Frequency offset estimation method, communication device, electronic device and storage medium

Abstract

Embodiments of the present invention provide a frequency offset estimation method, a communication device, an electronic device, and a computer-readable storage medium, relating to the field of communications. The frequency offset estimation method includes: obtaining the center frequency point positions of a plurality of first pilot subcarriers corresponding to a first OFDM symbol of a reference signal to obtain a plurality of first positions, and obtaining the center frequency point positions of a plurality of second pilot subcarriers corresponding to a second OFDM symbol of the reference signal to obtain a plurality of second positions; calculating the position differences between the first positions and the second positions; calculating a correlation value between the channel estimation values of each pair of corresponding first positions and second positions according to a channel fading factor, a delay parameter, and the position differences; and obtaining an estimated value of the frequency offset of the reference signal according to the correlation value. Compared with the prior art, the frequency offset estimation method, the communication device, the electronic device, and the computer-readable storage medium provided by the embodiments of the present invention have the advantage of being able to improve the accuracy of the frequency offset estimation result.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and in particular, to a frequency offset estimation method, a communication device, an electronic device, and a computer-readable storage medium. Background Art

[0002] Orthogonal frequency division multiplexing (OFDM) is one of the key technologies in modern communication systems and is a scheme for multi-channel system transmission. It mainly converts a single channel into several orthogonal sub-channels, that is, divides the frequency band into multiple sub-channels for data transmission, so as to convert a high-speed data signal into parallel low-speed sub-data streams, and then modulates them to transmit signals on each sub-channel. The orthogonality in orthogonal frequency division multiplexing means distinguishable, which means that it is convenient to distinguish two signals and electromagnetic waves, so these two signals are called orthogonal; frequency division is also called frequency division, which means that a signal is transmitted using multiple sub-carriers (used to carry the signal) to transmit information; multiplexing means that a certain frequency band is reused to achieve the reuse of frequency resources. An OFDM symbol includes a composite signal of multiple modulated sub-carriers, and each sub-carrier can be modulated by psk (phase shift keying) and qam (quadrature amplitude modulation). The OFDM transmitter maps the information bit stream into a psk or qam symbol sequence, and then converts the serial symbol sequence into a parallel symbol stream. Every N symbols after serial-to-parallel conversion are modulated by different sub-carriers, and the OFDM symbol is a composite signal of N parallel symbols.

[0003] In a wireless communication system, let the ideal waveform of the received baseband OFDM (Orthogonal Frequency Division Multiplexing) be y(t), and the actual received waveform be y′(t). Due to various reasons, there is a frequency offset difference between y(t) and y′(t), that is, there exists a frequency f0 such that This frequency offset will cause the receiving point to rotate relative to the transmitting point, and further cause the performance of the communication device at the receiving end to decline. Therefore, in order to improve the performance of the communication device at the receiving end, frequency offset estimation is essential.

[0004] In some standardized communication systems, the base station will send a reference signal for frequency synchronization. In the time domain, this reference signal generally occupies several OFDM symbols, and in the frequency domain, that is, on each OFDM symbol, this reference signal will occupy specific sub-carrier positions. These positions are called pilot sub-carriers. Generally, the center frequencies of the pilot sub-carriers on different OFDM symbols may be partially the same and partially different. This scenario is called the scenario where the pilot sub-carriers of different OFDM symbols are not aligned.

[0005] In the prior art, generally only those pilot subcarriers with the same center frequency are selected for frequency offset estimation. However, when the number of pilot subcarriers with the same center frequency in two OFDM symbols is small, the noise reduction effect is limited, resulting in a significant reduction in the accuracy of the frequency offset estimation results in the prior art. And when the number of pilot subcarriers with the same center frequency in two OFDM symbols is zero, the frequency offset estimation method in the prior art is even completely infeasible. If the pilot subcarriers with different center frequencies on different OFDM symbols are directly used to perform frequency offset estimation by imitating the above method, the accuracy of the estimation results will be further reduced and may even be completely wrong. Summary of the Invention

[0006] An object of the present invention is to provide a frequency offset estimation method, a communication device, an electronic device, and a computer-readable storage medium, which can improve the accuracy of the frequency offset estimation results.

[0007] In a first aspect, an embodiment of the present invention provides a frequency offset estimation method, including: obtaining delay parameters corresponding to respective multiple signal transmission paths of a reference signal; obtaining first channel fading factors corresponding to the respective signal transmission paths in a first OFDM symbol; obtaining second channel fading factors corresponding to the respective signal transmission paths in a second OFDM symbol; obtaining center frequency positions of multiple first pilot subcarriers corresponding to the reference signal in the first OFDM symbol to obtain multiple first positions, obtaining center frequency positions of multiple second pilot subcarriers corresponding to the reference signal in the second OFDM symbol to obtain multiple second positions, where the number of the multiple first positions is equal to that of the multiple second positions and they correspond one by one; calculating position differences between the mutually corresponding first positions and second positions; calculating a correlation value between a channel estimation value of each mutually corresponding first position and a channel estimation value of the second position according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference; and obtaining an estimated value of the frequency offset of the reference signal according to the correlation value.

[0008] In some embodiments, when all the position differences are equal, the calculating the correlation value between the first OFDM symbol and the second OFDM symbol of the communication channel according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference includes: calculating the correlation value according to the formula to obtain the correlation value; where corr is the correlation value, l is an index of each signal transmission path, T is a set of indices of all the signal transmission paths, e is the natural logarithm, π is the pi, j is a complex number symbol, D g is the position difference, τ l is the delay parameter of the signal transmission path with index l, al (t0) is the first channel fading factor corresponding to the signal transmission path with index l, a l (t1) is the second channel fading factor corresponding to the signal transmission path with index l.

[0009] In some embodiments, calculating the correlation value of the communication channel between the first OFDM symbol and the second OFDM symbol according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference includes: obtaining a target parameter according to the delay parameter, where the target parameter is used to offset the difference between the first position and the second position corresponding to each other; calculating the first position, the second position, the first channel fading factor, the second channel fading factor, the delay parameter, and the target parameter according to a preset formula to obtain the correlation value; the preset formula includes: where X is the target parameter, corr is the correlation value, l is the index of each signal transmission path, T is the index set of all signal transmission paths, e is the natural logarithm, π is the pi, j is the complex symbol, i is the index of the first OFDM symbol and the second OFDM symbol, k is the index of the first position and the second position corresponding to each other, P is the total number of the first position and the second position, is the center frequency point position of the OFDM symbol with index i at the first position or the second position with index k, is the position difference between the first position and the second position with index k, τ l is the delay parameter of the signal transmission path with index l, a l (t0) is the first channel fading factor corresponding to the signal transmission path with index l, a l (t1) is the second channel fading factor corresponding to the signal transmission path with index l.

[0010] In some embodiments, obtaining the target parameter according to the delay parameter includes: obtaining a target path with the maximum power among the multiple signal transmission paths; using the delay parameter of the target path as the target parameter.

[0011] In some embodiments, obtaining the target parameter according to the delay parameter includes: obtaining the weight value corresponding to each signal transmission path; obtaining the target parameter according to the weight value and the delay parameter.

[0012] In some embodiments, obtaining the weight values corresponding to each of the signal transmission paths includes: obtaining the constant fading factors corresponding to each of the signal transmission paths; and respectively using the squared operation values of the constant fading factors corresponding to each of the signal transmission paths as the weight values corresponding to each of the signal transmission paths.

[0013] In some embodiments, obtaining the frequency offset estimation of the communication device according to the correlation value includes: obtaining the time difference between the reception time corresponding to the first OFDM symbol and the reception time corresponding to the second OFDM symbol; and obtaining the estimation of the frequency offset according to the correlation value and the time difference.

[0014] In a second aspect, an embodiment of the present invention further provides a communication device, including: a delay parameter obtaining module, configured to obtain the delay parameters respectively corresponding to multiple signal transmission paths of a reference signal; a fading factor obtaining module, configured to obtain the first channel fading factors corresponding to each of the signal transmission paths at the first OFDM symbol, and the fading factor obtaining module is further configured to obtain the second channel fading factors corresponding to each of the signal transmission paths at the second OFDM symbol; a frequency point obtaining module, configured to obtain the center frequency point positions of multiple first pilot subcarriers corresponding to the reference signal at the first OFDM symbol to obtain multiple first positions, obtain the center frequency point positions of multiple second pilot subcarriers corresponding to the reference signal at the second OFDM symbol to obtain multiple second positions, where the number of the multiple first positions is equal to that of the multiple second positions and they correspond one by one; a delay estimation module, configured to calculate the position difference between the mutually corresponding first position and the second position, calculate the correlation value between the channel estimation values of the mutually corresponding first position and the second position according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference, and obtain the estimation of the frequency offset of the reference signal according to the correlation value.

[0015] In a third aspect, an embodiment of the present invention further provides an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and when the instructions are executed by the at least one processor, the at least one processor is enabled to execute the frequency offset estimation method as described above.

[0016] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, storing a computer program, characterized in that when the computer program is executed by a processor, the frequency offset estimation method as described above is implemented.

[0017] Compared with the prior art, in the frequency offset estimation method, communication device, electronic device, and computer-readable storage medium provided by the embodiments of the present invention, the position difference between the center frequency point positions of the reference signal on the first pilot subcarrier corresponding to the first OFDM symbol and the center frequency point positions of the reference signal on the second pilot subcarrier corresponding to the second OFDM symbol is obtained. Combining the delay parameters corresponding to the multiple signal transmission paths of the reference signal, the first signal fading factor and the second channel fading factor of each signal transmission path of the reference signal corresponding to the first OFDM symbol and the second OFDM symbol, a correlation value of the channel estimation value of the center frequency point position of the reference signal on the first pilot subcarrier corresponding to the first OFDM symbol and the center frequency point position of the reference signal on the second pilot subcarrier corresponding to the second OFDM symbol is jointly calculated, and an estimated value of the frequency offset of the reference signal is obtained according to the correlation value. Combining the position difference to perform an estimation calculation on the frequency offset of the reference signal can still accurately perform the frequency offset estimation calculation when the pilot subcarriers on different OFDM symbols are not aligned, thereby improving the accuracy of the frequency offset estimation result. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is a schematic flowchart of the frequency offset estimation method provided by Embodiment 1 of the present invention;

[0020] Figure 2 It is a schematic structural diagram of the communication device provided by Embodiment 2 of the present invention;

[0021] Figure 3 It is a schematic structural diagram of the electronic device provided by Embodiment 3 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0023] Accordingly, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0024] It should be noted that like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it is not necessary to further define and explain it in subsequent drawings.

[0025] In the description of the present invention, it should be noted that if terms such as "upper", "lower", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings or the orientation or positional relationship in which the product of the invention is customarily placed. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0026] In addition, if terms such as "first", "second", etc. are used only for distinguishing descriptions, they cannot be understood as indicating or implying relative importance.

[0027] It should be noted that, without conflict, the features in the embodiments of the present invention can be combined with each other.

[0028] Embodiment 1 of the present invention provides a frequency offset estimation method, specifically as Figure 1 shown, including the following steps:

[0029] Step S101: Obtain the delay parameters corresponding to each of the multiple signal transmission paths of the reference signal.

[0030] In this step, the reference signal is a signal sent by the base station for the terminal to perform frequency offset estimation, and the reference signal includes at least two OFDM symbols, namely the first OFDM symbol and the second OFDM symbol. In some embodiments of the present invention, the reference signal may also include other OFDM symbols. For example, the reference signal may include 3, 4, or more OFDM symbols.

[0031] Step S102: Obtain the first channel fading factor corresponding to each signal transmission path in the first OFDM symbol, and obtain the second channel fading factor corresponding to each signal transmission path in the second OFDM symbol.

[0032] In this step, the specific steps for obtaining the first channel fading factor corresponding to the first OFDM symbol for each signal transmission path are as follows: For each signal transmission path, first extract the pilot data on the first OFDM symbol, then multiply the pilot data by the conjugate of the known pilot pattern, and then perform a Fourier transform on this series of values to obtain the first channel fading factor corresponding to the signal transmission path on the first OFDM symbol.

[0033] Furthermore, the same steps as those for obtaining the first channel fading factor corresponding to the first OFDM symbol for each signal transmission path can be used to obtain the second channel fading factor corresponding to the second OFDM symbol for each signal transmission path. For specific details, reference can be made to the foregoing specific description.

[0034] Step S103: Obtain the center frequency point positions of multiple first pilot subcarriers corresponding to the reference signal in the first OFDM symbol to obtain multiple first positions, and obtain the center frequency point positions of multiple second pilot subcarriers corresponding to the reference signal in the second OFDM symbol to obtain multiple second positions.

[0035] In a standardized communication system, the reference signal generally occupies several OFDM symbols in the time domain. For example, in this embodiment, they are the first OFDM symbol and the second OFDM symbol. In the frequency domain, that is, on each OFDM symbol, the reference signal will occupy specific subcarrier positions, and these positions are called pilot subcarriers.

[0036] In some embodiments of the present invention, the first OFDM symbol and the second OFDM symbol are respectively marked as 0 and 1, and the first position and the second position can be expressed as where i ∈ {0, 1} identifies the first OFDM symbol and the second OFDM symbol, and p i is the number of the first position and the second position.

[0037] Step S104: Calculate the position difference between the mutually corresponding first position and second position.

[0038] In this step, the position difference between the mutually corresponding first position and second position is a constant value D that does not depend on the index k of the first position and the second position g . That is, for any k ∈ {0, 1,..., P i -1}, there exists a constant value D g such that

[0039] Furthermore, in some embodiments of the present invention, it is also possible to calculate the position differences of each pair of mutually corresponding first position and second position respectively to obtain multiple position differences, and then calculate the average value of the multiple position differences as the final position difference.

[0040] Step S105: Calculate the correlation value between the channel estimation values of the corresponding first positions and the channel estimation values of the second positions according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference.

[0041] In different embodiments of the present application, there are two cases where all the position differences are equal and where the position differences are not equal. For these two cases, the following will provide a detailed description of each case separately.

[0042] (1) In the case where all the position differences are equal, calculating the correlation value of the communication channel between the first OFDM symbol and the second OFDM symbol according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference includes:

[0043] Calculate the correlation value according to the formula ;

[0044] where corr is the correlation value, l is the index of each signal transmission path, T is the set of indices of all signal transmission paths, e is the natural logarithm, π is the pi, j is the complex number symbol, D g is the position difference, τ l is the delay parameter of the signal transmission path with index l, a l (t0) is the first channel fading factor corresponding to the signal transmission path with index l, a l (t1) is the second channel fading factor corresponding to the signal transmission path with index l.

[0045] (2) In the case where there are unequal position differences, calculating the correlation value of the communication channel between the first OFDM symbol and the second OFDM symbol according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference includes:

[0046] Obtain the target parameter according to the delay parameter, and the target parameter is used to offset the difference between the corresponding first position and the second position.

[0047] Calculate the first position, the second position, the first channel fading factor, the second channel fading factor, the delay parameter, and the target parameter according to the formula to obtain the correlation value.

[0048] where X is the target parameter, corr is the correlation value, l is the index of each signal transmission path, T is the set of indices of all signal transmission paths, e is the natural logarithm, π is the pi, j is the complex number symbol, i is the index of the first OFDM symbol and the second OFDM symbol, k is the index of the corresponding first position and the second position, P is the total number of the first position and the second position, is the center frequency position of the OFDM symbol with index i at the first position or the second position with index k. is the position difference between the first position and the second position with index k, τ l is the delay parameter of the signal transmission path with index l, a l (t0) is the first channel fading factor corresponding to the signal transmission path with index l, a l (t1) is the second channel fading factor corresponding to the signal transmission path with index l.

[0049] Among them, different acquisition methods can be adopted to obtain the target parameter according to the delay parameter in different embodiments of the present application. For example, in some embodiments of the present application, the target path with the maximum power among multiple signal transmission paths can be obtained; the delay parameter of the target path is used as the target parameter. Mathematically expressed as l S = argmax l∈T (|c l |), where l S is the target parameter, c l is a constant fading factor. According to the formula it can be known that the channel fading factor a l (t i )(classified into the first channel fading factor and the second channel fading factor according to the value of i) is composed of the constant fading factor c l and the phase generated by the frequency offset.

[0050] Or in some other embodiments of the present application, it may also be to obtain the weight value corresponding to each signal transmission path; obtain the target parameter according to the weight value and the delay parameter. The channel fading factor a l (t i ) is composed of the constant fading factor c l and the phase generated by the frequency offset. In some embodiments of the present invention, the square operation value of the constant fading factor in each first channel fading factor can be obtained as the weight value corresponding to the signal transmission path, which can be specifically expressed as the weight value Q of the signal transmission path with index l l = |c l | 2 , and then the target parameter is obtained according to the weight value Q l of the signal transmission path with index l and the delay parameter τ l , for example, the target parameter <τ> is obtained according to the formula

[0051] .

[0052] Step S106: Obtain an estimate of the frequency offset of the reference signal according to the correlation value.

[0053] In this step, specifically, the time difference Δt = t1 - t0 between the reception time corresponding to the first OFDM symbol and the reception time corresponding to the second OFDM symbol can be obtained; the frequency offset estimation value is obtained based on the correlation value corr and the time difference Δt.

[0054] Specifically, in some embodiments of the present invention, it can be specifically calculated according to the formula to obtain the frequency offset estimation value of the communication device where angle(corr) is the phase of the complex number corr.

[0055] Compared with the prior art, in the frequency offset estimation method provided in the first embodiment of the present application, the position difference between the center frequency point positions of the first pilot subcarrier corresponding to the reference signal in the first OFDM symbol and the second pilot subcarrier corresponding to the reference signal in the second OFDM symbol is obtained, combined with the delay parameters corresponding to the multiple signal transmission paths of the reference signal, the first signal fading factor and the second channel fading factor corresponding to each signal transmission path of the reference signal in the first OFDM symbol and the second OFDM symbol, and the correlation value of the channel estimation value of the center frequency point position of the first pilot subcarrier corresponding to the reference signal in the first OFDM symbol and the center frequency point position of the second pilot subcarrier corresponding to the reference signal in the second OFDM symbol is jointly calculated, and the frequency offset estimation value of the reference signal is obtained based on the correlation value. By combining the position difference to perform the frequency offset estimation calculation on the reference signal, when the pilot subcarriers on different OFDM symbols are not aligned, the frequency offset estimation calculation can still be accurately performed, thereby improving the accuracy of the frequency offset estimation result.

[0056] Embodiment 2 of the present invention provides a communication device, specifically as Figure 2As shown in the figure, it includes: a time delay parameter acquisition module 201, which is used to acquire the time delay parameters corresponding to each of the multiple signal transmission paths of the reference signal; a fading factor acquisition module 202, which is used to acquire the first channel fading factors corresponding to each of the signal transmission paths in the first OFDM symbol, and the fading factor acquisition module is also used to acquire the second channel fading factors corresponding to each of the signal transmission paths in the second OFDM symbol; a frequency point acquisition module 203, which is used to acquire the center frequency point positions of the multiple first pilot subcarriers corresponding to the reference signal in the first OFDM symbol to obtain multiple first positions, and acquire the center frequency point positions of the multiple second pilot subcarriers corresponding to the reference signal in the second OFDM symbol to obtain multiple second positions, and the number of the multiple first positions and the multiple second positions is equal and they correspond one by one; a time delay estimation module 204, which is used to calculate the position difference between the mutually corresponding first position and the second position, calculate the correlation value between the channel estimation values of the mutually corresponding first position and the second position according to the first channel fading factor, the second channel fading factor, the time delay parameter, and the position difference, and obtain the estimation value of the frequency offset of the reference signal according to the correlation value.

[0057] Compared with the prior art, in the communication device provided in the second embodiment of the present application, the time delay estimation module 204 acquires the position difference between the center frequency point position of the first pilot subcarrier corresponding to the reference signal in the first OFDM symbol and the center frequency point position of the second pilot subcarrier corresponding to the reference signal in the second OFDM symbol, combines the time delay parameters corresponding to each of the multiple signal transmission paths of the reference signal acquired by the time delay parameter acquisition module 201, and the first signal fading factor and the second channel fading factor corresponding to each of the signal transmission paths of the reference signal acquired by the fading factor acquisition module 202 in the first OFDM symbol and the second OFDM symbol, and jointly calculates the correlation value of the channel estimation values of the center frequency point position of the first pilot subcarrier corresponding to the reference signal in the first OFDM symbol and the center frequency point position of the second pilot subcarrier corresponding to the reference signal in the second OFDM symbol, and obtains the estimation value of the frequency offset of the reference signal according to the correlation value. By combining the position difference to perform the estimation calculation of the frequency offset of the reference signal, it is possible to accurately perform the frequency offset estimation calculation even when the pilot subcarriers in different OFDM symbols are not aligned, thereby improving the accuracy of the frequency offset estimation result.

[0058] Embodiment 3 of the present invention provides an electronic device, such as Figure 3 As shown in the figure, it includes: at least one processor 301; and a memory 302 communicatively connected to the at least one processor 301; wherein, the memory 302 stores instructions executable by the at least one processor 301, and the instructions are executed by the at least one processor 301 so that the at least one processor 301 can execute the frequency offset estimation method in the above embodiments.

[0059] Among them, the memory and the processor are connected in a bus manner. The bus can include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors and memories together. The bus can also connect various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art, so they will not be further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be a single component or multiple components, such as multiple receivers and transmitters, and provides a unit for communicating with various other devices on the transmission medium. The data processed by the processor is transmitted on the wireless medium through the antenna. Further, the antenna also receives data and transmits the data to the processor.

[0060] The processor is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interface, voltage regulation, power management, and other control functions. The memory can be used to store the data used by the processor when executing operations.

[0061] Embodiment 4 of the present invention relates to a computer-readable storage medium storing a computer program. When the computer program is executed by the processor, the above method embodiment is implemented.

[0062] That is, those skilled in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by instructing relevant hardware through a program. The program is stored in a storage medium and includes several instructions to enable a device (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute all or part of the steps of the method embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes.

[0063] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A frequency offset estimation method, characterized in that, The method includes: Obtaining delay parameters corresponding to respective multiple signal transmission paths of a reference signal; Obtaining first channel fading factors corresponding to respective signal transmission paths in a first OFDM symbol; Obtaining second channel fading factors corresponding to respective signal transmission paths in a second OFDM symbol; Obtaining center frequency point positions of multiple first pilot subcarriers corresponding to the reference signal in the first OFDM symbol to obtain multiple first positions, and obtaining center frequency point positions of multiple second pilot subcarriers corresponding to the reference signal in the second OFDM symbol to obtain multiple second positions, where the number of the multiple first positions is equal to that of the multiple second positions and they correspond one by one; Calculating a position difference between the mutually corresponding first position and second position; Calculating a correlation value between a channel estimation value of each mutually corresponding first position and a channel estimation value of the second position according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference; Obtaining an estimation value of the frequency offset of the reference signal according to the correlation value.

2. The frequency offset estimation method according to claim 1, characterized in that, When all the position differences are equal, the calculating the correlation value of the communication channel between the first OFDM symbol and the second OFDM symbol according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference includes: According to the formula the relevant value is calculated where corr is the correlation value, l is the index of each signal transmission path, T is the set of indices of all the signal transmission paths, e is the natural logarithm, π is the pi, j is the complex symbol, D g is the position difference, τ l is the delay parameter of the signal transmission path with index l, a l (t0) is the first channel fading factor corresponding to the signal transmission path with index l, a l (t1) is the second channel fading factor corresponding to the signal transmission path with index l.

3. The frequency offset estimation method according to claim 1, characterized in that, The calculating the correlation value of the communication channel between the first OFDM symbol and the second OFDM symbol according to the first channel fading factor, the second channel fading factor, the delay parameter, and the position difference includes: Obtaining a target parameter according to the delay parameter, where the target parameter is used to offset the difference between the mutually corresponding first position and second position; Calculating the correlation value according to the first position, the second position, the first channel fading factor, the second channel fading factor, the delay parameter, and the target parameter according to a preset formula; The preset formula includes: Wherein, X is the target parameter, corr is the correlation value, l is the index of each signal transmission path, T is the index set of all the signal transmission paths, e is the natural logarithm, π is the pi, j is the complex symbol, i is the index of the first OFDM symbol and the second OFDM symbol, k is the index of the corresponding first position and second position, and P is the total number of the first position and the second position. is the center frequency point position of the OFDM symbol with index i at the first position or the second position with index k. is the position difference between the first position and the second position with index k, and τ l is the delay parameter of the signal transmission path with index l, and a l (t0) is the first channel fading factor corresponding to the signal transmission path with index l, and a l (t1) is the second channel fading factor corresponding to the signal transmission path with index l.

4. The frequency offset estimation method according to claim 3, characterized in that, The obtaining the target parameter according to the delay parameter includes: Obtaining a target path with the maximum power among the multiple signal transmission paths; Taking the delay parameter of the target path as the target parameter.

5. The frequency offset estimation method according to claim 3, characterized in that, Obtaining the target parameter according to the delay parameter includes: Obtaining weight values corresponding to respective signal transmission paths; Obtaining the target parameter according to the weight values and the delay parameter.

6. The frequency offset estimation method according to claim 5, characterized in that, The obtaining the weight values corresponding to respective signal transmission paths includes: Obtaining constant fading factors corresponding to respective signal transmission paths; Taking squared operation values of the constant fading factors corresponding to respective signal transmission paths as the weight values corresponding to respective signal transmission paths.

7. The frequency offset estimation method according to any one of claims 1 to 6, characterized in that, The obtaining the frequency offset estimation value of the communication device according to the correlation value includes: Obtaining a time difference between a reception time corresponding to the first OFDM symbol and a reception time corresponding to the second OFDM symbol; Obtaining the estimation value of the frequency offset according to the correlation value and the time difference.

8. A communication device, characterized in that, Includes: A time delay parameter acquisition module, which is used to acquire the time delay parameters corresponding to multiple signal transmission paths of a reference signal; A fading factor acquisition module, which is used to acquire the first channel fading factors corresponding to each of the signal transmission paths in a first OFDM symbol, and the fading factor acquisition module is further used to acquire the second channel fading factors corresponding to each of the signal transmission paths in a second OFDM symbol; A frequency point acquisition module, which is used to acquire the center frequency point positions of multiple first pilot subcarriers corresponding to the reference signal in the first OFDM symbol to obtain multiple first positions, and acquire the center frequency point positions of multiple second pilot subcarriers corresponding to the reference signal in the second OFDM symbol to obtain multiple second positions, and the number of the multiple first positions is equal to and corresponds one by one to the number of the multiple second positions; A time delay estimation module, which is used to calculate the position difference between the mutually corresponding first position and the second position, calculate the correlation value between the channel estimation value of each mutually corresponding first position and the channel estimation value of the second position according to the first channel fading factor, the second channel fading factor, the time delay parameter, and the position difference, and obtain the estimation value of the frequency offset of the reference signal according to the correlation value.

9. An electronic device, characterized in that, Comprising: At least one processor; And a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the frequency offset estimation method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, The computer program is executed by a processor to implement the frequency offset estimation method according to any one of claims 1 to 7.

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