An interference suppression method and device based on a single-aperture dual-polarized antenna

Abstract

The application provides a single-aperture dual-polarized antenna-based interference suppression method and device, which comprises the following steps: receiving RHCR signal components and LHCR signal components in electromagnetic waves through a single-aperture dual-polarized antenna; determining an output signal of the single-aperture dual-polarized antenna based on the RHCR signal components, the LHCR signal components and a phase value of a phase shifter; acquiring and tracking GNSS signals to obtain a phase-locked loop state according to the output signal, and determining a carrier-to-noise ratio estimation result according to the output signal; updating the phase value of the phase shifter based on the phase-locked loop state and the carrier-to-noise ratio estimation result, and executing the step of determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal components, the LHCR signal components and the phase value of the phase shifter. The GNSS interference suppression capability, especially the wideband interference suppression capability, can be improved without increasing the size, power consumption and weight of the GNSS receiver.

Description

Technical Field

[0001] This invention relates to the field of satellite navigation technology, specifically to an interference suppression method and apparatus based on a single-aperture dual-polarized antenna. Background Technology

[0002] With the rapid growth of the drone market, Global Navigation Satellite System (GNSS) positioning devices are being installed on drones to provide them with orientation, navigation, and timing services. However, electromagnetic interference to the GNSS positioning device on a drone can cause it to make an emergency landing or even crash, making it necessary to improve the anti-interference capabilities of GNSS receivers.

[0003] Current GNSS anti-jamming technologies mainly rely on space-time / space-frequency joint anti-jamming technology. However, this technology depends on array antennas, which greatly increases the size, power consumption, and weight of GNSS receivers, thus limiting their application in UAVs. The aforementioned anti-jamming technologies have significant limitations. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide an interference suppression method and apparatus based on a single-aperture dual-polarized antenna to solve the problems of significant limitations in existing anti-interference technologies.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0006] The first aspect of this invention discloses an interference suppression method based on a single-aperture dual-polarized antenna, the method being applied to a UAV, the method comprising:

[0007] The right-hand circularly polarized (RHCR) signal component and the left-hand circularly polarized (LHCR) signal component in electromagnetic waves are received by a single-aperture dual-polarized antenna.

[0008] The output signal of the single-aperture dual-polarized antenna is determined based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter.

[0009] The phase-locked loop state is obtained by capturing and tracking GNSS signals of the Global Navigation Satellite System based on the output signal, and the carrier-to-noise ratio estimation result is determined based on the output signal.

[0010] Based on the phase-locked loop state and the carrier-to-noise ratio estimation result, the phase value of the phase shifter is updated, and the step of determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component and the phase value of the phase shifter is performed.

[0011] Preferably, determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter includes:

[0012] The RHCR signal component is phase-shifted using the phase value of a phase shifter;

[0013] The LHCR signal component and the phase-shifted RHCR signal component are combined to obtain the output signal of the single-aperture dual-polarized antenna.

[0014] Preferably, the step of updating the phase value of the phase shifter based on the phase-locked loop state and the carrier-to-noise ratio estimation result, and determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter, includes:

[0015] When the phase-locked loop is in a locked state, the phase value of the phase shifter is increased according to a preset increment formula, and the step of determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component and the phase value of the phase shifter is performed.

[0016] Obtain the carrier-to-noise ratio (CNR) estimation results before the phase value is increased and the CNR estimation results after the phase value is increased;

[0017] When the carrier-to-noise ratio (CNR) estimation result after the phase value increases is less than the CNR estimation result before the phase value increases, the counter value is incremented by 1;

[0018] If the value of the counter is less than the threshold, the step of increasing the phase value of the phase shifter according to the increment formula is executed when the phase-locked loop is in a locked state.

[0019] If the value of the counter is equal to the threshold, the value of the counter is cleared to zero, the phase value of the phase shifter is reduced according to a preset decreasing formula, and the step of determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component and the phase value of the phase shifter is executed.

[0020] Obtain the carrier-to-noise ratio (CNR) estimation result before the phase value decreases and the CNR estimation result after the phase value decreases;

[0021] When the carrier-to-noise ratio (CNR) estimation result after the phase value decreases is less than the CNR estimation result before the phase value decreases, the value of the counter is incremented by 1;

[0022] If the value of the counter is less than the threshold, the step of decreasing the phase value of the phase shifter according to a preset decreasing formula is executed;

[0023] If the value of the counter is equal to the threshold, the value of the counter is cleared to zero, and the step of increasing the phase value of the phase shifter according to a preset increment formula is executed when the phase-locked loop is in a locked state.

[0024] Preferably, the method further includes:

[0025] When the estimated carrier-to-noise ratio after the phase value increases is not less than the estimated carrier-to-noise ratio before the phase value increases, the value of the counter is cleared to zero, and the step of increasing the phase value of the phase shifter according to the increment formula is executed when the phase-locked loop is in a locked state.

[0026] If the estimated carrier-to-noise ratio after the phase value decreases is not less than the estimated carrier-to-noise ratio before the phase value decreases, the value of the counter is cleared to zero, and the step of decreasing the phase value of the phase shifter according to the preset decreasing formula is executed.

[0027] Preferably, the method further includes:

[0028] When the phase-locked loop is in an unlocked state, the phase value of the phase shifter is increased according to the increment formula, and the step of determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component and the phase value of the phase shifter is performed until the phase-locked loop changes to a locked state.

[0029] A second aspect of this invention discloses an interference suppression device based on a single-aperture dual-polarized antenna, the device being applied to a drone, the device comprising:

[0030] The receiving unit is used to receive the right-hand circularly polarized (RHCR) signal component and the left-hand circularly polarized (LHCR) signal component in electromagnetic waves through a single-aperture dual-polarized antenna.

[0031] The determining unit is used to determine the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter;

[0032] The processing unit is used to acquire and track the GNSS signal of the Global Navigation Satellite System according to the output signal to obtain the phase-locked loop state, and to determine the carrier-to-noise ratio estimation result according to the output signal;

[0033] The update unit is used to update the phase value of the phase shifter based on the phase-locked loop state and the carrier-to-noise ratio estimation result, and to execute the determination unit.

[0034] Preferably, the determining unit is specifically used to: shift the phase of the RHCR signal component using the phase value of the phase shifter; and combine the LHCR signal component and the phase-shifted RHCR signal component to obtain the output signal of the single-aperture dual-polarized antenna.

[0035] Preferably, the update unit includes:

[0036] An increment module is used to increase the phase value of the phase shifter according to a preset increment formula when the phase-locked loop is in a locked state, and to execute the determination unit.

[0037] The first acquisition module is used to acquire the carrier-to-noise ratio estimation result before the phase value is increased and the carrier-to-noise ratio estimation result after the phase value is increased;

[0038] The first processing module is configured to increment a counter by 1 when the estimated carrier-to-noise ratio after the phase value increases is less than the estimated carrier-to-noise ratio before the phase value increases; execute the increment module if the value of the counter is less than a threshold; and clear the value of the counter to zero and execute the decrement module if the value of the counter is equal to the threshold.

[0039] The decreasing module is used to decrease the phase value of the phase shifter according to a preset decreasing formula and execute the determining unit;

[0040] The second acquisition module is used to acquire the carrier-to-noise ratio estimation result before the phase value decreases and the carrier-to-noise ratio estimation result after the phase value decreases;

[0041] The second processing module is used to increment the value of the counter by 1 when the estimated carrier-to-noise ratio after the phase value decreases is less than the estimated carrier-to-noise ratio before the phase value decreases; if the value of the counter is less than the threshold, execute the decrement module; if the value of the counter is equal to the threshold, clear the value of the counter to zero and execute the increment module.

[0042] Preferably, the update unit further includes:

[0043] The third processing module is used to clear the value of the counter and execute the increment module when the carrier-to-noise ratio estimation result after the phase value increases is not less than the carrier-to-noise ratio estimation result before the phase value increases.

[0044] The fourth processing module is used to clear the value of the counter and execute the decrementing module when the estimated carrier-to-noise ratio after the phase value decreases is not less than the estimated carrier-to-noise ratio before the phase value decreases.

[0045] Preferably, the update unit further includes:

[0046] The update module is used to increase the phase value of the phase shifter according to the increment formula when the phase-locked loop is in an unlocked state, and execute the determination unit until the phase-locked loop changes to a locked state.

[0047] The present invention provides an interference suppression method and apparatus based on a single-aperture dual-polarized antenna. The method comprises: receiving the RHCR and LHCR signal components from electromagnetic waves using a single-aperture dual-polarized antenna; determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal components, LHCR signal components, and the phase value of the phase shifter; acquiring and tracking GNSS signals according to the output signal to obtain the phase-locked loop (PLL) state, and determining the carrier-to-noise ratio (CNR) estimation result based on the output signal; updating the phase value of the phase shifter based on the PLL state and the CNR estimation result; and performing the step of determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal components, LHCR signal components, and the phase value of the phase shifter. This solution uses a small, single-array antenna, a single-aperture dual-polarized antenna, to suppress GNSS interference. Without increasing the size, power consumption, or weight of the GNSS receiver, it can improve the suppression capability of GNSS interference, especially broadband interference. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0049] Figure 1 A flowchart illustrating an interference suppression method based on a single-aperture dual-polarized antenna, provided for an embodiment of the present invention;

[0050] Figure 2 A flowchart for updating the phase value of a phase shifter provided in an embodiment of the present invention;

[0051] Figure 3 This is a schematic diagram illustrating the implementation principle of the interference suppression method based on a single-aperture dual-polarized antenna provided in an embodiment of the present invention.

[0052] Figure 4 This is a structural block diagram of an interference suppression device based on a single-aperture dual-polarized antenna, provided for an embodiment of the present invention. Detailed Implementation

[0053] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] In this application, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0055] As can be seen from the background technology, the current GNSS anti-jamming technology is mainly the space-time / space-frequency joint anti-jamming technology. However, the space-time / space-frequency joint anti-jamming technology relies on array antennas, which greatly increases the size, power consumption and weight of the GNSS receiver, thus limiting the application of GNSS receivers on UAVs. The aforementioned anti-jamming technology has significant limitations.

[0056] Therefore, embodiments of the present invention provide an interference suppression method and apparatus based on a single-aperture dual-polarized antenna. This method uses a small single-array antenna, a single-aperture dual-polarized antenna, to suppress GNSS interference. Without increasing the size, power consumption, and weight of the GNSS receiver, it can improve the suppression capability of GNSS interference, especially broadband interference.

[0057] The inventors discovered that, to achieve matched reception of GNSS signals, GNSS receiver antennas are generally designed with right-hand circularly polarized (RHCP) antennas. This ensures high RHCP gain and very low left-hand circularly polarized (LHCP) gain at high elevation angles. However, due to antenna design and manufacturing errors, the difference between RHCP and LHCP gains at low elevation angles is not significant. For aerial applications such as UAVs, electromagnetic interference near the ground typically reaches the GNSS receiver antenna from low and negative elevation angles. In these cases, the RHCP energy and LHCP energy of the electromagnetic interference received by the GNSS receiver antenna are roughly equal. Therefore, this scheme employs a single-aperture dual-polarized antenna to simultaneously receive the right-hand circularly polarized signal component (RHCR signal component) and the left-hand circularly polarized signal component (LHCR signal component) in electromagnetic waves. Through a corresponding feedback control method, it adaptively achieves the reverse cancellation of the RHCR signal component and the LHCR signal component, thereby suppressing electromagnetic interference. The following describes this scheme in detail through various embodiments.

[0058] See Figure 1 The diagram illustrates a flowchart of an interference suppression method based on a single-aperture dual-polarized antenna provided by an embodiment of the present invention. This interference suppression method is applied to a UAV and includes:

[0059] Step S101: Receive the RHCR and LHCR signal components in the electromagnetic waves using a single-aperture dual-polarized antenna.

[0060] In the specific implementation step S101, the RHCR signal component and LHCR signal component in the electromagnetic wave are simultaneously received by a single-aperture dual-polarized antenna. The received RHCR signal component is denoted as x. R (t), the received LHCR signal component is denoted as x. L (t).

[0061] Step S102: Determine the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter.

[0062] In the specific implementation step S102, the phase value of the phase shifter (programmable phase shifter) is used to shift the phase of the RHCR signal component; the LHCR signal component and the phase-shifted RHCR signal component are combined to obtain the output signal of the single-aperture dual-polarized antenna.

[0063] In other words, by phase-shifting the RHCR signal component with the LHCR signal component, the output signal of the single-aperture dual-polarized antenna can be obtained. The output signal of the single-aperture dual-polarized antenna is denoted as x(t). For details on the specific content of the output signal of the single-aperture dual-polarized antenna denoted as x(t), please refer to formula (1).

[0064]

[0065] In formula (1), The phase value of the phase shifter. The unit is degrees. The value range is from 0 to 360.

[0066] Step S103: Acquire and track the GNSS signal based on the output signal to obtain the phase-locked loop state, and determine the carrier-to-noise ratio estimation result based on the output signal.

[0067] In the specific implementation step S103, after obtaining the output signal of the single-aperture dual-polarized antenna, the GNSS signal is acquired and tracked using the output signal to obtain the phase-locked loop state; and the carrier-to-noise ratio (CNR) estimation result is determined based on the output signal. Specifically, a GNSS receiving unit can be used to receive the output signal of the single-aperture dual-polarized antenna. The GNSS receiving unit acquires and tracks the GNSS signal using the output signal to obtain the CNR state and determine the CNR estimation result.

[0068] It should be noted that GNSS signal acquisition is achieved through a two-dimensional search of the Doppler frequency and pseudocode phase. Two-dimensional searches mainly include linear search, parallel frequency search, and parallel code phase search. GNSS signal tracking is achieved through a tracking loop, which performs accurate estimation of the Doppler frequency and pseudocode phase. The carrier-to-noise ratio (CNR) estimation result is obtained by performing mathematical operations on the correlation values ​​output by the tracking loop.

[0069] More specifically, GNSS signal tracking is achieved through a phase-locked loop (PLL). The PLL state indicates whether the GNSS signal has been tracked. When the GNSS receiver unit successfully tracks the GNSS signal, the PLL is in a locked state; when the GNSS receiver unit fails to track the GNSS signal, the PLL is in an unlocked state.

[0070] It should be noted that the carrier-to-noise ratio (CNR) estimation results can be output at a frequency of 10Hz (this is just an example and can be adjusted according to the actual situation). The output frequency of the CNR estimation results is 10Hz, that is, the CNR estimation results are output once every 100ms. The unit of the CNR estimation results is dBHz.

[0071] Step S104: Based on the phase-locked loop state and carrier-to-noise ratio estimation results, update the phase value of the phase shifter and execute step S102.

[0072] In the specific implementation of step S104, the phase value of the phase shifter is updated based on the phase-locked loop state and the carrier-to-noise ratio estimation result; after updating the phase value of the phase shifter, steps S102 to S103 are executed to continue to determine the phase-locked loop state and the carrier-to-noise ratio estimation result, and then the phase value of the phase shifter is updated.

[0073] In this embodiment of the invention, a small single-array antenna with a single aperture dual polarization antenna is used to suppress GNSS interference. Without increasing the size, power consumption and weight of the GNSS receiver, the ability to suppress GNSS interference, especially broadband interference, can be improved.

[0074] The above embodiments of the present invention Figure 1 For details regarding updating the phase value of the phase shifter in step S104, please refer to [link / reference needed]. Figure 2 The flowchart illustrating the phase value update of the phase shifter provided in an embodiment of the present invention is shown. Figure 2 Includes the following steps:

[0075] Step S201: When the phase-locked loop is in a locked state, increase the phase value of the phase shifter according to the preset increment formula, and execute step S102.

[0076] In the specific implementation of step S201, when the phase-locked loop is in a locked state, the phase value of the phase shifter is increased according to a preset increment formula; after the phase value is increased (equivalent to updating the phase value), steps S102 to S103 are executed to determine the new phase-locked loop state and the new carrier-to-noise ratio estimation result.

[0077] In some specific embodiments, the details of the increment formula are shown in formula (2).

[0078]

[0079] In formula (2), The phase value of the phase shifter before the update. The phase value of the updated phase shifter is Δ, which is the iteration step. The smaller the iteration step Δ, the finer the control but the slower the convergence. The iteration step Δ can generally be taken as an empirical value of 1 (in degrees). It is worth noting that the phase value of the phase shifter is in the range of 0 to 360. The mod operation in formula (2) ensures that the phase value will not exceed the range of "0-360". mod(x,y) represents the remainder after x is divided by y.

[0080] Step S202: Obtain the carrier-to-noise ratio (CNR) estimation results before the phase value is increased and the CNR estimation results after the phase value is increased.

[0081] During the specific execution of step S202, the phase value of the phase shifter is increased according to the incremental formula, and after executing steps S102 to S103 to determine the new carrier-to-noise ratio (CNR) estimation result, the CNR estimation result before the phase value is increased and the CNR estimation result after the phase value is increased are obtained (or read).

[0082] Specifically, the carrier-to-noise ratio (CNR) estimate before the phase value is increased refers to the CNR estimate obtained before the phase value of the phase shifter is increased (or the phase value is updated). The CNR estimate after the phase value is increased refers to the new CNR estimate obtained after the phase value of the phase shifter is increased (or the phase value is updated).

[0083] Determine the relationship between the carrier-to-noise ratio (CNR) estimation results before and after the phase value is increased.

[0084] If the carrier-to-noise ratio (CNR) estimation result after the phase value increases is not less than the CNR estimation result before the phase value increases, proceed to step S203. If the CNR estimation result after the phase value increases is less than the CNR estimation result before the phase value increases, proceed to step S204 and subsequent related steps.

[0085] Step S203: When the carrier-to-noise ratio estimation result after the phase value increases is not less than the carrier-to-noise ratio estimation result before the phase value increases, clear the value of the counter to zero and execute step S201.

[0086] In the specific implementation of step S203, when the carrier-to-noise ratio estimation result after the phase value increases is not less than the carrier-to-noise ratio estimation result before the phase value increases, the value of the counter is cleared to zero, and step S201 is executed to continue increasing the phase value of the phase shifter according to the increment formula while the phase-locked loop is in the locked state.

[0087] Step S204: When the carrier-to-noise ratio estimation result after the phase value increases is less than the carrier-to-noise ratio estimation result before the phase value increases, the counter value is incremented by 1.

[0088] In the specific implementation of step S204, when the carrier-to-noise ratio estimation result after the phase value increases is less than the carrier-to-noise ratio estimation result before the phase value increases, the counter value is incremented by 1, and step S205 is executed.

[0089] Step S205: Determine if the timer value is equal to the threshold. If the counter value is less than the threshold, proceed to step S201. If the counter value is equal to the threshold, proceed to step S206.

[0090] In the specific implementation of step S205, it is determined whether the value of the timer is equal to the threshold K, which is a positive integer and can be an empirical value (e.g., K is 5). If the value of the counter is less than the threshold, step S201 is executed; if the value of the counter is equal to the threshold, step S206 is executed.

[0091] Step S206: Clear the counter value to zero.

[0092] Step S207: Decrease the phase value of the phase shifter according to the preset decreasing formula, and execute step S102.

[0093] In the specific implementation of step S207, the phase value of the phase shifter is reduced according to the preset decreasing formula (equivalent to changing the direction of the increase or decrease of the phase value of the phase shifter). After the phase value is reduced (equivalent to updating the phase value), steps S102 to S103 are executed to determine the new phase-locked loop state and the new carrier-to-noise ratio estimation result.

[0094] In some specific embodiments, the details of the decreasing formula can be found in formula (3).

[0095]

[0096] It should be noted that the meaning of the parameters in formula (3) can be found in the relevant content of formula (2), and will not be repeated here.

[0097] It should be further noted that the execution order of steps S206 and S207 is only for illustrative purposes; step S207 can also be executed first and then step S206. The execution order of steps S206 and S207 is not limited here.

[0098] Step S208: Obtain the carrier-to-noise ratio (CNR) estimation results before the phase value is reduced and the CNR estimation results after the phase value is reduced.

[0099] In the specific implementation of step S208, the phase value of the phase shifter is reduced according to the decreasing formula, and after steps S102 to S103 are executed to determine the new carrier-to-noise ratio (CNR) estimation result, the CNR estimation result before the phase value is reduced and the CNR estimation result after the phase value is reduced are obtained (or read).

[0100] Specifically, the carrier-to-noise ratio (CNR) estimate before the phase value is reduced refers to the CNR estimate obtained before the phase value of the phase shifter is reduced (or the phase value is updated). The CNR estimate after the phase value is reduced refers to the new CNR estimate obtained after the phase value of the phase shifter is reduced (or the phase value is updated).

[0101] Determine the relationship between the carrier-to-noise ratio (CNR) estimation results before the phase value decreases and the CNR estimation results after the phase value decreases.

[0102] If the carrier-to-noise ratio (CNR) estimation result after the phase value decreases is not less than the CNR estimation result before the phase value decreases, proceed to step S209. If the CNR estimation result after the phase value decreases is less than the CNR estimation result before the phase value decreases, proceed to step S210 and subsequent related steps.

[0103] Step S209: When the carrier-to-noise ratio estimation result after the phase value decreases is not less than the carrier-to-noise ratio estimation result before the phase value decreases, clear the value of the counter to zero and execute step S207.

[0104] In the specific implementation of step S209, when the estimated carrier-to-noise ratio after the phase value decreases is not less than the estimated carrier-to-noise ratio before the phase value decreases, the value of the counter is cleared to zero, and step S207 is executed to continue to decrease the phase value of the phase shifter according to the decreasing formula.

[0105] Step S210: When the carrier-to-noise ratio estimation result after the phase value decreases is less than the carrier-to-noise ratio estimation result before the phase value decreases, the counter value is incremented by 1.

[0106] In the specific implementation of step S210, when the carrier-to-noise ratio estimation result after the phase value decreases is less than the carrier-to-noise ratio estimation result before the phase value decreases, the counter value is incremented by 1, and step S211 is executed.

[0107] Step S211: Determine if the timer value is equal to the threshold. If the counter value is less than the threshold, proceed to step S207. If the counter value is equal to the threshold, proceed to step S212.

[0108] In the specific implementation of step S211, it is determined whether the value of the timer is equal to the threshold K, which is a positive integer and can be an empirical value (e.g., K is 5). If the value of the counter is less than the threshold, step S207 is executed; if the value of the counter is equal to the threshold, step S212 is executed.

[0109] Step S212: Clear the counter value and proceed to step S201.

[0110] In the specific implementation of step S212, the value of the counter is cleared to zero, and step S201 is executed to increase the phase value of the phase shifter according to the increment formula (which is also equivalent to changing the direction of increase or decrease of the phase value of the phase shifter).

[0111] During the execution of steps S201 to S212, the phase-locked loop (PLL) may be in an unlocked state. In some specific embodiments, when the PLL is in an unlocked state, the phase value of the phase shifter is increased according to the increment formula, and step S102 is executed until the PLL changes to a locked state.

[0112] More specifically, when the phase-locked loop (PLL) is in an unlocked state, the phase value of the phase shifter is increased according to an incremental formula, and steps S102 to S103 are executed to continue determining the PLL state and the carrier-to-noise ratio (CNR) estimation result until the PLL state changes to a locked state. It should be noted that the update period of the phase shifter's phase value is consistent with the output frequency of the CNR estimation result.

[0113] To better explain the contents of steps S201 to S212 above, the following processes A1 to A3 will be used to explain how to iterate and update the phase value of the phase shifter based on the carrier-to-noise ratio estimation result and phase-locked loop state output by the GNSS receiving unit.

[0114] A1. Upon power-on, initialize the phase value of the phase shifter. The initial value of the phase value is set to... (Generally, the value can be 0).

[0115] A2. Read the phase-locked loop (PLL) status. If the PLL status is unlocked, the phase value of the phase shifter is continuously increased according to the increment formula given in formula (2) until the PLL status changes to locked.

[0116] It should be noted that the update period of the phase shifter's phase value is consistent with the output frequency of the carrier-to-noise ratio estimation result.

[0117] When the phase-locked loop is in a locked state, execute A3.

[0118] A3. When the phase-locked loop is in a locked state, continue to increase the phase value of the phase shifter according to the increment formula given in formula (2); read the carrier-to-noise ratio estimation results before and after the update (such as the carrier-to-noise ratio estimation results before the phase value is increased and the carrier-to-noise ratio estimation results after the phase value is increased).

[0119] If the carrier-to-noise ratio (CNR) estimate after the phase value update is not less than the CNR estimate before the phase value update, the counter value is reset to zero, and the phase value of the phase shifter continues to be updated in the current increment or decrement direction (increase or decrease). If the CNR estimate after the phase value update is less than the CNR estimate before the phase value update, the counter value is incremented by 1.

[0120] If the counter value is equal to the threshold, change the direction of the phase value of the phase shifter. That is, if the phase value of the phase shifter was originally updated according to formula (2), then change it to update the phase value according to formula (3). If the phase value of the phase shifter was originally updated according to formula (3), then change it to update the phase value according to formula (2). And clear the counter value.

[0121] If the phase-locked loop is in an unlocked state during the phase value update process, then return to process A2.

[0122] It should be noted that the execution principles of A1 to A3 can be found in the above embodiments of the present invention. Figure 2 The details of each step are not elaborated here.

[0123] The above embodiments are descriptions of this solution. This solution uses a single-aperture dual-polarized antenna to simultaneously receive the RHCR and LHCR signal components in electromagnetic waves, and through a corresponding feedback control method, adaptively achieves the reverse cancellation of the RHCR and LHCR signal components, thereby suppressing electromagnetic interference.

[0124] In practical applications, this solution can be implemented using three parts: a GNSS single-aperture dual-polarized antenna, a GNSS receiving unit, and a phase iteration update and control unit; for example... Figure 3 The implementation principle architecture diagram of the interference suppression method based on a single-aperture dual-polarized antenna shown is as follows: Figure 3 It comprises three parts: a single-aperture dual-polarized antenna 301, a GNSS receiving unit 302, and a phase iteration update and control unit 303.

[0125] The single-aperture dual-polarized antenna 301 converts received electromagnetic waves into RHCR and LHCR signal components. After phase shifting the RHCR signal component, it combines it with the LHCR signal component for output. Specifically, a metal patch, dielectric, and a 90-degree coupler are used to convert the received electromagnetic waves into RHCR and LHCR signal components; a programmable phase shifter is used to shift the RHCR signal component; and a power combiner performs the combining (combining the LHCR signal component and the phase-shifted RHCR signal component).

[0126] The GNSS receiver unit 302 receives the output signal of the single-aperture dual-polarized antenna 301 and performs acquisition, tracking and carrier-to-noise ratio estimation processing on the GNSS signal based on the output signal.

[0127] The phase iteration update and control unit 303 updates the phase value of the programmable phase shifter based on the carrier-to-noise ratio estimation result and phase-locked loop state output by the GNSS receiving unit 302. Specifically, it can be implemented using digital logic devices with digital signal processing and storage functions, such as programmable logic controllers, digital signal processors, and application-specific integrated circuits.

[0128] More specifically, the phase iteration update and control unit 303 includes: a carrier-to-noise ratio (CNR) and lock-in state statistics module, a counter control module, a phase value calculation and update module, and a phase shifter phase control module. The CNR and lock-in state statistics module receives the CNR estimation result and phase-locked loop (PLL) state output by the GNSS receiver unit 302, and calculates and stores the CNR difference before and after the phase update. The counter control module controls the incrementing, decrementing, and resetting of the counter based on the CNR difference. The phase value calculation and update module calculates and updates the phase value based on the lock-in state and the counter result. The phase shifter phase control module controls the phase value of the programmable phase shifter. All of the aforementioned modules can be implemented using digital logic devices with digital signal processing and storage functions, such as programmable logic controllers, digital signal processors, and application-specific integrated circuits (ASICs).

[0129] Corresponding to the interference suppression method based on a single-aperture dual-polarized antenna provided in the above embodiments of the present invention, see also... Figure 4 The present invention also provides a structural block diagram of an interference suppression device based on a single-aperture dual-polarized antenna. The interference suppression device is applied to a drone and includes: a receiving unit 401, a determining unit 402, a processing unit 403, and an updating unit 404.

[0130] The receiving unit 401 is used to receive the RHCR signal component and LHCR signal component in the electromagnetic wave through a single-aperture dual-polarized antenna.

[0131] The determining unit 402 is used to determine the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component and the phase value of the phase shifter.

[0132] In a specific implementation, the determining unit 402 is specifically used to: use the phase value of the phase shifter to shift the RHCR signal component; combine the LHCR signal component and the phase-shifted RHCR signal component to obtain the output signal of the single-aperture dual-polarized antenna.

[0133] The processing unit 403 is used to capture and track the GNSS signal according to the output signal to obtain the phase-locked loop state, and to determine the carrier-to-noise ratio estimation result according to the output signal.

[0134] The update unit 404 is used to update the phase value of the phase shifter based on the phase-locked loop state and the carrier-to-noise ratio estimation result, and to execute the determination unit 402.

[0135] In this embodiment of the invention, a small single-array antenna with a single aperture dual polarization antenna is used to suppress GNSS interference. Without increasing the size, power consumption and weight of the GNSS receiver, the ability to suppress GNSS interference, especially broadband interference, can be improved.

[0136] Preferred, combined Figure 4 The update unit 404, as shown, includes: an increment module, a first acquisition module, a first processing module, a decrement module, a second acquisition module, and a second processing module; the execution principle of each module is as follows:

[0137] The increment module is used to increase the phase value of the phase shifter according to a preset increment formula when the phase-locked loop is in a locked state, and executes the determination unit 402.

[0138] The first acquisition module is used to acquire the carrier-to-noise ratio (CNR) estimation results before the phase value is increased and the CNR estimation results after the phase value is increased.

[0139] The first processing module increments the counter by 1 when the carrier-to-noise ratio (CNR) estimation result after the phase value increases is less than the CNR estimation result before the phase value increases; if the counter value is less than the threshold, the increment module is executed; if the counter value is equal to the threshold, the counter value is cleared to zero and the decrement module is executed.

[0140] The decrementing module is used to reduce the phase value of the phase shifter according to a preset decrementing formula, and executes the determination unit 402.

[0141] The second acquisition module is used to acquire the carrier-to-noise ratio (CNR) estimation results before the phase value decreases and the CNR estimation results after the phase value decreases.

[0142] The second processing module increments the counter by 1 when the estimated carrier-to-noise ratio after the phase value decreases is less than the estimated carrier-to-noise ratio before the phase value decreases; if the counter value is less than the threshold, the decrement module is executed; if the counter value is equal to the threshold, the counter value is cleared to zero and the increment module is executed.

[0143] In some embodiments, the update unit 404 further includes:

[0144] The third processing module is used to clear the counter value and execute the increment module when the carrier-to-noise ratio estimation result after the phase value increases is not less than the carrier-to-noise ratio estimation result before the phase value increases.

[0145] The fourth processing module is used to clear the counter value and execute the decrementing module when the carrier-to-noise ratio estimation result after the phase value decreases is not less than the carrier-to-noise ratio estimation result before the phase value decreases.

[0146] In some embodiments, the update unit 404 further includes:

[0147] The update module is used to increase the phase value of the phase shifter according to the increment formula when the phase-locked loop is in an unlocked state, and execute the determination unit 201 until the phase-locked loop state changes to a locked state.

[0148] In summary, the embodiments of the present invention provide an interference suppression method and apparatus based on a single-aperture dual-polarized antenna. By using a small single-array antenna, a single-aperture dual-polarized antenna, to suppress GNSS interference, the method can improve the suppression capability of GNSS interference, especially broadband interference, without increasing the size, power consumption, and weight of the GNSS receiver.

[0149] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0150] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0151] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An interference suppression method based on a single-aperture dual-polarized antenna, characterized in that, The method is applied to a drone, and the method includes: The right-hand circularly polarized (RHCR) signal component and the left-hand circularly polarized (LHCR) signal component in electromagnetic waves are received by a single-aperture dual-polarized antenna. The output signal of the single-aperture dual-polarized antenna is determined based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter. The phase-locked loop state is obtained by capturing and tracking GNSS signals of the Global Navigation Satellite System based on the output signal, and the carrier-to-noise ratio estimation result is determined based on the output signal. Based on the phase-locked loop (PLL) state and the carrier-to-noise ratio (CNR) estimation result, the phase value of the phase shifter is updated, and the step of determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter is executed. This includes: when the PLL state is locked, increasing the phase value of the phase shifter according to a preset increment formula, and determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter; obtaining the CNR estimation result before the phase value increase and the CNR estimation result after the phase value increase; when the CNR estimation result after the phase value increase is less than the CNR estimation result before the phase value increase, the counter value is incremented by 1; if the counter value is less than a threshold, when the PLL state is locked, the value of the phase shifter is increased according to the increment formula. The process involves the following steps: First, determining the phase value of the phase shifter; second, if the counter value equals the threshold, resetting the counter value to zero and decreasing the phase value of the phase shifter according to a preset decreasing formula; third, determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter; fourth, obtaining the carrier-to-noise ratio (CNR) estimation result before and after the phase value decreases; fifth, incrementing the counter value by 1 when the CNR estimation result after the phase value decreases is less than the CNR estimation result before the phase value decreases; sixth, decreasing the phase value of the phase shifter according to a preset decreasing formula if the counter value equals the threshold; seventh, resetting the counter value to zero and increasing the phase value of the phase shifter according to a preset increasing formula when the phase-locked loop (PLL) is in a locked state.

2. The method according to claim 1, characterized in that, Based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter, the output signal of the single-aperture dual-polarized antenna is determined, including: The RHCR signal component is phase-shifted using the phase value of a phase shifter; The LHCR signal component and the phase-shifted RHCR signal component are combined to obtain the output signal of the single-aperture dual-polarized antenna.

3. The method according to claim 1, characterized in that, The method further includes: When the estimated carrier-to-noise ratio after the phase value increases is not less than the estimated carrier-to-noise ratio before the phase value increases, the value of the counter is cleared to zero, and the step of increasing the phase value of the phase shifter according to the increment formula is executed when the phase-locked loop is in a locked state. If the estimated carrier-to-noise ratio after the phase value decreases is not less than the estimated carrier-to-noise ratio before the phase value decreases, the value of the counter is cleared to zero, and the step of decreasing the phase value of the phase shifter according to the preset decreasing formula is executed.

4. The method according to claim 1 or 3, characterized in that, The method further includes: When the phase-locked loop is in an unlocked state, the phase value of the phase shifter is increased according to the increment formula, and the step of determining the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component and the phase value of the phase shifter is performed until the phase-locked loop changes to a locked state.

5. An interference suppression device based on a single-aperture dual-polarized antenna, characterized in that, The device is used in a drone, and the device includes: The receiving unit is used to receive the right-hand circularly polarized (RHCR) signal component and the left-hand circularly polarized (LHCR) signal component in electromagnetic waves through a single-aperture dual-polarized antenna. The determining unit is used to determine the output signal of the single-aperture dual-polarized antenna based on the RHCR signal component, the LHCR signal component, and the phase value of the phase shifter; The processing unit is used to acquire and track the GNSS signal of the Global Navigation Satellite System according to the output signal to obtain the phase-locked loop state, and to determine the carrier-to-noise ratio estimation result according to the output signal; The update unit is used to update the phase value of the phase shifter based on the phase-locked loop state and the carrier-to-noise ratio estimation result, and to execute the determination unit; The update unit includes: An increment module is used to increase the phase value of the phase shifter according to a preset increment formula when the phase-locked loop is in a locked state, and to execute the determination unit. The first acquisition module is used to acquire the carrier-to-noise ratio estimation result before the phase value is increased and the carrier-to-noise ratio estimation result after the phase value is increased; The first processing module is configured to increment a counter by 1 when the estimated carrier-to-noise ratio after the phase value increases is less than the estimated carrier-to-noise ratio before the phase value increases; execute the increment module if the value of the counter is less than a threshold; and clear the value of the counter to zero and execute the decrement module if the value of the counter is equal to the threshold. The decreasing module is used to decrease the phase value of the phase shifter according to a preset decreasing formula and execute the determining unit; The second acquisition module is used to acquire the carrier-to-noise ratio estimation result before the phase value decreases and the carrier-to-noise ratio estimation result after the phase value decreases; The second processing module is used to increment the value of the counter by 1 when the estimated carrier-to-noise ratio after the phase value decreases is less than the estimated carrier-to-noise ratio before the phase value decreases; if the value of the counter is less than the threshold, execute the decrement module; if the value of the counter is equal to the threshold, clear the value of the counter to zero and execute the increment module.

6. The apparatus according to claim 5, characterized in that, The determining unit is specifically used to: shift the phase of the RHCR signal component using the phase value of the phase shifter; and combine the LHCR signal component and the phase-shifted RHCR signal component to obtain the output signal of the single-aperture dual-polarized antenna.

7. The apparatus according to claim 5, characterized in that, The update unit further includes: The third processing module is used to clear the value of the counter and execute the increment module when the carrier-to-noise ratio estimation result after the phase value increases is not less than the carrier-to-noise ratio estimation result before the phase value increases. The fourth processing module is used to clear the value of the counter and execute the decrementing module when the estimated carrier-to-noise ratio after the phase value decreases is not less than the estimated carrier-to-noise ratio before the phase value decreases.

8. The apparatus according to claim 5 or 7, characterized in that, The update unit further includes: The update module is used to increase the phase value of the phase shifter according to the increment formula when the phase-locked loop is in an unlocked state, and execute the determination unit until the phase-locked loop changes to a locked state.

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