CN117492036B - GNSS ground station signal intelligent receiving method based on interference monitoring assistance - Google Patents
GNSS ground station signal intelligent receiving method based on interference monitoring assistance Download PDFInfo
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- CN117492036B CN117492036B CN202311453803.8A CN202311453803A CN117492036B CN 117492036 B CN117492036 B CN 117492036B CN 202311453803 A CN202311453803 A CN 202311453803A CN 117492036 B CN117492036 B CN 117492036B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/21—Interference related issues ; Issues related to cross-correlation, spoofing or other methods of denial of service
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/35—Constructional details or hardware or software details of the signal processing chain
- G01S19/37—Hardware or software details of the signal processing chain
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The invention relates to the technical field of satellite navigation, in particular to an intelligent GNSS ground station signal receiving method based on interference monitoring assistance. The intelligent GNSS ground station signal receiving method based on the interference monitoring assistance is characterized by comprising the following steps of: (1) interference monitoring result extraction and treatment; (2) interference influence factor calculation: (3) estimation of carrier-to-noise ratio loss caused by interference: (4) carrier-to-noise ratio loss estimation of anti-interference introduction: and (5) intelligently switching signal receiving modes. In order to reduce the loss of the carrier-to-noise ratio of the signal, the invention comprehensively analyzes and judges according to the characteristic parameters such as the interference type, the interference power and the like provided by the interference monitoring module, and starts the anti-interference when the loss of the carrier-to-noise ratio caused by starting the anti-interference is smaller than the loss of the carrier-to-noise ratio caused by the interference, thereby realizing the optimal receiving of the signal.
Description
Technical Field
The invention relates to the technical field of satellite navigation, in particular to an intelligent GNSS ground station signal receiving method based on interference monitoring assistance.
Background
The global satellite navigation system (Global Navigation SATELLITE SYSTEM, GNSS) can provide all-weather, all-day, high-precision positioning, navigation and timing services for global users. Currently, the united states GPS system, the chinese beidou system, the european galileo system, and the russian GLONASS system are in service. The GNSS is composed of a space section, a ground section and a user section, wherein the space section mainly comprises navigation satellites, the ground section is composed of a main control station, an injection station, a monitoring station and other ground stations, and the user section comprises a GNSS receiving terminal, a module, a chip and the like.
As an important component of GNSS, the main functions of a GNSS ground station include: 1) Receiving and measuring signals broadcast by GNSS satellites, and further determining the running orbits of the satellites; 2) Calculating satellite clock difference and keeping clocks of all satellites synchronous with standard time (GPS time or Beidou time); 3) Updating the navigation message of the satellite in a wireless injection mode; 4) A control command to adjust the orbit of the satellite is transmitted as necessary, the satellite is ensured to travel along a predetermined orbit, and so on. It can be seen that the signal receiving quality and measurement accuracy of the GNSS ground station directly determine the service accuracy of the whole system.
In order to improve the signal receiving quality and measuring precision of the GNSS ground station, the signal processing loss of each link of the receiving link is required to be reduced as much as possible, and the carrier-to-noise ratio of the signal is improved. In order to deal with the threat of electromagnetic interference, a GNSS ground station is generally integrated with an interference monitoring module and an interference suppression module, wherein the interference monitoring module can detect whether electromagnetic interference exists in the environment, judge the interference type and estimate the characteristic parameters of the interference, and the interference suppression module can reject the interference.
It is known that interference causes a degradation of the signal-to-noise ratio and this is a gradual process, in particular the signal-to-noise ratio will gradually decrease with increasing interference power and the degree of decrease is closely related to the specific interference type. On the other hand, if there is interference in the receiving link, the signal components with the same frequency as the interference are inevitably removed while the anti-interference is started to remove the interference, so that the signal carrier-to-noise ratio is deteriorated. Therefore, those skilled in the art are constantly researching how to optimize the handling of interference.
Disclosure of Invention
The technical problem to be solved by the invention is to provide an intelligent GNSS ground station signal receiving method based on interference monitoring assistance, which is used for estimating signal carrier-to-noise ratio loss caused by interference and carrier-to-noise ratio loss caused by interference rejection in real time according to the interference type, interference power and other characteristic parameters provided by an interference monitoring module of the GNSS ground station, so as to determine whether to start anti-interference and realize optimal signal receiving, thereby improving signal receiving quality and measuring accuracy.
The technical scheme of the invention provides an intelligent GNSS ground station signal receiving method based on interference monitoring assistance, which is characterized by comprising the following steps:
(1) Interference monitoring result extraction and disposal
Firstly, according to an interference monitoring result provided by an interference monitoring module, the following processing is performed:
If no interference is detected, directly jumping to the step (5);
If interference is detected, processing is performed according to the interference type: if the interference is pulse interference, extracting interference power, pulse period, pulse duration and interference power spectral density from the interference monitoring result. And if the continuous wave interference exists, extracting interference power, interference center frequency, interference bandwidth and interference power spectral density from the interference monitoring result.
Among them, the interference detection method and the interference parameter estimation method have abundant research results in the field, and reference may be made to literature "Impact and Detection of GNSS Jammers on Consumer Grade Satellite Navigation Receivers,Daniele Borio,Proceedings of The IEEE,2016".
(2) Interference impact factor calculation
For impulse interference, the interference impact factor is calculated as follows:
wherein R C is the spread spectrum code rate of GNSS signals, which is a public known parameter. G S (f) is the normalized power spectral density of the GNSS signal, a publicly known function. τ, T and G J (f) are the pulse duration, pulse period and power spectral density of the impulse interference, respectively, which are parameters extracted from the interference monitoring result according to step (1).
For continuous wave interference, the interference impact factor is calculated as follows:
(3) Interference-induced carrier-to-noise ratio loss estimation
And estimating the signal carrier-to-noise ratio loss caused by interference according to the interference power and the interference influence factor. The carrier-to-noise loss is estimated according to the following equation:
Where Δ 1 is the signal-to-noise loss in dB. P J is the interference power, which is a parameter extracted from the interference monitoring result according to step (1), and is given in W. N 0 is the noise power density, and typically an empirical value of-174 dBm/Hz is available.
(4) Anti-interference introduced carrier-to-noise ratio loss estimation
For impulse interference, the carrier-to-noise loss introduced by the anti-interference is estimated according to the following formula:
for continuous wave interference, the carrier-to-noise ratio loss introduced by the anti-interference is estimated according to the following formula:
Where f 0 is the center frequency of the interference and B is the bandwidth of the interference.
(5) Intelligent switching of signal receiving modes
If no interference is detected or the carrier-to-noise ratio loss delta 2 introduced by anti-interference is larger than the carrier-to-noise ratio loss delta 1 caused by interference, the direct processing is performed, namely the anti-interference is not started, and the subsequent acquisition tracking is directly performed on the received data. If interference is detected and carrier-to-noise ratio loss delta 2 caused by the interference is smaller than or equal to carrier-to-noise ratio loss delta 1 caused by the interference, starting the anti-interference, performing interference suppression on the received data, and then performing subsequent acquisition tracking processing.
The anti-interference method has abundant research results in the field, and can refer to the literature pulse, narrow band and composite interference detection and inhibition technology thereof, huo Shumin, doctor's treatises, 2015 and the like.
The beneficial effects of the invention are as follows: the intelligent receiving method for the GNSS ground station signals based on the interference monitoring assistance can optimize the receiving mode of the signals according to the parameters provided by the GNSS ground station interference monitoring module, reduce the carrier-to-noise ratio loss in the signal processing process, and further improve the receiving quality and the measuring accuracy of the signals.
In order to reduce the loss of the carrier-to-noise ratio of the signal, the invention comprehensively analyzes and judges according to the characteristic parameters such as the interference type, the interference power and the like provided by the interference monitoring module, and starts the anti-interference when the loss of the carrier-to-noise ratio caused by starting the anti-interference is smaller than the loss of the carrier-to-noise ratio caused by the interference, thereby realizing the optimal receiving of the signal.
Drawings
FIG. 1 is a flow chart of an intelligent GNSS ground station signal receiving method based on interference monitoring assistance;
Fig. 2 is a graph of carrier-to-noise ratio loss during receiving a GNSS ground station signal obtained by the method of the present invention.
Detailed Description
The invention will be further described with reference to the drawings and examples.
Fig. 1 is a flowchart of a GNSS ground station signal intelligent receiving method based on interference monitoring assistance, as shown in the figure, comprising the following steps:
Step S11, interference monitoring result extraction and disposal
Firstly, according to an interference monitoring result provided by an interference monitoring module, the following processing is performed:
If no interference is detected, directly jumping to the step S15;
If interference is detected, processing is performed according to the interference type: if the interference is pulse interference, extracting interference power, pulse period, pulse duration and interference power spectral density from the interference monitoring result. And if the continuous wave interference exists, extracting interference power, interference center frequency, interference bandwidth and interference power spectral density from the interference monitoring result.
Step S12, interference influence factor calculation
For impulse interference, the interference impact factor is calculated as follows:
wherein R C is the spread spectrum code rate of GNSS signals, which is a public known parameter. G S (f) is the normalized power spectral density of the GNSS signal, a publicly known function. τ, T and G J (f) are the pulse duration, pulse period and power spectral density of the impulse interference, respectively, which are parameters extracted from the interference monitoring result according to step (1).
For continuous wave interference, the interference impact factor is calculated as follows:
Step S13, estimating the carrier-to-noise ratio loss caused by interference
And estimating the signal carrier-to-noise ratio loss caused by interference according to the interference power and the interference influence factor. The carrier-to-noise loss is estimated according to the following equation:
Where Δ 1 is the signal-to-noise loss in dB. P J is the interference power, which is a parameter extracted from the interference monitoring result according to step (1), and is given in W. N 0 is the noise power density, and typically an empirical value of-174 dBm/Hz is available.
Step S14, estimating the carrier-to-noise ratio loss introduced by anti-interference
For impulse interference, the carrier-to-noise loss introduced by the anti-interference is estimated according to the following formula:
for continuous wave interference, the carrier-to-noise ratio loss introduced by the anti-interference is estimated according to the following formula:
Where f 0 is the center frequency of the interference and B is the bandwidth of the interference.
Step S15, intelligent switching of signal receiving modes
If no interference is detected or the carrier-to-noise ratio loss delta 2 introduced by anti-interference is larger than the carrier-to-noise ratio loss delta 1 caused by interference, the direct processing is performed, namely the anti-interference is not started, and the subsequent acquisition tracking is directly performed on the received data. If interference is detected and carrier-to-noise ratio loss delta 2 caused by the interference is smaller than or equal to carrier-to-noise ratio loss delta 1 caused by the interference, starting the anti-interference, performing interference suppression on the received data, and then performing subsequent acquisition tracking processing.
Fig. 2 is a diagram of carrier-to-noise ratio loss in the process of receiving a Beidou ground station signal obtained by the method. In this embodiment, the beidou ground station receives the beidou No. three B3I signal, and the specific signal format can be referred to the beidou satellite navigation system space signal interface control file (ICD file) issued by the beidou official network, the signal center frequency is 1268.52MHz, the spreading code rate is 10.23Mcps, and the signal level of the beidou ground station antenna port surface is-130 dBm. The antenna has a narrow band Gaussian interference, the bandwidth is 4MHz, the center frequency is 1268.52MHz, the antenna gradually approaches to the ground station of the north bucket, and the interference power reaching the antenna of the ground station is 10dB greater than the power of the Beidou signal at the beginning. The blue curve in fig. 2 shows the loss of the carrier-to-noise ratio of the ground station received signal when the anti-interference is always turned on, which is also the conventional practice, and the red curve shows the loss of the carrier-to-noise ratio of the ground station received signal obtained by the method of the present invention, and it can be seen that the loss of the carrier-to-noise ratio obtained by the method of the present invention is smaller than that obtained by the conventional method when the interference-to-noise ratio is smaller than 26dB, especially when the interference-to-noise ratio is smaller, the method of the present invention can reduce the loss of the signal carrier-to-noise ratio by about 2.4dB, and when the interference-to-noise ratio exceeds 26dB, the performances of the two methods are consistent.
The above description of the preferred embodiments of the present invention has been included to describe in detail the technical features of the present invention, and is not intended to limit the invention to the specific forms described in the embodiments, and other modifications and variations according to the gist of the present invention are also protected by this patent. The gist of the present disclosure is defined by the claims, not by the specific description of the embodiments.
Claims (3)
1. The intelligent GNSS ground station signal receiving method based on the interference monitoring assistance is characterized by comprising the following steps of:
(1) Interference monitoring result extraction and treatment:
Firstly, according to an interference monitoring result provided by an interference monitoring module, the following processing is performed:
if no interference is detected, directly jumping to the step (5);
If interference is detected, processing is performed according to the interference type: if the interference is pulse interference, extracting interference power, pulse period and pulse duration from an interference monitoring result, and extracting interference power spectral density; if continuous wave interference is adopted, extracting interference power, interference center frequency, interference bandwidth and interference power spectral density from an interference monitoring result;
(2) Interference influence factor calculation: based on whether the disturbance is a pulsed disturbance or a continuous wave disturbance, a disturbance influencing factor is calculated,
(3) Estimation of carrier to noise ratio loss due to interference:
Estimating signal carrier-to-noise ratio loss caused by interference according to interference power and interference influence factors; the carrier-to-noise loss is estimated according to the following equation:
，
In the method, in the process of the invention, The unit is dB for signal carrier-to-noise ratio loss; The interference power is a parameter extracted from an interference monitoring result according to the step (1), and the unit is W; taking the tested value of-174 dBm/Hz as the noise power density;
(4) And (3) estimating carrier-to-noise ratio loss caused by anti-interference:
For impulse interference, the carrier-to-noise loss introduced by the anti-interference is estimated according to the following formula:
，
、 pulse duration and pulse period of pulse interference respectively;
for continuous wave interference, the carrier-to-noise ratio loss introduced by the anti-interference is estimated according to the following formula:
，
In the method, in the process of the invention, For the center frequency of the interference, B is the bandwidth of the interference,Normalized power spectral density for GNSS signals;
(5) Intelligent switching of signal receiving modes:
If no interference is detected, or the carrier-to-noise ratio loss caused by anti-interference Greater than the carrier to noise ratio loss caused by interferenceThen, the direct processing is carried out, namely, the anti-interference is not started, and the subsequent capturing and tracking are directly carried out on the received data; if interference is detected and the carrier-to-noise ratio loss introduced by the interference is resistedLess than or equal to carrier-to-noise ratio loss caused by interferenceAnd starting anti-interference, performing interference suppression on the received data, and then performing subsequent capture tracking processing.
2. The intelligent receiving method of GNSS ground station signals based on interference monitoring assistance according to claim 1, wherein in the interference influence factor calculation, for impulse interference, the interference influence factor Q is calculated according to the following formula:
，
In the method, in the process of the invention, The code rate of the spread spectrum code of the GNSS signal is a publicly known parameter; normalized power spectral density for GNSS signals, a publicly known function; 、 And The pulse duration, pulse period and power spectral density of the pulse interference are parameters extracted from the interference monitoring result according to the step (1).
3. The intelligent receiving method of GNSS ground station signals based on interference monitoring assistance according to claim 1, wherein in the interference influence factor calculation, for continuous wave interference, the interference influence factor Q is calculated according to the following formula:
，
In the method, in the process of the invention, The code rate of the spread spectrum code of the GNSS signal is a publicly known parameter; normalized power spectral density for GNSS signals, a publicly known function; 、 And The pulse duration, pulse period and power spectral density of the pulse interference are parameters extracted from the interference monitoring result according to the step (1).
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