Signal tracking method and signal tracking device

Abstract

The present application discloses a signal tracking method and a signal tracking device. The method includes: receiving a broadband composite signal; the broadband composite signal includes at least one upper sideband signal component and at least one lower sideband signal component; using a first local instant code to track a first target signal to at least determine the current fusion phase and current fusion frequency of the carrier and subcarrier; using a local instant carrier to track a second target signal to at least determine the current code phase, current code frequency, current subcarrier phase and current subcarrier frequency; one of the first target signal and the second target signal is an upper sideband signal component, and the other is a lower sideband signal component; the first local instant code is determined based on the previous code phase and the previous code frequency, and the local instant carrier is determined based on the previous fusion phase and the previous fusion frequency. The present application solves the problem of coupling between carrier phase and subcarrier phase, and has a higher accuracy rate.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of satellite navigation tracking technology, and in particular to a signal tracking method and a signal tracking device. Background Art

[0002] As demand for positioning accuracy continues to grow, the Global Navigation Satellite System (GNSS) continues to evolve. Compared to binary phase-shift keying (BPSK) signals, subcarrier-modulated signals offer frequency-domain separation, wider root-mean-square (RMS) bandwidth, and higher ranging accuracy. Therefore, current GNSS signals typically utilize subcarrier-modulated signals, such as AltBOC or ACE-BOC wideband composite signals.

[0003] Both the AltBOC signal and the ACE-BOC wideband composite signal are dual-frequency, constant-envelope composite signals. In most cases, both have four signal components: two in the lower sideband and two in the upper sideband. While the power of the four components of the AltBOC signal is equal, the power of the four components of the ACE-BOC wideband composite signal can be adjusted, meaning that the power of the four components can be unequal. Compared to the AltBOC signal, the ACE-BOC wideband composite signal offers greater flexibility in signal component power allocation, meeting diverse GNSS design and application requirements.

[0004] Although an ACE-BOC wideband composite signal generally has four signal components, in special cases, such as when the power of a signal component may be modulated to zero to meet specific application requirements, the number of signal components of the ACE-BOC wideband composite signal is less than four. However, regardless of whether the ACE-BOC wideband composite signal has four signal components, the carrier phase and subcarrier phase of each signal component are severely coupled.

[0005] The tracking technology used for GNSS signals is generally DBT technology or ASYM-DBT technology. Among them, DBT technology is only applicable to GNSS signals with equal signal component power, such as AltBOC signals, and cannot solve the problem of carrier phase and subcarrier phase coupling. Although ASYM-DBT technology can be applied to GNSS signals with unequal signal component power, ASYM-DBT technology targets the amplitude domain of the signal components. In other words, ASYM-DBT technology achieves signal tracking by estimating and normalizing the power, or amplitude, of each signal component. In other words, ASYM-DBT technology first converts unequal power signal components into equal power signal components before using DBT technology. However, the estimation of signal component power will be affected by many factors and has very low accuracy, which will result in unequal signal power after normalization, making the subsequent DBT technology unusable. From the above, it can be seen that the existing tracking technology cannot solve the problem of carrier phase and subcarrier phase coupling and is not applicable to ACE-BOC broadband composite signals. Summary of the Invention

[0006] The signal tracking method provided according to the first aspect of the present application includes:

[0007] Receive a broadband composite signal; wherein the broadband composite signal includes at least one upper sideband signal component and at least one lower sideband signal component;

[0008] Tracking the first target signal using the first local instant code to determine at least a current fusion phase and a current fusion frequency of the carrier and the subcarrier; and

[0009] Tracking the second target signal using the local instantaneous carrier to determine at least a current code phase, a current code frequency, a current subcarrier phase, and a current subcarrier frequency;

[0010] Among them, one of the first target signal and the second target signal is the upper sideband signal component, and the other is the lower sideband signal component; the first local instant code is determined based on the previous code phase and the previous code frequency, and the local instant carrier is determined based on the previous fusion phase and the previous fusion frequency.

[0011] The signal tracking device provided according to the second aspect of the present application includes:

[0012] A receiving module receives a broadband composite signal; wherein the broadband composite signal includes at least one upper sideband signal component and at least one lower sideband signal component

[0013] The carrier loop tracks the first target signal using the first local instant code to determine at least a current fusion phase and a current fusion frequency of the carrier and the subcarrier; and

[0014] The code loop and the subcarrier loop track the second target signal using the local instantaneous carrier to determine at least a current code phase, a current code frequency, a current subcarrier phase, and a current subcarrier frequency;

[0015] Among them, one of the first target signal and the second target signal is the upper sideband signal component, and the other is the lower sideband signal component; the first local instant code is determined based on the previous code phase and the previous code frequency, and the local instant carrier is determined based on the previous fusion phase and the previous fusion frequency.

[0016] The signal tracking method and signal tracking device provided in the embodiments of the present application respectively track two different signal components, namely the upper sideband signal component and the lower sideband signal component, and share the fusion phase and fusion frequency of the carrier and subcarrier determined by tracking one of the signal components with the other signal component. Therefore, when tracking the signal component with the shared fusion phase and fusion frequency, it is only necessary to determine the code phase, code frequency, subcarrier phase and subcarrier frequency, thereby solving the problem of carrier phase and subcarrier phase coupling. It can be seen that the present application utilizes a phase cross-assisted method to jointly process and track the upper sideband signal component and the lower sideband signal component, which not only solves the problem of carrier phase and subcarrier phase coupling, but is also applicable to ACE-BOC broadband composite signals. Moreover, the present application targets the phase domain of the signal component and does not estimate the power of the signal component, while the ASYM-DBT technology targets the amplitude domain of the signal component, that is, estimates the power of the signal component. Compared with power estimation, the accuracy of phase tracking is higher.

[0017] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present application, nor is it intended to limit the scope of the present application. Other features of the present application will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Other features, objects, and advantages of the present application will become more apparent by reading the detailed description of the non-limiting embodiments made with reference to the following drawings. The drawings are provided for a better understanding of the present invention and do not constitute a limitation of the present application. In the drawings:

[0019] Figure 1 is a flow chart of a signal tracking method according to the present application;

[0020] Figure 2is a schematic diagram of receiving a broadband composite signal according to one of the signal tracking methods of the present application;

[0021] Figure 3 is a schematic diagram of another method for receiving a broadband composite signal according to the signal tracking method of the present application;

[0022] Figure 4 is a partial schematic diagram of one of the signal tracking devices according to the present application;

[0023] Figure 5 is a partial schematic diagram of another signal tracking device according to the present application;

[0024] Figure 6 Schematic diagram of the change in the carrier-to-noise ratio of an ACE-BOC signal over time using the signal tracking method of the present application and using the existing BPSK-Like technology;

[0025] Figure 7 It is a graph of the autocorrelation function of two lower sideband signal components in the process of tracking the ACE-BOC signal using the signal tracking method of the present application;

[0026] Figure 8 Schematic diagram of tracking error changes when using the signal tracking method of the present application and the existing BPSK-Like technology to track ACE-BOC signals under different loop filtering conditions;

[0027] Figure 9 1 is a schematic diagram showing the time variation of the code-subtracted carrier of an ACE-BOC signal using the signal tracking method of the present application and the existing BPSK-Like technology.

[0028] Reference numerals:

[0029] 100, the power main lobe of the upper sideband signal component;

[0030] 200, the power main lobe of the lower sideband signal component; 300, single signal channel;

[0031] 310, first signal channel; 320, second signal channel;

[0032] 400, carrier digitally controlled oscillator; 410, first correlator;

[0033] 421, first product correlator; 422, first integrating correlator; 430, first phase detector;

[0034] 500, subcarrier digitally controlled oscillator; 510, third correlator;

[0035] 521, second product correlator; 522, third product correlator;

[0036] 530, second integral correlator; 540, second phase detector;

[0037] 600, code digital controlled oscillator; 610, third phase detector. DETAILED DESCRIPTION

[0038] In the description of the embodiments of the present application, the terms "first", "second" and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0039] The following description of exemplary embodiments of the present application is made in conjunction with the accompanying drawings, including various details of the embodiments of the present application to facilitate understanding. These details should be considered as merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present application. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0040] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0041] In related technologies, GNSS signals typically utilize subcarrier-modulated signals, such as the ACE-BOC wideband composite signal. Typically, the ACE-BOC wideband composite signal has four signal components, two of which are upper sideband components and two of which are lower sideband components. The power allocation of these four signal components in the ACE-BOC wideband composite signal offers greater flexibility, meeting diverse GNSS design and application requirements.

[0042] The ACE-BOC broadband composite signal can be expressed as s(t):

[0043]

[0044] Among them, P LI and P LQ are the power of the two lower sideband signal components, P UI and P UQ are the powers of the two upper sideband signal components respectively; s LI (t) and s LQ (t) are the baseband spread spectrum signals of the two lower sideband signal components, s UI (t) and s UQ (t) are baseband spread spectrum signals of the two upper sideband signal components; sc L (t) is the subcarrier signal of the lower sideband signal component, sc U (t) is the subcarrier signal of the upper sideband signal component; Ts =1 / f s , f s is the subcarrier frequency; I IM (t) is the intermodulation term, and f0 is the carrier frequency.

[0045] The baseband spread spectrum signal in formula (1.1) is used to maintain the constant envelope property of the corresponding signal component. The baseband spread spectrum signal of the upper sideband signal component or the lower sideband signal component can be expressed as:

[0046]

[0047] Among them, l∈{L,U}, X∈{I,Q}; s LI (t) and s LQ (t) are the baseband spread spectrum signals of the two lower sideband signal components, s UI (t) and s UQ (t) are baseband spread spectrum signals of the two upper sideband signal components; d LI (t) and d LQ (t) are the navigation message bits carried by the two lower sideband signal components, d UI (t) and d UQ (t) are the navigation message bits carried by the two upper sideband signal components; c LI (t) and c LQ (t) are the spread spectrum code signals of the two lower sideband signal components, c UI (t) and c UQ (t) are the spread spectrum code signals of the two upper sideband signal components respectively; and are the spreading code sequences used by the two lower sideband signal components respectively, and are the spreading code sequences used by the two upper sideband signal components respectively; and are the code rates of the two lower sideband signal components, and are the code rates of the two upper sideband signal components respectively; p(t) represents a rectangular pulse. The value of t in the interval is 1, and the value of t in the other intervals is 0.

[0048] Given that the power main lobe of the ACE-BOC wideband composite signal is very wide, and the bandwidth of the RF front-end of the receiving module in the related art is equal to or slightly larger than the power main lobe of the ACE-BOC wideband composite signal, that is, the bandwidth of the RF front-end of the receiving module can only include the power main lobe of the ACE-BOC wideband composite signal, the subcarrier signal of the ACE-BOC wideband composite signal can be simplified to a sinusoidal signal. The simplified ACE-BOC wideband composite signal can be expressed as r(t):

[0049]

[0050] Among them, P LI and P LQ are the power of the two lower sideband signal components, P UI and P UQ are the powers of the two upper sideband signal components respectively; s LI (t) and s LQ (t) are the baseband spread spectrum signals of the two lower sideband signal components, s UI (t) and s UQ (t) are the baseband spread spectrum signals of the two upper sideband signal components; τ is the propagation delay of the signal; f s is the subcarrier frequency; f d is the Doppler shift; is the initial carrier phase.

[0051] The above formula (1.3) can be expressed as follows after sorting:

[0052] r(t)=r LI (t)-r LQ (t)+r UI (t)-r UQ (t); (1.4)

[0053] in,

[0054]

[0055]

[0056]

[0057]

[0058] θ=2πf s τ;

[0059] Among them, r LI (t) and r LQ (t) are the two lower sideband signal components, r UI(t) and r UQ (t) are two upper sideband signal components respectively; P LI and P LQ are the power of the two lower sideband signal components, P UI and P UQ are the powers of the two upper sideband signal components respectively; s LI (t) and s LQ (t) are the baseband spread spectrum signals of the two lower sideband signal components, s UI (t) and s UQ (t) are the baseband spread spectrum signals of the two upper sideband signal components; τ is the signal propagation delay; f0 is the carrier frequency; f d is the Doppler frequency shift; f s is the subcarrier frequency; φ is the carrier phase, and θ is the subcarrier phase.

[0060] Therefore, according to formula (1.4), the carrier phase and subcarrier phase of each signal component of the ACE-BOC wideband composite signal, namely the upper sideband signal component or the lower sideband signal component, are contained in the same sine function or cosine function. In other words, the carrier phase and subcarrier phase of each signal component are severely coupled. However, existing tracking technologies such as DBT technology or ASYM-DBT technology cannot solve the problem of carrier phase and subcarrier phase coupling and are not suitable for ACE-BOC wideband composite signals.

[0061] In addition, according to the above formula (1.4), the lower sideband signal component, namely r LI (t) or r LQ (t) signal propagation delay τ, carrier frequency f0, Doppler shift f d and carrier phase φ are respectively related to the upper sideband signal component r UI (t) or r UQ (t) signal propagation delay τ, carrier frequency f0, Doppler shift f d The same value as the carrier phase φ, and the lower sideband signal component is r LI (t) or r LQ (t) the subcarrier frequency f s and subcarrier phase θ are respectively related to the upper sideband signal component r UI (t) or r UQ (t) the subcarrier frequency f s The subcarrier phase θ has the opposite value. It can be seen that the carrier phase φ and subcarrier phase θ of the lower sideband signal component are highly correlated with the carrier phase φ and subcarrier phase θ of the upper sideband signal component.

[0062] Based on this, in order to solve the above problems, Figure 1As shown, an embodiment of the present application provides a signal tracking method, the method comprising:

[0063] S100, receiving a broadband composite signal; wherein the broadband composite signal includes at least one upper sideband signal component and at least one lower sideband signal component;

[0064] S200: Tracking a first target signal using a first local instant code to at least determine a current fusion phase and a current fusion frequency of a carrier and a subcarrier;

[0065] S300, tracking the second target signal using the local instantaneous carrier to determine at least a current code phase, a current code frequency, a current subcarrier phase, and a current subcarrier frequency;

[0066] Among them, one of the first target signal and the second target signal is an upper sideband signal component, and the other is a lower sideband signal component; the first local instant code is determined based on a previous code phase and a previous code frequency, and the local instant carrier is determined based on a previous fusion phase and a previous fusion frequency.

[0067] The present application tracks two different signal components, namely the upper sideband signal component and the lower sideband signal component, respectively, and shares the fusion phase and fusion frequency of the carrier and subcarrier determined by tracking one of the signal components with the other signal component. Therefore, when tracking the signal component with the shared fusion phase and fusion frequency, it is only necessary to determine the code phase, code frequency, subcarrier phase and subcarrier frequency, thereby solving the problem of carrier phase and subcarrier phase coupling. It can be seen that the present application uses a phase cross-assisted method to jointly process and track the upper sideband signal component and the lower sideband signal component, which not only solves the problem of carrier phase and subcarrier phase coupling, but also can be applied to ACE-BOC broadband composite signals. Moreover, the present application targets the phase domain of the signal component and does not estimate the power of the signal component, while the ASYM-DBT technology targets the amplitude domain of the signal component, that is, estimates the power of the signal component. Compared with power estimation, the accuracy of phase tracking is higher.

[0068] The following is a detailed introduction to the various steps of the signal tracking method in the embodiment of the present application.

[0069] Step S100

[0070] Wideband composite signals can be received in a variety of ways, such as:

[0071] Method 1: Single-channel broadband receiving method, such as Figure 2 As shown, step S100 includes:

[0072] S110. Use a single signal channel 300 to simultaneously receive the upper sideband signal component and the lower sideband signal component; specifically, place the center frequency of the RF front end of the receiving module at the center frequency between the upper sideband signal component and the lower sideband signal component, and the filter of the receiving module is a low-pass filter. The bandwidth of the low-pass filter, that is, the receiving bandwidth of the single signal channel 300, covers the power main lobe 100 of the upper sideband signal component and the power main lobe 200 of the lower sideband signal component.

[0073] Method 2: Dual-channel narrowband receiving method, such as Figure 3 As shown, step S100 includes:

[0074] S110, using the first signal channel 310 to receive an upper sideband signal component;

[0075] S120, using a second signal channel 320 that is independent of and parallel to the first signal channel 310 to receive a lower sideband signal component;

[0076] Specifically, if Figure 3 As shown, the center frequency of the RF front end of the receiving module is placed at the center frequency between the upper sideband signal component and the lower sideband signal component. The first filter of the receiving module is a bandpass filter. The bandwidth of the first filter, that is, the receiving bandwidth of the first signal channel 310, covers the power main lobe 100 of the upper sideband signal component. The second filter of the receiving module is also a bandpass filter. The bandwidth of the second filter, that is, the receiving bandwidth of the second signal channel 320, covers the power main lobe 200 of the lower sideband signal component.

[0077] As can be seen from the above, the receiving bandwidth of the single signal channel 300 in Method 1 is very wide, while the receiving bandwidth of the first signal channel 310 and the receiving bandwidth of the second signal channel 320 in Method 2 are both relatively narrow. If the filtering resources of the RF front-end of the receiving module are sufficient, Method 1 or Method 2 can be used to receive the broadband composite signal. However, if the filtering resources of the RF front-end of the receiving module are insufficient, for example, if the receiving bandwidth of the single signal channel 300 cannot cover the power main lobe 100 of the upper sideband signal component and the power main lobe 200 of the lower sideband signal component, only Method 2 can be used to receive the broadband composite signal.

[0078] In addition, it should be noted that since method one only uses one signal channel, the upper sideband signal component and the lower sideband signal component are received synchronously, and the phases of the two are naturally kept consistent, while method two uses the first signal channel 310 and the second signal channel 320 to receive the upper sideband signal component and the lower sideband signal component respectively. Therefore, compared with method one, in order to ensure that the phase of the upper sideband signal component and the phase of the lower sideband signal component in method two remain consistent, step S110 and step S120 in method two need to be performed synchronously, that is, the moment when the first signal channel 310 receives the upper sideband signal component is the same as the moment when the second signal channel 320 receives the lower sideband signal component.

[0079] The following still takes the ACE-BOC broadband composite signal as an example. The ACE-BOC broadband composite signal includes two upper sideband signal components, namely r UI (t) and r UQ (t) and the two lower sideband signal components r LI (t) and r LQ (t).

[0080] Taking the first mode as an example, the upper sideband signal component and the lower sideband signal component synchronously received by the receiving module are r UI (t) and r LI (t), that is, the signal to be tracked r I (t) is r UI (t)+r LI (t). According to formula (1.4) above, If the above sideband signal component r UI The phase of (t) is taken as the reference phase, then the upper sideband signal component r UI (t) can be expressed as Among them, φ UI (t)=2πf UI +γ,f UI =f0+f d +f s ,γ=φ-θ. Based on this, the lower sideband signal component r LI (t) can be expressed as Among them, θ L (t)=-2πf s,L t+μ,f s,L =2f s , μ=2θ. It can be seen that θ L (t) is only related to the subcarrier and has nothing to do with the carrier, tracking θ L (t) is not affected by the carrier phase.

[0081] Of course, the upper sideband signal component and the lower sideband signal component received synchronously by the receiving module are r UI (t) and r LI (t) can also be the lower sideband signal component r LI The phase of (t) is used as the reference phase, that is, the lower sideband signal component r LI (t) can be expressed as Among them, φ LI (t)=2π(f0+f d -f s )t+φ+θ. Then, the upper sideband signal component r UI (t) can be expressed as

[0082] Therefore, when using method 1, there are 8 types of signals to be tracked:

[0083] The first type, the above sideband signal component r UI The phase of (t) is used as the reference phase, and the signal to be tracked r I (t) is r UI (t)+r LI (t);

[0084] The second type, the following sideband signal component r LI The phase of (t) is used as the reference phase, and the signal to be tracked r I (t) is r UI (t)+r LI (t);

[0085] The third type, the above sideband signal component r UQ The phase of (t) is used as the reference phase, and the signal to be tracked r IQ (t) is r UQ (t)+r LI (t);

[0086] The fourth type, the following sideband signal component r LI The phase of (t) is used as the reference phase, and the signal to be tracked r IQ (t) is r UQ (t)+r LI (t);

[0087] The fifth type, the above sideband signal component r UI The phase of (t) is used as the reference phase, and the signal to be tracked r I (t) is r UI (t)+r LQ (t);

[0088] The sixth type, the following sideband signal component rLQ The phase of (t) is used as the reference phase, and the signal to be tracked r I (t) is r UI (t)+r LQ (t);

[0089] Seventh, the above sideband signal component r UQ The phase of (t) is used as the reference phase, and the signal to be tracked r I (t) is r UQ (t)+r LQ (t);

[0090] The eighth type, the following sideband signal component r LQ The phase of (t) is used as the reference phase, and the signal to be tracked r I (t) is r UQ (t)+r LQ (t).

[0091] Similarly, in the case of the second method, there are also 8 types of signals to be tracked. For the first and second methods, there are a total of 16 types of signals to be tracked. It can be seen that compared with the existing technology, the present application is more flexible and can meet different application requirements.

[0092] Step S200

[0093] In order to determine the current fusion phase of the carrier and the subcarrier, step S200 includes:

[0094] S210, performing carrier stripping on the broadband composite signal based on a previous fusion phase and a previous fusion frequency to obtain a baseband signal of a first target signal;

[0095] S220, determining a target correlation value corresponding to the first target signal according to the baseband signal of the first target signal and the first local instant code;

[0096] S230, performing phase discrimination according to the target correlation value to determine the fusion phase error and the current fusion frequency;

[0097] S240: Update the previous fusion phase according to the fusion phase error to obtain the current fusion phase.

[0098] Combine Figure 4 and Figure 5 As shown, the following takes the first type of signal to be tracked mentioned above as an example, that is, the signal to be tracked r I (t) is r UI (t)+r LI (t), the reference phase is the upper sideband signal component r UI Phase φ of (t) UI(t) as an example, the specific steps for obtaining the current fusion phase are described as follows:

[0099] S210, based on the previous fusion phase and the previous fusion frequency f UI Carrier stripping is performed on the broadband composite signal, that is, the signal to be tracked r I (t) Carrier stripping is performed. Specifically, the carrier digital control oscillator 400 is used to carry out the carrier stripping according to the previous fusion phase. and the previous fusion frequency f UI Generate local instant carrier in, f UI =f0+f d +f s , f0 is the carrier frequency; f d is the Doppler frequency shift; f s is the subcarrier frequency. Calculate the product of the broadband composite signal and the local instantaneous carrier, that is, calculate r I (t) with The product of s is used to obtain the baseband signal s of the first target signal UI (t-τ).

[0100] S220, based on the baseband signal s of the first target signal UI (t-τ) and the first local instant code Determine a target correlation value corresponding to the first target signal. As an example, the target correlation value includes a first correlation value I UI,P and the second correlation value Q UI,P Specifically, in the first integration interval [0, T], the baseband signal s of the first target signal is UI (t-τ) and the first local instant code Integrate the product of to obtain the first correlation value I UI,P and the second correlation value Q UI,P :

[0101]

[0102] Among them, R∈{I,Q}, r I (t) is the signal to be tracked, is the local instant carrier, is the first local instant code, T is the coherent integration time, is the previous code phase;

[0103] The first correlation value I can be obtained by calculating formula (1.5) UI,P and the second correlation value Q UI,P :

[0104]

[0105]

[0106] Among them, d UI is the upper sideband signal component r UI (t) Navigation message bits carried, P UI is the upper sideband signal component r UI (t) power, is the baseband signal s UI (t), where T is the coherent integration time, is the previous code phase, sinc(Δf UI T)=sin(πΔf UI T) / (πΔf UI T), Δf UI is the upper sideband signal component r UI (t) is the fusion frequency error, Δγ is the upper sideband signal component r UI The phase error of (t).

[0107] Since Δf UI ≈0, so the above formulas (1.6) and (1.7) can be rearranged as follows:

[0108]

[0109]

[0110] S230, according to the target correlation value, that is, the first correlation value I UI,P and the second correlation value Q UI,P Perform phase discrimination to determine the fusion phase error Δγ and the current fusion frequency. Specifically, based on formula (1.8) and formula (1.9), the fusion phase error Δγ can be calculated using the following formula:

[0111]

[0112] S240, update the previous fusion phase according to the fusion phase error Δγ to get the current fusion phase.

[0113] It should be noted that when executing step S230, any phase detector in the art capable of implementing step S230 may be used to determine the fused phase error and the current fused frequency. For example, the phase detector may be, but is not limited to, a carrier tracking loop phase detector.

[0114] Step S300

[0115] In order to determine the current code phase and the current subcarrier phase, step S300 includes:

[0116] S310, performing carrier stripping on the broadband composite signal based on the local instantaneous carrier to obtain a baseband signal of the second target signal;

[0117] S320, determining an advance correlation value, an immediate correlation value, and a delayed correlation value corresponding to the second target signal according to the baseband signal of the second target signal, a previous code phase, a previous code frequency, a previous subcarrier phase, and a previous subcarrier frequency

[0118] S330, performing phase discrimination according to the advance correlation value and the delay correlation value to determine the code phase error and the current code frequency;

[0119] S340, updating the previous code phase according to the code phase error to obtain a current code phase;

[0120] S350, performing phase discrimination according to the target correlation value and the instantaneous correlation value to determine the subcarrier phase error and the current subcarrier frequency;

[0121] S360: Update the previous subcarrier phase according to the subcarrier phase error to obtain a current subcarrier phase.

[0122] The following takes the first signal to be tracked as an example to illustrate the specific steps for obtaining the current code phase and the current subcarrier phase:

[0123] S310: Receive local real-time carrier wave Based on local real-time carrier Carrier stripping is performed on the broadband composite signal. Specifically, the product of the broadband composite signal and the local instantaneous carrier is calculated, that is, r I (t) with The product of is obtained to obtain the baseband signal s of the second target signal LI (t-τ).

[0124] S320, based on the baseband signal s of the second target signal LI (t-τ), previous code phase Previous code frequency, previous subcarrier phase and the previous subcarrier frequency Determine an early correlation value, an immediate correlation value, and a delayed correlation value corresponding to the second target signal. As an example, the early correlation value includes a first early correlation value I LI,E and the second advance correlation value Q LI,E , the immediate correlation value includes a first immediate correlation value I LI,P and the second instantaneous correlation value Q LI,p , the delay-related value includes a first delay-related value ILI,L and the second delayed correlation value Q LI,L Specifically: S321, using the code digital control oscillator 600 according to the previous code phase and the previous code frequency to generate the first local instant code Local advance code Second local instant code and local delay code S322, using the subcarrier digital controlled oscillator 500 according to the previous subcarrier phase and the previous subcarrier frequency Generate local instant subcarrier sc LI (t); where S323, based on the baseband signal s of the second target signal LI (t-τ), local instantaneous subcarrier sc LI (t), local advance code Second local instant code and local delay code Determine the first advance correlation value I LI,E , the second advance correlation value Q LI,E , the first instantaneous correlation value I LI,P , the second immediate correlation value Q LI,p , first delay related value I LI,L and the second delayed correlation value Q LI,L .

[0125] S330, according to the first advance correlation value I LI,E , the second advance correlation value Q LI,E , first delay related value I LI,L and the second delayed correlation value Q LI,L Perform phase detection to determine the code phase error and the current code frequency; specifically, the code phase error can be calculated using the following formula:

[0126]

[0127] S340, according to the code phase error Update the previous code phase To obtain the current code phase;

[0128] S350, according to the first correlation value I UI,P , the second correlation value Q UI,P , the first instantaneous correlation value I LI,P , the second immediate correlation value Q LI,p Phase detection is performed to determine the subcarrier phase error Δμ and the current subcarrier frequency. Specifically, the subcarrier phase error Δμ can be calculated using the following formula:

[0129]

[0130] S360, update the previous subcarrier phase according to the subcarrier phase error Δμ To obtain the current subcarrier phase.

[0131] It should be noted that when executing step S330, any phase detector known in the art capable of implementing step S330 may be used to determine the code phase error and code frequency. For example, the phase detector may be, but is not limited to, a code tracking loop phase detector. Similarly, when executing step S350, any phase detector known in the art capable of implementing step S350 may be used to determine the subcarrier phase error and subcarrier frequency. For example, the phase detector may be, but is not limited to, a subcarrier tracking loop phase detector.

[0132] The above step S323 may include:

[0133] ① For example, using the following formula (2.1), in the second integration interval, the baseband signal s of the second target signal is LI (t-τ), local instantaneous subcarrier sc LI (t) and local advance code The product of is integrated to obtain the first advance correlation value I LI,E and the second advance correlation value Q LI,E :

[0134]

[0135] Among them, R∈{I,Q}, r I (t) is the signal to be tracked, is the local instant carrier, sc LI (t) is the local instantaneous subcarrier, is the local advance code, T is the coherent integration time, is the previous code phase, δ E The delay amount for generating the local advance code.

[0136] Thus, the first advance correlation value and the second advance correlation value can be obtained by calculating formula (2.1):

[0137]

[0138]

[0139] Among them, d LI is the lower sideband signal component r LI (t) Navigation message bits carried, P UI is the lower sideband signal component r LI (t) power, is the baseband signal s LI The autocorrelation function of (t), δ E is the delay amount for generating the local advance code, T is the coherent integration time, is the previous code phase, sinc((Δf UI -Δf s,L )T)=sin(π(Δf UL -Δf s,L )T) / (π(Δf UL -Δf s,L )T), Δf UL is the lower sideband signal component r LI (t) carrier frequency error, Δf s,L is the lower sideband signal component r LI (t) is the subcarrier frequency error, Δγ is the lower sideband signal component r LI (t), Δμ is the fusion phase error of the lower sideband signal component r LI (t) is the subcarrier phase error.

[0140] Since Δf UL ≈0,Δf s,L ≈0, so the above formulas (2.2) and (2.3) can be sorted as follows:

[0141]

[0142]

[0143] ②Use the following formula to calculate the baseband signal s of the second target signal in the second integration interval: LI (t-τ), local instantaneous subcarrier sc LI (t) and the second local instant code The product of is integrated to obtain the first instantaneous correlation value I LI,P and the second instantaneous correlation value Q LI,p .

[0144]

[0145] The calculation principle is the same as that of step ① above. The first instantaneous correlation value I can be obtained by the above formula: LI,P and the second instantaneous correlation value Q LI,p :

[0146]

[0147]

[0148] Among them, d LI is the lower sideband signal component rLI (t) Navigation message bits carried, P UI is the lower sideband signal component r LI (t) power, is the baseband signal s LI The autocorrelation function of (t), δ E is the delay for generating the second local prompt code, T is the coherent integration time, is the previous code phase, Δγ is the lower sideband signal component r LI (t), Δμ is the fusion phase error of the lower sideband signal component r LI (t) is the subcarrier phase error.

[0149] ③ Use the following formula to calculate the baseband signal s of the second target signal in the second integration interval: LI (t-τ), local instantaneous subcarrier sc LI (t) and local delay code The product of is integrated to obtain the first delay correlation value I LI,L and the second delayed correlation value Q LI,L .

[0150]

[0151] The calculation principle is the same as that of step ① above. The first instantaneous correlation value I can be obtained by the above formula: LI,L and the second instantaneous correlation value Q LI,L :

[0152]

[0153]

[0154] Among them, d LI is the lower sideband signal component r LI (t) Navigation message bits carried, P UI is the lower sideband signal component r LI (t) power, is the baseband signal s LI The autocorrelation function of (t), δ L is the delay amount for generating the local delay code, T is the coherent integration time, is the previous code phase, Δγ is the lower sideband signal component r LI (t), Δμ is the fusion phase error of the lower sideband signal component r LI (t) is the subcarrier phase error.

[0155] In addition, after executing step S300, the signal tracking method of the embodiment of the present application further includes:

[0156] S400, according to the current code phase Current subcarrier phase and the current subcarrier frequency f s Determine the current signal propagation delay Wherein, step S400 can be implemented using the following formula (3.1):

[0157]

[0158] Among them, T s =1 / f s,L , f s,L =2f s .

[0159] As can be seen from the above, in the embodiment of the present application, steps S200 and S300 use a two-dimensional unambiguous tracking technology to estimate the phase domain of the signal component instead of the power of the signal component. Compared with the ASYM-DBT technology that estimates the power of the signal component in the amplitude domain, the phase tracking accuracy of the embodiment of the present application is higher. In addition, the subcarrier frequency tracked by the existing DBT technology and ASYM-DBT technology is f s , while the signal tracking method of this application tracks twice the subcarrier frequency, i.e. 2f s Since the higher the subcarrier frequency being tracked, the higher the accuracy of the subcarrier phase ultimately obtained through phase detection, the accuracy of the subcarrier phase obtained by the signal tracking method of the present application is higher than that obtained by using the DBT technology and the ASYM-DBT technology, and the subsequent ranging accuracy based on the broadband composite signal is also higher.

[0160] In addition, if Figure 4 and Figure 5 As shown, an embodiment of the present application also provides a signal tracking device, which includes a receiving module, a carrier loop, a code loop and a subcarrier loop. The receiving module receives a broadband composite signal, which includes at least one upper sideband signal component and at least one lower sideband signal component. The carrier loop tracks the first target signal using a first local instant code to at least determine the current fusion phase and the current fusion frequency of the carrier and the subcarrier. The code loop and the subcarrier loop track the second target signal using the local instant carrier to at least determine the current code phase, the current code frequency, the current subcarrier phase and the current subcarrier frequency.

[0161] Among them, one of the first target signal and the second target signal is an upper sideband signal component, and the other is a lower sideband signal component; the first local instant code is determined based on a previous code phase and a previous code frequency, and the local instant carrier is determined based on a previous fusion phase and a previous fusion frequency.

[0162] like Figure 2 and Figure 3 As shown, different receiving module structures have different ways of receiving broadband composite signals, for example:

[0163] In the case where the receiving module includes a single signal channel 300, the receiving module uses the single signal channel 300 to synchronously receive the upper sideband signal component and the lower sideband signal component. Specifically, the center frequency of the RF front end of the receiving module is placed at the center frequency between the upper sideband signal component and the lower sideband signal component. The filter of the receiving module is a low-pass filter. The bandwidth of the low-pass filter, that is, the receiving bandwidth of the single signal channel 300, covers the power main lobe 100 of the upper sideband signal component and the power main lobe 200 of the lower sideband signal component.

[0164] In the case where the receiving module includes a first signal channel 310 and a second signal channel 320, the first signal channel 310 and the second signal channel 320 are independent of each other and are arranged in parallel, and the receiving module uses the first signal channel 310 and the second signal channel 320 to synchronously receive the upper sideband signal component and the lower sideband signal component respectively. Specifically, the center frequency point of the RF front end of the receiving module is placed at the center frequency point between the upper sideband signal component and the lower sideband signal component, the first filter of the receiving module is a bandpass filter, and the bandwidth of the first filter, that is, the receiving bandwidth of the first signal channel 310, covers the power main lobe 100 of the upper sideband signal component, and the second filter of the receiving module is also a bandpass filter, and the bandwidth of the second filter, that is, the receiving bandwidth of the second signal channel 320, covers the power main lobe 200 of the lower sideband signal component.

[0165] like Figure 4 and Figure 5 As shown, the carrier loop includes a carrier digitally controlled oscillator 400, i.e., a carrier NCO, a first correlator 410, a second correlator, and a first phase detector 430. The carrier digitally controlled oscillator 400 generates a local instantaneous carrier based on a previous fusion phase and a previous fusion frequency, and updates the previous fusion phase based on a fusion phase error to obtain a current fusion phase. The first correlator 410 calculates the product of the wideband composite signal and the local instantaneous carrier to obtain a baseband signal of a first target signal. The second correlator determines a target correlation value corresponding to the first target signal, i.e., a first correlation value and a second correlation value, based on the baseband signal of the first target signal and a first local instantaneous code. The first phase detector 430 determines a fusion phase error and a fusion frequency based on the first correlation value and the second correlation value, and feeds the fusion phase error and the fusion frequency back to the carrier digitally controlled oscillator 400.

[0166] In some embodiments, the code loop and subcarrier loop include a subcarrier digitally controlled oscillator 500 (i.e., a subcarrier NCO), a code digitally controlled oscillator 600 (i.e., a code NCO), a second phase detector 540, a third phase detector 610, a third correlator 510, and a fourth correlator. The third correlator 510 performs carrier stripping on the wideband composite signal based on the local instantaneous carrier to obtain a baseband signal of the second target signal. The subcarrier digitally controlled oscillator 500 generates a local instantaneous subcarrier based on a previous subcarrier phase and a previous subcarrier frequency, and updates the previous subcarrier phase based on a subcarrier phase error to obtain a current subcarrier phase. The code digitally controlled oscillator 600 generates a first local instantaneous code, a local advance code, a second local instantaneous code, and a local delayed code based on a previous code phase and a previous code frequency, and updates the previous code phase based on a code phase error to obtain a current code phase. The fourth correlator determines an advance correlation value, an instantaneous correlation value, and a delayed correlation value corresponding to the second target signal based on the baseband signal, the local instantaneous subcarrier, the local advance code, the second local instantaneous code, and the local delayed code of the second target signal. As an example, the advance correlation value includes a first advance correlation value and a second advance correlation value, the immediate correlation value includes a first immediate correlation value and a second immediate correlation value, and the delayed correlation value includes a first delayed correlation value and a second delayed correlation value. The second phase detector 540 determines the code phase error and the current code frequency based on the advance correlation value and the delayed correlation value, and feeds the code phase error and the current code frequency back to the code digital controlled oscillator 600. The third phase detector 610 determines the subcarrier phase error and the current subcarrier frequency based on the target correlation value and the immediate correlation value, and feeds the subcarrier phase error and the current subcarrier frequency back to the subcarrier digital controlled oscillator 500.

[0167] As an example, the first phase detector 430 may be, but is not limited to, a carrier tracking loop phase detector, the second phase detector 540 may be, but is not limited to, a code tracking loop phase detector, and the third phase detector 610 may be, but is not limited to, a subcarrier tracking loop phase detector.

[0168] Furthermore, the second correlator includes a first product correlator 421 and a first integral correlator 422 , and the fourth correlator includes a second product correlator 521 , a third product correlator 522 and a second integral correlator 530 .

[0169] The carrier digital controlled oscillator 400, the first correlator 410, the second correlator, and the first phase detector 430 are connected in sequence. The output of the receiving module is connected to the input of the first correlator 410 and the third correlator 510, respectively. The first product correlator 421 is connected to the output of the code digital controlled oscillator 600 and is used to receive the first local instantaneous code generated by the code digital controlled oscillator 600 to calculate the product of the baseband signal of the first target signal and the first local instantaneous code. The input of the first integrating correlator 422 is connected to the output of the first product correlator 421 and is used to integrate the product of the baseband signal of the first target signal and the first local instantaneous code within a first integration interval to obtain a first correlation value and a second correlation value. The output of the first integrating correlator 422 is connected to the input of the first phase detector 430 and the input of the third phase detector 610, respectively. The output of the first phase detector 430 is connected to the input of the carrier digital controlled oscillator 400. The output end of the carrier digital controlled oscillator 400 is connected to the input end of the third correlator 510. The third correlator 510 performs carrier stripping on the broadband composite signal based on the local instantaneous carrier generated by the carrier digital controlled oscillator 400 to obtain the baseband signal of the second target signal; the second product correlator 521 is connected to the output end of the subcarrier digital controlled oscillator 500 and the output end of the third correlator 510 respectively, and is used to receive the local instantaneous subcarrier generated by the subcarrier digital controlled oscillator 500 and calculate the product of the local instantaneous subcarrier and the baseband signal of the second target signal; the input end of the third product correlator 522 is connected to the output end of the second product correlator 521 and the output end of the code digital controlled oscillator 600 respectively, and is used to calculate the product of the local advance code, the second local instantaneous code and the local delayed code generated by the code digital controlled oscillator 600 and the output value of the second product correlator 521 respectively. The input of the second integrating correlator 530 is connected to the input of the third product correlator 522, and is configured to integrate the output value of the second product correlator 521 in a second integration interval to obtain a first early correlation value, a second early correlation value, a first immediate correlation value, a second immediate correlation value, a first delayed correlation value, and a second delayed correlation value. The output of the second integrating correlator 530 is connected to the inputs of the second phase detector 540 and the third phase detector 610, respectively. The output of the second phase detector 540 is connected to the input of the code digital controlled oscillator 600, and the output of the third phase detector 610 is connected to the input of the subcarrier digital controlled oscillator 500.

[0170] The following takes the first type of signal to be tracked mentioned above as an example, that is, the signal to be tracked r I (t) is r UI (t)+r LI (t), the reference phase is the upper sideband signal component r UI Phase φ of (t) UI(t) as an example to illustrate the working principle of the carrier loop:

[0171] like Figure 4 and Figure 5 As shown, the carrier digital controlled oscillator 400 is based on the previous fusion phase and the previous fusion frequency f UI Generate local instant carrier The first correlator 410 generates a signal r to be tracked according to the output of the receiving module. I (t) and the local instantaneous carrier output by the carrier digitally controlled oscillator 400 Calculate the baseband signal s of the first target signal UI (t-τ); The first product correlator 421 is based on the baseband signal s of the first target signal UI (t-τ) and the first local instant code generated by the code digital controlled oscillator 600 Calculate the baseband signal s of the first target signal UI (t-τ) and the first local instant code The first integral correlator 422 calculates the baseband signal s of the first target signal in the first integral interval [0, T]. UI (t-τ) and the first local instant code Integrate the product of to obtain the first correlation value I UI,P and the second correlation value Q UI,P The first phase detector 430 is based on the first correlation value I UI,P and the second correlation value Q UI,P Phase detection is performed and the fusion phase error Δγ and the current fusion frequency obtained by the phase detection are output to the carrier digital controlled oscillator 400. The carrier digital controlled oscillator 400 updates the previous fusion phase according to the fusion phase error to obtain the current fusion phase. The fusion phase and fusion frequency can be used as the previous fusion phase and previous fusion frequency required for the next tracking cycle respectively.

[0172] Similarly, the carrier digitally controlled oscillator 400 generates the local instantaneous carrier The data is transmitted to the third correlator 510, which calculates the local instantaneous carrier and the signal to be tracked r I (t) to obtain the baseband signal s of the second target signal LI (t-τ). The subcarrier digital controlled oscillator 500 will be based on the previous subcarrier phase and the previous subcarrier frequency Generated local instantaneous subcarrier sc LI (t) is transmitted to the second product correlator 521, which calculates the baseband signal s of the second target signalLI (t-τ) and the local instantaneous subcarrier sc LI The code digital controlled oscillator 600 will be based on the previous code phase and the previous code frequency to generate the local advance code Second local instant code and local delay code The local advance code is transmitted to the third product correlator 522, and the third product correlator 522 calculates the local advance code Second local instant code and local delay code The second integral correlator 530 integrates the input value of the second product correlator 521 in the second integral interval to determine the first early correlation value I LI,E , the second advance correlation value Q LI,E , the first instantaneous correlation value I LI,P , the second immediate correlation value Q LI,p , first delay related value I LI,L and the second delayed correlation value Q LI,L The second phase detector 540 is based on the first advance correlation value I LI,E , the second advance correlation value Q LI,E , first delay related value I LI,L and the second delayed correlation value Q LI,L Perform phase detection to determine the code phase error and the current code frequency, and the code phase error The current code frequency is fed back to the code digital controlled oscillator 600. The code digital controlled oscillator 600 is fed back to the code digital controlled oscillator 600 according to the code phase error. Update the previous code phase The third phase detector 610 obtains the current code phase, which can be used as the previous code phase and the previous code frequency required for the next tracking cycle. UI,P , the second correlation value Q UI,P , the first instantaneous correlation value I LI,P , the second immediate correlation value Q LI,p Phase detection is performed to determine the subcarrier phase error Δμ and the current subcarrier frequency, and the subcarrier phase error Δμ and the current subcarrier frequency are fed back to the subcarrier digital controlled oscillator 500. The subcarrier digital controlled oscillator 500 updates the previous subcarrier phase according to the subcarrier phase error Δμ. To obtain the current subcarrier phase, the subcarrier phase and subcarrier frequency can be used as the previous subcarrier phase and previous subcarrier frequency required for the next tracking cycle respectively.

[0173] In addition, the signal tracking device further includes a delay calculation module, which is used to determine the current signal propagation delay according to the current code phase, the current subcarrier phase and the current subcarrier frequency.

[0174] The following simulation test is performed using the signal tracking device in the embodiment of the present application:

[0175] As shown in Table 1, this simulation test targets the ACE-BOC broadband composite signal superimposed with white noise of different powers, and the signal to be tracked is still r I (t), the reference phase is the upper sideband signal component r UI Phase φ of (t) UI (t).

[0176] Table 1 Parameters of ACE-BOC broadband composite signal

[0177] parameter Parameter value Satellite number C19 IF frequency 0MHz Data format I&Q Sampling rate 60MHz Carrier-to-noise ratio 40~50dB-Hz <![CDATA[Signal component power ratio (P LI :P LQ :P UI :P UQ )]]> 1:1.2:0.5:1.4

[0178] As shown in Table 2, the carrier loop is a phase-locked loop (PLL), the code loop is a digital delay lock loop (DLL), and the subcarrier loop is a subcarrier tracking loop (SLL).

[0179] Table 2 Parameters of carrier loop, code loop and subcarrier loop

[0180] parameter Parameter value PLL order 2 PLL loop filter bandwidth 5Hz DLL order 2 DLL loop filter bandwidth 1 / 2 / 5Hz DLL early and late interval 0.5 chips SLL order 2 SLL loop filter bandwidth 1 / 2 / 5Hz Coherent integration time T 1ms

[0181] like Figure 6 As shown, through simulation experiments, it is found that the carrier-to-noise ratio generated by the signal tracking method in the embodiment of the present application is substantially the same as the carrier-to-noise ratio generated by the existing BPSK-Like tracking technology. UI (t) and the lower sideband signal component r LI (t) are tracked as separate signals, and this application is to track the upper sideband signal component r UI (t) and the lower sideband signal component r LI (t) Joint tracking is performed simultaneously, so the carrier-to-noise ratio of the two is basically the same, which indirectly shows that the signal tracking method of the present application has strong stability.

[0182] In addition, if Figure 7 As shown, the signal tracking method of the present application tracks twice the subcarrier frequency, i.e., 2f s , the lower sideband signal component r LIThe autocorrelation function envelope of (t) is consistent with the autocorrelation function envelope of the BPSK signal, which also shows that the subcarrier phase and code phase obtained by the signal tracking method of the present application are highly accurate.

[0183] In addition, if Figure 8 As shown in FIG, through simulation experiments, it is found that under different loop filter bandwidths, the thermal noise performance of the signal tracking method in the embodiment of the present application is better than the thermal noise performance generated by the existing BPSK-Like tracking technology. Compared with the BPSK-Like tracking technology, the tracking error of the signal tracking method in the embodiment of the present application is smaller. In addition, as Figure 9 As shown, when the loop bandwidth is 5 Hz and the carrier-to-noise ratio is 50 dB-Hz, the code minus carrier (CMC) fluctuation of the signal tracking method in the embodiment of the present application is smaller than that of the BPSK-Like tracking technology. It can be seen that the signal tracking method in the embodiment of the present application can improve the ranging accuracy.

[0184] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in this application can be achieved. This is not a limitation herein.

[0185] The above specific embodiments do not limit the scope of protection of this application. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application shall be included within the scope of protection of this application.

Claims

1. A signal tracking method, characterized in that: include: Receive a broadband composite signal; wherein the broadband composite signal includes at least one upper sideband signal component and at least one lower sideband signal component; Tracking the first target signal using the first local instant code to determine at least a current fusion phase and a current fusion frequency of the carrier and the subcarrier; and Tracking the second target signal using the local instantaneous carrier to determine at least a current code phase, a current code frequency, a current subcarrier phase, and a current subcarrier frequency; Among them, one of the first target signal and the second target signal is the upper sideband signal component, and the other is the lower sideband signal component; the first local instant code is determined based on the previous code phase and the previous code frequency, and the local instant carrier is determined based on the previous fusion phase and the previous fusion frequency.

2. The signal tracking method according to claim 1, wherein: Receives wideband composite signals including: Using a single signal channel to simultaneously receive the upper sideband signal component and the lower sideband signal component; The receiving bandwidth of the single signal channel covers the power main lobe of the upper sideband signal component and the power main lobe of the lower sideband signal component.

3. The signal tracking method according to claim 1, wherein: Receives wideband composite signals including: Using a first signal channel to receive the upper sideband signal component; wherein the receiving bandwidth of the first signal channel covers the power main lobe of the upper sideband signal component; and The lower sideband signal component is received using a second signal channel that is independent of and arranged in parallel with the first signal channel; wherein the receiving bandwidth of the second signal channel covers the power main lobe of the lower sideband signal component.

4. The signal tracking method according to any one of claims 1 to 3, wherein: Tracking the first target signal using the first local instant code to determine at least a current fusion phase and a current fusion frequency of the carrier and the subcarrier includes: performing carrier stripping on the broadband composite signal based on the previous fusion phase and the previous fusion frequency to obtain a baseband signal of the first target signal; determining a target correlation value corresponding to the first target signal based on the baseband signal of the first target signal and the first local instant code; Performing phase discrimination according to the target correlation value to determine a fusion phase error and the current fusion frequency; and The previous fusion phase is updated according to the fusion phase error to obtain the current fusion phase.

5. The signal tracking method according to claim 4, wherein: Performing carrier stripping on the broadband composite signal based on the previous fusion phase and the previous fusion frequency to obtain a baseband signal of the first target signal includes: generating a local instantaneous carrier wave using a carrier digitally controlled oscillator according to the previous fusion phase and the previous fusion frequency; and A product of the broadband composite signal and the local instantaneous carrier is calculated to obtain a baseband signal of the first target signal. The signal tracking method according to claim 4 , wherein: Determining a target correlation value corresponding to the first target signal according to the baseband signal of the first target signal and the first local instant code includes: The product of the baseband signal of the first target signal and the first local prompt code is integrated within a first integration interval to obtain the target correlation value.

7. The signal tracking method according to claim 4, wherein: Tracking the second target signal using the local instantaneous carrier to determine at least a current code phase, a current code frequency, a current subcarrier phase, and a current subcarrier frequency includes: performing carrier stripping on the broadband composite signal based on the local instantaneous carrier to obtain a baseband signal of the second target signal; determining an advanced correlation value, an immediate correlation value, and a delayed correlation value corresponding to the second target signal according to a baseband signal of the second target signal, a previous code phase, a previous code frequency, a previous subcarrier phase, and a previous subcarrier frequency; Perform phase detection according to the advance correlation value and the delay correlation value to determine a code phase error and the current code frequency; Updating the previous code phase according to the code phase error to obtain a current code phase; Performing phase discrimination according to the target correlation value and the instantaneous correlation value to determine a subcarrier phase error and the current subcarrier frequency; and The previous subcarrier phase is updated according to the subcarrier phase error to obtain the current subcarrier phase.

8. The signal tracking method according to claim 7, wherein: Determining an early correlation value, an immediate correlation value, and a delayed correlation value corresponding to the second target signal according to a baseband signal of the second target signal, a previous code phase, a previous code frequency, a previous subcarrier phase, and a previous subcarrier frequency, comprising: Generate a first local prompt code, a local advance code, a second local prompt code, and a local delay code according to the previous code phase and the previous code frequency using a code digitally controlled oscillator; generating a local prompt subcarrier using a subcarrier digitally controlled oscillator based on a previous subcarrier phase and a previous subcarrier frequency; and The advance correlation value, the prompt correlation value, and the delay correlation value are determined according to a baseband signal of the second target signal, the local prompt subcarrier, the local advance code, the second local prompt code, and the local delay code.

9. The signal tracking method according to claim 8, wherein: Determining the advance correlation value, the immediate correlation value, and the delayed correlation value according to a baseband signal of the second target signal, the local immediate subcarrier, the local advance code, the second local immediate code, and the local delay code comprises: Integrating a product of a baseband signal of the second target signal, the local prompt subcarrier, and the local advance code in a second integration interval to obtain the advance correlation value; Integrating the product of the baseband signal of the second target signal, the local prompt subcarrier, and the second local prompt code in the second integration interval to obtain the prompt correlation value; and The product of the baseband signal of the second target signal, the local prompt subcarrier, and the local delay code is integrated in the second integration interval to obtain the delay correlation value.

10. The signal tracking method according to any one of claims 1 to 3, wherein: After receiving the local instantaneous carrier and tracking another signal component in the broadband composite signal as a second target signal, the signal tracking method further includes: A current signal propagation delay is determined according to the current code phase, the current subcarrier phase, and the current subcarrier frequency.

11. A signal tracking device, characterized in that: include: A receiving module receives a broadband composite signal; wherein the broadband composite signal includes at least one upper sideband signal component and at least one lower sideband signal component; The carrier loop tracks the first target signal using the first local instant code to determine at least a current fusion phase and a current fusion frequency of the carrier and the subcarrier; and The code loop and the subcarrier loop track the second target signal using the local instantaneous carrier to determine at least a current code phase, a current code frequency, a current subcarrier phase, and a current subcarrier frequency; Among them, one of the first target signal and the second target signal is the upper sideband signal component, and the other is the lower sideband signal component; the first local instant code is determined based on the previous code phase and the previous code frequency, and the local instant carrier is determined based on the previous fusion phase and the previous fusion frequency.

12. The signal tracking device according to claim 11, wherein: The receiving module includes a single signal channel, and the receiving bandwidth of the single signal channel covers the power main lobe of the upper sideband signal component and the power main lobe of the lower sideband signal component.

13. The signal tracking device according to claim 11, wherein: The receiving module includes a first signal channel and a second signal channel, the first signal channel and the second signal channel are independent of each other and are arranged in parallel; the receiving bandwidth of the first signal channel covers the power main lobe of the upper sideband signal component, and the receiving bandwidth of the second signal channel covers the power main lobe of the lower sideband signal component.

14. The signal tracking device according to any one of claims 11 to 13, wherein: The carrier loop includes: a carrier digitally controlled oscillator, generating a local instantaneous carrier according to a previous fusion phase and a previous fusion frequency, and updating the previous fusion phase according to a fusion phase error to obtain a current fusion phase; a first correlator, calculating a product of the broadband composite signal and the local instantaneous carrier to obtain a baseband signal of the first target signal; a second correlator, determining a target correlation value corresponding to the first target signal based on the baseband signal of the first target signal and the first local instant code; The first phase detector determines the fusion phase error and the current fusion frequency according to the target correlation value and feeds the fusion phase error and the current fusion frequency back to the carrier digitally controlled oscillator.

15. The signal tracking device according to claim 14, wherein: The code loop and the subcarrier loop include: a third correlator, performing carrier stripping on the broadband composite signal based on the local instantaneous carrier to obtain a baseband signal of the second target signal; a subcarrier digitally controlled oscillator for generating a local instantaneous subcarrier according to a previous subcarrier phase and a previous subcarrier frequency, and for updating the previous subcarrier phase according to a subcarrier phase error to obtain a current subcarrier phase; a code digitally controlled oscillator, generating a first local prompt code, a local advance code, a second local prompt code, and a local delay code according to a previous code phase and a previous code frequency, and updating the previous code phase according to a code phase error to obtain a current code phase; a fourth correlator, configured to determine an advance correlation value, an immediate correlation value, and a delayed correlation value corresponding to the second target signal based on the baseband signal of the second target signal, the local immediate subcarrier, the local advance code, the second local immediate code, and the local delayed code; a second phase detector, determining the code phase error and the current code frequency according to the advance correlation value and the delay correlation value, and feeding the code phase error and the current code frequency back to the code digital controlled oscillator; A third phase detector determines the subcarrier phase error and the current subcarrier frequency according to the target correlation value and the instantaneous correlation value, and feeds the subcarrier phase error and the current subcarrier frequency back to the subcarrier digitally controlled oscillator.

16. The signal tracking device according to claim 15, wherein: The first phase detector is a carrier tracking loop phase detector, the second phase detector is a code tracking loop phase detector and / or the third phase detector is a subcarrier tracking loop phase detector.

17. The signal tracking device according to any one of claims 11 to 13, further comprising: The delay calculation module determines a current signal propagation delay according to the current code phase, the current subcarrier phase and the current subcarrier frequency.

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