Cross-aided dual-frequency signal carrier phase joint tracking method and device

Abstract

The application discloses a kind of cross-assisted dual-frequency signal carrier phase joint tracking method and device, it is related to communication, navigation technical field, including: receiving the same satellite dual-frequency signal and processing as digital intermediate frequency signal;Respectively to each frequency point signal is carried out carrier stripping, pseudo code stripping, integral zero and phase discrimination processing, and phase discrimination result is obtained;Each frequency point phase discrimination result is multiplied by proportionality factor, and cross generation is the carrier phase tracking auxiliary quantity of another frequency point;The phase discrimination result of this frequency point is input into double-input port filter with auxiliary quantity, and carrier frequency estimation is generated;Accordingly, local carrier signal is generated, and closed loop tracking is formed.The transfer function of two input ports of double-input port filter is shared digital register unit when being realized.The application decomposes traditional joint filter function into each frequency point filter, eliminates the pole of transfer function at the origin, while maintaining joint tracking accuracy and reducing threshold advantage, simplifies architecture and improves tracking robustness.

Description

Technical Field

[0001] This invention relates to the fields of communication and navigation technology, and in particular to a cross-assisted dual-frequency signal carrier phase joint tracking method and apparatus. Background Technology

[0002] Global Navigation Satellite Systems (GNSS) typically broadcast navigation signals on multiple frequencies. For example, GPS broadcasts navigation signals on L1, L2, and L5 frequencies, the BeiDou Navigation Satellite System (BDS) broadcasts navigation signals on B1, B2, and B3 frequencies, and the Galileo system broadcasts navigation signals on E1, E5, and E6 frequencies. To fully utilize the characteristic of GNSS systems broadcasting multiple signals simultaneously, researchers have proposed a method for jointly tracking multiple GNSS signals. By aggregating the power of each signal, the carrier phase tracking performance of each signal can be improved.

[0003] Existing dual-frequency or multi-frequency carrier phase joint tracking methods mostly employ a joint tracking architecture that combines joint filtering at multiple frequencies with individual filtering at each frequency. For example, Chinese invention patent CN116973949A and Bolla P et al.'s publications "Centralized dynamics multi-frequency GNSS carrier synchronization" (NAVIGATION, 2019, 66: 485–504) and "Joint Tracking of Multiple Frequency Signals from the same GNSS satellite" (2018 8th International Conference on Localization and GNSS (ICL-GNSS), 2018, pp. 1-6) both disclose this architecture, which includes a joint filter and individual filters for each frequency. A schematic diagram of the dual-frequency carrier phase joint tracking architecture is shown below. Figure 3 As shown, this architecture requires three independent filters, making it complex. When a state in the joint filter or the digital register unit storing that state is disturbed, joint tracking instability can easily occur. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention aims to provide a cross-assisted dual-frequency signal carrier phase joint tracking method and apparatus, which, while maintaining the advantages of joint tracking in improving carrier phase tracking accuracy and reducing the carrier phase tracking threshold, reduces the complexity of the joint tracking architecture and improves the robustness of joint tracking.

[0005] To achieve the above-mentioned objective, this invention provides a cross-assisted dual-frequency signal carrier phase joint tracking method, comprising the following steps:

[0006] Step S1: Simultaneously receive a first frequency signal and a second frequency signal from the same satellite, and process the first frequency signal and the second frequency signal into a first frequency digital intermediate frequency signal and a second frequency digital intermediate frequency signal, respectively.

[0007] Step S2: Perform carrier stripping, pseudocode stripping, integration zeroing and phase detection processing on the first frequency digital intermediate frequency signal and the second frequency digital intermediate frequency signal respectively to obtain the phase detection result of the first frequency point and the phase detection result of the second frequency point.

[0008] Step S3: Multiply the phase detection result of the first frequency point by the first scaling factor to obtain the second frequency point carrier phase tracking auxiliary amount used to assist the second frequency point tracking; multiply the phase detection result of the second frequency point by the second scaling factor to obtain the first frequency point carrier phase tracking auxiliary amount used to assist the first frequency point tracking.

[0009] Step S4: Input the phase detection result of the first frequency point and the carrier phase tracking auxiliary quantity of the first frequency point together into the first dual-input port filter to generate the carrier frequency estimate of the first frequency point; input the phase detection result of the second frequency point and the carrier phase tracking auxiliary quantity of the second frequency point together into the second dual-input port filter to generate the carrier frequency estimate of the second frequency point.

[0010] Step S5: Generate a first local carrier signal using the first frequency point carrier frequency estimate, the first local carrier signal being used to perform carrier stripping on the first frequency point digital intermediate frequency signal; generate a second local carrier signal using the second frequency point carrier frequency estimate, the second local carrier signal being used to perform carrier stripping on the second frequency point digital intermediate frequency signal.

[0011] According to one technical solution of the present invention, the first frequency signal and the second frequency signal are signals with different carrier frequencies transmitted by the same satellite.

[0012] According to a technical solution of the present invention, step S2 specifically includes:

[0013] Step S21: Mix the first frequency digital intermediate frequency signal with the first local carrier signal to remove the carrier and obtain the first frequency baseband signal; mix the second frequency digital intermediate frequency signal with the second local carrier signal to remove the carrier and obtain the second frequency baseband signal.

[0014] Step S22: Perform pseudocode stripping on the first frequency baseband signal to obtain the pseudocode stripped signal at the first frequency; perform pseudocode stripping on the second frequency baseband signal to obtain the pseudocode stripped signal at the second frequency.

[0015] Step S23: Perform integration and zeroing on the signal after stripping the pseudocode at the first frequency point to obtain the correlation integration result of the first frequency point; perform integration and zeroing on the signal after stripping the pseudocode at the second frequency point to obtain the correlation integration result of the second frequency point;

[0016] Step S24: Perform phase detection on the correlation integration result of the first frequency point to obtain the phase detection result of the first frequency point; perform phase detection on the correlation integration result of the second frequency point to obtain the phase detection result of the second frequency point.

[0017] According to one technical solution of the present invention, both the first scaling factor and the second scaling factor are real numbers greater than zero.

[0018] According to one technical solution of the present invention, in step S4, both the first dual-input port filter and the second dual-input port filter are filters having a first input port and a second input port; wherein, the first input port is used to input the phase detection result of the current frequency point, and the second input port is used to input the carrier phase tracking auxiliary quantity generated by the phase detection result of another frequency point for assisting the tracking of the current frequency point;

[0019] For the first dual-input port filter, its first input port to output port has a first transfer function H1(z), and its second input port to output port has a second transfer function H2(z); the implementation of the first transfer function H1(z) and the implementation of the second transfer function H2(z) share a digital register unit.

[0020] According to one technical solution of the present invention, for the second dual-input port filter, its first input port to output port has a third transfer function, and its second input port to output port has a fourth transfer function; the implementation of the third transfer function and the implementation of the fourth transfer function share a digital register unit.

[0021] According to one technical solution of the present invention, the total number N of digital register units required to construct a dual-input port filter satisfies N=max(N1,N2), where N1 is the number of first digital register units required to implement the first transfer function H1(z), and N2 is the number of second digital register units required to implement the second transfer function H2(z);

[0022] The total number of digital register units M required to construct the second dual-input port filter satisfies M = max(M1,M2), where M1 is the number of third digital register units required to construct the third transfer function H3(z), and M2 is the number of fourth digital register units required to construct the fourth transfer function H4(z).

[0023] According to one technical solution of the present invention, step S5 specifically includes:

[0024] Step S51: Update the first numerically controlled oscillator using the first frequency point carrier frequency estimate to generate the first frequency point local carrier phase estimate; update the second numerically controlled oscillator using the second frequency point carrier frequency estimate to generate the second frequency point local carrier phase estimate.

[0025] Step S52: Generate the first local carrier signal using the local carrier phase estimation at the first frequency point; generate the second local carrier signal using the local carrier phase estimation at the second frequency point.

[0026] According to one aspect of the present invention, a cross-assisted dual-frequency signal carrier phase joint tracking device is provided, comprising:

[0027] The receiver antenna is used to simultaneously receive signals from the first and second frequency points of the same satellite.

[0028] The downconversion module is used to perform downconversion processing on the first frequency signal and the second frequency signal to generate a first frequency digital intermediate frequency signal and a second frequency digital intermediate frequency signal respectively.

[0029] The phase detection module is used to perform carrier stripping, pseudocode stripping, integration zeroing and phase detection processing on the first frequency digital intermediate frequency signal and the second frequency digital intermediate frequency signal, respectively, to obtain and output the phase detection result of the first frequency and the phase detection result of the second frequency.

[0030] The first frequency point dual-input port filtering module is used to receive the first frequency point phase detection result, and to receive the first frequency point carrier phase tracking auxiliary quantity obtained by multiplying the second frequency point phase detection result by the first scaling factor, and to generate the first frequency point carrier frequency estimate.

[0031] The second frequency point dual-input port filtering module is used to receive the second frequency point phase detection result, and to receive the second frequency point carrier phase tracking auxiliary quantity obtained by multiplying the first frequency point phase detection result by the second scaling factor, and to generate the second frequency point carrier frequency estimate.

[0032] The first frequency point local carrier signal generation module is used to generate a first local carrier signal based on the first frequency point carrier frequency estimate. The first local carrier signal is used to perform carrier stripping on the first frequency point digital intermediate frequency signal.

[0033] The second frequency point local carrier signal generation module is used to generate a second local carrier signal based on the second frequency point carrier frequency estimate. The second local carrier signal is used to perform carrier stripping on the second frequency point digital intermediate frequency signal.

[0034] According to one technical solution of the present invention, the phase detection module includes:

[0035] The carrier stripping submodule is used to mix the first frequency digital intermediate frequency signal with the first local carrier signal to obtain the first frequency baseband signal; and to mix the second frequency digital intermediate frequency signal with the second local carrier signal to obtain the second frequency baseband signal.

[0036] The pseudocode stripping submodule is used to strip pseudocode from the baseband signal at the first frequency point to obtain the pseudocode stripped signal at the first frequency point; and to strip pseudocode from the baseband signal at the second frequency point to obtain the pseudocode stripped signal at the second frequency point.

[0037] The integration zeroing submodule is used to perform integration zeroing on the signal after stripping the pseudocode at the first frequency point to obtain the integration result related to the first frequency point; and to perform integration zeroing on the signal after stripping the pseudocode at the second frequency point to obtain the integration result related to the second frequency point.

[0038] The phase detection submodule is used to perform phase detection on the correlation integration result of the first frequency point to obtain the phase detection result of the first frequency point; and to perform phase detection on the correlation integration result of the second frequency point to obtain the phase detection result of the second frequency point.

[0039] Compared with the prior art, the cross-assisted dual-frequency signal carrier phase joint tracking method and apparatus provided by the present invention have the following significant technical effects:

[0040] By cross-coupling the phase detection results at the first and second frequencies, carrier phase tracking auxiliary quantities are generated for each frequency. A dual-input port filter is then used to jointly filter the phase detection results and auxiliary quantities at each frequency. This architecture decomposes the independent joint filter function found in traditional joint tracking schemes and integrates it into the filters at each frequency, achieving effective fusion of dual-frequency signal information without the need for a separate joint filter.

[0041] In terms of stability, the dual-input port filter shares digital register units in its hardware and software implementation, allowing the signals from the two input ports to be processed in the same dynamic system. This eliminates the poles of the transfer function at the origin in the original architecture from the system model level, thereby eradicating the problem of individual filter output divergence in conventional joint tracking schemes and improving the global stability and robustness to transient disturbances of the joint tracking loop.

[0042] In terms of tracking performance, this invention maintains the advantages of joint tracking, such as improved carrier phase tracking accuracy and reduced carrier phase tracking threshold, while simplifying the complexity of the joint tracking architecture and reducing hardware resource overhead through the compact structure of shared registers. When the signal quality at a certain frequency temporarily degrades, auxiliary information from another frequency can smoothly support the continuous tracking of weak signal loops through cross-branching, avoiding loop lockout caused by divergence of individual filter outputs, thereby shortening the signal recovery time and ensuring the continuity of the receiver's positioning service in complex environments. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0044] Figure 1 The schematic diagram illustrates a flow chart of a cross-assisted dual-frequency signal carrier phase joint tracking method according to the present invention;

[0045] Figure 2 A schematic diagram illustrating the configuration of a cross-assisted dual-frequency signal carrier phase joint tracking device according to one embodiment of the present invention;

[0046] Figure 3 A schematic diagram illustrating the configuration of a conventional dual-frequency signal carrier phase joint tracking device;

[0047] Figure 4 A schematic diagram illustrating one embodiment of the dual-input port filter of the present invention;

[0048] Figure 5 The diagram illustrates a mathematical model of a cross-assisted joint tracking method according to one embodiment of the present invention. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other. The following embodiments only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be pointed out that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of this application, and these all fall within the protection scope of this application.

[0051] like Figures 1 to 5 As shown, a cross-assisted dual-frequency signal carrier phase joint tracking method of the present invention includes the following steps:

[0052] Step S1: Simultaneously receive a first frequency signal and a second frequency signal from the same satellite, and process the first frequency signal and the second frequency signal into a first frequency digital intermediate frequency signal and a second frequency digital intermediate frequency signal, respectively.

[0053] The first and second frequency signals are transmitted from the same satellite at different carrier frequencies. and After receiving the signal, the local oscillator signal is mixed, filtered, and sampled by the downconversion module of each channel to generate the first frequency digital intermediate frequency signal and the second frequency digital intermediate frequency signal.

[0054] Step S2: Perform carrier stripping, pseudocode stripping, integration zeroing, and phase detection processing on the first frequency digital intermediate frequency signal and the second frequency digital intermediate frequency signal respectively to obtain the phase detection result of the first frequency point and the phase detection result of the second frequency point, specifically including:

[0055] Step S21: Combine the digital intermediate frequency signals of the first and second frequency points with their respective local carrier signals. Frequency mixing involves stripping the carrier wave to generate baseband signals for each frequency point. ,in, Indicates the first One frequency point, , A positive integer, representing the first... One data point;

[0056] Step S22: For the baseband signal at each frequency point Perform pseudocode stripping to generate signals for each frequency point after pseudocode stripping. Pseudocode stripping involves performing correlation operations between the locally generated spreading code and the baseband signal to further remove spreading code modulation.

[0057] Step S23: Strip the pseudocode from the signal at each frequency point. By resetting the integral to zero, the relevant integral results for each frequency point are obtained. Integral zeroing is the process of accumulating the signal over a relevant integration time period to improve the signal-to-noise ratio.

[0058] Step S24: Correlation integration results for each frequency point Phase detection is performed, and phase detection results for each frequency point are generated accordingly. Phase detection can be performed using an arctangent phase detector or a dot product phase detector, etc., to extract the carrier phase error from the relevant integration results.

[0059] After the above processing, the phase detection results at the first frequency point and the phase detection results at the second frequency point are obtained.

[0060] Step S3: Multiply the phase detection results of the first and second frequency points by their respective scaling factors to obtain the carrier phase tracking auxiliary quantities for the corresponding second and first frequency points, respectively.

[0061] Specifically, such as Figure 2 and Figure 5 As shown, the phase detection result of the first frequency point is multiplied by the first scaling factor to obtain the second frequency point carrier phase tracking auxiliary quantity used to assist the tracking of the second frequency point; the phase detection result of the second frequency point is multiplied by the second scaling factor to obtain the first frequency point carrier phase tracking auxiliary quantity used to assist the tracking of the first frequency point. Both the first and second scaling factors are real numbers greater than zero, and their values ​​can be determined based on the carrier frequency relationship between the two frequency points.

[0062] Setting the scaling factor allows phase error information from another frequency point to be coupled into the tracking loop of this frequency point at the correct scale, thereby achieving effective fusion of carrier dynamic information from two frequencies without a joint filter.

[0063] Step S4: The phase detection results of the first and second frequency points, along with their respective auxiliary tracking values, are input to their respective dual-input port filters to generate carrier frequency estimates for the first and second frequency points. .

[0064] like Figure 5 As shown, it is the mathematical model of the phase detection filtering module of the cross-assisted dual-frequency signal carrier phase joint tracking method.

[0065] The phase detection result at the first frequency point and the carrier phase tracking auxiliary quantity at the first frequency point are respectively input to the first input port and the second input port of the first dual-input port filter. The filter outputs the carrier frequency estimate at the first frequency point. The phase detection result at the second frequency point and the carrier phase tracking auxiliary quantity at the second frequency point are respectively input to the first input port and the second input port of the second dual-input port filter. The filter outputs the carrier frequency estimate at the second frequency point. .

[0066] A dual-input port filter has two transfer functions: H1(z) from input port 1 to output port and H2(z) from input port 2 to output port. In hardware and software implementation, these two transfer functions share digital register units. That is, the total number of digital register units used to construct the dual-input port filter is N = max(N1, N2), where N1 is the number of digital register units used to construct H1(z) and N2 is the number of digital register units used to construct H2(z).

[0067] The total number of digital register units M required to construct the second dual-input port filter satisfies M = max(M1,M2), where M1 is the number of third digital register units required to construct the third transfer function H3(z), and M2 is the number of fourth digital register units required to construct the fourth transfer function H4(z).

[0068] By using shared registers, not only are hardware resources saved, but more importantly, potential unstable poles caused by the separation of state variables in individual / joint filters are avoided.

[0069] The shared register structure allows the phase detection results from the local frequency and the phase detection results from another frequency after scaling to be processed jointly in the same dynamic system. The historical states of both are stored in the same set of registers, which mathematically eliminates the poles of the transfer function at the origin, avoids the problem of output divergence of individual filters or joint filters in conventional joint tracking architectures, and ensures the global stability of the loop.

[0070] Step S5: Estimation of carrier frequencies at the first and second frequency points The signals are input to their respective numerically controlled oscillators to generate local carrier signals for carrier stripping. .

[0071] Using the carrier frequency estimate at the first frequency point Update the first numerically controlled oscillator to generate the first local carrier signal. The first local carrier signal is used to perform carrier stripping on the first frequency point digital intermediate frequency signal; the second numerically controlled oscillator is updated using the second frequency point carrier frequency estimate. A second local carrier signal is generated, which is used to perform carrier stripping on the digital intermediate frequency signal at the second frequency point. .

[0072] Then, local carrier phase estimation is used at each frequency point. Generate local carrier signals for each frequency point. This information is fed back to step S21 for the next carrier stripping. This constitutes the carrier phase closed-loop tracking loop for the dual-frequency signal.

[0073] The phase detection results of the first and second frequency points are used for tracking filtering at the current frequency point, and after proportional transformation, they are cross-assisted for tracking filtering at another frequency point, eliminating the need for a separate joint filter. Compared with known GNSS carrier phase joint tracking methods, this invention maintains the advantages of joint tracking in improving carrier phase tracking accuracy and lowering the carrier phase tracking threshold, while reducing the complexity of the joint tracking architecture and improving the robustness of joint tracking.

[0074] Figure 2 This diagram schematically illustrates the configuration of a cross-assisted dual-frequency signal carrier phase joint tracking device according to one embodiment of the present invention. The device includes a receiver antenna, a down-conversion module, a phase detection module, a first-frequency dual-input port filtering module, a second-frequency dual-input port filtering module, a first-frequency local carrier signal generation module, and a second-frequency local carrier signal generation module.

[0075] Receiver antenna, used to receive carrier frequencies of and The downconversion module performs downconversion processing on the received first and second frequency signals respectively to generate digital intermediate frequency signals for the first and second frequency points.

[0076] The phase detection module includes a carrier stripping submodule, a pseudocode stripping submodule, an integral clearing submodule, and a phase detection submodule. The carrier stripping submodule compares the digital intermediate frequency signals of the first and second frequency points with their respective local carrier signals. Frequency mixing involves stripping the carrier wave to generate the corresponding baseband signal. The pseudocode stripping submodule performs pseudocode stripping on each baseband signal, generating the pseudocode-stripped signal. The integration zeroing submodule integrates and zeroes the signal after pseudocode stripping, obtaining the relevant integration results. The phase detection submodule performs phase detection on each relevant integration result and outputs the phase detection result at the first frequency point. Phase detection results at the second frequency point .

[0077] like Figure 2 and Figure 5As shown, the first frequency point dual-input port filtering module includes a first frequency point auxiliary term generation submodule and a first frequency point local carrier frequency estimation submodule. The first frequency point auxiliary term generation submodule uses the phase detection result of the second frequency point... Multiplying this by the second scaling factor yields the carrier phase tracking auxiliary value for the first frequency point. The local carrier frequency estimation submodule for the first frequency point receives the phase detection result for the first frequency point. The carrier phase tracking auxiliary quantity at the first frequency point is input to the two input terminals of the first dual-input port filter to generate the carrier frequency estimate at the first frequency point. .

[0078] The second-frequency dual-input port filtering module includes a second-frequency auxiliary term generation submodule and a second-frequency local carrier frequency estimation submodule. The second-frequency auxiliary term generation submodule uses the phase detection result from the first frequency point... Multiplying this by the first scaling factor yields the carrier phase tracking auxiliary value for the second frequency point. The local carrier frequency estimation submodule for the second frequency point receives the phase detection result for the second frequency point. The carrier phase tracking auxiliary quantity at the second frequency point is input to the two input terminals of the second dual-input port filter to generate the carrier frequency estimate at the second frequency point. ;

[0079] The first frequency local carrier signal generation module includes a first frequency local carrier phase estimation generation submodule and a first frequency local carrier signal generation submodule. The former updates the first numerically controlled oscillator using the first frequency carrier frequency estimate to generate the first frequency local carrier phase estimate. The latter uses this phase estimation to generate the first local carrier signal. The feedback is sent to the carrier stripping submodule of the phase detection module. The second frequency local carrier signal generation module has a similar structure to the first frequency module, generating the second local carrier signal. .

[0080] Cross-assisted joint carrier phase tracking is achieved through the dual-input port filtering modules at the first and second frequency points. The dual-input port filters inside share a digital register unit, making the entire joint tracking loop structurally compact and eliminating the divergence risk caused by the instability of individual filters / joint filters in conventional schemes.

[0081] Compared to Figure 3Compared to existing joint tracking devices, the device of this invention saves a joint filter and its associated adder, reducing the complexity of hardware implementation. Furthermore, by eliminating the pole at the origin present in the original structure, the joint tracking loop maintains globally bounded input and bounded output stability under any initial conditions. Even if the signal at one frequency is briefly interrupted or interfered with, the auxiliary information at another frequency can still smoothly help the unlocked loop reconverge through the shared register structure, preventing the filter output from growing indefinitely. This ensures continuous and reliable positioning of the receiver in complex environments.

[0082] In some embodiments of the present invention, the phase detection module includes:

[0083] The carrier stripping submodule is used to mix the first frequency digital intermediate frequency signal with the first local carrier signal to obtain the first frequency baseband signal; and to mix the second frequency digital intermediate frequency signal with the second local carrier signal to obtain the second frequency baseband signal.

[0084] The pseudocode stripping submodule is used to strip pseudocode from the baseband signal at the first frequency point to obtain the pseudocode stripped signal at the first frequency point; and to strip pseudocode from the baseband signal at the second frequency point to obtain the pseudocode stripped signal at the second frequency point.

[0085] The integration zeroing submodule is used to perform integration zeroing on the signal after stripping the pseudocode at the first frequency point to obtain the integration result related to the first frequency point; and to perform integration zeroing on the signal after stripping the pseudocode at the second frequency point to obtain the integration result related to the second frequency point.

[0086] The phase detection submodule is used to perform phase detection on the correlation integration result of the first frequency point to obtain the phase detection result of the first frequency point; and to perform phase detection on the correlation integration result of the second frequency point to obtain the phase detection result of the second frequency point.

[0087] Figure 4 This diagram schematically illustrates one embodiment of the dual-input port filter of the present invention. In the figure, input port 1 receives the signal. Input port 2 receives signals , Indicates a digital register unit, This is a time constant, typically equal to the correlation integration time during signal reception. (Signal) Transmission from input port 1 to output port and signals Transmitted from input port 2 to output port It needs to pass through two identical digital register units, both of which are second-order filters. In the schematic diagram, , , This represents the parameters of the second-order filter from input port 1 to output port. , , This represents the parameters of the second-order filter from input port 2 to the output port.

[0088] In some embodiments of the present invention, the first frequency point dual-input port filtering module includes:

[0089] The first frequency point auxiliary term generation submodule is used to multiply the second frequency point phase detection result by the first scaling factor to obtain the first frequency point carrier phase tracking auxiliary quantity.

[0090] The first frequency point local carrier frequency estimation submodule is used to receive the first frequency point phase detection result and the first frequency point carrier phase tracking auxiliary quantity, and input them to the first dual-input port filter respectively to generate the first frequency point carrier frequency estimate.

[0091] In some embodiments of the present invention, the second frequency point dual-input port filtering module includes:

[0092] The second frequency point auxiliary term generation submodule is used to multiply the first frequency point phase detection result by the second scaling factor to obtain the second frequency point carrier phase tracking auxiliary quantity.

[0093] The second frequency point local carrier frequency estimation submodule is used to receive the second frequency point phase detection result and the second frequency point carrier phase tracking auxiliary quantity, and input them to the second dual-input port filter respectively to generate the second frequency point carrier frequency estimate.

[0094] In some embodiments of the present invention, the first dual-input port filter or the second dual-input port filter, which is used to receive the first transfer function from the first input port to the output port for receiving the phase detection result of the local frequency point, and the second transfer function from the second input port to the output port for receiving the carrier phase tracking auxiliary quantity of the local frequency point, share a digital register unit in the hardware and software implementation.

[0095] In some embodiments of the present invention, the total number N of digital register units required to construct a dual-input port filter satisfies N=max(N1,N2), where N1 is the number of first digital register units required to construct the first transfer function, and N2 is the number of second digital register units required to construct the second transfer function.

[0096] The same principle applies to the first dual-input port filter and the second dual-input port filter.

[0097] In some embodiments of the present invention, the first frequency point local carrier signal generation module includes:

[0098] The first frequency point local carrier phase estimation generation submodule is used to update the first numerically controlled oscillator using the first frequency point carrier frequency estimate and generate the first frequency point local carrier phase estimate.

[0099] The first frequency point local carrier signal generation submodule is used to generate the first local carrier signal by using the phase estimation of the first frequency point local carrier.

[0100] In some embodiments of the present invention, the second frequency point local carrier signal generation module includes:

[0101] The second frequency point local carrier phase estimation generation submodule is used to update the second numerically controlled oscillator using the second frequency point carrier frequency estimate and generate the second frequency point local carrier phase estimate.

[0102] The second frequency local carrier signal generation submodule is used to generate the second local carrier signal by using the phase estimation of the second frequency local carrier.

[0103] According to one aspect of the present invention, an electronic device is provided, comprising: one or more processors, one or more memories, and one or more computer programs; wherein the processor is connected to the memory, and the one or more computer programs are stored in the memory, and when the electronic device is running, the processor executes the one or more computer programs stored in the memory to cause the electronic device to perform a cross-assisted dual-frequency signal carrier phase joint tracking method as described in any of the above technical solutions.

[0104] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

[0105] The memory can be an internal storage unit of the terminal device, such as a hard drive or RAM. Alternatively, it can be an external storage device, such as a plug-in hard drive, Smart Media Card (SMC), Secure Digital (SD) card, or Flash Card. Furthermore, the memory can include both internal and external storage units. The memory is used to store the computer program and other programs and data required by the terminal device. It can also be used to temporarily store data that has been output or will be output.

[0106] According to one aspect of the present invention, a computer-readable storage medium is provided for storing computer instructions, which, when executed by a processor, implement a cross-assisted dual-frequency signal carrier phase joint tracking method as described in any of the above technical solutions.

[0107] For example, computer-readable storage media can be read-only memory (ROM), random access memory (RAM), read-only optical disc (CD-ROM), magnetic tape, floppy disk, and optical data storage devices. They can be implemented using computer-executable program code, thus allowing them to be stored in a storage device for execution by a computing device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Therefore, this invention is not limited to any particular hardware and software combination.

[0108] This invention provides a cross-assisted dual-frequency signal carrier phase joint tracking method and apparatus. By cross-coupling the phase detection results of the first and second frequency points, carrier phase tracking auxiliary quantities are generated for each frequency point. A dual-input port filter is then used to jointly filter the phase detection results and auxiliary quantities for each frequency point. This architecture decomposes the independent joint filter function of traditional joint tracking schemes and integrates it into the filters of each frequency point, achieving effective fusion of dual-frequency signal information without the need for a separate joint filter.

[0109] In terms of stability, the dual-input port filter shares digital register units in its hardware and software implementation, allowing the signals from the two input ports to be processed in the same dynamic system. This eliminates the poles of the transfer function at the origin in the original architecture from the system model level, thereby eradicating the problem of individual filter output divergence in conventional joint tracking schemes and improving the global stability and robustness to transient disturbances of the joint tracking loop.

[0110] In terms of tracking performance, this invention maintains the advantages of joint tracking, such as improved carrier phase tracking accuracy and reduced carrier phase tracking threshold, while simplifying the complexity of the joint tracking architecture and reducing hardware resource overhead through the compact structure of shared registers. When the signal quality at a certain frequency temporarily degrades, auxiliary information from another frequency can smoothly support the continuous tracking of weak signal loops through cross-branching, avoiding loop lockout caused by divergence of individual filter outputs, thereby shortening the signal recovery time and ensuring the continuity of the receiver's positioning service in complex environments.

[0111] The above description is merely one embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A cross-assisted dual-frequency signal carrier phase joint tracking method, characterized in that, Includes the following steps: Step S1: Simultaneously receive a first frequency signal and a second frequency signal from the same satellite, and process the first frequency signal and the second frequency signal into a first frequency digital intermediate frequency signal and a second frequency digital intermediate frequency signal, respectively. Step S2: Perform carrier stripping, pseudocode stripping, integration zeroing and phase detection processing on the first frequency digital intermediate frequency signal and the second frequency digital intermediate frequency signal respectively to obtain the phase detection result of the first frequency point and the phase detection result of the second frequency point. Step S3: Multiply the first frequency point phase detection result by the first scaling factor to obtain the second frequency point carrier phase tracking auxiliary amount used to assist the second frequency point tracking; Multiply the phase detection result of the second frequency point by the second scaling factor to obtain the first frequency point carrier phase tracking auxiliary quantity used to assist the first frequency point tracking; Step S4: Input the first frequency point phase detection result and the first frequency point carrier phase tracking auxiliary quantity together into the first dual-input port filter to generate the first frequency point carrier frequency estimate; The phase detection result of the second frequency point and the carrier phase tracking auxiliary quantity of the second frequency point are input together into the second dual-input port filter to generate the carrier frequency estimate of the second frequency point. Step S5: Generate a first local carrier signal using the first frequency point carrier frequency estimate, the first local carrier signal being used to perform carrier stripping on the first frequency point digital intermediate frequency signal; generate a second local carrier signal using the second frequency point carrier frequency estimate, the second local carrier signal being used to perform carrier stripping on the second frequency point digital intermediate frequency signal.

2. The cross-assisted dual-frequency signal carrier phase joint tracking method according to claim 1, characterized in that, The first frequency signal and the second frequency signal are signals with different carrier frequencies transmitted by the same satellite.

3. The cross-assisted dual-frequency signal carrier phase joint tracking method according to claim 1, characterized in that, Step S2 specifically includes: Step S21: Mix the first frequency digital intermediate frequency signal with the first local carrier signal to remove the carrier and obtain the first frequency baseband signal; mix the second frequency digital intermediate frequency signal with the second local carrier signal to remove the carrier and obtain the second frequency baseband signal. Step S22: Perform pseudocode stripping on the first frequency baseband signal to obtain the pseudocode stripped signal at the first frequency; perform pseudocode stripping on the second frequency baseband signal to obtain the pseudocode stripped signal at the second frequency. Step S23: Perform integration and zeroing on the signal after stripping the pseudocode at the first frequency point to obtain the correlation integration result of the first frequency point; perform integration and zeroing on the signal after stripping the pseudocode at the second frequency point to obtain the correlation integration result of the second frequency point; Step S24: Perform phase detection on the correlation integration result of the first frequency point to obtain the phase detection result of the first frequency point; perform phase detection on the correlation integration result of the second frequency point to obtain the phase detection result of the second frequency point.

4. The cross-assisted dual-frequency signal carrier phase joint tracking method according to claim 1, characterized in that, Both the first scaling factor and the second scaling factor are real numbers greater than zero.

5. The cross-assisted dual-frequency signal carrier phase joint tracking method according to claim 1, characterized in that, In step S4, both the first dual-input port filter and the second dual-input port filter are filters with a first input port and a second input port; wherein, the first input port is used to input the phase detection result of the current frequency point, and the second input port is used to input the carrier phase tracking auxiliary quantity generated by the phase detection result of another frequency point to assist the tracking of the current frequency point; For the first dual-input port filter, its first input port to output port has a first transfer function H1(z), and its second input port to output port has a second transfer function H2(z); the implementation of the first transfer function H1(z) and the implementation of the second transfer function H2(z) share a digital register unit.

6. The cross-assisted dual-frequency signal carrier phase joint tracking method according to claim 5, characterized in that, For the second dual-input port filter, its first input port to output port has a third transfer function H3(z), and its second input port to output port has a fourth transfer function H4(z); the implementation of the third transfer function and the implementation of the fourth transfer function share a digital register unit.

7. The cross-assisted dual-frequency signal carrier phase joint tracking method according to claim 5 or 6, characterized in that, The total number of digital register units N required to construct a dual-input port filter satisfies N=max(N1,N2), where N1 is the number of first digital register units required to implement the first transfer function H1(z), and N2 is the number of second digital register units required to implement the second transfer function H2(z). The total number of digital register units M required to construct the second dual-input port filter satisfies M = max(M1,M2), where M1 is the number of third digital register units required to construct the third transfer function H3(z), and M2 is the number of fourth digital register units required to construct the fourth transfer function H4(z).

8. The cross-assisted dual-frequency signal carrier phase joint tracking method according to claim 1, characterized in that, Step S5 specifically includes: Step S51: Update the first numerically controlled oscillator using the first frequency point carrier frequency estimate to generate the first frequency point local carrier phase estimate; update the second numerically controlled oscillator using the second frequency point carrier frequency estimate to generate the second frequency point local carrier phase estimate. Step S52: Generate the first local carrier signal using the local carrier phase estimation at the first frequency point; generate the second local carrier signal using the local carrier phase estimation at the second frequency point.

9. A cross-assisted dual-frequency signal carrier phase joint tracking device, characterized in that, include: The receiver antenna is used to simultaneously receive signals from the first and second frequency points of the same satellite. The downconversion module is used to perform downconversion processing on the first frequency signal and the second frequency signal to generate a first frequency digital intermediate frequency signal and a second frequency digital intermediate frequency signal respectively. The phase detection module is used to perform carrier stripping, pseudocode stripping, integration zeroing and phase detection processing on the first frequency digital intermediate frequency signal and the second frequency digital intermediate frequency signal, respectively, to obtain and output the phase detection result of the first frequency and the phase detection result of the second frequency. The first frequency point dual-input port filtering module is used to receive the first frequency point phase detection result, and to receive the first frequency point carrier phase tracking auxiliary quantity obtained by multiplying the second frequency point phase detection result by the first scaling factor, and to generate the first frequency point carrier frequency estimate. The second frequency point dual-input port filtering module is used to receive the second frequency point phase detection result, and to receive the second frequency point carrier phase tracking auxiliary quantity obtained by multiplying the first frequency point phase detection result by the second scaling factor, and to generate the second frequency point carrier frequency estimate. The first frequency point local carrier signal generation module is used to generate a first local carrier signal based on the first frequency point carrier frequency estimate. The first local carrier signal is used to perform carrier stripping on the first frequency point digital intermediate frequency signal. The second frequency point local carrier signal generation module is used to generate a second local carrier signal based on the second frequency point carrier frequency estimate. The second local carrier signal is used to perform carrier stripping on the second frequency point digital intermediate frequency signal.

10. The cross-assisted dual-frequency signal carrier phase joint tracking device according to claim 9, characterized in that, The phase detection module includes: The carrier stripping submodule is used to mix the first frequency digital intermediate frequency signal with the first local carrier signal to obtain the first frequency baseband signal; and to mix the second frequency digital intermediate frequency signal with the second local carrier signal to obtain the second frequency baseband signal. The pseudocode stripping submodule is used to strip pseudocode from the baseband signal at the first frequency point to obtain the pseudocode stripped signal at the first frequency point; and to strip pseudocode from the baseband signal at the second frequency point to obtain the pseudocode stripped signal at the second frequency point. The integration zeroing submodule is used to perform integration zeroing on the signal after stripping the pseudocode at the first frequency point to obtain the integration result related to the first frequency point; and to perform integration zeroing on the signal after stripping the pseudocode at the second frequency point to obtain the integration result related to the second frequency point. The phase detection submodule is used to perform phase detection on the correlation integration result of the first frequency point to obtain the phase detection result of the first frequency point; and to perform phase detection on the correlation integration result of the second frequency point to obtain the phase detection result of the second frequency point.

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