A Method and System for Monitoring GPS P(Y) Signal Power Enhancement Based on Civil Signal Tracking

Abstract

This invention relates to a method and system for monitoring and enhancing the power of GPS P(Y) signals based on civilian signal tracking. The method employs a carrier tracking loop to stably track civilian satellite navigation signals, generating a local carrier with the same frequency and phase as the GPS satellite navigation digital signal. The GPS satellite navigation digital signal is then orthogonally mixed with the local carrier to output the in-phase branch signal u. I (n) and the orthogonal branch signal u Q (n); the in-phase branch signal u I (n), Orthogonal branch signal u Q (n) Perform low-pass filtering and incoherent integration respectively to obtain the average power P of the baseband signal in the in-phase branch. IB Average power P of baseband signal in orthogonal branch QB The average power P of the baseband signal in the same phase branch IB Average power P of baseband signal in orthogonal branch QB The power enhancement state of the current P(Y) signal is determined by comparing it with the weak-state power threshold of the in-phase branch, the strong-state power threshold of the in-phase branch, the strong-state power threshold of the quadrature branch, and the weak-state power threshold of the quadrature branch.

Description

Technical Field

[0001] This invention relates to a method and system for monitoring enhanced GPS P(Y) signal power based on civilian signal tracking, belonging to the field of satellite navigation signal monitoring technology. Background Technology

[0002] GPS P(Y) signals are traditional, encrypted satellite navigation signals broadcast in the L1 and L2 frequency bands. To ensure receivers can continuously use P(Y) signals for positioning and navigation in harsh electromagnetic environments and disputed areas, GPS satellites enhance the P(Y) signal power in designated areas at specified times. Without knowing the encrypted P(Y) code, conventional signal reception methods cannot be used for P(Y) signal measurement and power monitoring.

[0003] To meet the high-precision positioning needs of users in geodesy, engineering construction, and transportation, receiver manufacturers have developed codeless and semi-codeless reception technologies, enabling L2P(Y) signal carrier phase measurement. See documents such as "Optimum Semi-codeless Carrier Phase Tracking of L2" (author: KTWoo, The 12th International Technical Meeting of the Satellite Division of the Institute of Navigation, September 14-17, 1999). Codeless and semi-codeless reception technologies can also be used to estimate the carrier-to-noise ratio (C / N0) of the P(Y) signal. The estimated C / N0 value of the P(Y) signal can be used to determine changes in P(Y) signal power. See documents such as "A GPS P(Y) Signal Power Enhancement Monitoring Method" (inventors: Yang Jianlei et al., application number: CN202110612066.6) and "GPS P(Y) Code Power Enhancement Monitoring Analysis" (authors: Li Wenxuan et al., Journal of Beijing University of Aeronautics and Astronautics, March 2022). The 2019 Federal Radionavigation Plan states that the U.S. government is committed to maintaining the existing L1P(Y) and L2P(Y) signal characteristics that allow for uncoded and semi-uncoded reception until 2029; noting that L2C signals will have terrestrial control capabilities in 2023, it recommends that civilian users begin the transition from uncoded and semi-uncoded receivers to modern civilian signal receivers. This demonstrates that uncoded and semi-uncoded reception technologies are not a sustainable solution for monitoring and enhancing P(Y) signal power.

[0004] Using a large-aperture, high-gain antenna, weak GPS signals can be boosted above the noise floor, thereby estimating the encrypted pseudocode sequence and the power ratio of each signal, ultimately achieving P(Y) signal power enhancement monitoring. See the following documents for details: "GPS BIIF-1 Satellite L1 Frequency QPSK VS CASM Signal Quality Assessment" (authors: Kang Li et al., Journal of Astronautics, Vol. 40, No. 1, January 2019), "Flex Power on GPS Block IIR-M and IIF" (authors: P. Steigenberger et al., GPSSolutions, 23(8), 2019), and "GPS P(Y) Code Power Enhancement Monitoring Analysis" (authors: Li Wenxuan et al., Journal of Beijing University of Aeronautics and Astronautics, online version, March 2022). The large-aperture, high-gain antennas used typically require tens of meters in diameter, resulting in high manufacturing and maintenance costs, fixed locations, and difficulty in transportation, limiting their use to fixed-point monitoring of P(Y) signal power enhancement. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a method and system for monitoring the power enhancement of GPS P(Y) signals based on civilian signal tracking. This method and system achieves real-time and highly sensitive monitoring of the power enhancement of encrypted GPS P(Y) signals without relying on the P(Y) signal characteristics required for uncoded and semi-uncoded reception or without using a large-aperture high-gain antenna.

[0006] The solution of this invention is: a GPS P(Y) signal power enhancement and monitoring method based on civilian signal tracking, which includes the following steps:

[0007] S1. After bandpass filtering, down-conversion, amplification, and analog-to-digital conversion of the GPS satellite navigation signal received by the L-band antenna, a GPS satellite navigation digital signal is obtained; the GPS satellite navigation digital signal is a radio frequency or intermediate frequency sampled signal.

[0008] S2. A carrier tracking loop is used to stably track the civilian satellite navigation signal, generating a local carrier with the same frequency and phase as the GPS satellite navigation digital signal. The GPS satellite navigation digital signal and the local carrier are orthogonally mixed, and the in-phase branch signal u is output. I (n) and the orthogonal branch signal u Q (n); The civilian satellite navigation signal is an L1C / A signal or an L2C signal;

[0009] S3, transfer the in-phase branch signal u I (n), Orthogonal branch signal u Q (n) Perform low-pass filtering and incoherent integration respectively to obtain the average power P of the baseband signal in the in-phase branch. IB Average power P of baseband signal in orthogonal branchesQB ;

[0010] S4. Calculate the weak-state power threshold of the in-phase branch. Strong-state power threshold of in-phase branch Weak-state power threshold of orthogonal branches Strong-state power threshold of orthogonal branches

[0011] S5. When the current P(Y) signal is not boosted, the average power P of the baseband signal in the same phase branch will be increased. IB Weak-state power threshold of the in-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Strong-state power threshold of orthogonal branches The comparison is performed to determine whether the current P(Y) signal has switched to a power enhancement state.

[0012] S6. When the current P(Y) signal has been enhanced, the average power P of the baseband signal in the same phase branch will be increased. IB Strong-state power threshold of the same-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Weak-state power threshold with orthogonal branches The comparison is performed, and the result is used to determine whether the current P(Y) signal has switched to a non-power-boosted state.

[0013] Preferably, in step S5, when the following formula is satisfied, the current P(Y) signal is determined to be in a power enhancement state; otherwise, the current P(Y) signal is determined to be in a non-power enhancement state:

[0014]

[0015] Preferably, in step S6, when the following formula is satisfied, the current P(Y) signal is determined to be in a non-power enhancement state; otherwise, the current P(Y) signal is determined to be in a power enhancement state:

[0016]

[0017] Preferably, the weak-state power threshold of the in-phase branch Weak-state power threshold of orthogonal branches The following formula is used to calculate:

[0018]

[0019] Among them, Th w,Id P is the reference value for the weak-state branch power threshold. w (i) represents the average power sample of the weak-state branch, where i is the sample number and N is the average power sample index. PThe number of samples for average power.

[0020] Preferably, the strong-state power threshold of the in-phase branch Strong-state power threshold of orthogonal branches It is calculated using the following formula:

[0021]

[0022] Among them, Th s,Id P is the reference value for the strong-state branch power threshold. s (j) represents the average power sample of the strong-state branch, where j is the sample number and N is the average power sample index. P The number of samples for average power.

[0023] Preferably, given the target false alarm probability Pr FaG The weak-state branch power threshold reference value Th w,Id The following conditions must be met:

[0024]

[0025] Where, N w is the number of sampling points included in the incoherent integral of the weak-state branch; x represents the average power random variable;

[0026] Given the target detection probability Pr DeG The weak-state branch power threshold reference value Th w,Id satisfy:

[0027]

[0028] in The following formula is used to derive:

[0029]

[0030] in, The average power of the navigation signal contained in the weak-state branch. The average power of the navigation signal increases after the branch transitions from a weak state to a strong state. This represents the power of the noise contained in the weak-state branch.

[0031] Preferably, given the target false alarm probability Pr FaG Strong-state branch power threshold reference value Th s,Id satisfy:

[0032]

[0033] Where, N s Let x be the number of sampling points included in the incoherent integral of the strong-state branch, and let x represent the average power random variable. The following formula is used to derive:

[0034]

[0035] in, The average power of the navigation signal contained in the strong-state branch. The average power of the navigation signal decreases after the branch transitions from a strong state to a weak state. The power of the noise contained in the strong-state branch;

[0036] Given the target detection probability Pr DeG Strong-state branch power threshold reference value Th s,Id Satisfy the following formula:

[0037]

[0038] Another technical solution of the present invention is: a GPS P(Y) signal power enhancement monitoring device based on civilian signal carrier tracking, the device including an L-band antenna, a radio frequency front-end processing module, a civilian signal carrier tracking loop, a dual-branch power decision module, an in-phase branch average power calculation module, an orthogonal branch average power calculation module, an in-phase branch threshold generation module, and an orthogonal branch threshold generation module.

[0039] The L-band antenna receives the GPS satellite navigation signals to be observed and sends them to the radio frequency front-end processing module.

[0040] The radio frequency front-end processing module performs bandpass filtering, down-conversion, amplification, and analog-to-digital conversion on the GPS satellite navigation signal received by the L-band antenna to obtain a GPS satellite navigation digital signal, which is then sent to the carrier tracking loop; the GPS satellite navigation digital signal is a radio frequency or intermediate frequency sampling signal.

[0041] The civilian signal carrier tracking loop is used to stably track civilian satellite navigation signals, generate a local carrier with the same frequency and phase as the GPS satellite navigation digital signal, and output the in-phase branch signal u after orthogonal mixing of the GPS satellite navigation digital signal and the local carrier. I (n) and the orthogonal branch signal u Q (n); The civilian satellite navigation signal is an L1C / A signal or an L2C signal;

[0042] The in-phase branch average power calculation module calculates the in-phase branch signal u. I (n) Perform low-pass filtering and incoherent integration to obtain the average power P of the baseband signal in the in-phase branch. IB ;

[0043] The orthogonal branch average power calculation module calculates the orthogonal branch signal u. Q (n) Perform low-pass filtering and incoherent integration to obtain the average power P of the baseband signal in the orthogonal branch. QB;

[0044] The in-phase branch threshold generation module is used to calculate the weak-state power threshold of in-phase branches. Strong-state power threshold of in-phase branch

[0045] The orthogonal branch threshold generation module is used to calculate the weak-state power threshold of orthogonal branches. Strong-state power threshold of orthogonal branches

[0046] The dual-branch power decision module, when the current P(Y) signal has not been enhanced, will adjust the average power P of the baseband signal in the same-phase branch. IB Weak-state power threshold of the in-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Strong-state power threshold of orthogonal branches The comparison is performed to determine whether the current P(Y) signal has transitioned to a power-enhanced state. If the current P(Y) signal has already been power-enhanced, the average power P of the baseband signal in the same phase branch is increased. IB Strong-state power threshold of the same-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Weak-state power threshold with orthogonal branches The comparison is performed, and the result is used to determine whether the current P(Y) signal has switched to a non-power-boosted state.

[0047] Preferably, the average power calculation module for the in-phase branch (I-branch) includes an in-phase branch low-pass filter and an incoherent integration and clearing module for the in-phase branch; the average power calculation module for the quadrature branch (Q-branch) includes an orthogonal branch low-pass filter and an incoherent integration and clearing module for the quadrature branch.

[0048] The in-phase branch low-pass filter reduces the in-phase branch signal u. I (n) After filtering, the in-phase branch baseband signal u is obtained. IB (n);

[0049] The orthogonal branch low-pass filter converts the orthogonal branch signal u Q (n) After filtering, the orthogonal branch baseband signal u is obtained. QB (n);

[0050] The in-phase branch incoherent integration and clearing module converts the in-phase branch baseband signal u... IB (n) Perform incoherent integration to obtain the average power P of the baseband signal in the in-phase branch. IB ;

[0051] The orthogonal branch incoherent integration and clearing module converts the orthogonal branch baseband signal u... QB(n) Perform incoherent integration to obtain the average power P of the baseband signal of the orthogonal branch. QB .

[0052] The advantages of this invention compared to the prior art are:

[0053] (1) The P(Y) signal power enhancement monitoring method proposed in this invention extends the GPS civilian signal carrier tracking loop and can detect P(Y) signal power enhancement behavior without relying on codeless and semi-codeless technology. It avoids being affected by related GPS signal characteristic policies and actions and has long-term and stable application performance.

[0054] (2) This invention uses an L-band antenna to receive GPS signals, eliminating the need for high-gain antennas with diameters of tens of meters. It has advantages such as low development cost, flexible equipment deployment, and ease of implementation through modification of existing equipment. Attached Figure Description

[0055] Figure 1 This is a block diagram illustrating the power enhancement monitoring principle based on civilian signal carrier tracking in an embodiment of the present invention. Detailed Implementation

[0056] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0057] 1. Average power of two branches

[0058] The L-band antenna receives the GPS satellite navigation signals to be observed and sends them to the radio frequency front-end processing module.

[0059] The radio frequency (RF) front-end processing module performs bandpass filtering, down-conversion, amplification, and analog-to-digital conversion on the GPS satellite navigation signal to obtain a GPS satellite navigation digital signal, which is then fed into the L1C / A (or L2C) signal carrier tracking loop. The GPS satellite navigation digital signal is an RF or intermediate frequency (IF) sampled signal.

[0060] There are no special requirements for the RF front-end processing module and the L1C / A signal (or L2C signal) carrier tracking loop; they can be the same as the RF front-end processing module of a civilian signal receiver.

[0061] The expression for the RF or IF sampled signal at the inlet of the carrier tracking loop is as follows:

[0062]

[0063] Among them, 2sI (n) represents the GPS signal in phase branch baseband signal, including P(Y) baseband signal and M baseband signal; 2s Q (n) represents the baseband signal of the orthogonal branch of the GPS signal, including the L1C / A (or L2C) baseband signal and the intermodulation component baseband signal; ω is the radio frequency or intermediate frequency; n is the sampling point number; ε represents the carrier phase; ε represents noise.

[0064] After the carrier tracking loop stably tracks the L1C / A signal (or L2C signal), it generates a local carrier that is in phase and frequency with the RF or IF signal. The RF or IF signal and the local carrier are then mixed by a quadrature mixer, and the output is as follows:

[0065]

[0066] Where, ω e For carrier frequency tracking error, This represents the carrier phase tracking error.

[0067] The output signal of each mixer is split into two paths: one path is sent to the correlator of the carrier tracking loop, and the other path is sent to the power enhancement monitoring data processing module. Within the power enhancement monitoring data processing module, the quadrature mixer output signal is filtered by a low-pass filter to form the following baseband signal:

[0068]

[0069] Among them, u IB (n) represents the baseband signal of the in-phase branch, u QB (n) represents the baseband signal of the orthogonal branch, ε I For in-phase branch noise, ε Q This is orthogonal branch noise.

[0070] The baseband signals of the two branches are incoherently integrated separately to obtain the average power of the two branches (including baseband signal and noise):

[0071]

[0072] Where N is the number of sampling points included in the incoherent integral. P IB P QB These are the average baseband signal power of in-phase and quadrature branches, respectively.

[0073] 2. Weak-state branch power threshold

[0074] Given the false alarm probability Pr of the target FaG The weak-state branch power threshold reference value Th w,Id satisfy:

[0075]

[0076] Where, N w This represents the number of sampling points included in the incoherent integral of the weak-state branch. x represents the average power random variable.

[0077] Given the target detection probability Pr DeG The weak-state branch power threshold reference value Th w,Id satisfy:

[0078]

[0079] in The following formula is used to derive:

[0080]

[0081] in, The average power of the navigation signal contained in the weak-state branch. The average power of the navigation signal increases after the branch transitions from a weak state to a strong state. This represents the power of the noise contained in the weak-state branch.

[0082] Based on equations (5) and (6), N can be determined by numerical iteration. w and Th w,Id .

[0083] When the weak-state branch is an in-phase branch, N w The value is the number of sampling points included in the incoherent integral of the in-phase branch, Th w,Id The value is taken as the reference value for the power threshold of the same-phase branch; The value is taken as the average power of the navigation signals contained in the in-phase branch. The value is the average increase in navigation signal power after the in-phase branch transitions from a weak state to a strong state. The value is the power of the noise contained in the same phase branch.

[0084] When the weak-state branch is an orthogonal branch, N w The value is the number of sampling points included in the incoherent integral of the orthogonal branch, Th w,Id The value is taken as the reference value for the power threshold of the orthogonal branch; The value is taken as the average power of the navigation signals contained in the orthogonal branches. The value is the average increase in navigation signal power after the orthogonal branch transitions from a weak state to a strong state. The value is the power of the noise contained in the orthogonal branch.

[0085] The weak-state power threshold of the in-phase branch Weak-state power threshold of orthogonal branches The following formula is used to calculate:

[0086]

[0087] Among them, P w (i) represents the average power sample of the weak-state branch, where i is the sample number and N is the average power sample index. P The number of samples for average power.

[0088] Calculate the weak-state power threshold of the in-phase branch At that time, P w (i) represents the average power sample of the baseband signal of the in-phase branch.

[0089] Calculate the weak-state power threshold of orthogonal branches At that time, P w (i) represents the average power sample of the baseband signal of the orthogonal branch.

[0090] In a specific embodiment of the present invention, a target false alarm probability Pr is set. FaG =1×10 -9 Target detection probability Pr DeG =97%, Based on the above formula, the number of sampling points N for the incoherent integral of the weak-state branch is obtained. w =1.3×10 5 The weak-state branch power threshold reference value Th w,Id =1.0236. N P The value is 30.

[0091] 3. Strong-state branch power threshold

[0092] Given the false alarm probability Pr of the target FaG Strong-state branch power threshold reference value Th s,Id satisfy:

[0093]

[0094] Where, N s The number of sampling points included in the incoherent integral of the strong-state branch. The following formula is used to derive:

[0095]

[0096] in, The average power of the navigation signal contained in the strong-state branch. The average power of the navigation signal decreases after the branch transitions from a strong state to a weak state. The power of the noise contained in the strong-state branch;

[0097] Given the target detection probability Pr DeG Strong-state branch power threshold reference value Th s,Id Satisfy the following formula:

[0098]

[0099] According to equations (9) and (11), N can be determined by numerical iteration. s and Th s,Id .

[0100] When the strong-state branch is an in-phase branch, N s The value is the number of sampling points included in the incoherent integral of the in-phase branch, Th s,Id The value is taken as the reference value for the power threshold of the same-phase branch; The value is taken as the average power of the navigation signals contained in the in-phase branch. The value is the decrease in the average power of the navigation signal after the in-phase branch transitions from a strong state to a weak state. The value is the power of the noise contained in the same phase branch.

[0101] When the strong-state branch is an orthogonal branch, N s The value is the number of sampling points included in the incoherent integral of the orthogonal branch, Th s,Id The value is taken as the reference value for the power threshold of the orthogonal branch; The value is taken as the average power of the navigation signals contained in the orthogonal branches. The value is the decrease in the average power of the navigation signal after the orthogonal branch transitions from a strong state to a weak state. The value is the power of the noise contained in the orthogonal branch.

[0102] The strong-state power threshold of the in-phase branch Strong-state power threshold of orthogonal branches It is calculated using the following formula:

[0103]

[0104] Among them, Th s,Id P is the reference value for the strong-state branch power threshold. s (j) represents the average power sample of the strong-state branch, where j is the sample number and N is the average power sample index. P The number of samples for average power.

[0105] Calculate the strong-state power threshold of the in-phase branch At that time, P s (j) represents the average power sample of the baseband signal of the in-phase branch.

[0106] Calculate the strong-state power threshold of orthogonal branches At that time, P s (j) represents the average power sample of the baseband signal of the orthogonal branch.

[0107] In a specific embodiment of the present invention, a target false alarm probability Pr is set. FaG =1×10-9 Target detection probability Pr DeG =97%, The number of sampling points N for the incoherent integral of the strong-state branch is obtained from the above formula. s =1.3×10 5 Strong-state branch power threshold reference value Th s,Id =1.0074. N P The value is 30.

[0108] (4) Dual-branch power decision

[0109] When the P(Y) signal power is not increased, the in-phase branch of the GPS signal is in a weak state, and the quadrature branch is in a strong state; when the P(Y) signal power is increased, the in-phase branch of the GPS signal is in a strong state, and the quadrature branch is in a weak state.

[0110] If the current P(Y) signal is not boosted, then first calculate the dual-branch power threshold. in, For the weak-state power threshold of the in-phase branch, This is the strong-state power threshold for the orthogonal branch. Then [P] IB ,P QB ]and The comparison is performed as follows: if the following condition is met, the current P(Y) signal is determined to be in a power-boosting state; otherwise, the current P(Y) signal is determined to be in a non-power-boosting state.

[0111]

[0112] If the current P(Y) signal has been boosted, then first calculate the dual-branch power threshold. in, For the strong-state power threshold of the in-phase branch, This is the weak-state power threshold for the orthogonal branch. Then, [P] IB ,P QB ]and The comparison is performed as follows: if the following condition is met, the current P(Y) signal is determined to be in a non-power-boosting state; otherwise, the current P(Y) signal is determined to be in a power-boosting state.

[0113]

[0114] In summary, this invention proposes a GPS P(Y) signal power enhancement monitoring method based on civilian signal carrier tracking, which includes the following steps:

[0115] S1. After bandpass filtering, down-conversion, amplification, and analog-to-digital conversion of the GPS satellite navigation signal received by the L-band antenna, a GPS satellite navigation digital signal is obtained; the GPS satellite navigation digital signal is a radio frequency or intermediate frequency sampled signal.

[0116] S2. A carrier tracking loop is used to stably track the civilian satellite navigation signal, generating a local carrier with the same frequency and phase as the GPS satellite navigation digital signal. The GPS satellite navigation digital signal and the local carrier are orthogonally mixed, and the in-phase branch signal u is output. I (n) and the orthogonal branch signal u Q (n); The civilian satellite navigation signal is an L1C / A signal or an L2C signal;

[0117] S3, transfer the in-phase branch signal u I (n), Orthogonal branch signal u Q (n) Perform low-pass filtering and incoherent integration respectively to obtain the average power P of the baseband signal in the in-phase branch. IB Average power P of baseband signal in orthogonal branches QB ;

[0118] S4. Calculate the weak-state power threshold of the in-phase branch. Strong-state power threshold of in-phase branch Weak-state power threshold of orthogonal branches Strong-state power threshold of orthogonal branches

[0119] S5. When the current P(Y) signal is not boosted, the average power P of the baseband signal in the same phase branch will be increased. IB Weak-state power threshold of the in-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Strong-state power threshold of orthogonal branches The comparison is performed to determine whether the current P(Y) signal has switched to a power enhancement state.

[0120] S6. When the current P(Y) signal has been enhanced, the average power P of the baseband signal in the same phase branch will be increased. IB Strong-state power threshold of the same-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Weak-state power threshold with orthogonal branches The comparison is performed, and the result is used to determine whether the current P(Y) signal has switched to a non-power-boosted state.

[0121] like Figure 1 As shown, a GPS P(Y) signal power enhancement monitoring device based on civilian signal carrier tracking is included. The device includes an L-band antenna, a radio frequency front-end processing module, a civilian signal carrier tracking loop, a dual-branch power decision module, an in-phase branch average power calculation module, an orthogonal branch average power calculation module, an in-phase branch threshold generation module, and an orthogonal branch threshold generation module.

[0122] The L-band antenna receives the GPS satellite navigation signals to be observed and sends them to the radio frequency front-end processing module.

[0123] The radio frequency front-end processing module performs bandpass filtering, down-conversion, amplification, and analog-to-digital conversion on the GPS satellite navigation signal received by the L-band antenna to obtain a GPS satellite navigation digital signal, which is then sent to the carrier tracking loop; the GPS satellite navigation digital signal is a radio frequency or intermediate frequency sampling signal.

[0124] The civilian signal carrier tracking loop is used to stably track civilian satellite navigation signals, generate a local carrier with the same frequency and phase as the GPS satellite navigation digital signal, and output the in-phase branch signal u after orthogonal mixing of the GPS satellite navigation digital signal and the local carrier. I (n) and the orthogonal branch signal u Q (n); The civilian satellite navigation signal is an L1C / A signal or an L2C signal;

[0125] The in-phase branch average power calculation module calculates the in-phase branch signal u. I (n) Perform low-pass filtering and incoherent integration to obtain the average power P of the baseband signal in the in-phase branch. IB ;

[0126] The orthogonal branch average power calculation module calculates the orthogonal branch signal u. Q (n) Perform low-pass filtering and incoherent integration to obtain the average power P of the baseband signal in the orthogonal branch. QB ;

[0127] The in-phase branch threshold generation module is used to calculate the weak-state power threshold of in-phase branches. Strong-state power threshold of in-phase branch

[0128] The orthogonal branch threshold generation module is used to calculate the weak-state power threshold of orthogonal branches. Strong-state power threshold of orthogonal branches

[0129] The dual-branch power decision module, when the current P(Y) signal has not been enhanced, will adjust the average power P of the baseband signal in the same-phase branch. IB Weak-state power threshold of the in-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Strong-state power threshold of orthogonal branches The comparison is performed to determine whether the current P(Y) signal has transitioned to a power-enhanced state. If the current P(Y) signal has already been power-enhanced, the average power P of the baseband signal in the same phase branch is increased. IB Strong-state power threshold of the same-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch.QB Weak-state power threshold with orthogonal branches The comparison is performed, and the result is used to determine whether the current P(Y) signal has switched to a non-power-boosted state.

[0130] The average power calculation module for the in-phase branch (I-branch) includes an in-phase branch low-pass filter and an incoherent integration and clearing module for the in-phase branch; the average power calculation module for the quadrature branch (Q-branch) includes an orthogonal branch low-pass filter and an incoherent integration and clearing module for the quadrature branch.

[0131] The in-phase branch low-pass filter reduces the in-phase branch signal u. I (n) After filtering, the in-phase branch baseband signal u is obtained. IB (n);

[0132] The orthogonal branch low-pass filter converts the orthogonal branch signal u Q (n) After filtering, the orthogonal branch baseband signal u is obtained. QB (n);

[0133] The in-phase branch incoherent integration and clearing module converts the in-phase branch baseband signal u... IB (n) Perform incoherent integration to obtain the average power P of the baseband signal in the in-phase branch. IB ;

[0134] The orthogonal branch incoherent integration and clearing module converts the orthogonal branch baseband signal u... QB (n) Perform incoherent integration to obtain the average power P of the baseband signal of the orthogonal branch. QB .

[0135] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A GPS P(Y) signal power enhancement monitoring method based on civil signal tracking, characterized in that Includes the following steps: S1. After bandpass filtering, down-conversion, amplification, and analog-to-digital conversion of the GPS satellite navigation signal received by the L-band antenna, a GPS satellite navigation digital signal is obtained; the GPS satellite navigation digital signal is a radio frequency or intermediate frequency sampled signal. S2. Use a carrier tracking loop to stably track the civil satellite navigation signal, generate a local carrier that is of the same frequency and in-phase with the GPS satellite navigation digital signal, and output the in-phase branch signal u I (n) and the quadrature branch signal u Q (n); the civil satellite navigation signal is an L1C / A signal or an L2C signal; S3. Filter the in-phase branch signal u I (n) and the quadrature branch signal u Q (n) respectively by low-pass filtering and non-coherent integration to obtain the average power P IB of the in-phase baseband signal and the average power P QB of the quadrature baseband signal; S4. Calculate the weak-state power threshold of the in-phase branch Strong-state power threshold of the in-phase branch Weak-state power threshold of the quadrature branch Strong-state power threshold of the quadrature branch When the current P(Y) signal is not power-enhanced, the average power P of the in-phase baseband signal IB is compared with the weak-state power threshold of the in-phase branch and the average power P of the quadrature baseband signal QB is compared with the strong-state power threshold of the quadrature branch to determine whether the current P(Y) signal is converted to the power-enhanced state according to the comparison result; S6. When the current P(Y) signal has been power enhanced, average power P of the in-phase branch baseband signal IB is compared with the strong-state power threshold of the in-phase branch and average power P of the quadrature branch baseband signal QB is compared with the weak-state power threshold of the quadrature branch to determine whether the current P(Y) signal switches to the non-power-enhanced state according to the comparison result.

2. The GPS P(Y) signal power enhancement monitoring method based on civil signal carriers according to claim 1, characterized in that In step S5, if the following equation is satisfied, the current P(Y) signal is determined to be in a power-enhanced state; otherwise, the current P(Y) signal is determined to be in a non-power-enhanced state:

3. The GPS P(Y) signal power enhancement monitoring method based on civilian signal carrier according to claim 1, characterized in that... In step S6, if the following equation is satisfied, the current P(Y) signal is determined to be in a non-power-boosting state; otherwise, the current P(Y) signal is determined to be in a power-boosting state:

4. The GPS P(Y) signal power enhancement monitoring method based on civilian signal carrier according to claim 1, characterized in that... The weak-state power threshold of the in-phase branch Weak-state power threshold of orthogonal branches The following formula is used to calculate: Among them, Th w,Id is the weak state branch power threshold reference value, P w (i) is the average power sample of the weak state branch, i is the average power sample serial number, N P is the sample quantity of the average power.

5. The GPS P(Y) signal power enhancement monitoring method based on civilian signal carrier according to claim 1, characterized in that... The strong-state power threshold of the in-phase branch Strong-state power threshold of orthogonal branches It is calculated using the following formula: Among them, Th s,Id is the strong-state branch power threshold reference value, P s (j) is the strong-state branch average power sample, j is the average power sample serial number, N P is the sample quantity of the average power.

6. The GPS P(Y) signal power enhancement monitoring method based on civilian signal carrier according to claim 1, characterized in that: Given the target false alarm probability Pr FaG , the weak state branch power threshold reference value Th w,Id satisfies the following conditions: where N w is the number of samples included in the non-coherent integration of the weak state branch; x represents the average power random variable; Given the target detection probability Pr DeG , the weak state branch power threshold reference value Th w,Id satisfies: in The following formula is used to derive: in, The average power of the navigation signal contained in the weak-state branch. The average power of the navigation signal increases after the branch transitions from a weak state to a strong state. This represents the power of the noise contained in the weak-state branch.

7. The GPS P(Y) signal power enhancement monitoring method based on civilian signal carrier according to claim 1, characterized in that: Given the target false alarm probability Pr FaG , the strong state branch power threshold reference value Th s,Id satisfies: Where, N s Let x be the number of sampling points included in the incoherent integral of the strong-state branch, and let x represent the average power random variable. The following formula is used to derive: in, The average power of the navigation signal contained in the strong-state branch. The average power of the navigation signal decreases after the branch transitions from a strong state to a weak state. The power of the noise contained in the strong-state branch; Given the target detection probability Pr DeG , the strong state branch power threshold reference value Th s,Id satisfies the following formula:

8. A GPS P(Y) signal power enhancement and monitoring device based on civilian signal tracking, characterized in that... It includes an L-band antenna, a radio frequency front-end processing module, a civilian signal carrier tracking loop, a dual-branch power decision module, an in-phase branch average power calculation module, an orthogonal branch average power calculation module, an in-phase branch threshold generation module, and an orthogonal branch threshold generation module. The L-band antenna receives the GPS satellite navigation signals to be observed and sends them to the radio frequency front-end processing module. The radio frequency front-end processing module performs bandpass filtering, down-conversion, amplification, and analog-to-digital conversion on the GPS satellite navigation signal received by the L-band antenna to obtain a GPS satellite navigation digital signal, which is then sent to the carrier tracking loop; the GPS satellite navigation digital signal is a radio frequency or intermediate frequency sampling signal. A civil signal carrier tracking loop is used to stably track civil satellite navigation signals, generate a local carrier with the same frequency and phase as the GPS satellite navigation digital signal, and orthogonally mix the GPS satellite navigation digital signal with the local carrier to output the in-phase branch signal u I (n) and the quadrature branch signal u Q (n); the civil satellite navigation signal is an L1C / A signal or an L2C signal; In-phase branch average power calculation module, which performs low-pass filtering and non-coherent integration on the in-phase branch signal u I (n) to obtain the average power P IB ; Quadrature branch average power calculation module, which performs low-pass filtering and non-coherent integration on the quadrature branch signal u Q (n) to obtain the average power P of the quadrature branch baseband signal QB ; The in-phase branch threshold generation module is used to calculate the weak-state power threshold of in-phase branches. Strong-state power threshold of in-phase branch The orthogonal branch threshold generation module is used to calculate the weak-state power threshold of orthogonal branches. Strong-state power threshold of orthogonal branches The dual-branch power decision module, when the current P(Y) signal has not been enhanced, will adjust the average power P of the baseband signal in the same-phase branch. IB Weak-state power threshold of the in-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Strong-state power threshold of orthogonal branches The comparison is performed to determine whether the current P(Y) signal has transitioned to a power-enhanced state. If the current P(Y) signal has already been power-enhanced, the average power P of the baseband signal in the same phase branch is increased. IB Strong-state power threshold of the same-phase branch Compare and assign the average power P of the baseband signal of the orthogonal branch. QB Weak-state power threshold with orthogonal branches The comparison is performed, and the result is used to determine whether the current P(Y) signal has switched to a non-power-boosted state.

9. The GPS P(Y) signal power enhancement monitoring device based on civilian signal tracking according to claim 8, characterized in that... The average power calculation module for the in-phase branch (I-branch) includes an in-phase branch low-pass filter and an incoherent integration and clearing module for the in-phase branch; the average power calculation module for the quadrature branch (Q-branch) includes an orthogonal branch low-pass filter and an incoherent integration and clearing module for the quadrature branch. The in-phase branch low-pass filter filters the in-phase branch signal u I (n) and obtains the in-phase branch baseband signal u IB (n); Orthogonal branch low-pass filter, after filtering the orthogonal branch signal u Q (n), the orthogonal branch baseband signal u QB (n) is obtained; In-phase branch non-coherent integration and clearing module, which performs non-coherent integration on the in-phase baseband signal u IB (n) to obtain the average power P of the in-phase baseband signal IB ; Orthogonal branch non-coherent integration and clearing module, which performs non-coherent integration on the orthogonal branch baseband signal u QB (n) to obtain the average power P of the orthogonal branch baseband signal QB .

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