A Noise-Chirp-like Carrier Phase Estimation Method

Abstract

The present invention provides a noise-like Chirp carrier phase estimation method, the method comprising: a transmitting end obtains a satellite navigation signal based on a noise-like Chirp signal coding modulation; a receiver uses two matching filters with different modulation frequencies to respectively perform time domain search on the satellite navigation signal to obtain a delay frequency offset estimation value; based on the delay frequency offset estimation value, a delay locking tracking loop of the receiver is assisted to lock, and an instant coherent integral of the receiver tracking loop is obtained; the interference term of the instant coherent integral is roughly compensated using the motion information of the carrier to obtain an instant coherent integral after rough compensation; and the instant coherent integral after rough compensation is processed using a Doppler frequency integration method to eliminate the integer ambiguity of the carrier phase to obtain a carrier phase estimation value. The present invention can solve the technical problem that the existing method cannot estimate the accurate carrier phase.

Description

Technical Field

[0001] The present invention relates to the field of satellite navigation technology, and in particular to a noise Chirp-like carrier phase estimation method. Background Art

[0002] In order to obtain centimeter and decimeter-level positioning accuracy, satellite receivers need to use the carrier phase information of navigation signals. However, traditional direct sequence spread spectrum satellite navigation receivers are sensitive to pseudo code-frequency deviation, and require a long pseudo code-frequency deviation two-dimensional search to capture navigation signals in a high dynamic environment.

[0003] At present, the sensitivity of pseudo code-frequency deviation will cause the noise power and unlocking probability of the receiver tracking loop to increase significantly with the improvement of carrier dynamics, which will in turn cause the jump of carrier phase integer count, making it impossible for the receiver to estimate the accurate carrier phase. Summary of the invention

[0004] The present invention provides a noise chirp-like carrier phase estimation method, which can solve the technical problem that the existing method cannot estimate the accurate carrier phase under high dynamic conditions.

[0005] According to one aspect of the present invention, a noise-chirp-like carrier phase estimation method is provided, the method comprising:

[0006] The transmitting end obtains the satellite navigation signal based on the noise-like Chirp signal coding modulation;

[0007] The receiver uses two matched filters with different modulation frequencies to search the satellite navigation signal in the time domain to obtain the estimated value of the delay and frequency offset;

[0008] Based on the estimated value of the time delay and frequency offset, the delay locking tracking loop of the receiver is assisted to lock, and the instant coherent integration of the receiver tracking loop is obtained;

[0009] The interference term of the instantaneous coherent integration is roughly compensated by using the motion information of the carrier, so as to obtain the instantaneous coherent integration after the rough compensation;

[0010] The Doppler frequency integration method is used to process the instantaneous coherent integration after coarse compensation to eliminate the integer ambiguity of the carrier phase and obtain the carrier phase estimation value.

[0011] Preferably, the transmitting end obtains the satellite navigation signal based on the noise-like Chirp signal coding modulation, including:

[0012] A reference Chirp signal is obtained by splicing two Chirp signals with the same symbol duration, the same spectrum width but completely opposite modulation rates, wherein each Chirp signal is spliced ​​by two Chirp signals with the same modulation rate but different starting frequencies;

[0013] Performing noise-like phase modulation on the reference Chirp signal according to the noise-like phase sequence to obtain a noise-like Chirp signal;

[0014] Channel coding the satellite navigation message data to obtain coded navigation message data;

[0015] The coded navigation message data is modulated onto a noise-like Chirp signal to obtain a satellite navigation signal.

[0016] Preferably, the noise-like Chirp signal is obtained by the following formula:

[0017] 0<t<T s ;

[0018] in,

[0019] Where s′ k (t) represents the noise-like Chirp signal, s k (t) represents the frequency modulation rate. The starting frequency is b k The reference Chirp signal, Represents the noise-like phase scale factor that adjusts the randomization degree of the noise-like Chirp signal. represents the noise-like phase sequence, t represents time, T s represents the signal period of the satellite navigation signal, B s Indicates the signal bandwidth of the satellite navigation signal.

[0020] Preferably, the noise-like phase scale factor for adjusting the randomization degree of the noise-like Chirp signal is determined according to the Doppler tolerance required by the system and the decoding threshold of the physical layer security coding.

[0021] Preferably, the instantaneous coherent integration of the receiver tracking loop is obtained by the following formula:

[0022]

[0023] In the formula, S O (t) represents the peak value of the instantaneous coherent integration, B s represents the signal bandwidth of the satellite navigation signal, t represents the time, represents a noise-like phase sequence, represents the interference term of the instantaneous coherent integration, represents the carrier phase information including integer ambiguity, α represents the carrier acceleration, and μ represents the modulation frequency.

[0024] Preferably, the sample signals of the two matched filters with different modulation rates are complex Chirp signals with modulation rates that are opposite to each other.

[0025] Preferably, the impulse responses of the two matched filters with different modulation rates are respectively expressed as follows:

[0026]

[0027] In the formula, h u (t) represents the frequency modulation rate. The impulse response of the matched filter, h d (t) represents the frequency modulation rate. Impulse response of the matched filter, t represents time.

[0028] Preferably, channel coding the satellite navigation message data to obtain coded navigation message data includes: channel coding the satellite navigation message data using a channel coding method with physical layer security characteristics to obtain coded navigation message data, wherein the channel coding method is LDPC-based, Polar-based or BCH-based physical layer coding.

[0029] Preferably, modulating the coded navigation message data onto a noise-like Chirp signal to obtain a satellite navigation signal includes: modulating the coded navigation message data onto a noise-like Chirp signal using phase modulation or offset keying modulation to obtain a satellite navigation signal.

[0030] According to another aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the above methods when executing the computer program.

[0031] The technical solution of the present invention is applied to obtain satellite navigation signals through noise-like Chirp signals, and two matching filters with different modulation frequencies are used to search the satellite navigation signals in the time domain to obtain delay frequency deviation estimates; and based on the delay frequency deviation estimates, the receiver tracking loop is assisted to lock, and an instant coherent integral is obtained; then the interference term of the instant coherent integral is roughly compensated to obtain the instant coherent integral after rough compensation; and the instant coherent integral after rough compensation is processed by the Doppler frequency integration method to eliminate the integer ambiguity of the carrier phase and obtain the carrier phase estimate. The noise-like Chirp signal of the present invention has both large Doppler tolerance, multiple access characteristics and physical layer security, and can fundamentally reduce the receiver capture process to a one-dimensional search in the time domain, shorten the capture time, and at the same time improve the dynamic stress of the receiver to meet the carrier phase estimation requirements under high dynamic conditions. The application fields of the present invention include but are not limited to satellite navigation systems, pseudo-satellite positioning auxiliary systems, indoor positioning systems, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The included drawings are used to provide a further understanding of the embodiments of the present invention, which constitute a part of the specification, are used to illustrate the embodiments of the present invention, and together with the text description, explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 A flow chart of a noise-chirp-like carrier phase estimation method provided according to an embodiment of the present invention is shown;

[0034] Figure 2 A block diagram of a noise-chirp-like carrier phase estimation method provided according to an embodiment of the present invention is shown;

[0035] Figure 3a The fuzzy function of a noise-like Chirp signal provided according to an embodiment of the present invention is shown;

[0036] Figure 3b The ambiguity function of a traditional pseudo code sequence provided according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0037] It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0039] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0040] like Figure 1 As shown, the present invention provides a noise Chirp-like carrier phase estimation method, the method comprising:

[0041] S10, the transmitting end obtains a satellite navigation signal based on noise-like Chirp signal coding modulation;

[0042] S20, the receiver uses two matched filters with different modulation frequencies to perform time domain searches on the satellite navigation signals respectively to obtain delay frequency offset estimation values;

[0043] S30, assisting the delay locking tracking loop of the receiver to lock based on the delay frequency offset estimation value, and obtaining the instant coherent integration of the receiver tracking loop;

[0044] S40, using the motion information of the carrier to roughly compensate the interference term of the instantaneous coherent integration, to obtain the instantaneous coherent integration after rough compensation;

[0045] S50, using the Doppler frequency integration method to process the instantaneous coherent integration after the coarse compensation to eliminate the integer ambiguity of the carrier phase and obtain a carrier phase estimation value.

[0046] The present invention obtains satellite navigation signals through noise-like Chirp signals, uses two matching filters with different modulation frequencies to respectively search the satellite navigation signals in the time domain, and obtains the delay frequency deviation estimation value; and assists the receiver tracking loop to lock based on the delay frequency deviation estimation value, and obtains the instant coherent integral; then the interference term of the instant coherent integral is roughly compensated to obtain the instant coherent integral after rough compensation; and then the instant coherent integral after rough compensation is processed by the Doppler frequency integration method to eliminate the integer ambiguity of the carrier phase, and obtain the carrier phase estimation value. The noise-like Chirp signal of the present invention has both large Doppler tolerance, multiple access characteristics and physical layer security, and can fundamentally reduce the receiver capture process into a one-dimensional search in the time domain, shorten the capture time, and at the same time improve the dynamic stress of the receiver, and meet the carrier phase estimation requirements under high dynamic conditions. The application fields of the present invention include but are not limited to satellite navigation systems, pseudo-satellite positioning auxiliary systems, indoor positioning systems, etc.

[0047] According to an embodiment of the present invention, in S10 of the present invention, the transmitting end obtains a satellite navigation signal based on noise-like Chirp signal coding modulation, including:

[0048] S11, using two Chirp signals with the same symbol duration, the same spectrum width but completely opposite modulation rates to obtain a reference Chirp signal, wherein each Chirp signal is formed by the splicing of two Chirp signals with the same modulation rate but different starting frequencies;

[0049] S12, performing noise-like phase modulation on the reference Chirp signal according to the noise-like phase sequence to obtain a noise-like Chirp signal;

[0050] S13, performing channel coding on the satellite navigation message data to obtain coded navigation message data;

[0051] S14. Modulate the coded navigation message data onto a noise-like Chirp signal to obtain a satellite navigation signal.

[0052] Through the above settings, the multiple access performance of satellite navigation signals can be met and the security of navigation signals can be improved.

[0053] According to an embodiment of the present invention, in S12 of the present invention, a noise-like Chirp signal is obtained by the following formula:

[0054]

[0055] in,

[0056] Where s′ k (t) represents the noise-like Chirp signal, s k (t) represents the frequency modulation rate. The starting frequency is b k The reference Chirp signal, Represents the noise-like phase scale factor that adjusts the randomization degree of the noise-like Chirp signal. represents the noise-like phase sequence, t represents time, T s represents the signal period of the satellite navigation signal, B s Indicates the signal bandwidth of the satellite navigation signal.

[0057] Specifically, the noise-like phase scale factor for adjusting the randomization degree of the noise-like Chirp signal is determined according to the Doppler tolerance required by the system and the decoding threshold of the physical layer security coding. When the Doppler tolerance requirement is large, a small noise-like phase scale factor is selected, otherwise, a large noise-like phase scale factor is selected to enhance the physical layer security.

[0058] In this embodiment, the noise-like degree of the noise-like Chirp signal is adjusted by adjusting the noise-like phase scale factor. The larger the noise-like phase scale factor, the better the noise-like characteristics and multiple access characteristics of the noise-like Chirp signal, but the corresponding Doppler tolerance will also be reduced. Different satellites use unrelated noise-like phase sequences, and use the good autocorrelation characteristics of the noise-like phase to further reduce multiple access interference.

[0059] According to an embodiment of the present invention, in S13 of the present invention, channel coding is performed on satellite navigation message data to obtain coded navigation message data, including: channel coding is performed on satellite navigation message data using a channel coding method with physical layer security characteristics to obtain coded navigation message data, wherein the channel coding method is LDPC-based, Polar-based or BCH-based physical layer coding.

[0060] In this embodiment, the channel coding mode is determined according to the coding efficiency, coding gain, and decoding threshold of the physical layer security coding required by the system.

[0061] According to one embodiment of the present invention, in S14 of the present invention, modulating the coded navigation message data onto a noise-like Chirp signal to obtain a satellite navigation signal includes: modulating the coded navigation message data onto a noise-like Chirp signal using phase modulation or offset keying modulation to obtain a satellite navigation signal.

[0062] In this embodiment, a noise-like Chirp signal is applied to a satellite navigation system, and two matched filter outputs with different modulation frequencies are used to achieve stable and accurate carrier phase estimation, thereby solving the problem that a traditional direct-spread signal system satellite navigation receiver cannot estimate the accurate carrier phase in a high dynamic environment.

[0063] According to an embodiment of the present invention, in S20 of the present invention, the sample signals of the two matched filters with different modulation rates are complex Chirp signals with modulation rates that are opposite to each other.

[0064] Specifically, the impulse responses of the two matched filters with different modulation rates are expressed as follows:

[0065]

[0066] In the formula, h u (t) represents the frequency modulation rate. The impulse response of the matched filter, h d (t) represents the frequency modulation rate. Impulse response of the matched filter, t represents time.

[0067] According to an embodiment of the present invention, in S30 of the present invention, the instantaneous coherent integration of the receiver tracking loop is obtained by the following formula:

[0068]

[0069] In the formula, S o (t) represents the peak value of the instantaneous coherent integration, B s represents the signal bandwidth of the satellite navigation signal, t represents the time, represents a noise-like phase sequence, represents the interference term of the instantaneous coherent integration, represents the carrier phase information including integer ambiguity, α represents the carrier acceleration, and μ represents the modulation frequency.

[0070] The technical solution of the present invention is described in detail below in conjunction with specific embodiments. Assuming that there are K satellites in total, the satellite navigation signal of the kth satellite is acquired based on the noise-like Chirp signal, where k=1, 2, ..., K.

[0071] like Figure 2 As shown, the specific steps of the carrier phase estimation method of the noise-like Chirp are as follows:

[0072] Step 1: Time Domain Stitching

[0073] The reference Chirp signal is obtained by splicing two Chirp signals with the same symbol duration, the same spectrum width but completely opposite modulation rates, wherein each Chirp signal is spliced ​​by two Chirp signals with the same modulation rate but different starting frequencies.

[0074] Step 2: Noise-like phase modulation

[0075] The reference Chirp signal of the kth satellite is subjected to noise-like phase modulation using a noise-like phase sequence that obeys a uniform distribution in the range of [0, 2π] to obtain a noise-like Chirp signal, as shown in the following formula:

[0076]

[0077] in,

[0078] Where s′ k (t) represents the noise-like Chirp signal, s k (t) represents the frequency modulation rate. The starting frequency is b k The reference Chirp signal, Represents the noise-like phase scale factor that adjusts the randomization degree of the noise-like Chirp signal. represents the noise-like phase sequence, t represents time, T s represents the signal period of the satellite navigation signal, B s Indicates the signal bandwidth of the satellite navigation signal.

[0079] Step 3: Channel Coding

[0080] According to system requirements, select LDPC-based, Polar-based or BCH-based physical layer coding to channel code the satellite navigation message data to obtain coded navigation message data.

[0081] Step 4: Digital Modulation

[0082] According to system requirements, phase modulation, offset keying modulation or other signal modulation methods are selected to modulate the coded navigation message data onto a noise-like Chirp signal to obtain a satellite navigation signal.

[0083] Step 5: Capture and trace

[0084] At the receiving end, two matched filters with different modulation rates are used to search the navigation signal in the time domain. The signal is captured by detecting the peak of the matched filter. The linear coupling of the delay frequency offset is solved according to the positional relationship of the output peaks of the two matched filters to obtain the delay frequency offset estimation value. The sample signals used by the two matched filters are complex Chirp signals with opposite modulation rates. The impulse responses of the two matched filters can be expressed as follows:

[0085]

[0086] In the formula, h u (t) represents the frequency modulation rate. The impulse response of the matched filter, h d(t) represents the frequency modulation rate. Impulse response of the matched filter, t represents time.

[0087] Then, the captured delay frequency deviation estimation value is used to assist the receiver tracking loop to quickly lock. The tracking loop adopts a delay locking tracking loop. The local generates three sample signals, namely delayed, immediate, and advanced, and performs coherent integration with the tracking loop receiving signal, thereby obtaining three-way coherent integration results. The three-way integration results are used to adjust the phase characteristics of the noise-like Chirp signal. Since the navigation signal has a large Doppler tolerance and linear coupling characteristics of delay frequency deviation, the noise-like Chirp delay locking loop can still output a peak value even when "lost lock" occurs. The peak information is shown in the following formula:

[0088]

[0089] In the formula, S o (t) represents the peak value of the instantaneous coherent integration, B s represents the signal bandwidth of the satellite navigation signal, t represents the time, represents a noise-like phase sequence, represents the interference term of the instantaneous coherent integration, represents the carrier phase information including integer ambiguity, α represents the carrier acceleration, and μ represents the modulation frequency.

[0090] Step 6: Coarse Interference Compensation

[0091] The motion information of the carrier is used to roughly compensate the interference items of the instant coherent integration to eliminate the interference items. Get the instant coherent integration after coarse compensation.

[0092] Step 7: Doppler frequency integration

[0093] The Doppler frequency integration method is used to process the instantaneous coherent integration after coarse compensation to eliminate the integer ambiguity of the carrier phase and obtain the carrier phase estimation value.

[0094] Figure 3a FIG. 4 shows a fuzzy function of a noise-like Chirp signal provided according to an embodiment of the present invention, wherein: Figure 3a is k = 0.5, the fuzzy function of the noise-like Chirp signal; Figure 3b FIG. 4 shows an ambiguity function of a conventional pseudo code sequence according to an embodiment of the present invention. Figure 3a and 3bIt can be seen that the ambiguity function of the noise-like Chirp signal is ridge-shaped, while that of the traditional pseudo-code sequence is pin-shaped, which means that when the noise-like Chirp signal has a large frequency deviation, the matched filter can still output a peak value, so it has a Doppler tolerance much larger than that of the pseudo-code sequence.

[0095] According to another aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the above methods when executing the computer program.

[0096] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0097] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0098] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A noise-like chirp carrier phase estimation method, characterized in that: The method comprises: The transmitting end obtains the satellite navigation signal based on the noise-like Chirp signal coding modulation; The receiver uses two matched filters with different modulation frequencies to search the satellite navigation signal in the time domain to obtain the estimated value of the delay and frequency offset; Based on the estimated value of the time delay and frequency offset, the delay locking tracking loop of the receiver is assisted to lock, and the instant coherent integration of the receiver tracking loop is obtained; The interference term of the instantaneous coherent integration is roughly compensated by using the motion information of the carrier, so as to obtain the instantaneous coherent integration after the rough compensation; The Doppler frequency integration method is used to process the instantaneous coherent integration after coarse compensation to eliminate the integer ambiguity of the carrier phase and obtain the carrier phase estimation value.

2. The method according to claim 1, characterized in that: The transmitting end obtains the satellite navigation signal based on the noise-like Chirp signal coding modulation, including: A reference Chirp signal is obtained by splicing two Chirp signals with the same symbol duration, the same spectrum width but completely opposite modulation rates, wherein each Chirp signal is spliced ​​by two Chirp signals with the same modulation rate but different starting frequencies; Performing noise-like phase modulation on the reference Chirp signal according to the noise-like phase sequence to obtain a noise-like Chirp signal; Channel coding the satellite navigation message data to obtain coded navigation message data; The coded navigation message data is modulated onto a noise-like Chirp signal to obtain a satellite navigation signal.

3. The method according to claim 1 or 2, characterized in that: The noise-like Chirp signal is obtained by the following formula: in, Where s′ k (t) represents the noise-like Chirp signal, s k (t) represents the frequency modulation rate. The starting frequency is b k The reference Chirp signal, Represents the noise-like phase scale factor that adjusts the randomization degree of the noise-like Chirp signal. represents the noise-like phase sequence, t represents time, T s represents the signal period of the satellite navigation signal, B s Indicates the signal bandwidth of the satellite navigation signal.

4. The method according to claim 3, characterized in that The noise-like phase scale factor for adjusting the randomization degree of the noise-like Chirp signal is determined according to the Doppler tolerance required by the system and the decoding threshold of the physical layer security coding.

5. The method according to claim 1 or 2, characterized in that: The instantaneous coherent integration of the receiver tracking loop is obtained by: In the formula, S O (t) represents the peak value of the instantaneous coherent integration, B s represents the signal bandwidth of the satellite navigation signal, t represents the time, represents a noise-like phase sequence, represents the interference term of the instantaneous coherent integration, represents the carrier phase information including integer ambiguity, α represents the carrier acceleration, and μ represents the modulation frequency.

6. The method according to claim 1 or 2, characterized in that: The sample signals of the two matched filters with different modulation frequencies are complex Chirp signals with modulation frequencies that are opposite to each other.

7. The method according to claim 6, characterized in that The impulse responses of two matched filters with different modulation rates are expressed as follows: In the formula, h u (t) represents the frequency modulation rate. The impulse response of the matched filter, h d (t) represents the frequency modulation rate. Impulse response of the matched filter, t represents time.

8. The method according to claim 1 or 2, characterized in that: Channel coding the satellite navigation message data to obtain the coded navigation message data includes: channel coding the satellite navigation message data using a channel coding method with physical layer security characteristics to obtain the coded navigation message data, wherein the channel coding method is LDPC-based, Polar-based or BCH-based physical layer coding.

9. The method according to claim 1 or 2, characterized in that: Modulating the coded navigation message data onto a noise-like Chirp signal to obtain a satellite navigation signal includes: modulating the coded navigation message data onto a noise-like Chirp signal using phase modulation or offset keying modulation to obtain a satellite navigation signal.

10. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 9 is implemented.

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