CN102087353B - Method and equipment for suppressing interference - Google Patents

Abstract

The invention discloses a method and equipment for suppressing interference, belonging to the field of wireless communication. The method includes: adjusting the filtering threshold and the signal threshold according to the location of the receiving end, the external environment, and signal propagation error factors; removing suppressive interference whose frequency spectrum exceeds the filter threshold from the intercepted signal; when the suppressive interference in the signal is of broadband type, obtaining an interference cancellation signal, and using the interference cancellation signal to remove the suppressive interference from the signal Interference: according to the signal threshold, determine whether the signal is fraudulent interference, if yes, discard the signal, and if not, then the signal is a normal signal. The present invention can suppress the interference even when the characteristics of the interference are not known in advance, can suppress the broadband interference and effectively suppress the fraudulent interference.

Description

A method and device for suppressing interference

technical field

The invention relates to the field of wireless communication, in particular to a method and equipment for suppressing interference.

Background technique

The global satellite navigation system is an important information base and strategic facility for all countries, and has been widely used in key fields such as national defense. In military applications and some civilian fields, high requirements are put forward for the integrity and continuity of satellite navigation. However, due to the extremely weak power of the navigation satellite signal reaching the ground, the satellite navigation receiving end is easily interfered; especially the man-made suppressive interference and deceptive interference have brought huge hidden dangers to the application.

For suppressive interference, there are currently several suppression methods, including:

The first method: a signal related to the suppressed interference signal is generated at the receiving end, and the signal is superimposed on the signal received by the receiving end through an adaptive filter to eliminate the suppressed interference signal.

The second type: use multi-element antenna array to suppress interference, specifically: the multi-array element antenna array includes multiple antennas, and each antenna is respectively connected to the microwave network and the processor. When there is suppressive interference in the signal, adjust the signal received by the antenna to zero to eliminate the interference.

For deceptive interference, the following methods can currently be used to suppress it, including:

The parameters of the satellite signal received by the receiving end include power, the integral value of the relevant channel, and the long radius of the orbit. Among them, each parameter has a normal working range, for example, the working range of the power is -110dBm to -133dBm, the working range of the relevant channel integral value is 5100 to 1821776 and the working range of the long radius of the track is 5.153600E+003 to 5.153699E +003. When a certain parameter extracted from the received signal exceeds the normal working range, it can be determined that the signal is a deceptive interference signal, and the signal is discarded directly.

In the process of realizing the present invention, the inventor finds that there are at least the following problems in the prior art:

For suppression interference:

In the above-mentioned first method, it is necessary to know the characteristics of the suppression interference signal in advance, so as to generate a signal related to it to realize interference cancellation, so it cannot be realized without knowing its characteristics.

In the above-mentioned second method, it is only applicable to narrow-band suppression interference, and wide-band suppression interference cannot be well suppressed.

For deceptive interference: It does not take into account that the parameters of the signal will change suddenly in different occasions and emergencies, so that the interference cannot be effectively suppressed.

Contents of the invention

In order to suppress interference without prior knowledge of interference characteristics, suppress broadband interference, and effectively suppress fraudulent interference, embodiments of the present invention provide a method and device for suppressing interference. Described technical scheme is as follows:

A method of suppressing interference, the method comprising:

Adjust the filtering threshold and signal threshold according to the location of the receiving end, the external environment and signal propagation error factors;

When the suppressive interference in the signal is of a narrowband type, the signal is intercepted by a window function, and the suppressive interference whose spectrum exceeds the filtering threshold is removed from the intercepted signal;

When the suppressive interference in the signal is of broadband type, obtaining an interference cancellation signal, and using the interference cancellation signal to remove the suppressive interference from the signal;

According to the signal threshold, determine whether the signal is deceptive interference, if yes, discard the signal, if not, then the signal is a normal signal;

Wherein, the intercepting the signal through a window function, and removing suppressive interference whose frequency spectrum exceeds the filtering threshold from the intercepted signal specifically includes:

Intercepting the signal through the window function, and performing fast Fourier transform on the intercepted signal to obtain a spectrum signal;

removing suppressive interference whose spectrum exceeds the filtering threshold from the spectral signal;

According to the trend and slope of the spectral lines in the spectral signal from which suppressive interference has been removed, a spectral graph is matched with the stored spectral graph, and a linear interpolation is performed with reference to the matched spectral graph to obtain a reconstructed signal;

Compensating the suppressed interference-removed spectral signal by using the reconstructed signal;

Inverse Fourier transform is performed on the compensated spectrum signal to obtain the intercepted signal.

The location of the receiving end includes at least latitude and longitude and altitude, the external environment where the receiving end is located includes at least air humidity and surrounding obstacles, the signal propagation error factors include at least ionospheric and tropospheric refraction, and the signal threshold includes at least Power range, time of arrival range, angle of arrival range or navigation parameter range;

Correspondingly, the adjustment of the filtering threshold and the signal threshold according to the location of the receiving end, the external environment and signal propagation error factors specifically includes:

adjusting the size of the power range according to changes in the ionosphere, the tropospheric refraction and/or the altitude;

Adjusting the size of the arrival time range according to changes in the latitude and longitude, the altitude, the ionosphere and/or the tropospheric refraction;

Adjusting the size of the arrival angle range according to changes in the ionosphere, the tropospheric refraction, the latitude and longitude and/or the altitude;

Adjusting the size of the navigation parameter range according to changes in the latitude and longitude, the ionosphere, the tropospheric refraction and/or the air humidity;

Adjusting the size of the filtering threshold according to changes in the ionosphere, the tropospheric refraction, the surrounding obstacles and/or the air humidity.

The acquiring the interference cancellation signal, and using the interference cancellation signal to remove suppressive interference from the signal specifically includes:

extracting characteristic parameters from the signal, the characteristic parameters including at least variance, mean, frequency and period;

Generating an interference cancellation signal related to the suppressed interference by linearly matching the characteristic parameters with the stored signal characteristics;

Adaptive filtering is performed on the interference canceling signal, and then the adaptively filtered interference canceling signal is superimposed on the signal to remove suppressive interference in the signal.

According to the signal threshold, determine whether the signal is deceptive interference, if yes, discard the signal, if not, then the signal is a normal signal, specifically including:

Judging whether the power of the signal is a value within the power range, if not, the signal is deceptive interference, and discarding the signal;

If it is a value within the power range, judge whether the arrival time of the signal is a value within the arrival time range, if not, the signal is deceptive interference, and discard the signal;

If it is a value within the arrival time range, judge whether the arrival angle of the signal is a value within the arrival angle range, if not, the signal is deceptive interference, and discard the signal;

If it is a value within the range of the angle of arrival, judge whether the navigation parameter of the signal is a value within the range of the navigation parameter, if not, the signal is deceptive interference, and discard the signal; if yes, the The signal is a normal signal from a satellite.

After adjusting the filter threshold and signal threshold according to the location of the receiving end, the external environment and signal propagation error factors, it also includes:

receiving a plurality of signals, the signals being at least four;

judging whether the signal-to-noise ratio of the signal exceeds a preset threshold;

If the number of signals exceeding the threshold is at least four, zeroing the signals not exceeding the threshold, and recording the direction of the signals not exceeding the threshold;

If the number of signals exceeding the threshold is less than four, discard all the signals, adjust the gain of the main lobe of the antenna pattern, and use the main lobe to receive signals again.

A device for suppressing interference, the device comprising:

The adjustment module is used to adjust the filtering threshold and the signal threshold according to the location of the receiving end, the external environment and signal propagation error factors;

The first removal module is configured to intercept the signal through a window function when the suppressive interference in the signal is of a narrowband type, and remove suppressive interference whose frequency spectrum exceeds the filtering threshold from the intercepted signal;

The second removal module is configured to obtain an interference cancellation signal when the suppressive interference in the signal is of a broadband type, and use the interference cancellation signal to remove the suppressive interference from the signal;

A determining module, configured to determine whether the signal is fraudulent interference according to the signal threshold, if yes, discard the signal, and if not, then the signal is a normal signal;

Wherein, the first removal module specifically includes:

An intercepting unit, configured to intercept the signal through the window function, and perform fast Fourier transform on the intercepted signal to obtain a spectrum signal;

a first removing unit, configured to remove suppressive interference whose spectrum exceeds the filtering threshold from the spectral signal;

The obtaining unit is configured to match the stored spectrogram with the stored spectrogram according to the direction and slope of the spectral line in the spectral signal from which suppressive interference has been removed, and perform linear interpolation with the matched spectrogram as a reference to obtain a re- structural signal;

a compensation unit, configured to use the reconstructed signal to compensate the spectral signal from which suppression-type interference is removed;

The transformation unit is configured to perform inverse Fourier transformation on the compensated spectrum signal to obtain the intercepted signal.

The location of the receiving end includes at least latitude and longitude and altitude, the external environment where the receiving end is located includes at least air humidity and surrounding obstacles, the signal propagation error factors include at least ionospheric and tropospheric refraction, and the signal threshold includes at least Power range, time of arrival range, angle of arrival range or navigation parameter range;

Correspondingly, the adjustment module specifically includes:

A first adjustment unit, configured to adjust the size of the power range according to changes in the ionosphere, the tropospheric refraction and/or the altitude;

A second adjustment unit, configured to adjust the size of the arrival time range according to changes in the latitude and longitude, the altitude, the ionosphere and/or the tropospheric refraction;

A third adjustment unit, configured to adjust the size of the arrival angle range according to changes in the ionosphere, the tropospheric refraction, the latitude and longitude, and/or the altitude;

A fourth adjustment unit, configured to adjust the size of the navigation parameter range according to changes in the latitude and longitude, the ionosphere, the tropospheric refraction and/or the air humidity;

The fifth adjustment unit is configured to adjust the size of the filtering threshold according to changes in the ionosphere, the tropospheric refraction, the surrounding obstacles and/or the air humidity.

The second removal module specifically includes:

An extraction unit, configured to extract characteristic parameters from the signal, the characteristic parameters at least including variance, mean, frequency and period;

A linear matching unit, configured to linearly match the characteristic parameters with the stored signal characteristics to generate an interference cancellation signal related to the suppressive interference;

The second removing unit is configured to perform adaptive filtering on the interference canceling signal, and then superimpose the adaptively filtered interference canceling signal on the signal, and remove suppressive interference in the signal;

The determination module specifically includes:

A first judging unit, configured to judge whether the power of the signal is within the power range, if not, the signal is deceptive interference, and the signal is discarded;

The second judging unit is used for judging whether the arrival time of the signal is a value within the arrival time range if it is a value within the power range, if not, the signal is deceptive interference, and the signal is discarded ;

The third judging unit is used to judge whether the arrival angle of the signal is a value within the arrival angle range if it is a value within the arrival time range, if not, the signal is deceptive interference, and discard the Signal;

The fourth judging unit is used for judging whether the navigation parameter of the signal is a value within the range of the navigation parameter if it is a value within the range of the arrival angle, if not, the signal is deceptive interference, and discarding the signal; if yes, said signal is a normal signal from a satellite.

The device also includes:

The receiving module is used to receive a plurality of signals, and the number of the signals is at least four; judge whether the signal-to-noise ratio of the signals exceeds a preset threshold; if the number of signals exceeding the threshold is at least four, the The signal that does not exceed the threshold is zeroed, and the direction of the signal that does not exceed the threshold is recorded; if the number of signals that exceed the threshold is less than four, all the signals are discarded, and the main antenna diagram is adjusted. Lobe gain, using the main lobe to re-receive the signal.

By adjusting the filter threshold and signal threshold according to the position of the receiving end and the change of the external environment, the narrowband suppressive interference can be removed through the filter threshold, the broadband suppressive interference can be removed by obtaining the interference cancellation signal, and whether the signal is deceptive interference can be determined through the signal threshold . In this way, without knowing the characteristics of the interference in advance, the interference can also be suppressed, and the suppressive interference of the broadband can be suppressed. The position of the receiving end and the change of the external environment can also be considered, and the deceptive interference can be effectively suppressed.

Description of drawings

FIG. 1 is a flowchart of a method for suppressing interference provided by Embodiment 1 of the present invention;

FIG. 2 is a flowchart of a method for suppressing interference provided by Embodiment 2 of the present invention;

Fig. 3 is a schematic diagram of a device for suppressing interference provided by Embodiment 3 of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the implementation manner of the present invention will be further described in detail below in conjunction with the accompanying drawings.

Example 1

As shown in Figure 1, an embodiment of the present invention provides a method for suppressing interference, including:

Step 101: Adjust the filtering threshold and signal threshold according to the location of the receiving end, the external environment and signal propagation error factors;

Among them, the location of the receiving end includes at least latitude and longitude and altitude, the external environment where the receiving end is located includes at least air humidity and surrounding obstacles, signal propagation error factors include at least ionospheric and tropospheric refraction, and the signal threshold that needs to be adjusted includes at least power range, Arrival Time Range, Arrival Angle Range, or Navigation Parameter Range.

Step 102: Determine the type of suppressed interference in the received signal, if the suppressed interference in the signal is narrowband type, then perform step 103: if the suppressed interference in the received signal is broadband type, then perform step 104:

Step 103: intercepting the received signal through a window function, and removing suppressive interference whose frequency spectrum exceeds the filtering threshold from the intercepted signal;

Step 104: Obtain an interference cancellation signal, and use the interference cancellation signal to remove suppressive interference from the received signal;

Step 105: According to the signal threshold, determine whether the received signal is fraudulent interference, if yes, perform step 106; if not, then the received signal is a normal signal, and the operation ends;

Step 106: The received signal is discarded, and the operation ends.

In the embodiment of the present invention, the filter threshold and signal threshold are adjusted according to the position of the receiving end, the external environment and the change of signal propagation error factors, and the narrowband suppressive interference is removed through the filter threshold, and the broadband suppressive interference is removed by obtaining an interference cancellation signal. Interference, determine whether the signal is deceptive interference through the signal threshold. In this way, without knowing the characteristics of the interference in advance, the interference can also be suppressed, and the suppressive interference of the broadband can be suppressed. The position of the receiving end and the change of the external environment can also be considered, and the deceptive interference can be effectively suppressed.

Example 2

As shown in Figure 2, an embodiment of the present invention provides a method for suppressing interference, including:

Step 201: According to the location of the receiving end and the external environment, as well as signal propagation error factors, adjust the signal threshold and filtering threshold stored in the knowledge base in the receiving end, wherein the signal threshold to be adjusted includes the power range and arrival time range , Arrival angle range or navigation parameter range;

Wherein, the location of the receiving end includes at least latitude and longitude and altitude, the external environment where the receiving end is located includes at least surrounding obstacles and/or air humidity of the receiving end, and signal propagation error factors include at least ionospheric and tropospheric refraction.

Wherein, the sensor of the receiving end monitors the position of the receiving end, the external environment and the signal propagation error factors in real time, and when the change of the position of the receiving end and/or the external environment and the signal propagation error factors is detected, this step is performed, specifically, According to changes in the ionosphere, tropospheric refraction and/or the altitude of the receiving end, adjust the size of the power range in the knowledge base; Adjust the size of the arrival time range in the knowledge base; adjust the size of the arrival angle range in the knowledge base according to the longitude, latitude and altitude of the receiving end, the change of ionosphere and troposphere refraction; according to the longitude and latitude, ionosphere, troposphere refraction and/or Or air humidity changes, adjust the size of the navigation parameter range; according to the ionosphere where the receiving end is located, tropospheric refraction, obstacles around the receiving end and/or changes in air humidity, adjust the size of the filter threshold.

Wherein, the different positions of the receiving end and the corresponding relationship between the external environment and the signal threshold are stored in the knowledge base in advance. For example, the corresponding relationship between the change range of the tropospheric refraction and the filtering threshold is set in advance in the knowledge base, as shown in Table 1, when the changing value of the tropospheric refraction is detected, the filter gate that needs to be adjusted is found from the corresponding relationship in Table 1 limit.

Table 1

Variation range of tropospheric refraction filter threshold [5-6) 2 [6-7) 3  …  …

Among them, the power, time of arrival, angle of arrival and navigation parameters obtained from the signal all change with the location of the receiving end or the external environment and the error factors of signal propagation. Therefore, adjusting the knowledge base according to the location of the receiving end and the external environment can accurately suppress interference and prevent the power, time of arrival, angle of arrival and navigation parameter mutations obtained from the signal in different occasions and emergencies, which cannot be effectively suppress interference.

Step 202: receiving a signal sent from a satellite;

Wherein, the received signal may be a signal mixed with a normal signal from a satellite and suppressed interference, or may be a signal mixed with suppressed interference and deceptive interference. The receiving end needs four different signals to position itself, so the number of received signals is at least four, and the number of satellites is also at least four. Antennas are used to receive signals sent by satellites, and each antenna receives at least one signal sent by satellites.

Step 203: Judging whether the signal-to-noise ratio of each signal exceeds a preset threshold, if the number of signals exceeding the threshold is at least four, then perform step 204; if the number of signals exceeding the threshold is less than four, then Execute step 205;'

Step 204: For signals that do not exceed the threshold, control the antenna to zero the signal, that is, do not receive signals that do not exceed the threshold, and only receive signals that exceed the threshold, and perform step 206;

Among them, if the signal-to-noise ratio in the signal does not exceed the threshold, it indicates that the signal is subject to strong suppressive interference, and the signal can be discarded by zeroing the antenna, and the direction of the signal can also be recorded in the knowledge base , the next time you use the antenna to receive signals, skip this direction directly.

Step 205: adjust the main lobe of each antenna pattern to align with the satellite, increase the gain of the main lobe pattern of the antenna pattern, and receive the signal from the satellite again through the main lobe of the antenna pattern;

Among them, the antenna diagram of the antenna includes a main lobe and multiple side lobes. After the main lobe of the antenna diagram receives the signal, the signal-to-noise ratio of the received signal can be improved by increasing the gain of the main lobe of the antenna diagram, that is, through the main lobe The signal-to-noise ratio of the re-received signal is improved.

Step 206: For one of the received signals, determine the type of suppressive interference in the received signal, if it is narrowband suppressive interference, perform step 207; if it is wideband suppressive interference, perform step 210;

Wherein, the number of received signals is at least four, and the processing process for each signal is the same, so for the convenience of description, one signal is taken as an example for description. In addition, the received signals are all time-domain signals.

Step 207: Select a window function according to the required resolution and signal frequency, and use the window function to intercept the received signal;

Among them, the resolution can be set in advance according to the needs. Specifically, the frequency of the signal and the resolution are calculated by the ratio calculation to obtain the window width, and then the corresponding main lobe width and main lobe difference are mapped out from the window width. Lobe width and main and side lobe difference, select the corresponding window function from the window functions stored in the knowledge base.

Wherein, the window function includes a main lobe and multiple side lobes, and the side lobes are divided into a first side lobe, a second side lobe, and the like. The width of the main lobe is the width of the main lobe, and the height difference between the main lobe and the first minor lobe is the difference between the main lobe and the first minor lobe.

Step 208: Carry out FFT (Fast Fourier Transform, Fast Fourier Transform) transformation to the intercepted signal to obtain a spectrum signal, and remove the suppressed interference signal whose spectrum exceeds the filtering threshold from the spectrum signal;

Wherein, for the normal signal from the satellite, most of the frequency spectrum obtained through FFT transformation will not exceed the filtering threshold value, therefore, the frequency spectrum of suppressing interference can be filtered out through the filtering threshold. In addition, it is possible to cancel part of the frequency spectrum of the normal signal by filtering the threshold.

Step 209: Obtain a reconstructed signal according to the trend and slope of the spectral line in the spectral signal from which suppressive interference has been removed, and use the reconstructed signal to compensate the spectral signal from which suppressive interference has been removed; perform IFFT (Inverse Fast Fourier Transform) on the compensated spectral signal , inverse Fourier transform) transform to obtain a time-domain signal, which is a signal for removing suppressive interference, and step 212 is performed;

Specifically, according to the trend and slope of the spectral line in the spectrum signal with suppressed interference removed, it is matched with the spectrum graph stored in the knowledge base to obtain a spectrum graph. The signal is linearly interpolated to obtain a reconstructed signal, and the reconstructed signal is used to compensate and remove the suppressed interference spectrum signal; the compensated spectrum signal is subjected to IFFT transformation to obtain a time domain signal.

Among them, a large number of spectrum diagrams of signal models are stored in the knowledge base in advance; firstly, the spectrum signals with suppressed interference are matched with the spectrum diagrams of each signal model in the knowledge base to match the most similar spectrum diagrams, and then refer to the The spectrogram performs linear interpolation on the spectral signal with suppressed interference removed to obtain the reconstructed signal. The reconstructed signal is a portion of the spectrum that is missing from the spectrum signal relative to the spectrum map from which suppressed interference has been removed.

Wherein, using the reconstructed signal to compensate and remove the spectral signal of suppressive interference specifically includes: reconstructing the reconstructed signal and the spectral signal from which suppressive interference has been removed.

In addition, use the window function obtained in step 207 to intercept the signal from the remaining signal in the received signal, and then remove the suppressive interference in the intercepted signal according to steps 208 and 209, so that the interception is repeated until the entire received signal is intercepted until the signal.

Step 210: From the received signal, extract characteristic parameters including variance, mean value, frequency and period, etc., and generate suppressive interference with the received signal by linearly matching the extracted characteristic parameters with the signal characteristics in the knowledge base related interference cancellation signals;

Furthermore, the generated interference cancellation signal can also be stored in the knowledge base, and when the same signal is received next time, the stored interference cancellation signal can be directly used to remove suppressive interference in the signal.

Step 211: Perform adaptive filtering on the interference canceling signal, and then superimpose the adaptively filtered interference canceling signal on the received signal to eliminate suppressive interference in the received signal;

Wherein, suppressive interference in the received signal has been suppressed at this time, and the signal may be a normal signal from a satellite at this time, or may be a deceptive interference signal. The next step is to judge whether the signal is a deceptive jamming signal.

Step 212: extract the power value of the received signal from the received signal, judge whether the extracted power belongs to the value within the power range stored in the knowledge base, if yes, then perform step 213; if not, then the signal is fraudulent interference, go to step 219;

Step 213: Obtain the arrival time of the signal from the received signal;

Specifically, a recurring code is generated according to the received signal, the number of chips offset between the received signal and the recurring code is calculated, and the arrival time is calculated according to the product of the number of chips and the chip interval.

Wherein, according to the received signal, the receiving end reproduces the chip sequence sent at the time of sending, which is the recurring code (this is the prior art, which is not limited in this embodiment). Both the chips in the received signal and the chips in the recurring code take 1023 chips as the cycle period, and there is a starting chip in each cycle, and the starting chip in the received signal The serial number is subtracted from the initial chip serial number of the recurring code to obtain the number of chips offset between the received signal and the recurring code.

Step 214: Judging whether the arrival time of the received signal belongs to the value within the arrival time range stored in the knowledge base, if yes, then execute step 215, if not, then execute step 219;

Wherein, the time-of-arrival value of spoofed interference exceeds the time-of-arrival range stored in the knowledge base, so if the time-of-arrival value of the received signal does not belong to the value within the time-of-arrival range, the received signal is spoofed interference.

Step 215: Extracting the angle of arrival from the received signal, wherein the angle of arrival is the angle between the line connecting the satellite and the receiving end and the horizontal plane;

Step 216: Judging whether the angle of arrival belongs to the value within the range of angles of arrival stored in the knowledge base, if yes, execute step 217; if not, execute step 219;

Wherein, the angle of arrival of the spoofed interference exceeds the range of the angle of arrival stored in the knowledge base, so if the angle of arrival of the received signal does not belong to a certain value within the range of the angle of arrival, the received signal is spoofed interference.

Step 217: Extract orbital radius and direction angle from received signal, wherein, orbital radius and direction angle form navigation parameter together, the connection line of satellite and receiving end projects straight line on horizontal plane, and this straight line is with X-axis or Y-axis in horizontal plane The included angle is the direction angle;

Step 218: Judging whether the navigation parameter belongs to a certain value within the range of navigation parameters stored in the knowledge base, if yes, the received signal is a normal signal from the satellite, and the operation ends, if not, execute step 219;

Wherein, the navigation parameter of the deceptive interference signal exceeds the navigation parameter range stored in the knowledge base, so the navigation parameter of the received signal does not belong to a certain value within the navigation parameter range, and the received signal is deceptive interference.

Step 219: The received signal is deceptive interference, the signal is directly discarded, and the operation ends.

Wherein, following steps 206-219 repeatedly, interference suppression is performed on the remaining received signals.

In the embodiment of the present invention, by adjusting the filter threshold and signal threshold according to the position of the receiving end and the change of the external environment, the narrowband suppressive interference is removed through the filter threshold, and the broadband suppressive interference is removed by obtaining an interference cancellation signal. Determine if the signal is spoofing jamming. In this way, without knowing the characteristics of the interference in advance, the interference can also be suppressed, and the suppressive interference of the broadband can be suppressed. The position of the receiving end and the change of the external environment can also be considered, and the deceptive interference can be effectively suppressed.

Example 3

As shown in Figure 3, an embodiment of the present invention provides a device for suppressing interference, including:

An adjustment module 301, configured to adjust the filtering threshold and the signal threshold according to the location of the receiving end, the external environment and signal propagation error factors;

The first removal module 302 is configured to intercept the signal by using a window function when the suppressive interference in the signal is of a narrowband type, and remove the suppressive interference whose spectrum exceeds the filtering threshold from the intercepted signal;

The second removal module 303 is configured to obtain an interference cancellation signal when the suppression interference in the signal is of a broadband type, and remove the suppression interference from the signal by using the interference cancellation signal;

The determination module 304 is configured to determine whether the signal is fraudulent interference according to the signal threshold, if yes, discard the signal, and if not, then the signal is a normal signal.

Among them, the location of the receiving end includes at least latitude and longitude and altitude, the external environment where the receiving end is located includes at least air humidity and surrounding obstacles, the signal propagation error factors include at least ionospheric and tropospheric refraction, and the signal threshold includes at least the power range and arrival time range , Arrival angle range or navigation parameter range;

Correspondingly, the adjustment module 301 specifically includes:

The first adjustment unit is configured to adjust the size of the power range according to changes in the ionosphere, tropospheric refraction and/or altitude;

The second adjustment unit is used to adjust the size of the arrival time range according to changes in latitude and longitude, altitude, ionosphere and/or tropospheric refraction:

The third adjustment unit is used to adjust the size of the arrival angle range according to changes in the ionosphere, tropospheric refraction, latitude and longitude and/or altitude;

A fourth adjustment unit, configured to adjust the size of the navigation parameter range according to changes in latitude and longitude, ionosphere, tropospheric refraction and/or air humidity;

The fifth adjustment unit is configured to adjust the size of the filtering threshold according to changes in the ionosphere, tropospheric refraction, surrounding obstacles and/or air humidity.

The first removal module 302 specifically includes:

An intercepting unit, configured to intercept the received signal through a window function, and perform FFT transformation on the intercepted signal to obtain a spectrum signal;

A first removing unit, configured to remove suppressive interference whose spectrum exceeds a filtering threshold from the spectrum signal;

The obtaining unit is used to match the stored spectrogram with the stored spectrogram according to the trend and slope of the spectral line in the spectral signal from which suppressive interference has been removed, and perform linear interpolation with the matched spectrogram as a reference to obtain the reconstructed signal;

a compensation unit, configured to use the obtained reconstructed signal to compensate and remove the spectral signal of suppressing interference;

A transformation unit, configured to perform IFFT transformation on the compensated spectrum signal to obtain a loaded signal;

The second removal module 303 specifically includes:

The extraction unit is used to extract characteristic parameters from the signal, and the characteristic parameters include at least variance, mean value, frequency and period;

The linear matching unit is used to perform linear matching with the stored signal characteristics through the characteristic parameters to generate an interference cancellation signal;

The second removing unit is configured to perform adaptive filtering on the interference canceling signal, and then superimpose the adaptively filtered interference canceling signal on the signal, so as to remove suppressive interference in the signal.

The determining module 304 specifically includes:

The first judging unit is used to judge whether the power of the signal is a value within the power range, if not, the signal is deceptive interference, and the signal is discarded;

The second judging unit is used to judge whether the arrival time of the signal is a value within the arrival time range if it is a value within the power range, if not, the signal is deceptive interference, and the signal is discarded;

The third judging unit is used to determine whether the angle of arrival of the signal is a value within the range of the arrival angle if it is a value within the arrival time range, if not, the signal is deceptive interference, and the signal is discarded;

The fourth judging unit is used to judge whether the navigation parameter of the signal is a value within the range of the navigation parameter if it is a value within the range of the angle of arrival, if not, the signal is deceptive interference, and the signal is discarded; if yes, the signal is from a satellite normal signal;

Further, the device for suppressing interference also includes:

The receiving module is used to receive multiple signals, and the received signals are at least four; judge whether the signal-to-noise ratio of each signal exceeds a preset threshold; if the number of signals exceeding the threshold is at least four, the Zero the signals that exceed the threshold, and record the direction of the signals that do not exceed the threshold; if the number of signals that exceed the threshold is less than four, discard all received signals and adjust the gain of the main lobe of the antenna diagram, Use the main lobe to re-receive the signal.

In the embodiment of the present invention, by adjusting the filter threshold and signal threshold according to the position of the receiving end and the change of the external environment, the narrowband suppressive interference is removed through the filter threshold, and the broadband suppressive interference is removed by obtaining an interference cancellation signal. Determine if the signal is spoofing jamming. In this way, without knowing the characteristics of the interference in advance, the interference can also be suppressed, and the suppressive interference of the broadband can be suppressed. The position of the receiving end and the change of the external environment can also be considered, and the deceptive interference can be effectively suppressed.

All or part of the technical solutions provided by the above embodiments can be realized by software programming, and the software program is stored in a readable storage medium, such as a hard disk, an optical disk or a floppy disk in a computer.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within range.

Claims (9)

1. suppress a method of disturbing, it is characterized in that, described method comprises:

According to the position at receiving terminal place and external environment and signal propagation errors factor, adjust filter threshold and signal threshold value;

Pressing type in signal disturbs as arrowband type, by window function, intercepts described signal, removes the pressing type interference that frequency spectrum surpasses described filter threshold from the signal of described intercepting;

Pressing type in described signal disturbs as wide-band type, obtains interference-cancelled signals, and utilizes described interference-cancelled signals from described signal, to remove pressing type and disturb;

According to described signal threshold value, determine whether described signal is that deception formula is disturbed, and if so, abandons described signal, and if not, described signal is normal signal;

Wherein, describedly by window function, intercept described signal, from the signal of described intercepting, remove the pressing type that frequency spectrum surpasses described filter threshold and disturb, specifically comprise:

By described window function, intercept described signal, and the signal of described intercepting is carried out to fast fourier transform obtain spectrum signal;

From described spectrum signal, remove frequency spectrum over the pressing type interference of described filter threshold;

In the spectrum signal disturbing according to described removal pressing type, trend and the slope of spectral line, match a spectrogram with the spectrogram of having stored, and take the spectrogram of described coupling as with reference to carrying out linear interpolation, obtains reconstruction signal;

Utilize described reconstruction signal to compensate the spectrum signal that described removal pressing type disturbs;

The spectrum signal of described compensation is carried out to inverse Fourier transform, obtain the signal of described intercepting.

2. the method for claim 1, it is characterized in that, the position at described receiving terminal place at least comprises longitude and latitude and height above sea level, the external environment at described receiving terminal place at least comprises air humidity and obstacle around, described signal propagation errors factor at least comprises ionosphere and tropospheric refraction, and described signal threshold value at least comprises power bracket, time of advent scope, arrives angular range or navigational parameter scope;

Correspondingly, described according to the position at receiving terminal place and external environment and signal propagation errors factor, adjust filter threshold and signal threshold value, specifically comprise:

According to the variation of described ionosphere, described tropospheric refraction and/or described height above sea level, adjust the size of described power bracket;

According to the variation of described longitude and latitude, described height above sea level, described ionosphere and/or described tropospheric refraction, adjust the size of described time of advent of scope;

According to the variation of described ionosphere, described tropospheric refraction, described longitude and latitude and/or described height above sea level, adjust the size of described arrival angular range;

According to the variation of described longitude and latitude, described ionosphere, described tropospheric refraction and/or described air humidity, adjust the size of described navigational parameter scope;

According to the variation of described ionosphere, described tropospheric refraction, described peripheral obstacle and/or described air humidity, adjust the size of described filter threshold.

3. the method for claim 1, is characterized in that, described in obtain interference-cancelled signals, and utilize described interference-cancelled signals from described signal, to remove pressing type and disturb, specifically comprise:

From described signal, extract characteristic parameter, described characteristic parameter at least comprises variance, average, frequency and cycle;

By described characteristic parameter and the signal characteristic of having stored, carry out linear matched, produce and disturb relevant interference-cancelled signals to described pressing type;

Described interference-cancelled signals is carried out to adaptive-filtering, the more described interference-cancelled signals after adaptive-filtering is added in described signal, the pressing type of removing in described signal disturbs.

4. the method for claim 1, is characterized in that, described according to described signal threshold value, determines whether described signal is that deception formula is disturbed, and if so, abandons described signal, and if not, described signal is normal signal, specifically comprises:

Whether the power that judges described signal is the value in described power bracket, and if not, described signal is that deception formula is disturbed, and abandons described signal;

If the value in described power bracket judges whether is the value within the scope of the described time of advent time of advent of described signal, if not, described signal is that deception formula is disturbed, and abandons described signal;

If the value within the scope of the described time of advent judges whether the arrival angle of described signal is the value in described arrival angular range, if not, described signal is that deception formula is disturbed, and abandons described signal;

If the value in described arrival angular range judges whether the navigational parameter of described signal is the value within the scope of described navigational parameter, if not, described signal is that deception formula is disturbed, and abandons described signal; If so, described signal is the normal signal from satellite.

5. method as claimed in claim 2, is characterized in that, described according to the position at receiving terminal place and external environment and signal propagation errors factor, after adjusting filter threshold and signal threshold value, also comprises:

Receive a plurality of signals, described signal is at least four;

Whether the signal to noise ratio that judges described signal surpasses default threshold value;

If surpass the number of the signal of described threshold value, be at least four, will not surpass the signal balancing of described threshold value, and record do not surpass the direction of the signal of described threshold value;

If surpass the number of the signal of described threshold value, be less than four, abandon all described signals, adjust the gain of the main lobe of antenna diagram, utilize described main lobe again to receive signal.

6. suppress the equipment disturbing, it is characterized in that, described equipment comprises:

Adjusting module, for according to the position at receiving terminal place and external environment and signal propagation errors factor, adjusts filter threshold and signal threshold value;

The first removal module, disturbs as arrowband type for the pressing type when signal, by window function, intercepts described signal, removes the pressing type interference that frequency spectrum surpasses described filter threshold from the signal of described intercepting;

Second removes module, for the pressing type when described signal, disturbs as wide-band type, obtains interference-cancelled signals, and utilizes described interference-cancelled signals from described signal, to remove pressing type and disturb;

Determination module, for according to described signal threshold value, determines whether described signal is that deception formula is disturbed, and if so, abandons described signal, and if not, described signal is normal signal;

Described first removes module specifically comprises:

Interception unit, for intercepting described signal by described window function, and carries out fast fourier transform to the signal of described intercepting and obtains spectrum signal;

The first removal unit, the pressing type that surpasses described filter threshold for remove frequency spectrum from described spectrum signal disturbs;

Obtain unit, trend and slope for the spectrum signal spectral line that disturbs according to described removal pressing type, match a spectrogram with the spectrogram of having stored, and take the spectrogram of described coupling as with reference to carrying out linear interpolation, obtains reconstruction signal;

Compensating unit, for utilizing described reconstruction signal to compensate the spectrum signal that described removal pressing type disturbs;

Converter unit, for the spectrum signal of described compensation is carried out to inverse Fourier transform, obtains the signal of described intercepting.

7. equipment as claimed in claim 6, it is characterized in that, the position at described receiving terminal place at least comprises longitude and latitude and height above sea level, the external environment at described receiving terminal place at least comprises air humidity and obstacle around, described signal propagation errors factor at least comprises ionosphere and tropospheric refraction, and described signal threshold value at least comprises power bracket, time of advent scope, arrives angular range or navigational parameter scope;

Correspondingly, described adjusting module specifically comprises:

The first adjustment unit, for according to the variation of described ionosphere, described tropospheric refraction and/or described height above sea level, adjusts the size of described power bracket;

The second adjustment unit, for according to the variation of described longitude and latitude, described height above sea level, described ionosphere and/or described tropospheric refraction, adjusts the size of described time of advent of scope;

The 3rd adjustment unit, for according to the variation of described ionosphere, described tropospheric refraction, described longitude and latitude and/or described height above sea level, adjusts the size of described arrival angular range;

The 4th adjustment unit, for according to the variation of described longitude and latitude, described ionosphere, described tropospheric refraction and/or described air humidity, adjusts the size of described navigational parameter scope;

The 5th adjustment unit, for according to the variation of described ionosphere, described tropospheric refraction, described peripheral obstacle and/or described air humidity, adjusts the size of described filter threshold.

8. equipment as claimed in claim 6, is characterized in that, described second removes module specifically comprises:

Extraction unit, for extracting characteristic parameter from described signal, described characteristic parameter at least comprises variance, average, frequency and cycle; ,

Linear matched unit, for carrying out linear matched by described characteristic parameter and the signal characteristic of having stored, produces and disturbs relevant interference-cancelled signals to described pressing type;

The second removal unit, for described interference-cancelled signals is carried out to adaptive-filtering, then is added to the described interference-cancelled signals after adaptive-filtering in described signal, and the pressing type of removing in described signal disturbs;

Described determination module specifically comprises:

The first judging unit, for judging whether the power of described signal is the value in described power bracket, if not, described signal is that deception formula is disturbed, and abandons described signal;

The second judging unit, for if the value in described power bracket judges whether is the value within the scope of the described time of advent time of advent of described signal, if not, described signal is that deception formula is disturbed, and abandons described signal;

The 3rd judging unit, for if the value within the scope of the described time of advent judges whether the arrival angle of described signal is the value in described arrival angular range, if not, described signal is that deception formula is disturbed, and abandons described signal;

The 4th judging unit, for if the value in described arrival angular range judges whether the navigational parameter of described signal is the value within the scope of described navigational parameter, if not, described signal is that deception formula is disturbed, and abandons described signal; If so, described signal is the normal signal from satellite.

9. equipment as claimed in claim 6, is characterized in that, described equipment also comprises:

Receiver module, for receiving a plurality of signals, described signal is at least four; Whether the signal to noise ratio that judges described signal surpasses default threshold value; If surpass the number of the signal of described threshold value, be at least four, will not surpass the signal balancing of described threshold value, and record do not surpass the direction of the signal of described threshold value; If surpass the number of the signal of described threshold value, be less than four, abandon all described signals, adjust the gain of the main lobe of antenna diagram, utilize described main lobe again to receive signal.

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