency point as a reference. Selecting multiple target subcarriers close to a reference frequency point in the transformed frequency domain received information includes: using the reference frequency point in the transformed frequency domain received information as a reference, selecting the 6 subcarriers before the reference frequency point, the subcarrier containing the reference frequency point, and the 5 subcarriers after the reference frequency point as the target subcarriers; the reference frequency point is a zero frequency point. The model module is used to establish a parameterized model representing the correspondence between DC offset and frequency domain received information based on the frequency domain received information corresponding to each target subcarrier; and to determine the DC offset according to the parameterized model.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 6.

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