Carrier half-cycle ambiguity elimination method, satellite signal resolving method and electronic equipment

Abstract

The invention discloses a carrier half-cycle ambiguity elimination method, a satellite signal resolving method and electronic equipment. The carrier half-cycle ambiguity elimination method comprises the following steps: acquiring observation values of satellite signals based on a DET tracking algorithm of a double estimator technology, wherein the observation values comprise a carrier observation value, a subcarrier observation value and a pseudo code observation value; determining a subcarrier phase estimation result according to the pseudo code observation value; judging whether subcarrier half-cycle ambiguity exists or not based on the subcarrier phase estimation result and the subcarrier observation value; and eliminating the half-cycle ambiguity of the carrier by adjusting the frequency control word of the subcarrier under the condition of determining that the half-cycle ambiguity of the subcarrier exists. According to the scheme, the semi-cycle ambiguity identification problem caused by a DET tracking mode is solved, the subcarrier semi-cycle ambiguity and the carrier semi-cycle ambiguity are further eliminated, and an accurate satellite signal observation value is provided for completing high-precision RTK calculation.

Description

TECHNICAL FIELD

[0001] The present application relates to, but is not limited to, the field of satellite positioning technology, in particular to a carrier half-cycle ambiguity resolution method, a satellite signal solution method and an electronic device. BACKGROUND

[0002] Global Navigation Satellite System (GNSS) can provide three-dimensional, all-weather, high-quality positioning, navigation and timing (PNT) services to global users, and is a very key positioning means in the transportation, communication, surveying and mapping and other industries. RTK technology (Real-Time Kinematic) is a global high-precision positioning technology, which can provide centimeter-level position accuracy through real-time data transmission and differential positioning technology. In recent years, with the rapid development of satellite navigation technology, RTK technology has been more and more widely used, and has achieved remarkable results in the fields of agriculture, surveying and mapping, aerospace, military and other fields. The carrier phase observation is a very important factor in RTK positioning technology, which can be understood by Figure 1 The carrier phase observation includes an integer part and a decimal part, the integer part is determined in the RTK solution, and the decimal part needs to be determined in the receiver tracking stage.

[0003] BPSK is a binary phase shift keying (Binary Phase Shift Keying) digital modulation method, which is widely used in various digital communication systems. Binary Offset Carrier (BOC) modulation is a new modulation technology gradually established with the development of navigation technology. BOC modulation technology is based on BPSK modulation multiplied by a subcarrier, which is represented in the frequency domain as moving the transmitted spread spectrum signal to both sides of the transmission frequency point, so that two types of signals can effectively share the same frequency band and do not interfere with each other. For high-order BOC signals, the DET (Dual Estimate) tracking method is generally used, and the autocorrelation function of high-order BOC signals has a multi-peak characteristic, which can cause the tracking to be easily locked to the side peak, causing ranging deviation and other problems, and the DET tracking method needs to increase a subcarrier tracking loop independent of the pseudocode loop, which can effectively solve the above problems. However, due to the half-cycle ambiguity of the subcarrier tracking, the carrier phase observation has half-cycle ambiguity. The traditional BPSK signal can determine the half-cycle ambiguity through the text polarity, but in the DET tracking method, the ambiguity of the subcarrier is increased, so even if the text polarity is determined, the subcarrier polarity cannot be determined. SUMMARY

[0004] The embodiment of the present application provides a carrier half cycle ambiguity elimination method, a satellite signal solution method and an electronic device, whether there is half cycle ambiguity is judged according to the time relationship of pseudo code observation value and subcarrier observation value, the half cycle ambiguity identification problem caused by the DET tracking mode is solved, and the subcarrier half cycle ambiguity and the carrier half cycle ambiguity are further eliminated, accurate satellite signal observation values are provided for completing high-precision RTK solution.

[0005] The embodiment of the present application provides a carrier half cycle ambiguity elimination method, which comprises: The observation value of the satellite signal is acquired based on a double estimator technology DET tracking algorithm, and the observation value comprises a carrier observation value, a subcarrier observation value and a pseudo code observation value; The subcarrier phase estimation result is determined according to the pseudo code observation value; Whether there is subcarrier half cycle ambiguity is judged based on the subcarrier phase estimation result and the subcarrier observation value; In the case that it is determined that there is subcarrier half cycle ambiguity, the carrier half cycle ambiguity is eliminated by adjusting the subcarrier frequency control word.

[0006] The embodiment of the present application further provides a satellite signal solution method, which comprises: Based on the received satellite signal, the carrier half cycle ambiguity is eliminated according to the carrier half cycle ambiguity elimination method as described in any embodiment of the present application; The real-time dynamic difference technology RTK solution is performed according to the updated observation value after the half cycle ambiguity elimination is completed.

[0007] The embodiment of the present application provides an electronic device, which comprises one or more processors, a storage device for storing one or more programs, When the one or more programs are executed by the one or more processors, the one or more processors implement the carrier half cycle ambiguity elimination method as described in any embodiment of the present application, or the one or more processors implement the satellite signal solution method as described in any embodiment of the present application.

[0008] Other features and advantages of the present application will be described in the following description, and some will become apparent from the description, or will be learned from the practice of the present application. Other advantages of the present application can be achieved and obtained through the schemes described in the specification and the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0009] The accompanying drawings are used to provide an understanding of the technical scheme of the present application, and constitute a part of the specification, and are used to explain the technical scheme of the present application together with the embodiments of the present application, and do not constitute a limitation on the technical scheme of the present application.

[0010] Figure 1Carrier phase observation principle in some implementable schemes Figure 2 Modulation flowchart of BOC signal in some implementable schemes Figure 3 DET tracking algorithm structure block diagram provided by the embodiment of the present disclosure Figure 4 Carrier half-cycle ambiguity elimination method flowchart provided by the embodiment of the present disclosure Figure 5 Satellite signal solution method flowchart provided by the embodiment of the present disclosure Figure 6 Another satellite signal solution method flowchart provided by the embodiment of the present disclosure DETAILED DESCRIPTION

[0011] The present application describes a plurality of embodiments, but the description is exemplary rather than limiting, and it is obvious to those of ordinary skill in the art that there can be more embodiments and implementation schemes within the scope of the embodiments described in the present application. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are possible. Unless specifically limited, any feature or element of any embodiment can be used with any other feature or element of any other embodiment, or can replace any other feature or element of any other embodiment.

[0012] The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in the present application can also be combined with any conventional features or elements to form a unique inventive scheme. Any feature or element of any embodiment can also be combined with features or elements from other inventive schemes to form another unique inventive scheme. Therefore, it should be understood that any feature shown and / or discussed in the present application can be implemented alone or in any appropriate combination. Therefore, the embodiments are not limited other than according to the limitations made according to the appended claims and their equivalent replacements. In addition, various modifications and changes can be made within the scope of protection of the appended claims.

[0013] Moreover, in describing representative embodiments, the specification can have presented the method and / or process as a particular sequence of steps. However, to the extent that the method or process depends on the particular order of steps, this description should not be construed as limiting since other steps can be performed in other sequences and / or omitted from the method or process. Therefore, the particular order of steps presented in the specification should not be construed as a limitation on the claims. Furthermore, the claims should not be limited to the steps of the method and / or process in the order presented in the specification. Other steps can be added to the method and / or process and / or the order of steps can be changed without departing from the scope of the claims.

[0014] The existing carrier phase ambiguity fixing method is based on the premise that the ambiguity is an integer. If the ambiguity is not an integer, the existing method cannot be used to solve the integer ambiguity, and high-precision RTK results cannot be obtained. Generally, the receiver uses a Costas loop that is not sensitive to 180° phase (half-cycle) jumps to track the carrier of the GNSS signal, so when the GNSS signal is just tracked, the carrier phase output by the Costas loop has a half-cycle uncertainty. The receiver generally needs to complete the polarity judgment and solve the synchronization header of the GNSS signal to eliminate the half-cycle uncertainty and obtain normal carrier phase observations.

[0015] For BOC signals, the DET tracking algorithm is generally used, which requires the addition of a subcarrier tracking loop independent of the code loop, but due to the half-cycle ambiguity of the subcarrier tracking, the carrier phase observation value also has a half-cycle ambiguity. That is, in the DET tracking algorithm, due to the introduction of the subcarrier loop tracking, there is a half-cycle uncertainty, and even if the message polarity is determined, the half-cycle ambiguity cannot be determined.

[0016] Current RTK algorithms can solve integer ambiguity but cannot determine half-cycle ambiguity, while traditional BPSK signals can determine half-cycle ambiguity through message polarity. However, these methods cannot solve the half-cycle ambiguity caused by the DET tracking method. The present application provides a carrier half-cycle ambiguity elimination scheme to solve the half-cycle ambiguity problem caused by the DET tracking algorithm, ensure the accuracy of the RTK solution, and improve the performance of the receiver.

[0017] The BOC signal modulation method is as shown in Figure 2 The BOC signal received by the receiver can be represented as: ; Wherein, is the signal amplitude, is the intermediate frequency, is the Doppler frequency, is the initial carrier phase, For subcarrier components, For pseudo-code components, For message bits.

[0018] In some exemplary embodiments, the BOC signal tracking scheme employing the DET tracking algorithm, such as... Figure 3 As shown, the subcarrier is considered a separate one-dimensional signal component, holding the same status as the pseudo-code component and carrier component in the BOC signal. A subcarrier tracking loop (SLL, or subcarrier loop for short) is added to synchronize the subcarrier component in the received signal, similar to a carrier tracking loop (or carrier loop for short) and a pseudo-code tracking loop (or pseudo-code loop for short). The receiver first performs carrier stripping, then subcarrier stripping, and finally despreads and removes the pseudo-random code to obtain the navigation message data. Here, P / E / L represents the instantaneous branch, the leading branch, and the lagging branch; DLL is the delay-locked loop; SLL is the subcarrier-locked loop; and FLL / PLL is the frequency-locked loop / phase-locked loop. The integral results for branch I are given.

[0019] Ignoring the influence of navigation message data and amplitude, after relevant calculations, we can obtain ; in, The correlation integral value of the instantaneous branch of the subcarrier of the I branch and the instantaneous branch of the pseudo-random code. The signal amplitude, For the relevant integration time, For carrier phase difference, , For subcarrier components, , This is a pseudocode component.

[0020] In some exemplary embodiments, the normalized autocorrelation function graph of the subcarrier is as follows: Figure 4 As shown, due to the periodicity of the subcarrier, the correlation peak of the subcarrier loop is easily locked at ±1, resulting in half-cycle ambiguity in the subcarrier. The above equation shows that the carrier also suffers from half-cycle ambiguity. Therefore, the half-cycle ambiguity of the subcarrier can be eliminated, and consequently, the half-cycle ambiguity of the carrier can be eliminated.

[0021] This application provides a carrier half-cycle ambiguity elimination method, such as... Figure 4 As shown, it includes: Step 410: Obtain satellite signal observations based on the DET tracking algorithm. The observations include: carrier observations, subcarrier observations, and pseudocode observations. Step 420, determining a sub-carrier phase estimation result according to the pseudo-code observation value; Step 430, judging whether there is a sub-carrier half-cycle ambiguity based on the sub-carrier phase estimation result and the sub-carrier observation value; Step 440, in the case of determining that there is a sub-carrier half-cycle ambiguity, eliminating the carrier half-cycle ambiguity by adjusting the sub-carrier frequency control word.

[0022] In some example embodiments, the carrier observation value includes: carrier Doppler, also known as Doppler shift; or, further includes: carrier phase. The sub-carrier observation value includes: integer cycle count SubCodeCnt of the sub-carrier observation value and decimal phase SubCodeNCO of the sub-carrier observation value. Wherein, SubCodeNCO is the decimal phase value read from the phase register of the numerically controlled oscillator (NCO) in the sub-carrier tracking loop. The pseudo-code observation value includes: chip count CodeCnt of the pseudo-code observation value and decimal chip phase CodeNCO of the pseudo-code observation value. Optionally, other data items can also be included. Wherein, CodeNCO is the decimal phase value read from the phase register of the NCO in the pseudo-code tracking loop.

[0023] In some example embodiments, step 420 includes: determining a sub-carrier phase estimation result according to the pseudo-code observation value; and judging whether there is a half-cycle ambiguity based on the sub-carrier phase estimation result and the sub-carrier observation value.

[0024] It can be known that there is a fixed, known timing alignment relationship between the chip jump (for example, jump from 0 to 1 or from 1 to 0) of the pseudo-code in the satellite signal and the zero-crossing point (or phase jump point) of the sub-carrier. The present application scheme utilizes this characteristic to judge whether there is a half-cycle ambiguity.

[0025] Since the pseudo-code phase and the sub-carrier phase are aligned when the signal is transmitted, the sub-carrier phase estimation can be performed according to the pseudo-code observation value, and the estimation result is compared with the actual sub-carrier observation value to judge whether there is a half-cycle ambiguity.

[0026] Wherein, the sub-carrier phase estimation result is determined according to the tracking result of the pseudo-code loop by the following method: ; Wherein, is the sub-carrier phase estimation result calculated according to the pseudo-code, is the sub-carrier chip rate, is the Doppler frequency, is the carrier frequency, is the pseudo-code chip rate, a chip count for a pseudo-code observation value, a fractional chip phase for a pseudo-code observation value.

[0027] In some example embodiments, a non-negative difference between the fractional part of the subcarrier phase estimation result and the fractional part of the subcarrier observation value is calculated as follows: ; wherein N is a bit width of a numerically controlled oscillator (NCO) in a subcarrier tracking loop; a fractional part of the subcarrier phase estimation result, a fractional part of the subcarrier observation value; in the case that the non-negative difference is greater than or equal to 0.5, it is determined that there is half-cycle ambiguity; and in the case that the non-negative difference is less than 0.5, it is determined that there is no half-cycle ambiguity.

[0028] The bit width N of the NCO refers to a bit width of a phase accumulator and a bit width of a register in the NCO in which a phase value is stored, and the bit width determines a frequency resolution of the NCO. For example, the bit width of the NCO is 16 bits, and N = 16; the bit width can also be 12, 32 or other values, which can be set according to a corresponding chip of a receiver.

[0029] In some example embodiments, m is an integer multiple of n.

[0030] wherein the fractional part of the subcarrier phase estimation result is determined according to the following method: ; wherein round is a rounding operation, is a subcarrier chip period.

[0031] In some example embodiments, the satellite signal is a BOC modulated signal, also referred to as a BOC signal, which is generally represented as BOC (f s, f c ), wherein f s = m x f 1 (reference frequency 1.023) and f c = n x f 1 (reference frequency 1.023), and for the sake of simplicity, is generally written in the form of BOC (m, n). m represents that a subcarrier frequency is m times of a reference frequency 1.023 MHz, and n represents that a spreading code rate is n times of the reference frequency 1.023 MHz. m is a subcarrier modulation coefficient, also referred to as a subcarrier frequency factor; and n is a spreading code rate coefficient, also referred to as a pseudo-code rate factor. Alternatively, the satellite signal can also be a derived BOC modulated signal.

[0032] ​For example, taking BOC(m, n) or the derived BOC modulation signal as an example, the determination of the half-cycle ambiguity is related to whether m / n is divisible. Taking BOC(14, 2) as an example, 14 / 2 = 7 is an integer, and whether there is a half-cycle ambiguity of the subcarrier is determined according to the following manner: ; In the case of , it is determined that there is a half-cycle ambiguity of the subcarrier; otherwise, it is determined that there is no half-cycle ambiguity of the subcarrier For example, for 14 signal channels of the receiver, the results of whether there is a half-cycle ambiguity of the subcarrier according to the above method are shown in Table 1 as follows: Table 1 - Relationship between subcarrier phase estimation result and actual observation value, and determination result of half-cycle ambiguity

[0033] Wherein, mark 1 indicates that there is a half-cycle ambiguity of the subcarrier, and 0 indicates that there is no half-cycle ambiguity of the subcarrier.

[0034] It can be known that the carrier half-cycle ambiguity elimination method and the satellite signal solving method provided by the embodiments of the present application can be applied to various satellite positioning systems, such as the Beidou satellite positioning system, the GPS satellite positioning system, the Galileo satellite positioning system, etc.

[0035] Therefore, the identification of whether there is a half-cycle ambiguity of the subcarrier in the DET tracking algorithm is realized. Further, for the signal channel with the half-cycle ambiguity of the subcarrier, the carrier half-cycle ambiguity is eliminated by adjusting the subcarrier frequency control word, including: adjusting the subcarrier frequency control word to align the local subcarrier to the integer cycle, so as to eliminate the half-cycle ambiguity of the subcarrier, and further eliminate the carrier half-cycle ambiguity.

[0036] That is, if it is detected that there is a half-cycle ambiguity of the subcarrier, that is, the phase difference is π, the local subcarrier phase needs to be "chased" or "delayed" by adjusting the subcarrier frequency control word K, and finally the deviation of π is eliminated: if the local subcarrier phase lags behind the received signal by π, K is increased, the local phase accumulation is faster, and the phase difference is gradually reduced to 0; if the local subcarrier phase leads the received signal by π, K is reduced, the local phase accumulation is slower, until the phase difference converges to 0, so as to eliminate the half-cycle ambiguity of the subcarrier, and further eliminate the carrier half-cycle ambiguity.

[0037] In some example embodiments, the adjusting the subcarrier frequency control word to align the local subcarrier to the integer cycle includes: According to the current correlation interval CorInterval of the subcarrier correlator, the subcarrier frequency control word adjustment value JumpCount = 1 / CorInterval is calculated. At the subcarrier tracking loop update interval, the subcarrier correlator controls the NCO in the subcarrier tracking loop to perform JumpCount times of overflow to achieve the integer cycle alignment.

[0038] For example, the correlation interval CorInterval = 1 / 4, and the subcarrier frequency control word adjustment value JumpCount = 1 / (1 / 4) = 4 is calculated. At the subcarrier tracking loop update interval, the subcarrier correlator controls the NCO in the subcarrier tracking loop to perform 4 times of overflow. Thus, the alignment is achieved, and the half-cycle ambiguity is eliminated.

[0039] When updating the subcarrier and carrier observations at the next observation time, it can be determined whether the half-cycle ambiguity has been eliminated. For example, by performing the above-mentioned adjustment of the subcarrier frequency control word, the result of determining whether there is a subcarrier half-cycle ambiguity at the next observation time according to the foregoing method is shown in Table 2 as follows: Table 2 - Relationship between subcarrier phase estimation results after elimination and actual observations, and determination results of subcarrier half-cycle ambiguity

[0040] It can be seen that the half-cycle ambiguity has been eliminated for channels 5, 7, 8, 10, 12, 13, and 14.

[0041] Based on the updated observations after eliminating the half-cycle ambiguity, RTK calculation can be further performed to determine the positioning result.

[0042] In some example embodiments, step 410 includes: capturing the satellite signal, and setting the pseudo-code tracking loop to the DET tracking mode. Through continuous discrimination and filtering by the carrier, pseudo-code, and subcarrier tracking loops running in parallel, the respective frequency control words are dynamically updated, and the corresponding observations in the satellite signal are extracted.

[0043] In some example embodiments, step 410 further includes: capturing the satellite signal, determining whether the DET follow-up algorithm is currently used, and in the case of determining that it is used, setting the pseudo-code tracking loop to the DET tracking mode; The determination of whether the DET follow-up algorithm is currently used includes: determining according to at least one of the following determination bases: the receiver carrier type, the satellite signal strength, the application scenario, and the positioning application setting.

[0044] The receiver carrier type includes: a high-dynamic, high-speed or high-acceleration mobile carrier, a low-dynamic, static or low-speed carrier, etc.; the application scenario includes: an open scene, a city canyon, an indoor scene, a tree shade, etc.; and the positioning application setting includes: maintaining high-dynamic positioning tracking continuity, a balanced type, etc. The specific judgment standard is flexibly determined according to the needs, and is not limited to a specific aspect. It can be understood that, in the case of meeting the DET tracking mode setting condition, the corresponding setting is performed, and then the observation value is obtained according to the scheme provided in the embodiments of the present disclosure, it is judged whether there is a subcarrier half-cycle ambiguity, and half-cycle ambiguity elimination is performed. If the DET tracking mode setting condition is not met, no setting is performed, and other ways are used for satellite signal processing and RTK calculation, and the related aspects are not discussed in detail here.

[0045] After successfully capturing the satellite signal, the receiver sets the tracking mode of the designated channel to the DET tracking mode. In this mode, the system initializes two or more estimators in parallel for the carrier tracking loop, the code tracking loop and the subcarrier tracking loop. The estimator continuously runs in a high-frequency iteration period (for example, 1 kHz), and its core is a prediction-correction closed loop; that is, the carrier tracking loop, the code tracking loop and the subcarrier tracking loop continuously run in parallel, respectively performing: discrimination, filtering, and dynamically updating the frequency control word. After the tracking loop is stably locked, the high-precision observation value is directly extracted from the state vector of the selected optimal estimator.

[0046] The embodiments of the present disclosure also provide a satellite signal calculation method, as shown in Figure 5 The embodiments of the present disclosure also provide a satellite signal calculation method, as shown in Step 510: based on the received satellite signal, the carrier half-cycle ambiguity is eliminated according to the method as described in any of the embodiments of the present disclosure; Step 520: based on the updated observation value after the half-cycle ambiguity elimination is completed, real-time dynamic differential technology RTK calculation is performed.

[0047] In step 510, the updated observation value is obtained, and it is determined whether the carrier half-cycle ambiguity has been eliminated according to the latest observation value. After it is determined that the carrier half-cycle ambiguity has been eliminated, the RTK calculation is performed according to the latest observation value to obtain a corresponding result. In some exemplary embodiments, the result includes: positioning information, for example, coordinate data; or further includes: one or more of the calculation state, the quality index, the baseline vector and the observation value residual. The specific calculation process is not discussed in detail here.

[0048] The embodiments of the present disclosure also provide a satellite signal calculation method, as shown in Figure 6 The embodiments of the present disclosure also provide a satellite signal calculation method, as shown in Step 610: capturing a satellite signal; Step 620: setting a DET tracking mode; Step 630, obtaining an observation value; Step 640, judging whether there is a half-cycle ambiguity of subcarrier; if yes, performing step 650, and if no, performing step 660; Step 650, eliminating the half-cycle ambiguity of carrier, and updating the observation value; Step 660, performing RTK resolving.

[0049] The embodiments of the present disclosure further provide an electronic device, comprising: one or more processors; a storage device configured to store one or more programs, When the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the satellite signal resolving method according to any one of the embodiments of the present disclosure.

[0050] In some exemplary embodiments, the electronic device is a satellite positioning receiver, which comprises: a smart phone, a vehicle-mounted device, etc.

[0051] The half-cycle ambiguity elimination scheme provided by the embodiments of the present disclosure determines the ambiguity of subcarrier tracking through the time relationship between the pseudo code and the subcarrier, and then aligns the local subcarrier to the whole cycle by adjusting the frequency control word of the subcarrier, so as to eliminate the half-cycle ambiguity of the subcarrier and further eliminate the half-cycle ambiguity of the carrier, thereby solving the half-cycle ambiguity problem caused by the DET tracking mode.

[0052] Those skilled in the art can understand that all or some of the steps in the method disclosed above, the functional modules / units in the system and the device can be implemented as software, firmware, hardware and appropriate combinations thereof. In the hardware implementation, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component can have multiple functions, or one function or step can be performed by several physical components in cooperation. Some or all of the components can be implemented as software executed by a processor, such as a digital signal processor or a microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer readable medium, which can include computer storage media (or non-transitory media) and communication media (or transitory media). As known to those skilled in the art, the term "computer storage media" includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, as known to those skilled in the art, communication media typically includes computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism, and can include any information delivery medium.

[0053] Although the embodiments of the present application have been shown and described above, it is to be understood that the above-described embodiments are exemplary, and cannot be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A method for eliminating half-cycle ambiguity of a carrier wave, characterized in that, include: The DET tracking algorithm, based on dual estimator technology, acquires observations of satellite signals, including carrier observations, subcarrier observations, and pseudocode observations. Based on the pseudocode observations, the subcarrier phase estimation result is determined; Based on the subcarrier phase estimation results and the subcarrier observation values, determine whether there is subcarrier half-cycle ambiguity; If the existence of subcarrier half-cycle ambiguity is confirmed, the carrier half-cycle ambiguity is eliminated by adjusting the subcarrier frequency control word.

2. The method according to claim 1, characterized in that, The step of determining the subcarrier phase estimation result based on the pseudocode observations includes: Based on the pseudocode observations, the subcarrier phase estimation result is determined using the following method: ； in, The subcarrier phase estimation result calculated based on the pseudocode. For subcarrier chip rate, For Doppler frequency, For carrier frequency, For pseudo-code chip rate, For the chip count of pseudocode observations, The phase of the small digital chip is the pseudocode observation value.

3. The method according to claim 1, characterized in that, The step of determining whether there is subcarrier half-cycle ambiguity based on the subcarrier phase estimation result and the subcarrier observation value includes: exist In this case, the existence of subcarrier half-cycle ambiguity is determined; In this case, it is determined that there is no subcarrier half-cycle ambiguity; ； Where N is the bit width of the numerically controlled oscillator NCO in the subcarrier tracking loop. The fractional part of the subcarrier phase estimation result. This refers to the fractional part of the subcarrier observation.

4. The method according to claim 3, characterized in that, The fractional part of the subcarrier phase estimation result Determined using the following method: ； in, The result is the subcarrier phase estimation. round For the floor operation, This is the subcarrier chip period.

5. The method according to any one of claims 1-3, characterized in that, The DET tracking algorithm based on dual estimator technology acquires satellite signal observations, including: Capture satellite signals and set the pseudocode tracking loop to DET tracking mode; The carrier, pseudocode, and subcarrier tracking loops operate in parallel to perform continuous identification and filtering, dynamically update their respective frequency control words, and extract the corresponding observation values ​​from the satellite signal.

6. The method according to claim 5, characterized in that, The process of capturing satellite signals and setting the pseudocode tracking loop to DET tracking mode includes: Capture satellite signals, determine whether the DET tracking algorithm is currently in use, and if it is determined to be in use, set the pseudocode tracking loop to DET tracking mode; The determination of whether the DET following algorithm is currently being used includes: making a judgment based on at least one of the following criteria: Receiver carrier type, satellite signal strength, application scenario, and positioning application settings.

7. The method according to any one of claims 1-3, characterized in that, The method of eliminating carrier half-cycle ambiguity by adjusting the subcarrier frequency control word includes: By adjusting the subcarrier frequency control word to align the local subcarrier to an integer cycle, the subcarrier half-cycle ambiguity is eliminated, thereby eliminating the carrier half-cycle ambiguity.

8. The method according to claim 7, characterized in that, The step of aligning the local subcarrier to an integer cycle by adjusting the subcarrier frequency control word includes: Based on the current correlation interval CorInterval of the subcarrier correlator, calculate the subcarrier frequency control word adjustment value JumpCount = 1 / CorInterval; During the subcarrier tracking loop update interval, the subcarrier correlator controls the numerically controlled oscillator (NCO) in the subcarrier tracking loop to perform JumpCount overflows to achieve integer alignment.

9. A satellite signal processing method, characterized in that, include: Based on the received satellite signals, the carrier half-cycle ambiguity is eliminated according to the method described in any one of claims 1-8; Based on the updated observations after half-cycle ambiguity elimination, real-time dynamic difference (RTK) solution is performed.

10. An electronic device, characterized in that, include: One or more processors; Storage device for storing one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the carrier half-cycle ambiguity elimination method as described in any one of claims 1-8; or, the one or more processors implement the satellite signal processing method as described in claim 9.

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