A high-frequency high-speed frequency hopping system frequency offset calculation method and terminal

Abstract

The application discloses a frequency offset calculation method and a terminal in a high-frequency high-speed frequency hopping system. The frequency offset calculation method comprises the following steps: performing first correction on a received signal according to an initial frequency offset at a receiving end; rotating synchronization header data of the received signal, so that the phase of the rotated synchronization header data and the phase of service data are located in the same quadrant; combining the rotated synchronization header data and the service data; performing first equalization calculation on the combined data to obtain an average frequency offset of the combined data; performing second correction on the received data after the first correction based on the average frequency offset of the combined data to obtain corrected data; and performing second equalization calculation on the corrected data to obtain an accurate received signal. Through the calculation of the average frequency offset, the twice correction and equalization calculation are performed on the received data, the residual frequency offset range is reduced, and the accuracy of the received signal is improved.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a method for calculating frequency offset and a terminal in a high-frequency, high-speed frequency hopping system. Background Technology

[0002] Frequency-hopping (FHSS) is one of the most commonly used spread spectrum techniques in wireless communication. It involves discretely changing the carrier frequency of the wireless signal transmitted by both transmitting and receiving devices according to a predetermined algorithm or rule. In other words, the carrier frequency used in wireless communication is randomly changed under the control of a pseudo-random change code. From a technical implementation perspective, FHSS is a communication method that uses code sequences for multi-frequency frequency shift keying, and it is also a code-controlled carrier frequency hopping communication system. In the time domain, a FHSS signal is a multi-frequency frequency shift keying signal; in the frequency domain, the spectrum of a FHSS signal randomly changes at unequal intervals across a wide frequency band.

[0003] At the receiving end of a communication system, accurate estimation and compensation of frequency offset are necessary before data can be successfully demodulated. Accurate estimation of frequency offset is crucial for achieving good demodulation performance.

[0004] Traditional fixed frequency-hopping scattering communication systems typically use the pilot signal for each hop to estimate the frequency offset. The average of these multi-hop frequency offset estimates is then used for frequency offset compensation. However, at high frequencies and high flight speeds, the data length of a single hop in the frequency-hopping system is limited, resulting in a finite pilot sequence length. This prevents the accurate estimation of the frequency offset, leading to a relatively large residual frequency offset after pilot correction.

[0005] In a single-hop signal, there is a phase conflict between the synchronization header data and the service data. In the current frequency offset estimation, the frequency offset is calculated based on the synchronization header data, without involving the service data.

[0006] Therefore, how to accurately calculate and correct the frequency offset generated by the one-hop signal at the receiving end is an urgent problem to be solved. Summary of the Invention

[0007] The purpose of this invention is to provide a frequency offset calculation method and terminal in a high-frequency, high-speed frequency hopping system. By rotating the synchronization header data, the phase of the synchronization header data and the phase of the service data are located in the same quadrant. An equalization calculation is performed on the rotated synchronization header data, or the combined data of the rotated synchronization header data and the service data, to obtain the average frequency offset. Based on the average frequency offset correction data, an equalization calculation is performed on the correction data to obtain accurate received data, thereby reducing the residual frequency offset range of the received data and improving the accuracy of the received signal.

[0008] Firstly, the above-mentioned objective of this invention is achieved through the following technical solution:

[0009] A frequency offset calculation method in a high-frequency, high-speed frequency hopping system includes, at the receiver end, performing a first correction on the received signal based on the initial frequency offset, rotating the synchronization header data of the received signal so that the phase of the rotated synchronization header data is in the same quadrant as the phase of the service data, performing a first equalization calculation on the rotated synchronization header data to obtain the average frequency offset of the synchronization header, performing a second correction on the received data after the first correction to obtain corrected data, and performing a second equalization calculation on the corrected data to obtain an accurate received signal.

[0010] Secondly, the above-mentioned objective of this invention is achieved through the following technical solution:

[0011] A frequency offset calculation method in a high-frequency, high-speed frequency hopping system includes, at the receiver end, performing a first correction on the received signal based on the initial frequency offset, rotating the synchronization header data of the received signal so that the phase of the rotated synchronization header data and the phase of the service data are in the same quadrant, combining the rotated synchronization header data and the service data, performing a first equalization calculation on the combined data to obtain the average frequency offset of the combined data, performing a second correction on the received data after the first correction based on the average frequency offset of the combined data to obtain corrected data, and performing a second equalization calculation on the corrected data to obtain an accurate received signal.

[0012] Thirdly, the above-mentioned objectives of this invention are achieved through the following technical solutions:

[0013] A frequency offset calculation method in a high-frequency, high-speed frequency hopping system includes the following steps at the receiver: First, a first correction is performed on the received signal based on the initial frequency offset. Then, the synchronization header data of the received signal is rotated so that the phase of the rotated synchronization header data is in the same quadrant as the phase of the service data. A first equalization calculation is performed on the rotated synchronization header data to obtain the average frequency offset of the synchronization header. A second correction is performed on the received data after the first correction to obtain corrected synchronization header data. A second equalization calculation is performed on the corrected synchronization header data to obtain the range of memory factor values. The rotated synchronization header data and service data are then combined. Based on the range of memory factor values, a first equalization calculation is performed on the combined data to obtain the average frequency offset of the combined data. The average frequency offset of the combined data is then further corrected on the received data after the first correction to obtain corrected received signal data. Finally, a second equalization calculation is performed on the corrected received signal data to obtain a precise received signal.

[0014] The present invention is further configured to: rotate the synchronization header data by PI / 4, that is, rotate it by 45 degrees; set the memory factor value to be larger during the first equalization calculation, and set the memory factor value to be smaller during the second equalization calculation.

[0015] The present invention is further configured such that: during the first balancing calculation, the memory factor is set to [1 / 2^5, 1 / 2^6], and during the second balancing calculation, the memory factor is set to [1 / 2^7, 1 / 2^8].

[0016] The present invention is further configured to: perform equalization calculation using a modified constant modulus algorithm, perform equalization calculation on one input signal in a one-hop received signal, obtain multiple weighted vector iteration values, obtain the maximum value of the weighted vector iteration, and calculate the phase vector.

[0017] The present invention is further configured as follows: equalization calculation is performed on different input signals to obtain a phase vector group; the phase difference generated by the phase vectors of adjacent time points is obtained according to the corresponding time of the input signal; the frequency offset is calculated according to the phase difference; the average of all frequency offsets is calculated to obtain the average frequency offset; the received signal after the first correction is corrected according to the average frequency offset to obtain the corrected data.

[0018] The present invention is further configured as follows: removing the first segment data from a one-hop signal, obtaining the phase vector of the second segment data to obtain a phase vector group, dividing the second segment data into a first part and a second part according to time, obtaining the average value of the phase difference between the second part phase vector and the first part phase vector, and obtaining the average frequency deviation based on the average value of the phase difference.

[0019] The present invention is further configured such that the third set of phase vectors is as follows:

[0020] θ_List3=[θ(Ls+1), θ(Ls+2), ...θ(Ls+Ld) (13);

[0021] Following the chronological order, the third set of phase vector signals is divided into two parts. The phase difference between the second time interval and the first time interval is averaged to obtain the average phase difference Δθ.

[0022]

[0023] Calculate the average frequency offset, i.e., the second frequency offset Δf2, based on the average phase difference Δθ:

[0024]

[0025] In the formula, f b Indicates the symbol rate of the physical layer;

[0026] Based on the first and second frequency offsets, the second residual frequency offset f is calculated.res2

[0027] f res2 =f doppler -(Δf1+Δf2) (16);

[0028] In the formula, f doppler Δf1 represents the actual frequency offset of the received signal, and Δf1 represents the initial frequency offset.

[0029] Fourthly, the above-mentioned objective of this invention is achieved through the following technical solutions:

[0030] A frequency offset calculation terminal in a high-frequency, high-speed frequency hopping system includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the method described in this application.

[0031] Compared with the prior art, the beneficial technical effects of this application are as follows:

[0032] 1. This application rotates the synchronization header data so that the phase of the synchronization header data and the phase of the service data are in the same quadrant, so that the synchronization header data and the service data can be jointly calculated.

[0033] 2. Furthermore, this application obtains the average frequency offset through the first equalization calculation, and makes corrections based on the average frequency offset, thereby narrowing the range of residual frequency offset;

[0034] 3. Furthermore, this application performs another equalization calculation on the data after the second frequency offset correction to further resist large frequency offset and noise. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of frequency hopping signals in existing technology;

[0036] Figure 2 This is a constellation diagram of the synchronization header data before and after rotation according to a specific embodiment of this application;

[0037] Figure 3 This is a schematic diagram of the frequency offset simulation results of a specific embodiment of this application;

[0038] Figure 4 This is a schematic flowchart of a frequency offset calculation method according to a specific embodiment of this application;

[0039] Figure 5 This is a schematic diagram comparing the frequency offset calculation result with the actual frequency offset in a specific embodiment of this application. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to the accompanying drawings.

[0041] The first and second order descriptions in this application are only used to distinguish different contents and do not imply any order or ranking.

[0042] This application discloses a method for calculating frequency offset in a high-frequency, high-speed frequency-hopping system, comprising: generating service data (QPSK, Quadrature Phase Shift Keying) of length Ld at the transmitter, and generating synchronization header data (BPSK, Binary Phase Shift Keying) of length Ls to determine the position of each hop signal; transmitting the hop signal at each moment; the frequency hopping point is different at different moments; the current hop signal is at the first frequency point at the current moment, and the next hop signal is at the next frequency point at the next moment, forming a frequency-hopping signal; and determining the position of each hop signal according to the different frequencies. Figure 1 As shown.

[0043] The synchronization header data includes a synchronization header input signal containing a certain amount of data, and the service data includes a service input signal containing a certain amount of data. The input signal in this application refers to the synchronization header input signal and / or the service input signal. Different input signals refer to different synchronization header input signals and / or different service input signals.

[0044] When the receiving end receives a one-hop reception signal, it slides the local synchronization header data with the received signal to obtain the synchronization header position of the received signal. Based on the synchronization header position in the one-hop signal, it calculates the initial frequency offset of the current hop signal and performs the first correction on the current hop reception signal to obtain the first corrected signal.

[0045] After rotating the synchronization head data, a first synchronization head memory factor is set, the first equalization calculation is performed, the second frequency offset of the synchronization head is calculated, the first correction signal is corrected to obtain the second correction signal, the second synchronization head memory factor is set, the second equalization operation is performed on the second correction data to obtain the corrected data, and the residual frequency offset is reduced.

[0046] During the first equalization operation, a first synchronization head memory factor is set, and a weighted vector iteration is performed on an input signal. After each iteration of the weighted vector, multiple calculation results are obtained. The maximum value is obtained from the multiple calculation results, the phase corresponding to the maximum value is calculated, and stored.

[0047] For different input signals in a one-hop signal, weighted vector iterative calculation is performed. After multiple weighted vector iterative calculations, a series of phase values ​​are obtained, forming a phase vector group.

[0048] The phase vector groups are sorted in time order, the phase deviation between adjacent time periods is calculated, and the average value of all phase deviations is obtained to obtain the average frequency deviation. Based on the average frequency deviation, the synchronization head signal of the received signal after the first correction is corrected. Based on the corrected signal, the MCMA algorithm is used again for the second equalization calculation. During the second equalization, the value of the memory factor is reduced. After the two equalization calculations, it can resist large frequency deviation and noise.

[0049] Specifically, the data is sorted by time, and unstable data at the beginning of a hop is removed. The stabilized data is then divided into two segments with the same duration. The first phase vector of the later segment is averaged with the second phase vector of the earlier segment to obtain the phase difference. The average frequency offset is calculated based on the phase difference. The received signal synchronization header data is then corrected a second time based on the average frequency offset. A second synchronization header memory factor is set for the corrected received signal, and a second equalization calculation is performed to resist noise in the received signal.

[0050] After the above training process, the data range of the first synchronization head memory factor and the data range of the second synchronization head memory factor are obtained.

[0051] The one-hop signal at the receiving end is processed based on the first synchronization head memory factor and the second synchronization head memory factor.

[0052] After receiving a hop of data, the receiving end rotates the synchronization header data in the received signal of this hop, and then combines the rotated synchronization header data with the service data in the same hop to form joint data. Based on the first synchronization header memory factor, the first memory factor is set, and the third equalization calculation is performed. The weighted vector of the received signal is iterated, and each calculation yields a series of calculation results. The maximum value and the phase corresponding to the maximum value in the calculation results are obtained and stored.

[0053] After multiple iterative calculations of the weighted vectors, a set of phase data is obtained, forming a second phase vector group. The phase data is sorted by time, and the phase difference of the phase vectors is calculated. The average frequency offset of the joint data is calculated based on the phase difference. The received signal after the first correction is corrected a second time based on the average frequency offset of the joint data. For the received signal after the second correction, a second memory factor is set, and a fourth equalization calculation is performed to obtain a precise received signal.

[0054] In one specific embodiment of this application, the receiving end performs sliding synchronization on the received signal, finds the synchronization header data in each hop signal, calculates the initial frequency offset, i.e. the first frequency offset Δf1, which is a coarse frequency offset, and performs the first correction on the received signal.

[0055] Even after the first correction, the received signal still has a residual frequency offset, known as the first residual frequency offset, f. res1The range is narrowed due to the correction, to approximately 500Hz to 100Hz, i.e., f res1 =f doppler The value of -Δf1 is between 500Hz and 100Hz, where f doppler This represents the true frequency offset of the received signal. The residual frequency offset differs at different signal-to-noise ratios.

[0056] Further narrow the residual frequency offset range to minimize the frequency offset of the received signal.

[0057] Calculate the average frequency offset of the synchronization header data:

[0058] Rotate the synchronization header data by 45 degrees to change its phase, making it easier to perform calculations in conjunction with business data.

[0059] The rotated synchronization header data is subjected to equalization calculation using the Modified Constant Modulus Algorithm (MCMA). The cost function in the MCMA consists of real and imaginary parts, which can compensate for phase errors. The cost function is as follows:

[0060] e(k) = e R (k)+je I (k) (1);

[0061]

[0062]

[0063] In the formula, k represents the input signal index, the subscript R represents the real part of the signal, the subscript I represents the imaginary part of the signal, and the constant modulus is:

[0064]

[0065]

[0066] In the formula, E[] represents the expected operation, α() represents the symbol of the transmitted data after modulation and mapping, and W corrects the input signal X:

[0067] y(k)=X T (k)·W(k) (6);

[0068] In the formula, T represents the transpose operation, and the input vector is X(k):

[0069] X(k) = [x(k), ..., x(k-N+1)] T (7);

[0070] In the formula, N represents the length of W.

[0071] Weighted vector W(k):

[0072] W(k) = [w0(k), ..., w N-1 (k)] T (8);

[0073] The iterative formula for the weighted vector is:

[0074] W(k+1)=W(k)-μ·e(k)·X * (k) (9);

[0075] In the formula, μ represents the memory factor, and "*" represents the conjugate operation.

[0076] Ideally, the difference between Formula 2 and Formula 3 is zero, that is... At this point, the phase error is zero, meaning there is no phase error.

[0077] However, phase error does exist in reality.

[0078] By adjusting the memory factor to counteract interference from large frequency offsets, the smaller the memory factor, the better the noise immunity, but the inability to track rapidly changing signals. Therefore, the initial value of the first memory factor is relatively large, which is [1 / (2^5), 1 / (2^6)], that is, 1 / 5 of 2 or 1 / 6 of 2.

[0079] According to equation (9), each iteration of the weighted vector calculation will yield a series of calculation results, from which the maximum value W(k) is obtained. max =MAX[W(k)], calculates the maximum value W(k). max The phase θ(k) is obtained and stored:

[0080] θ(k)=angle(W(k) max (10);

[0081] For different synchronization head input signals in a hop signal, the vector iteration is calculated according to Equation (9), and the corresponding phase is calculated according to Equation (10).

[0082] After multiple calculations, a series of phase values ​​are obtained, forming the first set of phase vector signals θ_List1:

[0083] θ_List1=[θ1(1), θ1(2), ...θ1(Ls+Ld) (11);

[0084] Based on the time of each phase in the phase vector signal, the frequency offset caused by time change is calculated. The average value of all frequency offsets in the phase vector group is obtained to get the average frequency offset of the synchronization header data. Based on the average frequency offset of the synchronization header data, the synchronization header signal of the received signal after the first correction is corrected. Based on the corrected signal, the MCMA algorithm is used again for the second equalization calculation. During the second equalization, the value of the memory factor is reduced. In this application, the value of the second memory factor is [1 / (2^7), 1 / (2^8)].

[0085] After secondary equalization calculations, it can resist large frequency deviations and noise.

[0086] Simultaneously calculate the average frequency offset for both the synchronization header data and the business data:

[0087] Rotate the synchronization header data in the first-hop received signal so that the phase of the service data in the current-hop received signal and the synchronization header data are in the same quadrant.

[0088] Specifically, rotate the synchronization header data by 45 degrees, such as... Figure 2 As shown in the figure, 1 represents the phase of the synchronization head data when it is not rotated, and 2 represents the phase of the synchronization head data after rotation and the phase of the service data. The two are located in the same phase interval. The rotated synchronization head data and the service data are used together for the second frequency offset calculation.

[0089] The rotated synchronization header data is combined with the business data, and a modified constant modulus algorithm is used, including formulas 1 to 11, to perform the first balance calculation on the combined data.

[0090] In the first equalization calculation of the joint data, similarly, the memory factor is adjusted to combat interference with large frequency offsets. The smaller the memory factor, the better the noise immunity, but it cannot track rapidly changing signals. Therefore, the memory factor is set to a relatively large value initially, which is [1 / (2^5), 1 / (2^6)], that is, 1 / 5 of 2 or 1 / 6 of 2.

[0091] After a series of operations, a series of phase values ​​are obtained, forming the second set of phase vector signals θ_List2:

[0092] θ_List2=[θ2(1), θ2(2), ...θ2(Ls+Ld) (12);

[0093] Based on the time of each phase in the phase vector signal, the frequency offset caused by time change is calculated. The average value of all frequency offsets in the phase vector group is obtained to obtain the average frequency offset of the joint data. The received signal after the first correction is corrected based on the average frequency offset of the joint data. Based on the corrected signal, the MCMA algorithm is used again for the second equalization calculation. During the second equalization, the value of the memory factor is reduced. In this application, the value of the second memory factor is [1 / (2^7), 1 / (2^8)].

[0094] In one specific embodiment of this application, to prevent the data from being unstable in the initial stage of MCMA training, signal data from the previous period is removed, and the number of signals in the phase vector group is reduced accordingly, resulting in the third group of phase vector signals θ_List3:

[0095] θ_List3=[θ(Ls+1), θ(Ls+2), ...θ(Ls+Ld) (13);

[0096] Following the chronological order, the third set of phase vector signals is divided into two parts. The phase difference between the second time interval and the first time interval is averaged to obtain the average phase difference Δθ.

[0097]

[0098] Calculate the average frequency offset, i.e., the second frequency offset Δf2, based on the average phase difference Δθ:

[0099]

[0100] In the formula, f b This represents the symbol rate of the physical layer.

[0101] Based on the first and second frequency offsets, the second residual frequency offset f is calculated. res2

[0102] f res2 =f doppler -(Δf1+Δf2) (16);

[0103] The first frequency offset correction is used to obtain the first corrected received signal. Then, MCMA equalization is performed on the first corrected received signal. At this time, the memory factor is set to be relatively large. The second frequency offset is calculated and the first corrected received signal is corrected for the second frequency offset. The second corrected received signal obtained after the second frequency offset correction is performed again. At this time, the memory factor is set to be relatively small to obtain the accurately corrected received signal.

[0104] Simulations were performed at different signal-to-noise ratios (SNR) to calculate the first and second residual frequency offsets, respectively. Figure 3 As shown, when SNR=3, the first residual frequency deviation is 250Hz, while the second residual frequency deviation is 50Hz, which greatly reduces the frequency deviation range.

[0105] First, the synchronization header data is rotated to align with the phase of the service data in the same quadrant. Then, the first MCMA equalization operation is performed on the rotated synchronization header data, with the memory factor set relatively large. The average frequency offset of the synchronization header data is calculated, and the frequency offset of the received signal after the first correction is corrected to obtain the second corrected data. The second MCMA operation is then performed on the second corrected data to obtain the corrected data. During this process, the memory factor is trained.

[0106] Based on the trained memory factor, the rotated synchronization header data is combined with the service data to perform the first MCMA equalization operation on the combined data. The memory factor is then adjusted, the average frequency offset of the combined data is calculated, and the frequency offset of the received signal after the second correction is corrected to obtain the third corrected data. The third corrected data is then subjected to the fourth MCMA operation to obtain the finely corrected data, further reducing the residual frequency offset.

[0107] This application discloses a method for calculating frequency offset in a high-frequency, high-speed frequency hopping system, including the receiver calculation process, as follows: Figure 4 As shown, it includes the following steps:

[0108] S1. The receiving end generates a local signal training sequence and simultaneously receives a one-hop signal;

[0109] S2. Perform sliding synchronization on the received one-hop signal, find the synchronization head, calculate the initial frequency offset, and perform the first correction on the received signal based on the initial frequency offset to obtain the first corrected received signal.

[0110] S3. Perform PI / 4 rotation on the synchronization header data of the received signal so that the phase of the synchronization header data and the phase of the service data are in the same quadrant. Perform the first equalization calculation and set the first memory factor to be relatively large during the calculation.

[0111] S4. Perform the first equalization calculation on an input signal to obtain multiple weighted vector iteration values. Find the maximum value of the weighted vector iteration values, calculate the phase corresponding to the maximum value, and store them.

[0112] S5. Perform the first equalization calculation on different input signals to obtain a series of phase values ​​and form a phase vector signal group;

[0113] S6. Calculate the frequency offset of the phase vector signal between adjacent time intervals based on the time corresponding to different input signals;

[0114] S7. Calculate the average value of all frequency offsets to obtain the average frequency offset;

[0115] S8. Based on the average frequency offset, the received signal after the first correction is corrected to obtain the corrected signal;

[0116] S9. For the corrected signal, set the memory factor to be relatively small and perform a second equalization calculation to obtain a precise received signal.

[0117] Using this method, a secondary equalization calculation is performed after rotating the synchronization header data; or the synchronization header data is rotated and then combined with service data for a secondary equalization calculation; or the synchronization header data is rotated first and then a secondary equalization calculation is performed to obtain the range of memory factor values, and then the rotated synchronization header data is combined with service data for a secondary equalization calculation to obtain an accurate received signal.

[0118] After secondary frequency offset correction, the business data is simulated, such as... Figure 5 As shown, it can be seen that when there is a large frequency offset, the MCMA equalized QPSK signal is very close to the theoretical curve.

[0119] This application discloses a frequency offset calculation terminal device in a high-frequency, high-speed frequency hopping system. The terminal device of this embodiment includes: a processor, a memory, and a computer program stored in the memory and executable on the processor, such as an equalization calculation program. When the processor executes the computer program, it implements the method described in this application.

[0120] For example, the computer program can be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units can be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program in the frequency offset calculation terminal device of the high-frequency, high-speed frequency hopping system. For example, the computer program can be divided into multiple modules, each with the following specific functions:

[0121] 1. Synchronization head data rotation module, used to perform phase rotation on the synchronization head data;

[0122] 2. Equalization calculation module, used to perform equalization calculations on the input signal.

[0123] The frequency offset calculation terminal device in the high-frequency, high-speed frequency hopping system can be a desktop computer, laptop, handheld computer, or cloud server, etc. The frequency offset calculation terminal device in the high-frequency, high-speed frequency hopping system may include, but is not limited to, a processor and memory. Those skilled in the art will understand that the above examples are merely examples of the frequency offset calculation terminal device in the high-frequency, high-speed frequency hopping system and do not constitute a limitation on the frequency offset calculation terminal device in the high-frequency, high-speed frequency hopping system. It may include more or fewer components, or combine certain components, or different components. For example, the frequency offset calculation terminal device in the high-frequency, high-speed frequency hopping system may also include input / output devices, network access devices, buses, etc.

[0124] The processor 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. The general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the frequency offset calculation terminal device in the high-frequency, high-speed frequency hopping system, connecting various parts of the frequency offset calculation terminal device through various interfaces and lines.

[0125] The memory can be used to store the computer programs and / or modules. The processor, by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory, realizes various functions of the frequency offset calculation terminal device in the high-frequency high-speed frequency hopping system. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created according to the use of the mobile phone (such as audio data, phonebook, etc.). In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital card (SD) card, flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0126] The module / unit integrated in the frequency offset calculation terminal device of the high-frequency high-speed frequency hopping system described above, if implemented as a software functional unit and sold or used as an independent product, 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 of the present invention 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 includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the 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.

[0127] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for calculating frequency offset in a high-frequency, high-speed frequency hopping system, characterized in that: This includes, at the receiving end, performing a first correction on the received signal based on the first frequency offset, rotating the synchronization header data of the received signal so that the phase of the rotated synchronization header data is in the same quadrant as the phase of the service data, performing a first equalization calculation on the rotated synchronization header data to obtain the average frequency offset of the synchronization header, performing a second correction on the received data after the first correction to obtain the corrected data, and performing a second equalization calculation on the corrected data to obtain a precise received signal. The modified constant modulus algorithm is used for equalization calculation. The equalization calculation is performed on one input signal in the one-hop received signal to obtain multiple weighted vector iteration values. The maximum value of the weighted vector iteration is obtained, and the phase vector is calculated. Remove the first segment of data from the first hop signal, calculate the phase vector of the second segment of data to obtain the third set of phase vectors, divide the second segment of data into the first part and the second part according to time, calculate the average phase difference between the phase vector of the second part and the phase vector of the first part, and calculate the average frequency deviation based on the average phase difference. The third set of phase vectors is shown below: ； Following the chronological order, the third set of phase vector signals is divided into two parts. The phase difference between the second time interval and the first time interval is averaged to obtain the average phase difference. The length of the service data for the one-hop signal generated by the transmitter is Ld, and the length of the synchronization header data is Ls. ； Based on the average phase difference Calculate the average frequency offset, i.e., the second frequency offset. : ； In the formula, Indicates the symbol rate of the physical layer; The second residual frequency offset is calculated based on the first and second frequency offsets. ; ； In the formula, This indicates the true frequency offset of the received signal. This indicates the first frequency offset.

2. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 1, characterized in that: Rotate the synchronization header data by PI / 4, i.e., 45 degrees; during the first equalization calculation, set the memory factor value to be greater than the memory factor value set during the second equalization calculation.

3. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 2, characterized in that: In the first balancing calculation, the memory factor is set to 1 / (2^5) or 1 / (2^6), and in the second balancing calculation, the memory factor is set to 1 / (2^7) or 1 / (2^8).

4. A frequency offset calculation terminal in a high-frequency, high-speed frequency hopping system, 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 method as described in any one of claims 1-3.

5. A method for calculating frequency offset in a high-frequency, high-speed frequency hopping system, characterized in that: This includes, at the receiving end, performing a first correction on the received signal based on the first frequency offset, rotating the synchronization header data of the received signal so that the phase of the rotated synchronization header data is in the same quadrant as the phase of the service data, combining the rotated synchronization header data with the service data, performing a first equalization calculation on the combined data to obtain the average frequency offset of the combined data, performing a second correction on the received data after the first correction based on the average frequency offset of the combined data to obtain the corrected data, and performing a second equalization calculation on the corrected data to obtain an accurate received signal; The modified constant modulus algorithm is used for equalization calculation. The equalization calculation is performed on one input signal in the one-hop received signal to obtain multiple weighted vector iteration values. The maximum value of the weighted vector iteration is obtained, and the phase vector is calculated. Remove the first segment of data from the first hop signal, calculate the phase vector of the second segment of data to obtain the third set of phase vectors, divide the second segment of data into the first part and the second part according to time, calculate the average phase difference between the phase vector of the second part and the phase vector of the first part, and calculate the average frequency deviation based on the average phase difference. The third set of phase vectors is shown below: ； Following the chronological order, the third set of phase vector signals is divided into two parts. The phase difference between the second time interval and the first time interval is averaged to obtain the average phase difference. The length of the service data for the one-hop signal generated by the transmitter is Ld, and the length of the synchronization header data is Ls. ； Based on the average phase difference Calculate the average frequency offset, i.e., the second frequency offset. : ； In the formula, Indicates the symbol rate of the physical layer; The second residual frequency offset is calculated based on the first and second frequency offsets. ; ； In the formula, This indicates the true frequency offset of the received signal. This indicates the first frequency offset.

6. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 5, characterized in that: Rotate the synchronization header data by PI / 4, i.e., 45 degrees; during the first equalization calculation, set the memory factor value to be greater than the memory factor value set during the second equalization calculation.

7. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 6, characterized in that: In the first balancing calculation, the memory factor is set to 1 / (2^5) or 1 / (2^6), and in the second balancing calculation, the memory factor is set to 1 / (2^7) or 1 / (2^8).

8. A frequency offset calculation terminal in a high-frequency, high-speed frequency hopping system, 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 method as described in any one of claims 5-7.

9. A method for calculating frequency offset in a high-frequency, high-speed frequency hopping system, characterized in that: This includes, at the receiving end, performing a first correction on the received signal based on the first frequency offset, rotating the synchronization header data of the received signal so that the phase of the rotated synchronization header data is in the same quadrant as the phase of the service data, performing a first equalization calculation on the rotated synchronization header data to obtain the average frequency offset of the synchronization header, performing a second correction on the received data after the first correction to obtain the corrected synchronization header data, performing a second equalization calculation on the corrected synchronization header data, and obtaining the range of memory factor values ​​after the two equalization calculations. The rotated synchronization head data is combined with the service data. Based on the range of memory factor values, the combined data is subjected to a first equalization calculation to obtain the average frequency offset of the combined data. Based on the average frequency offset of the combined data, the received data after the first correction is subjected to a second correction to obtain the received signal correction data. The received signal correction data is subjected to a second equalization calculation to obtain an accurate received signal.

10. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 9, characterized in that: Rotate the synchronization header data by PI / 4, i.e., 45 degrees; during the first equalization calculation, set the memory factor value to be greater than the memory factor value set during the second equalization calculation.

11. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 10, characterized in that: In the first balancing calculation, the memory factor is set to 1 / (2^5) or 1 / (2^6), and in the second balancing calculation, the memory factor is set to 1 / (2^7) or 1 / (2^8).

12. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 9, characterized in that: The modified constant modulus algorithm is used for equalization calculation. The equalization calculation is performed on one input signal in the one-hop received signal to obtain multiple weighted vector iteration values. The maximum value of the weighted vector iteration is obtained, and the phase vector is calculated.

13. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 12, characterized in that: Equalization calculations are performed on different input signals to obtain three sets of phase vectors. The phase difference between adjacent time phase vectors is calculated based on the corresponding time of the input signal. The frequency offset is calculated based on the phase difference. The average frequency offset is obtained by averaging all frequency offsets. The received signal after the first correction is corrected based on the average frequency offset to obtain the corrected data.

14. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 12, characterized in that: Remove the first segment of data from the first hop signal, calculate the phase vector of the second segment of data to obtain the third set of phase vectors, divide the second segment of data into the first part and the second part according to time, calculate the average phase difference between the phase vector of the second part and the phase vector of the first part, and calculate the average frequency offset based on the average phase difference.

15. The method for calculating frequency offset in a high-frequency, high-speed frequency hopping system according to claim 14, characterized in that: The third set of phase vectors is shown below: ； Following the chronological order, the third set of phase vector signals is divided into two parts. The phase difference between the second time interval and the first time interval is averaged to obtain the average phase difference. The length of the service data for the one-hop signal generated by the transmitter is Ld, and the length of the synchronization header data is Ls. ； Based on the average phase difference Calculate the average frequency offset, i.e., the second frequency offset. : ； In the formula, Indicates the symbol rate of the physical layer; Based on the first and second frequency offsets, the second residual frequency offset f_res2 is calculated; ； In the formula, This indicates the true frequency offset of the received signal. This indicates the first frequency offset.

16. A frequency offset calculation terminal in a high-frequency, high-speed frequency hopping system, 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 method as described in any one of claims 9-15.

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