Satellite navigation signal tracking method and apparatus, and electronic device and readable storage medium

Abstract

Provided in the present application are a satellite navigation signal tracking method and apparatus, and an electronic device and a readable storage medium. The method comprises: generating a local satellite navigation signal according to a lookup table and the current multi-branch local satellite navigation signal; performing operation processing on the local satellite navigation signal and a digital intermediate-frequency satellite navigation signal, so as to obtain a plurality of paths of energy values; performing accumulation calculation on the plurality of paths of energy values, and inputting an accumulation calculation result into a carrier loop and / or a code loop; and tracking a satellite navigation signal according to the carrier loop and / or the code loop. In the present application, a local satellite navigation signal is generated by means of a lookup table and the current multi-branch local satellite navigation signal, a series of operation processing is performed on the local satellite navigation signal and a digital intermediate-frequency satellite navigation signal, and a calculation result is then inputted into a carrier loop and / or a code loop, so as to track a satellite navigation signal when a front-end bandwidth is sufficient; and the entire tracking method involves low implementation complexity, a simple processing process and easy implementation.

Description

Satellite navigation signal tracking method, device, electronic device and readable storage medium

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application number 2023106811466, filed with the Chinese Patent Office on June 9, 2023, entitled “Satellite navigation signal tracking method, device, electronic device and readable storage medium,” the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of satellite navigation, and more specifically, to a satellite navigation signal tracking method, device, electronic device, and readable storage medium. Background Art

[0004] Satellite navigation and positioning technology is finding increasingly widespread application. However, in practice, satellite signal obstructions often occur, causing a sharp drop in the signal CN0 (i.e., the carrier-to-noise power spectral density ratio) or even the inability to receive the signal. Therefore, real-time tracking of satellite navigation signals is necessary to prevent these situations. However, tracking satellite navigation signals is currently difficult even with sufficient front-end bandwidth.

[0005] Summary of the Invention

[0006] In view of this, the purpose of the embodiments of the present application is to provide a satellite navigation signal tracking method, device, electronic device and readable storage medium, which can stably track satellite navigation signals when the front-end bandwidth is sufficient.

[0007] In a first aspect, an embodiment of the present application provides a satellite navigation signal tracking method, comprising: generating a local satellite navigation signal based on a lookup table and current multi-branch local satellite navigation signals; performing calculations on the local satellite navigation signal and a digital intermediate frequency satellite navigation signal to obtain multi-channel energy values; accumulating the multi-channel energy values ​​and inputting the accumulated calculation results into a carrier loop and / or a code loop; and tracking the satellite navigation signal based on the carrier loop and / or the code loop.

[0008] In the above implementation, a local satellite navigation signal is generated using a lookup table. This signal is then processed based on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal before being input into the carrier loop and / or code loop. Because the local navigation signal is generated using a pre-established lookup table, it is unaffected by other factors. This allows tracking of satellite navigation signals when there is sufficient front-end bandwidth. The entire tracking method is low in complexity, simple in processing, and easy to implement.

[0009] In some embodiments, generating a local satellite navigation signal based on a lookup table and a current multi-branch local satellite navigation signal includes: obtaining pseudocode information of multiple branches of the current multi-branch local satellite navigation signal, and telegrams or secondary code information of multiple branches; searching for the pseudocode information and the current signal parameters corresponding to the telegram or the secondary code information in the lookup table; and generating a local satellite navigation signal based on the current signal parameters, the pseudocode information, and the telegram or the secondary code information.

[0010] In the above implementation, based on the pseudocode information of multiple branches of the current multi-branch local satellite navigation signal and the telegram or secondary code information, the current signal parameters can be determined in a lookup table to locally generate satellite navigation information. The locally generated satellite navigation information is then adjusted based on the pseudocode information and the telegram or secondary code information to obtain the final local satellite navigation signal. Because the local satellite navigation signal can be generated using the above method, multiple types of digital intermediate frequency satellite navigation signals can be processed using the local satellite navigation information, thereby achieving tracking of multiple types of satellite navigation signals.

[0011] In some embodiments, a telegram is modulated on the signals of a part of the multiple branches, and a secondary code is modulated on the signals of another part of the branches. The searching for the pseudocode information and the current signal parameters corresponding to the telegram or the secondary code information in the lookup table includes: multiplying or XORing the pseudocode information of each branch with the telegram or the secondary code corresponding to the branch according to the modulation information of the current multi-branch local satellite navigation signal; inputting the result of the multiplication or XOR processing into the lookup table; and searching for the pseudocode information and the current signal parameters corresponding to the telegram or the secondary code information in the lookup table.

[0012] In the above implementation process, by multiplying or XORing the pseudo-code information of each branch with the telegram or secondary code corresponding to the branch, the influence of the telegram or secondary code on the table lookup can be removed, thereby making the information of each branch in the lookup table more correct and improving the accuracy of the table lookup.

[0013] In some embodiments, before generating a local satellite navigation signal based on the current signal parameters, the pseudocode information, and the telegram or the secondary code information, the method further includes: obtaining an intercepted code phase in the pseudocode information; inputting the intercepted code phase into the lookup table; and adjusting the pseudocode information and the current signal parameters corresponding to the telegram or the secondary code information according to the intercepted code phase.

[0014] In the above implementation process, by inputting the intercepted code phase into the lookup table, the current signal parameters matched by the intercepted code phase can be further adjusted so that the generated current signal parameters are more consistent with the actual values ​​of the local satellite navigation signal, thereby improving the accuracy of the local satellite navigation signal.

[0015] In some embodiments, the obtaining of pseudocode information of multiple branches of the current multi-branch local satellite navigation signal includes: generating pseudocode information of multiple branches of the current multi-branch local satellite navigation signal through a multi-bit linear shift register, wherein the multi-bit linear shift register is a multi-bit register unit; or generating pseudocode information of multiple branches of the current multi-branch local satellite navigation signal through a storage code generating unit, wherein the storage code generating unit is configurable.

[0016] In the above implementation, the current multi-branch local satellite navigation signal is generated by a multi-bit linear shift register or a storage code generation unit. Since the multi-bit linear shift register is a multi-bit register, it can process a variety of satellite navigation signals and generate corresponding pseudocode information. Since the storage code generation unit is configurable, it can be configured according to different actual situations, thereby being applicable to the generation of pseudocodes for a wider range of satellite navigation signals and expanding the application scenarios of pseudocode generation.

[0017] In some embodiments, performing operation processing on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values ​​includes: performing demodulation or despreading operation on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values.

[0018] In the above implementation process, by demodulating or despreading the local satellite navigation signal and the intermediate frequency satellite navigation signal, the influence of the carrier, telegram or secondary code on the table lookup can be removed, thereby making the information of each branch in the lookup table more correct, thereby improving the accuracy of the table lookup.

[0019] In some embodiments, the accumulating calculation of the multiple energy values ​​and inputting the accumulated calculation results into the carrier ring and / or code ring includes: performing coherent accumulation calculation and / or incoherent accumulation calculation on the multiple energy values, and inputting the accumulated calculation results into the carrier ring and / or code ring.

[0020] In the above implementation, by performing coherent accumulation calculations on multiple energy values, since this coherent accumulation calculation directly adds the amplitudes of multiple energy values, the temporal continuity of the carrier phase can be maintained, and the signal-to-noise ratio can be improved through amplitude superposition. In addition, by performing incoherent accumulation calculations on multiple energy values, since this incoherent accumulation calculation discards the information of the complex signal and only retains the modulus value, without strict phase relationship restrictions, the application scenarios of this multi-channel energy value calculation can be expanded.

[0021] In some embodiments, before performing operation processing on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values, the method also includes: down-converting the processed satellite navigation signal and the local carrier signal to obtain a digital zero intermediate frequency satellite navigation signal; performing operation processing on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values ​​includes: performing operation processing on the local satellite navigation signal and the digital zero intermediate frequency satellite navigation signal to obtain multiple energy values.

[0022] In the above implementation process, by converting the digital intermediate frequency signal into a digital zero intermediate frequency signal, the carrier in the digital intermediate frequency signal can be removed, thereby improving the quality and reliability of the digital intermediate frequency signal.

[0023] In the second aspect, an embodiment of the present application also provides a signal tracking device, including: a generation module, configured to generate a local satellite navigation signal based on a lookup table and current multi-branch local satellite navigation signals; a processing module, configured to perform calculations on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values; a calculation module, configured to accumulate the multiple energy values ​​and input the accumulated calculation results into a carrier loop and / or a code loop; a tracking module, configured to track the satellite navigation signal based on the carrier loop and / or the code loop.

[0024] In a third aspect, an embodiment of the present application further provides an electronic device comprising: a processor and a memory, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the machine-readable instructions are executed by the processor to perform the steps of the method in the above-mentioned first aspect, or any possible implementation of the first aspect.

[0025] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the satellite navigation signal tracking method according to the above-mentioned first aspect or any possible implementation of the first aspect are executed.

[0026] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the following embodiments are given in conjunction with the accompanying drawings for detailed description as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0028] FIG1 is a flow chart of a satellite navigation signal tracking method provided by an embodiment of the present application;

[0029] FIG2 is a schematic diagram of generating a local satellite navigation signal according to an embodiment of the present application;

[0030] FIG3 is a schematic diagram of generating a digital zero-IF signal according to an embodiment of the present application;

[0031] FIG4 is a schematic diagram of a complete feedback loop of a satellite navigation signal tracking method according to an embodiment of the present application;

[0032] FIG5 is a schematic diagram of the functional modules of a satellite navigation signal tracking device provided in an embodiment of the present application;

[0033] FIG6 is a block diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application.

[0035] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0036] The Galileo system is a satellite navigation and positioning system jointly developed by the European Union and the European Space Agency. The current Galileo system is mainly divided into three frequency bands: E1, E5, and E6. Galileo's E5 band signal is transmitted using AltBOC (Alternate Binary Offset Carrier). Compared to receiving and processing only one signal, this signal is 6dB stronger. This strong signal can effectively improve the problem of signal loss caused by signal obstruction. Furthermore, by using the full-band AltBOC reception method, the pseudo-code accuracy and anti-multipath effect of baseband tracking are significantly higher than those of BPSK (Binary Phase Shift Keying) signals under the same conditions.

[0037] The inventors of this application have discovered through extensive research that it is currently difficult to track satellite navigation signals, such as AltBOC and AltBOC-like signals, even with sufficient front-end bandwidth. Currently, there are few methods for directly receiving and processing full-bandwidth AltBOC and AltBOC-like signals, making tracking them difficult.

[0038] In view of this, the inventors of the present application propose a satellite navigation tracking method, which generates a local satellite navigation signal by looking up a table and the current multi-branch local satellite navigation signal, and inputs the local satellite navigation signal and the digital intermediate frequency satellite navigation signal into the carrier loop and / or code loop after a series of operations, thereby realizing the tracking of the satellite navigation signal when the front-end bandwidth is sufficient. The entire satellite navigation signal tracking method has low implementation complexity, a simple processing process, and is easy to implement.

[0039] Please refer to Figure 1, which is a flow chart of a satellite navigation signal tracking method provided by an embodiment of the present application. The specific process shown in Figure 1 will be described in detail below.

[0040] Step 201: Generate a local satellite navigation signal according to a lookup table and current multi-branch local satellite navigation signals.

[0041] The lookup table here is a table that shows the relationship between satellite navigation signals and their signal parameters. This lookup table includes each satellite navigation signal and its corresponding signal parameters, such as phase and amplitude. This lookup table can be pre-established. For example, a lookup table corresponding to AltBOC or AltBOC-like signals can be configured during system initialization. When using this lookup table, the pseudocode and secondary code information of the satellite navigation signal can be used to search for the corresponding signal parameters in the lookup table.

[0042] The above-mentioned current multi-branch local satellite navigation signals are satellite navigation signals of multiple branches obtained locally at the current moment.

[0043] In some embodiments, the current multi-branch local satellite navigation signal is a satellite navigation signal adjusted by a carrier loop or a code loop at the current moment.

[0044] It can be understood that when generating a local satellite navigation signal, the pseudocode information and / or telegram or secondary code information of the current multi-branch local satellite navigation signal can be used first, and based on the pseudocode information and / or telegram or secondary code information, the corresponding signal parameters can be searched in the lookup table, and finally the local satellite navigation signal can be generated based on the found signal parameters, pseudocode information and / or telegram or secondary code information.

[0045] Step 202 : Perform calculations on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values.

[0046] It is understood that after the satellite navigation signal is received by the antenna, it undergoes RF processing and AD sampling to obtain a digital intermediate frequency satellite navigation signal. The digital intermediate frequency satellite navigation signal obtained after AD sampling is processed with the local satellite navigation signal to obtain the baseband I and Q components.

[0047] The multi-path energy values ​​here may include the I component and the Q component. The I component and the Q component may form a set of IQ energy values.

[0048] In some embodiments, after the digital intermediate frequency satellite navigation signal is determined, the digital intermediate frequency satellite navigation signal may be down-converted to obtain a digital zero intermediate frequency satellite navigation signal.

[0049] Step 203: Accumulate and calculate the multi-channel energy values, and input the accumulated calculation results into the carrier loop and / or code loop.

[0050] The accumulation calculation here is configured to demodulate the multi-path energy values ​​to restore the modulated signal to the modulated signal. The accumulation calculation may include coherent accumulation calculation and non-coherent accumulation calculation.

[0051] Step 204: Track the satellite navigation signal according to the carrier loop and / or the code loop.

[0052] The carrier loop is configured to track the carrier in the satellite navigation signal, and the code loop is configured to track the pseudo code in the satellite navigation signal.

[0053] The carrier loop is configured to replicate the carrier signal and match the received satellite navigation signal, thereby completely stripping the carrier from the satellite navigation signal through a frequency mixing mechanism. If the replicated carrier signal is inconsistent with the received satellite navigation signal, the carrier in the received signal cannot be completely stripped, meaning the received signal cannot be downconverted to true baseband.

[0054] Typically, to completely remove the carrier from a digital IF signal and downconvert it from the IF to baseband, a carrier loop incorporates a mixer, and the resulting carrier is replicated to maintain consistency with the input carrier. If the carrier loop detects a phase difference between its replicated carrier and the input carrier, it adjusts the phase of the replicated carrier accordingly to maintain phase consistency. If the carrier loop detects a frequency difference between its replicated carrier and the input carrier, it adjusts the frequency of the replicated carrier accordingly to maintain consistency.

[0055] After completely stripping the carrier from the digital IF signal, the carrier loop can obtain the complete navigation message data bits. To organize the navigation message data bits into words, the receiver can also perform bit synchronization and frame synchronization after entering the signal tracking phase to correctly divide the navigation message data bits into structurally meaningful words, thereby obtaining the navigation message parameters.

[0056] Similarly, the code loop is configured so that the copied pseudocode matches the received satellite navigation signal, thus completely stripping the pseudocode from the satellite navigation signal through the mixing mechanism. If the copied pseudocode is inconsistent with the received pseudocode, the pseudocode correlation will be affected, and the signal energy will be significantly weakened.

[0057] To completely remove the pseudo-code from the digital IF signal and downconvert it from the IF to baseband, the carrier loop typically incorporates a mixer, and the resulting pseudo-code is replicated to match the input pseudo-code. If the code loop detects a phase difference between the replicated pseudo-code and the input pseudo-code, it adjusts the phase of the replicated pseudo-code accordingly to maintain phase consistency. If the code loop detects a frequency difference between the replicated pseudo-code and the input pseudo-code, it adjusts the frequency of the replicated pseudo-code accordingly to maintain frequency consistency.

[0058] Optionally, the accumulated calculation results can be input into both the carrier loop and the code loop, allowing satellite navigation signals to be tracked using both loops. Alternatively, the accumulated calculation results can be input into only the carrier loop or only the code loop, allowing satellite navigation signals to be tracked using either loop. The carrier loop and code loop used for satellite navigation information tracking can be adjusted based on actual circumstances and are not specifically limited in this application.

[0059] In the above implementation, a local satellite navigation signal is generated using a lookup table. This signal is then processed based on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal before being input into the carrier loop and / or code loop. Because the local navigation signal is generated using a pre-established lookup table, it is unaffected by other factors. This allows tracking of satellite navigation signals when the front-end bandwidth is sufficient. The entire satellite navigation signal tracking method features low implementation complexity, a simple processing procedure, and ease of implementation.

[0060] In one possible implementation, step 201 includes: obtaining pseudocode information of multiple branches of the current multi-branch local satellite navigation signal, and telegram or secondary code information; searching for the pseudocode information and current signal parameters corresponding to the telegram or secondary code information in a lookup table; and generating a local satellite navigation signal based on the current signal parameters, pseudocode information, and telegram or secondary code information.

[0061] The signals of some of the multiple branches are modulated with a telegram, and the signals of other branches are modulated with a secondary code. Of course, the signals of all of the multiple branches can be modulated with a telegram, or the signals of all of the multiple branches can be modulated with a secondary code. The telegram or secondary code modulated by each of the multiple branches can be adjusted according to actual conditions.

[0062] The multiple branches of the current multi-branch local satellite navigation signal here can be 2 branches, 4 branches, etc. The multiple branches of the current multi-branch local satellite navigation signal can be determined according to actual conditions, and this application does not impose specific restrictions. For example, if the multiple branches of the current multi-branch local satellite navigation signal are 4 branches. The pseudo codes of the 4 branches are E5aI, E5aQ, E5bI and E5bQ respectively. Among them, the E5aI signal and the E5bI signal are modulated with telegrams, and the E5aQ signal and the E5bQ signal are modulated with secondary codes. It can be understood that each branch of the current multi-branch local satellite navigation signal has its corresponding pseudo code information and secondary code information. After processing, the pseudo code information and secondary code information of each branch can be used as input to the lookup table to find the current signal parameters of the local satellite navigation signal.

[0063] In addition, the code phases of the pseudo code and the secondary code may also be used as inputs to the lookup table to adjust the locally generated satellite navigation signal, thereby obtaining the final local satellite navigation signal.

[0064] The above-mentioned current signal parameter can be the current phase or the current amplitude. The specific type of the current signal parameter can be adjusted according to actual conditions, and this application does not impose any specific restrictions.

[0065] In the above implementation, based on the pseudocode information of multiple branches of the current multi-branch local satellite navigation signal and the telegram or secondary code information, the current signal parameters can be determined in a lookup table to locally generate satellite navigation information. The locally generated satellite navigation information is then adjusted based on the pseudocode information and the telegram or secondary code information to obtain the final local satellite navigation signal. Because the local satellite navigation signal can be generated using the above method, multiple types of digital intermediate frequency satellite navigation signals can be processed using the local satellite navigation information, thereby achieving tracking of multiple types of satellite navigation signals.

[0066] In one possible implementation, searching a lookup table for pseudocode information and current signal parameters corresponding to the telegram or secondary code information includes: multiplying or XORing the pseudocode information of each branch with the telegram or secondary code corresponding to the branch based on the modulation information of the current multi-branch local satellite navigation signal; inputting the result of the multiplication or XORing into the lookup table; and searching the lookup table for the pseudocode information and current signal parameters corresponding to the telegram or secondary code information. It is understandable that the current multi-branch local satellite navigation signals are all modulated according to certain modulation rules. When regenerating the local satellite navigation signal, the corresponding branch code can be multiplied or XORed using the secondary code or telegram based on the modulation information of the current multi-branch local satellite navigation signal, thereby stripping off the corresponding modulation information.

[0067] In order to further understand step 201 in the embodiment of the present application, the generation and calculation of pseudo code information and secondary code information of multiple branches are further described below with reference to FIG2 :

[0068] As shown in Figure 2, the numerically controlled oscillator (NCO) code group includes two code groups, code NCO1 and code NCO2. After acquiring the current multi-branch local satellite navigation signal, the multi-rate variation module can configure the corresponding interception code fineness. Then, code NCO1 and code NCO2 are respectively generated by a multi-bit linear shift register code generation unit or a storage code generation unit in a broadband full-state channel and / or broadband pilot channel to generate corresponding pseudocodes.

[0069] The pseudocode generated by the multi-bit linear shift register code production unit or the storage code production unit is multiplied or XORed with the upper sideband I telegram or secondary code, the upper sideband Q telegram or secondary code, the lower sideband I telegram or secondary code, or the lower sideband Q telegram or secondary code, and the processing results are input into a lookup table to determine the corresponding local code information through the lookup table.

[0070] The aforementioned lookup table is a pre-established table that correlates satellite navigation signals with their signal parameters. By inputting the result of multiplication or XOR processing into the lookup table, the corresponding current signal parameters can be directly matched from the table. This lookup table can be flexibly configured during initialization based on different systems, adapting to different systems and input counts.

[0071] Exemplarily, if the input is 2 groups of ALTBOC dual pilot branches and 2 groups of truncated code phases, the lookup table can be configured as a lookup table of the corresponding ALTBOC pilots, and the output is the local codes of the 2 groups of wideband pilot branches.

[0072] If the input is a set of four ALTBOC branches and a set of intercepted code phases, the lookup table can be configured as a lookup table corresponding to the full state of ALTBOC, and the output is a set of local codes for the full broadband signal.

[0073] If the input is two sets of ACE-BOC (Asymmetric Constant Envelope Binary Offset Carrier) two-way pilot branches and two sets of intercepted code phases, the lookup table can be configured as a lookup table of the corresponding ACE-BOC pilots and the corresponding branch power ratios, and the output is the local code of the two sets of wideband pilot branches.

[0074] If the input is a set of four ACE-BOC branches and a set of intercepted code phases, the lookup table can be configured as a lookup table of the corresponding ACE-BOC full state and the corresponding branch power ratio, and the output is a set of local codes for the full broadband signal.

[0075] If the input is two branches of two other signals and two sets of intercepted code phases, the lookup table can be configured as a lookup table of the states of the two branches of the other signals, and the output is the local code of the broadband pilot branch of the two sets of other signals.

[0076] If the input is 4 channels of a group of other signals and a group of intercepted code phases, the lookup table can be configured as a lookup table of the states of the four branches of the other signals, and the output is a group of local codes of a full-bandwidth signal.

[0077] The other signals here are signals other than the above-mentioned ALTBOC, quasi-ALTBOC and ACE-BOC. The above-mentioned pseudo code information includes the pseudo code and the intercepted code phase.

[0078] In some embodiments, when the pseudo code information of the current multi-branch local satellite navigation signal is first obtained, the pseudo code information obtained from other frequency points, the distance and the frequency difference between the frequency points can be used to determine the pseudo code information of each branch of the current multi-branch local satellite navigation signal at the current time point.

[0079] The other frequencies mentioned above are transmitted by the same satellite as the satellite navigation signal to be tracked. Typically, a single satellite can transmit signals at multiple frequencies. For example, Galileo satellites transmit E1, E6, and other signals in addition to E5. To calculate the pseudo-code phase of the E5 signal, the pseudo-code information of E1 at the current time can be calculated. Based on the distance, frequency, and other differences between E1 and E5, the pseudo-code information of E5 at the current time can then be inferred.

[0080] In the above implementation process, by multiplying or XORing the pseudo-code information of each branch with the telegram or secondary code corresponding to the branch, the influence of the telegram or secondary code on the table lookup can be removed, thereby making the information of each branch in the lookup table more correct and improving the accuracy of the table lookup.

[0081] In one possible implementation, before generating a local satellite navigation signal based on current signal parameters, pseudocode information, and telegram or secondary code information, the method further includes: obtaining an intercepted code phase in the pseudocode information; inputting the intercepted code phase into a lookup table; and adjusting the pseudocode information and the current signal parameters corresponding to the telegram or secondary code information based on the intercepted code phase.

[0082] It is understandable that when configuring the lookup table, the truncated code phase precision can be adjusted according to actual conditions. That is, it can be flexibly configured from 1 times the subcarrier width to 1 / N of the subcarrier width, and the value of N can be flexibly configured according to the corresponding system. For example, the configuration number of the ALTBOC signal of the E5 system can be configured to be 1 / 8, 1 / 4, 1 / 2, 1 / 5, 1 / 7, 1 / 3, etc. of the subcarrier code chip width. The configuration number of the ACE-BOC signal of the BDB2 system can be configured to be 1 / 8, 1 / 4, 1 / 2, 1 / 5, 1 / 7, 1 / 3, 1 / 10, 1 / 12, 1 / 13, etc. of the subcarrier code chip width. The truncated code phase precision can be adjusted according to the signal type and actual conditions.

[0083] In some embodiments, the pseudocode information may correspond to multiple signal parameters, and a code phase may be input to intercept the code phase, which may be configured to determine a final current signal parameter from the multiple signal parameters corresponding to the pseudocode information.

[0084] Exemplarily, the lookup table includes multiple rows and multiple columns. The pseudocode information can be configured to determine a corresponding column, wherein the column includes multiple rows, each row corresponding to a signal parameter. The corresponding row value in the column is then determined based on the intercepted code phase. The signal parameter in the row corresponding to the row value is then determined as the current signal parameter. The method for determining the current signal parameter here is exemplary and can be adjusted based on actual circumstances.

[0085] In the above implementation process, by inputting the intercepted code phase into the lookup table, the current signal parameters matched by the intercepted code phase can be further adjusted so that the generated current signal parameters are more consistent with the actual values ​​of the local satellite navigation signal, thereby improving the accuracy of the local satellite navigation signal.

[0086] In one possible implementation, obtaining pseudo code information of multiple branches of the current multi-branch local satellite navigation signal includes: generating pseudo code information of multiple branches of the current multi-branch local satellite navigation signal through a multi-bit linear shift register; or generating pseudo code information of multiple branches of the current multi-branch local satellite navigation signal through a storage code generation unit.

[0087] As can be understood, after acquiring the current multi-branch local satellite navigation signal, a multi-bit linear shift register can be used to generate a pseudocode for the current multi-branch local satellite navigation signal. This multi-bit linear shift register is transformed from a conventional 14-bit shift register unit into a register unit with a larger number of bits, capable of generating longer codes, thereby meeting the pseudocode generation requirements for various satellite navigation signals, such as ALTBOC and ALTBOC-like signals.

[0088] In some embodiments, after acquiring the current multi-branch local satellite navigation signal, the current multi-branch local satellite navigation signal can also generate a nonlinear shift register code through a storage code generation unit. The storage code generation unit can be flexibly configured during initialization to meet the requirements of nonlinear shift register code generation.

[0089] In the above implementation, the current multi-branch local satellite navigation signal is generated by a multi-bit linear shift register or a storage code generation unit. Since the multi-bit linear shift register is a multi-bit register, it can process a variety of satellite navigation signals and generate corresponding pseudocode information. Since the storage code generation unit is configurable, it can be configured according to different actual situations, thereby being applicable to the generation of pseudocodes for a wider range of satellite navigation signals and expanding the application scenarios of pseudocode generation.

[0090] In a possible implementation, step 202 includes: performing a despreading operation on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multi-channel energy values.

[0091] Understandably, when a satellite navigation signal is close to the ground, its signal power is lower than the noise power. By demodulating or despreading the intermediate frequency satellite navigation signal, a spread spectrum gain can be obtained to successfully track the satellite navigation signal. The despreading operation here can be a complex operation.

[0092] The demodulation here is to multiply the carrier of the local satellite navigation signal with the digital intermediate frequency satellite navigation signal, and the despreading is to multiply the local code of the local satellite navigation signal with the digital intermediate frequency satellite navigation signal.

[0093] For example, for the ALTBOC signal of E5, the local satellite navigation signal here can be expressed by the following formula:

[0094] Among them, E5 Altbox is the local satellite navigation signal code, k(t) is the phase, and t is the time.

[0095] For the ACE-BOC signal of BDB2 (Beidou-2, Beidou-2 satellite navigation system), the local satellite navigation signal here can be expressed by the following formula:

[0096] Among them, E5 ACE-VOC is the local satellite navigation signal code, k(t) is the phase, and t is the time.

[0097] It can be understood that the above-mentioned formula of satellite navigation signal is only exemplary. Different satellite navigation signals correspond to different formulas, and this application does not impose any specific limitation.

[0098] In the above implementation process, by performing despreading operations on the local satellite navigation signal and the intermediate frequency satellite navigation signal, the influence of the carrier, telegram or secondary code on the table lookup can be removed, thereby making the information of each branch in the lookup table more correct, thereby improving the accuracy of the table lookup.

[0099] In a possible implementation, step 203 includes: performing coherent accumulation calculation and / or non-coherent accumulation calculation on the multi-channel energy values, and inputting the accumulation calculation results into the carrier loop and / or the code loop.

[0100] Coherent accumulation here involves adding the amplitudes of multiple energy values, which results in noise power accumulation, thereby improving the signal-to-noise ratio. Incoherent accumulation, performed after the signal envelope is taken, discards the complex signal information, retaining only the modulus value and eliminating the strict phase relationship.

[0101] Optionally, the multi-channel energy values ​​can be calculated by both coherent accumulation and incoherent accumulation, or only coherent accumulation, or only incoherent accumulation. The specific calculation method of the multi-channel energy values ​​can be adjusted according to actual conditions, and this application does not make specific restrictions.

[0102] It can be understood that the above coherent accumulation calculation result is input into the carrier loop, and the non-coherent accumulation calculation result is input into the code loop.

[0103] The carrier loop here is configured to adjust the carrier of the satellite navigation signal, and the code loop is configured to adjust the pseudo code of the satellite navigation signal.

[0104] In the above implementation, by performing coherent accumulation calculations on multiple energy values, since this coherent accumulation calculation directly adds the amplitudes of multiple energy values, the temporal continuity of the carrier phase can be maintained, and the signal-to-noise ratio can be improved through amplitude superposition. In addition, by performing incoherent accumulation calculations on multiple energy values, since this incoherent accumulation calculation discards the information of the complex signal and only retains the modulus value, without strict phase relationship restrictions, the application scenarios of this multi-channel energy value calculation can be expanded.

[0105] In one possible implementation, before step 202, the method further includes: down-converting the processed satellite navigation signal and the local carrier signal to obtain a digital zero-IF satellite navigation signal. Step 202 includes: performing computational processing on the local satellite navigation signal and the digital zero-IF satellite navigation signal to obtain multiple energy values.

[0106] The processed satellite navigation signal here refers to a satellite navigation signal that has been processed by radio frequency processing and AD sampling.

[0107] The above-mentioned down-conversion processing is configured to convert the digital intermediate frequency signal into a digital zero intermediate frequency signal. As shown in FIG3 , the specific implementation process of the down-conversion processing can be:

[0108] As shown in FIG3 , after complex multiplication of the processed I signal and Q signal of the satellite navigation signal with the local carrier signal, they can be converted into a zero intermediate frequency I signal and a zero intermediate frequency Q signal.

[0109] The local carrier signal here is generated after the phase is generated by the carrier NCO and the phase-amplitude conversion is completed through the Sin / Cos table.

[0110] The following uses FIG4 as an example to further describe the specific implementation process of the satellite navigation signal tracking method in the embodiment of the present application:

[0111] After acquiring the satellite navigation signal, the antenna performs RF input and AD sampling on it. It then down-converts it with a local carrier signal group (which includes multiple local carrier signals) to produce a digital zero-IF signal. Simultaneously, the pseudo-codes of the in-phase I signal branch, the in-phase Q signal branch, the quadrature I signal branch, and the quadrature Q signal branch from the acquired multi-branch local satellite navigation signal are processed and used as inputs to a lookup table to obtain the local satellite navigation signal. 4 shows that the pseudo-code of the in-phase Q signal branch is multiplied or XORed with the secondary code or message of the in-phase Q signal branch and used as the input of the lookup table; the pseudo-code of the quadrature Q signal branch is multiplied or XORed with the secondary code or message of the quadrature Q signal branch and used as the input of the lookup table; the pseudo-code of the in-phase I signal branch is multiplied or XORed with the secondary code or message of the in-phase I signal branch and used as the input of the lookup table; and the pseudo-code of the quadrature I signal branch is multiplied or XORed with the secondary code or message of the quadrature I signal branch and used as the input of the lookup table. After despreading the digital zero intermediate frequency signal and the local satellite navigation signal, coherent accumulation calculation and / or incoherent accumulation calculation are performed, and the calculation results are input into the carrier loop and / or code loop. The carrier loop and / or code loop are configured to adjust the pseudo-code phase and carrier frequency of the current multi-branch local satellite navigation signal, thereby achieving tracking of the satellite navigation signal.

[0112] It is understood that the processing flow shown in FIG4 is a composite channel processing flow. In actual processing, there are multiple composite channels shown in FIG4, and the composite channels can be flexibly configured according to actual conditions. For example, two broadband pilot signals can be tracked in parallel, or only one broadband full-state signal can be tracked.

[0113] For example, Figure 4 illustrates the processing flow for a processing channel. The carrier NCO group generates one carrier NCO1, which is configured as a wideband full-state channel. The output of the corresponding active code NCO1 in the NCO group is fed to four code generation modules, which generate a truncated code phase. The four generated branch codes and the truncated code phase are then fed into a lookup table corresponding to one ALTBOC full-state channel, capable of processing the full-wideband signal from one satellite. If there are M composite channels, then the wideband full-state signals from M satellites are processed.

[0114] Figure 4 shows a two-channel processing flow. The carrier NCO group generates two carrier NCOs, whose inputs are configured as two wideband pilot channels. The output of code NCO1 in the corresponding code NCO group is fed to two code generation modules, and the output of code NCO2 is fed to two other code generation modules. Codes NCO1 and NCO2 each generate one truncated code phase. The resulting two sets of two branch codes and one truncated code phase are input to a lookup table configured as an ALTBOC wideband pilot lookup table. This allows for parallel processing of two satellite pilot signals. For M composite channels, it processes wideband pilot signals from 2M satellites, thus meeting the requirements of dual-antenna RF input or doubling the number of wideband pilot signal channels. This increases flexibility in adapting to specific scenarios while maintaining the same resources.

[0115] In the above implementation process, by converting the digital intermediate frequency signal into a digital zero intermediate frequency signal, the carrier in the digital intermediate frequency signal can be removed, thereby improving the quality and reliability of the digital intermediate frequency signal.

[0116] Based on the same application concept, the embodiment of the present application also provides a satellite navigation signal tracking device corresponding to the satellite navigation signal tracking method. Since the principle of solving the problem by the device in the embodiment of the present application is similar to that of the aforementioned satellite navigation signal tracking method embodiment, the implementation of the device in this embodiment can refer to the description in the embodiment of the above method, and the repeated parts will not be repeated.

[0117] Please refer to Figure 5, which is a schematic diagram of the functional modules of the satellite navigation signal tracking device provided in an embodiment of the present application. In this embodiment, each module in the satellite navigation signal tracking device is configured to perform each step in the above method embodiment. The satellite navigation signal tracking device includes a generation module 301, a processing module 302, a calculation module 303, and a tracking module 304; wherein,

[0118] The generating module 301 is configured to generate a local satellite navigation signal according to a lookup table and current multi-branch local satellite navigation signals.

[0119] The processing module 302 is configured to perform computation on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values.

[0120] The calculation module 303 is configured to perform cumulative calculation on the multiple energy values ​​and input the cumulative calculation result into the carrier loop and / or the code loop.

[0121] The tracking module 304 is configured to track satellite navigation signals according to the carrier loop and / or the code loop.

[0122] In one possible implementation, the generation module 301 is further configured to: obtain pseudocode information of multiple branches of the current multi-branch local satellite navigation signal, and telegrams or secondary code information of multiple branches; search for the pseudocode information and the current signal parameters corresponding to the telegram or the secondary code information in a lookup table; and generate a local satellite navigation signal based on the current signal parameters, the pseudocode information, and the telegram or the secondary code information.

[0123] In one possible implementation, the generation module 301 is specifically configured to: multiply or XOR the pseudocode information of each branch with the telegram or the secondary code corresponding to the branch according to the modulation information of the current multi-branch local satellite navigation signal; input the result of the multiplication or XOR processing into the lookup table; and search the lookup table for the current signal parameters corresponding to the pseudocode information and the secondary code information.

[0124] In one possible embodiment, the signal tracking device also includes an adjustment module configured to: obtain a truncated code phase in the pseudocode information; input the truncated code phase into the lookup table; and adjust the pseudocode information and the current signal parameters corresponding to the telegram or the secondary code information according to the truncated code phase.

[0125] In one possible implementation, the generation module 301 is specifically configured to: generate pseudocode information of multiple branches of the current multi-branch local satellite navigation signal through a multi-bit linear shift register, where the multi-bit linear shift register is a multi-bit register unit; or generate pseudocode information of multiple branches of the current multi-branch local satellite navigation signal through a storage code generation unit, where the storage code generation unit is configurable.

[0126] In a possible implementation, the processing module 302 is further configured to: perform demodulation or despreading operations on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multi-channel energy values.

[0127] In a possible implementation, the calculation module 303 is further configured to perform coherent accumulation calculation and / or non-coherent accumulation calculation on the multiple energy values, and input the accumulation calculation results into the carrier loop and / or the code loop.

[0128] In a possible implementation, the signal tracking device further includes a preprocessing module configured to perform down-conversion processing on the processed satellite navigation signal and the local carrier signal to obtain a digital zero intermediate frequency satellite navigation signal.

[0129] In a possible implementation, the processing module 302 is specifically configured to: perform computational processing on the local satellite navigation signal and the digital zero intermediate frequency satellite navigation signal to obtain multiple energy values.

[0130] To facilitate understanding of this embodiment, the electronic device that executes the satellite navigation signal tracking method disclosed in the embodiment of the present application is introduced in detail below.

[0131] FIG6 is a block diagram of an electronic device. The electronic device 100 may include a memory 111 and a processor 113. Those skilled in the art will appreciate that the structure shown in FIG6 is merely illustrative and does not limit the structure of the electronic device 100. For example, the electronic device 100 may include more or fewer components than shown in FIG6 , or may have a configuration different from that shown in FIG6 .

[0132] The memory 111 and processor 113 are electrically connected to each other, directly or indirectly, to enable data transmission or interaction. For example, these components may be electrically connected to each other via one or more communication buses or signal lines. The processor 113 is configured to execute the executable modules stored in the memory.

[0133] The memory 111 may be, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), etc. The memory 111 is configured to store a program, and the processor 113 executes the program after receiving an execution instruction. The method executed by the electronic device 100 defined by the process disclosed in any embodiment of the present application may be applied to the processor 113 or implemented by the processor 113.

[0134] The processor 113 may be an integrated circuit chip with signal processing capabilities. The processor 113 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The various methods, steps, and logic block diagrams disclosed in the embodiments of the present application may be implemented or executed. The general-purpose processor may be a microprocessor or any conventional processor.

[0135] The electronic device 100 in this embodiment can be configured to execute each step in each method provided in the embodiments of the present application.

[0136] In addition, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the satellite navigation signal tracking method in the above method embodiment are executed.

[0137] The computer program product of the satellite navigation signal tracking method provided in the embodiment of the present application includes a computer-readable storage medium storing program code. The instructions included in the program code can be configured to execute the steps of the satellite navigation signal tracking method in the above method embodiment. For details, please refer to the above method embodiment and will not be repeated here.

[0138] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions and operations of the devices, methods and computer program products according to the multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, which contains one or more executable instructions configured to implement the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or can be implemented using a combination of dedicated hardware and computer instructions.

[0139] In addition, the functional modules in each embodiment of the present application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0140] If this function is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method of each embodiment of the present application. The aforementioned storage medium includes various media that can store program code, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk. It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0141] The above are merely preferred embodiments of the present application and do not limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included within the scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures.

[0142] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims. Industrial Applicability

[0143] [Corrected 11.07.2024 according to Rule 91] The above scheme is adopted to generate a local satellite navigation signal by using a lookup table and the current multi-branch local satellite navigation signal, and after a series of operations are performed on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal, they are input into the carrier loop and / or code loop to track the satellite navigation signal when the front-end bandwidth is sufficient. The entire tracking method has low implementation complexity, a simple processing process, and is easy to implement.

Claims

1. A satellite navigation signal tracking method, characterized in that: include: Generate a local satellite navigation signal according to the lookup table and the current multi-branch local satellite navigation signal; Performing calculation processing on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multi-channel energy values; Accumulate and calculate the energy values ​​of the multiple channels, and input the accumulated calculation results into the carrier loop and / or the code loop; Satellite navigation signals are tracked according to the carrier loop and / or the code loop.

2. The method according to claim 1, characterized in that The generating of the local satellite navigation signal according to the lookup table and the current multi-branch local satellite navigation signal comprises: Acquire pseudo code information of multiple branches of the current multi-branch local satellite navigation signal, and telegram or secondary code information of multiple branches; Searching the pseudo code information and the current signal parameters corresponding to the telegram or the secondary code information in a lookup table; A local satellite navigation signal is generated according to the current signal parameters, the pseudo code information, and the telegram or the secondary code information.

3. The method according to claim 2, characterized in that The signals of some of the multiple branches are modulated with telegrams, and the signals of the other branches are modulated with secondary codes, and the pseudo code information and the current signal parameters corresponding to the telegram or the secondary code information are searched in the lookup table, including: According to the modulation information of the current multi-branch local satellite navigation signal, the pseudo code information of each branch is multiplied or XORed with the message or the secondary code corresponding to the branch; Inputting the result after multiplication or XOR processing into the lookup table; The pseudo code information and the current signal parameters corresponding to the telegram or the secondary code information are searched in the lookup table.

4. The method according to claim 3, characterized in that Before generating the local satellite navigation signal according to the current signal parameter, the pseudo code information, and the telegram or the secondary code information, the method further includes: Obtaining a truncated code phase in the pseudo code information; inputting the intercepted code phase into the lookup table; The pseudo code information and the current signal parameters corresponding to the telegram or the secondary code information are adjusted according to the intercepted code phase.

5. The method according to claim 2, characterized in that: The acquiring pseudo code information of multiple branches of the current multi-branch local satellite navigation signal includes: Generate pseudo code information of multiple branches of the current multi-branch local satellite navigation signal by a multi-bit linear shift register, wherein the multi-bit linear shift register is a register unit of a multi-digit number; or The pseudo code information of the multiple branches of the current multi-branch local satellite navigation signal is generated by a storage code generating unit, and the storage code generating unit is configurable.

6. The method according to claim 1, characterized in that The processing of the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values ​​includes: The local satellite navigation signal and the digital intermediate frequency satellite navigation signal are demodulated or despread to obtain multi-channel energy values.

7. The method according to claim 1, characterized in that The step of accumulating and calculating the energy values ​​of the multiple paths and inputting the accumulated calculation results into a carrier loop and / or a code loop includes: Coherent accumulation calculation and / or incoherent accumulation calculation are performed on the energy values ​​of the multiple channels, and the accumulation calculation results are input into the carrier loop and / or the code loop.

8. The method according to claim 1, characterized in that Before the local satellite navigation signal and the digital intermediate frequency satellite navigation signal are processed to obtain the multi-channel energy value, the method further includes: Down-converting the processed satellite navigation signal and the local carrier signal to obtain a digital zero intermediate frequency satellite navigation signal; The processing of the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values ​​includes: The local satellite navigation signal and the digital zero intermediate frequency satellite navigation signal are processed to obtain multi-channel energy values.

9. A satellite navigation signal tracking device, characterized in that: include: A generating module, configured to generate a local satellite navigation signal according to the lookup table and the current multi-branch local satellite navigation signal; A processing module configured to perform operation processing on the local satellite navigation signal and the digital intermediate frequency satellite navigation signal to obtain multiple energy values; A calculation module, configured to perform cumulative calculation on the energy values ​​of the multiple channels, and input the cumulative calculation result into a carrier loop and / or a code loop; The tracking module is configured to track the satellite navigation signal according to the carrier loop and / or the code loop.

10. An electronic device, characterized in that: include: A processor and a memory, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the machine-readable instructions are executed by the processor to perform the steps of any method described in claims 1 to 8.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are executed.

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