A method for estimating the carrier-to-noise ratio of a satellite navigation array anti-jamming receiver in a given scenario.
By calculating the power of the third-order intermodulation component and the signal-to-noise ratio loss of the anti-jamming receiver of the satellite navigation array, and combining the correlation matrix and anti-jamming weights, the carrier-to-noise ratio is estimated by model deduction. This solves the problems of large engineering workload and high cost of the actual measurement method, and realizes efficient carrier-to-noise ratio evaluation and design guidance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-24
- Publication Date
- 2026-03-10
AI Technical Summary
Existing technologies for evaluating the carrier-to-noise ratio (CNR) of satellite navigation array anti-jamming receivers involve large engineering workloads and high costs, making it difficult to cover the CNR at every moment throughout the entire mission cycle.
By calculating the third-order intermodulation component power, signal-to-noise ratio loss, correlation matrix, and anti-interference weights of the receiver, the carrier-to-noise ratio is estimated using model deduction, simplifying the evaluation process.
It greatly simplifies the carrier-to-noise ratio (CNR) evaluation process, reduces evaluation costs, and enables the acquisition of the CNR of the satellite navigation array anti-jamming receiver at various times during the mission cycle, providing positioning and timing performance evaluation and design guidance.
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Figure CN117075154B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of satellite navigation, in particular to a carrier-to-noise ratio estimation method of a satellite navigation array anti-jamming receiver under a given scenario. BACKGROUND
[0002] A satellite navigation system can provide users with all-weather, all-day, high-precision positioning and timing services, and has been widely used in the fields of aviation, power, finance, transportation, communication, etc. With the development of technology towards unmanned and intelligent, it is foreseeable that the role of satellite navigation will be further highlighted. Electromagnetic interference is one of the main threats faced by satellite navigation. When a satellite navigation receiver is subjected to electromagnetic interference, the carrier-to-noise ratio of the satellite signal received by the satellite navigation receiver will decrease, resulting in deterioration of positioning accuracy. When the carrier-to-noise ratio decreases below the signal tracking threshold, the satellite navigation receiver will lose tracking of the satellite signal, resulting in failure to position. Studies have shown that a 1-watt electromagnetic interference can cause satellite navigation receivers within a range of several kilometers to fail to work normally. In order to cope with the threat of electromagnetic interference, the academic and industrial sectors have proposed a variety of satellite navigation anti-jamming methods. Among them, the adaptive nulling technology based on array antenna is proved to be the most effective, and has become the mainstream scheme adopted in high-value platforms. Satellite navigation receivers using this anti-jamming technology are also called satellite navigation array anti-jamming receivers. The carrier-to-noise ratio is an important indicator for evaluating the positioning and timing performance of a satellite navigation receiver, which directly determines whether the satellite navigation receiver can work normally and how high the positioning accuracy is. The carrier-to-noise ratio of a satellite navigation array anti-jamming receiver is closely related to the specific use scenario. The number, power and incident direction of satellite signals and interference, etc. Scene parameters will all affect its carrier-to-noise ratio. Even if the scene parameters are given, the carrier-to-noise ratio of the satellite navigation array anti-jamming receiver also depends on the nonlinearity of the hardware and the anti-jamming criterion adopted, and the mapping relationship is relatively complex. There is currently no publicly available model.
[0003] In order to obtain the carrier-to-noise ratio of a satellite navigation array anti-jamming receiver under a given scenario, the current main method is to rely on actual measurement. Usually, interference is applied in a dark room or an outdoor environment to simulate the real use scenario, and the output carrier-to-noise ratio is directly tested. The advantage of this method is that the evaluation result is accurate and consistent with the actual situation, but the disadvantage is also very obvious. First, the actual measurement has a large amount of engineering, strict requirements for the site and environment, and high implementation cost. Second, the actual measurement can only obtain the carrier-to-noise ratio of a few limited scenarios, and it is difficult to traverse the carrier-to-noise ratio of the satellite navigation array anti-jamming receiver at each time in a complete task cycle. SUMMARY
[0004] Therefore, it is necessary to provide a satellite navigation array anti-jamming receiver carrier-to-noise ratio estimation method in a given scenario, which can obtain the carrier-to-noise ratio of the satellite navigation array anti-jamming receiver at each time in a complete task cycle and reduce the implementation cost.
[0005] A satellite navigation array anti-jamming receiver carrier-to-noise ratio estimation method in a given scenario, the method comprises:
[0006] Obtaining the input power of the satellite navigation array anti-jamming receiver and the third-order intermodulation intercept point of the receiver itself;
[0007] According to the input power and the third-order intermodulation intercept point of the receiver itself, the power of the third-order intermodulation component of the receiver is calculated;
[0008] The third-order intermodulation component is equivalent to thermal noise, and the carrier-to-noise ratio loss caused by the third-order intermodulation is calculated according to the power of the third-order intermodulation component of the receiver;
[0009] According to the digital-to-analog converter effective bits of the satellite navigation array anti-jamming receiver, the signal-to-noise ratio of the sampled and quantized input of the digital-to-analog converter is calculated, and the carrier-to-noise ratio loss caused by the sampling and quantization of the receiver is calculated using the signal-to-noise ratio and the carrier-to-noise ratio loss caused by the third-order intermodulation;
[0010] According to the carrier-to-noise ratio loss caused by the third-order intermodulation and the carrier-to-noise ratio loss caused by the sampling and quantization of the receiver, the noise power after the third-order intermodulation loss and the sampling and quantization loss is calculated;
[0011] Using the noise power, the array signal received by the antenna array of the satellite navigation array anti-jamming receiver is calculated to obtain the correlation matrix of the array signal;
[0012] According to the correlation matrix, the anti-jamming weight is calculated, the array output signal-to-interference-and-noise ratio of the satellite navigation array anti-jamming receiver is estimated using the anti-jamming weight, and the carrier-to-noise ratio is calculated according to the array output signal-to-interference-and-noise ratio.
[0013] In one embodiment, according to the input power and the third-order intermodulation intercept point of the receiver itself, the power of the third-order intermodulation component of the receiver is calculated, comprising:
[0014] According to the input power and the third-order intermodulation intercept point of the receiver itself, the power of the third-order intermodulation component of the receiver is calculated, comprising:
[0015] P IM3 =OIP3-3·(IIP3-P in )
[0016]
[0017] Wherein, OIP3 is the output third-order intermodulation intercept point of the receiver, IIP3 is the input third-order intermodulation intercept point of the receiver, P IM3 is the power of the third-order intermodulation component of the receiver, P in is the input power, M is the number of interference, P jm is the power of the mth interference received by the receiver antenna port.
[0018] In one embodiment, the third-order intermodulation component is equivalent to thermal noise, and the loss calculation is performed according to the power of the third-order intermodulation component of the receiver, so as to obtain the carrier-to-noise ratio loss caused by the third-order intermodulation, including:
[0019] The third-order intermodulation component is equivalent to thermal noise, and the loss calculation is performed according to the power of the third-order intermodulation component of the receiver, so as to obtain the carrier-to-noise ratio loss caused by the third-order intermodulation
[0020]
[0021] N0=k·F·T
[0022] Wherein, R c is the code rate of the spread spectrum code in the signal, Q is the anti-interference quality factor, N0 is the noise spectral density of the receiver, k is the Boltzmann constant, T is the noise temperature, and F is the noise factor of the receiver.
[0023] In one embodiment, the signal-to-noise ratio of the sampled and quantized input of the digital-to-analog converter of the satellite navigation array anti-jamming receiver is calculated according to the effective bits of the digital-to-analog converter of the satellite navigation array anti-jamming receiver, including:
[0024] The signal-to-noise ratio of the sampled and quantized input of the digital-to-analog converter of the satellite navigation array anti-jamming receiver is calculated according to the effective bits of the digital-to-analog converter of the satellite navigation array anti-jamming receiver
[0025] SNR=6.02·b+1.76
[0026] Wherein, b is the effective bit of the digital-to-analog converter.
[0027] In one embodiment, the carrier-to-noise ratio loss caused by the sampling and quantization of the receiver is calculated by using the signal-to-noise ratio and the carrier-to-noise ratio loss caused by the third-order intermodulation, including:
[0028] The carrier-to-noise ratio loss caused by the sampling and quantization of the receiver is calculated by using the signal-to-noise ratio and the carrier-to-noise ratio loss caused by the third-order intermodulation
[0029]
[0030] Wherein, B is the front-end bandwidth of the receiver, N0 is the noise spectral density of the receiver, L1 is the carrier-to-noise ratio loss caused by the third-order intermodulation, P in is the input power.
[0031] In one embodiment, the correlation matrix of the array signal received by the antenna array of the satellite navigation array anti-jamming receiver is calculated using noise power, including:
[0032] The correlation matrix of the array signal is obtained by calculating the array signal received by the antenna array of the satellite navigation array anti-jamming receiver using noise power.
[0033]
[0034] σ 2 =L1·L2·N0·B
[0035] Where K is the number of satellite signals received by the receiver, and P sk Let a be the power of the k-th satellite signal received at the receiver antenna aperture. k Let b be the steering vector of the k-th satellite signal. m Let M be the steering vector of the m-th interference, and M be the number of interferences. H Indicates the conjugate transpose, σ 2 Let I be the noise power after third-order intermodulation loss and sampling quantization loss, and let P be the N-dimensional identity matrix. jm Let m be the power of the m-th interference received at the receiver antenna aperture.
[0036] In one embodiment, the anti-interference weights are calculated based on the correlation matrix, including:
[0037] The anti-interference weights are calculated based on the correlation matrix.
[0038]
[0039] Where c is the constraint vector, (·) H This indicates the conjugate transpose.
[0040] In one embodiment, estimating the array output signal-to-interference-plus-noise ratio (SIR) of a satellite navigation array anti-jamming receiver using anti-jamming weights includes:
[0041] The signal-to-interference-plus-noise ratio (SNR) of the array output of the satellite navigation array anti-jamming receiver is estimated using anti-jamming weights.
[0042]
[0043] Where w is the anti-interference weight, (·) H P represents the conjugate transpose. si a represents the power of the i-th satellite signal received at the receiver antenna aperture. i P represents the steering vector of the i-th satellite signal. skLet a be the power of the k-th satellite signal received at the receiver antenna aperture. k Let b be the steering vector of the k-th satellite signal. m Let M be the steering vector of the m-th interference, and M be the number of interferences. H Indicates the conjugate transpose, σ 2 To account for the noise power after considering third-order intermodulation loss and sampling quantization loss, let I be an N-dimensional identity matrix, and P... jm Let be the power of the m-th interference received at the receiver antenna aperture, and K be the number of satellite signals received by the receiver.
[0044] In one embodiment, the carrier-to-noise ratio is calculated based on the array output signal-to-interference-plus-noise ratio, including:
[0045] The carrier-to-noise ratio is calculated based on the array output signal-to-interference-plus-noise ratio.
[0046] CNR o =SINR+10lg(B)
[0047] Where B is the front-end bandwidth of the receiver.
[0048] The aforementioned carrier-to-noise ratio (CNR) estimation method for a satellite navigation array anti-jamming receiver in a given scenario first calculates the power of the receiver's third-order intermodulation (CNR) component based on the receiver's input power and its own third-order intermodulation intercept point. This third-order CNR component is then equated to thermal noise. Loss calculations are performed based on the power of the third-order CNR component to obtain the CNR loss caused by the third-order CNR. The signal-to-noise ratio (SNR) of the digital-to-analog converter (DAC) input after sampling and quantization is calculated based on the effective bits of the DAC. The CNR loss caused by sampling and quantization is then calculated using the SNR and the CNR loss caused by the third-order CNR. Finally, the noise power after the third-order CNR loss and sampling and quantization loss is calculated. The acoustic power is calculated based on the array signal received by the antenna array of the satellite navigation array anti-jamming receiver to obtain the correlation matrix of the array signal. Anti-jamming weights are then calculated based on the correlation matrix, and the array output signal-to-interference-plus-noise ratio (SIR / NDR) of the satellite navigation array anti-jamming receiver is estimated using these weights. The carrier-to-noise ratio (CNR) is then calculated based on the array output SIR / NDR. By extracting key parameters affecting the CNR of the satellite navigation array anti-jamming receiver and estimating the CNR of the receiver in a given scenario through model derivation, the evaluation process is greatly simplified, and evaluation efficiency is improved. This solves the problems of large workload and high cost associated with traditional measurement methods, and provides the possibility of traversing the anti-jamming performance of the receiver throughout the entire mission, enabling the acquisition of the CNR of the satellite navigation array anti-jamming receiver at various moments in a complete mission cycle. This invention provides a means and basis for evaluating the positioning and timing performance of satellite navigation receivers performing various tasks, and can also be used to guide the design of satellite navigation array anti-jamming receivers. Attached Figure Description
[0049] Figure 1 This is a flowchart illustrating a method for estimating the carrier-to-noise ratio of a satellite navigation array anti-jamming receiver in a given scenario, as described in one embodiment.
[0050] Figure 2 This is a diagram showing the carrier-to-noise ratio estimation result of a satellite navigation array anti-jamming receiver in a given scenario in one embodiment. Detailed Implementation
[0051] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0052] In one embodiment, such as Figure 1 As shown, a method for estimating the carrier-to-noise ratio of a satellite navigation array anti-jamming receiver in a given scenario is provided, including the following steps:
[0053] Step 102: Obtain the input power of the satellite navigation array anti-jamming receiver and the receiver's own third-order intermodulation intercept point; calculate the power of the receiver's third-order intermodulation component based on the input power and the receiver's own third-order intermodulation intercept point.
[0054] The receiver's own third-order intermodulation intercept point includes the receiver's output third-order intermodulation intercept point and the receiver's input third-order intermodulation intercept point. These two parameters are the key parameters extracted in this application and are used for subsequent calculations of the receiver's relevant power.
[0055] Step 104: The third-order intermodulation component is equivalent to thermal noise. The loss is calculated based on the power of the third-order intermodulation component of the receiver to obtain the carrier-to-noise ratio loss caused by the third-order intermodulation.
[0056] The third-order intermodulation component is equivalent to thermal noise, and the carrier-to-noise ratio loss is calculated using key parameters such as the spread spectrum code rate, anti-interference quality factor, Boltzmann constant, noise temperature, and receiver noise figure.
[0057] Step 106: Calculate the signal-to-noise ratio (SNR) of the digital-to-analog converter input after sampling and quantization based on the effective bits of the digital-to-analog converter of the satellite navigation array anti-interference receiver. Calculate the carrier-to-noise ratio loss caused by the receiver sampling and quantization using the SNR and the carrier-to-noise ratio loss caused by third-order intermodulation.
[0058] Sampling quantization is performed by the receiver's AD (analog-to-digital converter). First, the signal-to-noise ratio (SNR) of the AD input after sampling quantization is calculated based on the effective bits of the receiver's AD. Then, the carrier-to-noise ratio (CNR) loss caused by the receiver's sampling quantization is calculated using the SNR.
[0059] Step 108: Calculate the noise power after the third-order intermodulation loss and sampling quantization loss based on the carrier-to-noise ratio loss caused by the third-order intermodulation and the carrier-to-noise ratio loss caused by the receiver sampling quantization; use the noise power to calculate the array signal received by the antenna array of the satellite navigation array anti-interference receiver to obtain the correlation matrix of the array signal.
[0060] Step 110: Calculate the anti-interference weights based on the correlation matrix, estimate the array output signal-to-interference-plus-noise ratio (SIR) of the satellite navigation array anti-interference receiver using the anti-interference weights, and calculate the carrier-to-noise ratio (CNR) based on the array output SIR.
[0061] The correlation matrix of the array signal is calculated based on key parameters such as the number of array antenna elements and constraint vectors. Anti-interference weights are then calculated from the correlation matrix, and the array output signal-to-interference-plus-noise ratio (SIR) of the satellite navigation array anti-interference receiver is estimated using these weights. The carrier-to-noise ratio (CNR) is then calculated based on the array output SIR. By extracting key parameters affecting the CNR of the satellite navigation array anti-interference receiver and estimating the CNR of the receiver in a given scenario through model deduction, the evaluation process is greatly simplified, and evaluation efficiency is improved. This solves the problems of large workload and high cost associated with traditional measurement methods, and makes it possible to traverse the anti-interference performance of the receiver throughout the entire mission, enabling the acquisition of the CNR of the satellite navigation array anti-interference receiver at various moments throughout a complete mission cycle.
[0062] In the aforementioned method for estimating the carrier-to-noise ratio (CNR) of a satellite navigation array anti-jamming receiver in a given scenario, the power of the third-order intermodulation (CNR) component is first calculated based on the receiver's input power and its own third-order intermodulation intercept point. This power is then equated to thermal noise. Loss calculations are performed based on the power of the third-order CNR component to obtain the CNR loss caused by the third-order intermodulation. The signal-to-noise ratio (SNR) of the digital-to-analog converter (DAC) input after sampling and quantization is calculated based on the effective bits of the DAC. The CNR loss caused by sampling and quantization is then calculated using the SNR and the CNR loss caused by the third-order intermodulation. Finally, the noise power after the third-order intermodulation loss and sampling and quantization loss is calculated based on the CNR loss caused by the third-order intermodulation and the CNR loss caused by the sampling and quantization. The noise power is calculated based on the array signal received by the antenna array of the satellite navigation array anti-jamming receiver to obtain the correlation matrix of the array signal. Anti-jamming weights are then calculated based on the correlation matrix, and the array output signal-to-interference-plus-noise ratio (SIR / NDR) of the satellite navigation array anti-jamming receiver is estimated using these weights. The carrier-to-noise ratio (CNR) is then calculated based on the array output SIR / NDR. By extracting key parameters affecting the CNR of the satellite navigation array anti-jamming receiver and estimating the CNR of the receiver in a given scenario through model deduction, the evaluation process is greatly simplified, and evaluation efficiency is improved. This solves the problems of large workload and high cost associated with traditional measurement methods, and provides the possibility of traversing the anti-jamming performance of the receiver throughout the entire mission, enabling the acquisition of the CNR of the satellite navigation array anti-jamming receiver at various moments in a complete mission cycle. This invention provides a means and basis for evaluating the positioning and timing performance of satellite navigation receivers performing various tasks, and can also be used to guide the design of satellite navigation array anti-jamming receivers.
[0063] In one embodiment, the power of the receiver's third-order intermodulation component is calculated based on the input power and the receiver's own third-order intermodulation intercept point, including:
[0064] Based on the input power and the receiver's own third-order intermodulation intercept point, the power of the receiver's third-order intermodulation component is calculated as follows:
[0065] P IM3 =OIP3-3·(IIP3-P in )
[0066]
[0067] Where OIP3 is the receiver's output third-order intermodulation intercept point, IIP3 is the receiver's input third-order intermodulation intercept point, and P... IM3 P represents the power of the receiver's third-order intermodulation component. in Where P is the input power, M is the number of interferences, and P is the input power. jm Let m be the power of the m-th interference received at the receiver antenna aperture.
[0068] In one embodiment, the third-order intermodulation component is equivalent to thermal noise, and the power loss of the third-order intermodulation component of the receiver is calculated to obtain the carrier-to-noise ratio loss, including:
[0069] The third-order intermodulation component is treated as thermal noise. Loss is calculated based on the power of the third-order intermodulation component at the receiver, yielding the carrier-to-noise ratio loss caused by the third-order intermodulation.
[0070]
[0071] N0=k·F·T
[0072] Among them, R c Let be the code rate of the spreading code in the signal, Q be the anti-interference quality factor, N0 be the noise spectral density of the receiver, k be the Boltzmann constant, T be the noise temperature, and F be the noise figure of the receiver.
[0073] In one embodiment, the signal-to-noise ratio (SNR) of the digital-to-analog converter input after sampling and quantization is calculated based on the effective bits of the digital-to-analog converter (DAC) of the satellite navigation array anti-jamming receiver, including:
[0074] The signal-to-noise ratio (SNR) of the digital-to-analog converter (DAC) input after sampling and quantization is calculated based on the effective bits of the DAC in the satellite navigation array anti-jamming receiver.
[0075] SNR = 6.02·b + 1.76
[0076] Where b represents the valid bit of the digital-to-analog converter.
[0077] In one embodiment, the carrier-to-noise ratio loss caused by receiver sampling quantization is calculated using the signal-to-noise ratio and the carrier-to-noise ratio loss caused by third-order intermodulation, including:
[0078] The carrier-to-noise ratio loss caused by receiver sampling quantization is calculated using the signal-to-noise ratio and the carrier-to-noise ratio loss caused by third-order intermodulation.
[0079]
[0080] Where B is the receiver's front-end bandwidth, N0 is the receiver's noise spectral density, L1 is the carrier-to-noise ratio loss caused by third-order intermodulation, and P... in This refers to the input power.
[0081] In one embodiment, the correlation matrix of the array signal received by the antenna array of the satellite navigation array anti-jamming receiver is calculated using noise power, including:
[0082] The correlation matrix of the array signal is obtained by calculating the array signal received by the antenna array of the satellite navigation array anti-jamming receiver using noise power.
[0083]
[0084] σ 2 =L1·L2·N0·B
[0085] Where K is the number of satellite signals received by the receiver, and P sk Let a be the power of the k-th satellite signal received at the receiver antenna aperture. k Let b be the steering vector of the k-th satellite signal. m Let M be the steering vector of the m-th interference, and M be the number of interferences. H Indicates the conjugate transpose, σ 2 To account for the noise power after considering third-order intermodulation loss and sampling quantization loss, let I be an N-dimensional identity matrix, and P... jm Let m be the power of the m-th interference received at the receiver antenna aperture.
[0086] In a specific embodiment, the noise power after calculating the third-order intermodulation loss and sampling quantization loss is first obtained by using the carrier-to-noise ratio loss caused by the third-order intermodulation and the carrier-to-noise ratio loss caused by receiver sampling quantization.
[0087] σ 2 =L1·L2·N0·B;
[0088] Then, the noise power is used to calculate the array signal received by the antenna array of the satellite navigation array anti-jamming receiver.
[0089] When the usage scenario is given, the number, power, and elevation angle of satellite signals, the number, power, and elevation angle of interference, and the relative coordinates of the array antenna can all be obtained from the scenario parameters.
[0090] In one embodiment, the anti-interference weights are calculated based on the correlation matrix, including:
[0091] The anti-interference weights are calculated based on the correlation matrix.
[0092]
[0093] Where c is the constraint vector, (·) H This indicates the conjugate transpose.
[0094] In a specific embodiment, the anti-interference weight w is an N-dimensional column vector. The constraint vector c is also an N-dimensional column vector, determined by the array anti-interference criteria. For example, when using the adaptive zeroing criterion, the first element of the constraint vector is 1, and the remaining elements are 0. When using the beam pointing criterion, the constraint vector is equal to the steering vector of the satellite signal to which the beam is pointing. The receiver's anti-interference criteria are the key parameters extracted in this application.
[0095] In one embodiment, estimating the array output signal-to-interference-plus-noise ratio (SIR) of a satellite navigation array anti-jamming receiver using anti-jamming weights includes:
[0096] The signal-to-interference-plus-noise ratio (SNR) of the array output of the satellite navigation array anti-jamming receiver is estimated using anti-jamming weights.
[0097]
[0098] Where w is the anti-interference weight, (·) H P represents the conjugate transpose. si a represents the power of the i-th satellite signal received at the receiver antenna aperture. i P represents the steering vector of the i-th satellite signal. sk Let a be the power of the k-th satellite signal received at the receiver antenna aperture. k Let b be the steering vector of the k-th satellite signal. m Let M be the steering vector of the m-th interference, and M be the number of interferences. H Indicates the conjugate transpose, σ 2 To account for the noise power after considering third-order intermodulation loss and sampling quantization loss, let I be an N-dimensional identity matrix, and P... jm Let be the power of the m-th interference received at the receiver antenna aperture, and K be the number of satellite signals received by the receiver.
[0099] In one embodiment, the carrier-to-noise ratio is calculated based on the array output signal-to-interference-plus-noise ratio, including:
[0100] The carrier-to-noise ratio is calculated based on the array output signal-to-interference-plus-noise ratio.
[0101] CNR o =SINR+10lg(B)
[0102] Where B is the front-end bandwidth of the receiver.
[0103] In a specific embodiment, such as Figure 2 As shown, in this embodiment, the usage scenario is that the satellite navigation array anti-jamming receiver is placed flat on a turntable in a microwave anechoic chamber, and the turntable rotates uniformly at a speed of 1 degree per second for one revolution. The specific scenario parameters are as follows: the number of interference sources is 2, with a power of -40dBm reaching the receiver antenna aperture; the incident elevation angles are 6 degrees and 10 degrees, and the initial azimuth angles are 60 degrees and 120 degrees, respectively; the interference type is Gaussian broadband interference, and the anti-jamming quality factor is 2.22; the number of satellite signals is 1, the signal is a BeiDou B3 frequency BPSK signal, the code rate is 10.23Mcps, the power reaching the receiver antenna aperture is -130dBm, the incident elevation angle is 80 degrees, and the initial azimuth angle is 0 degrees. The array antenna is a central circular array with a radius equal to half the wavelength of the satellite signal. The key parameters extracted by the method of this invention are as follows: the output third-order intermodulation intercept point is 33dBm, the input third-order intermodulation intercept point is 18dBm, the receiver noise figure is 2dB, the effective AD bits are 14 bits, the number of array antenna elements is 7, and the array anti-interference criterion adopted is the adaptive nulling criterion. Figure 2 The horizontal axis represents the azimuth angle of the satellite signal during receiver rotation, and the vertical axis represents the carrier-to-noise ratio (CNR) of the receiver output. As can be seen from the figure, the results estimated by this method agree well with the measured results, with an error within 3 dB. This method is entirely based on model calculations, thus greatly simplifying the evaluation process and reducing evaluation costs compared to experimental methods.
[0104] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.
[0105] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0106] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A method for estimating the carrier-to-noise ratio of a satellite navigation array anti-jam receiver in a given scenario, characterized in that, The method comprises: Obtaining input power of a satellite navigation array anti-jamming receiver and third-order intermodulation intercept point of the receiver itself; Calculating the input power and the third-order intermodulation intercept point of the receiver itself to obtain power of a third-order intermodulation component of the receiver; Equivalent the third-order intermodulation component to thermal noise, and calculating the power of the third-order intermodulation component of the receiver to obtain carrier-to-noise ratio loss caused by the third-order intermodulation according to the carrier-to-noise ratio loss; Calculating the input signal-to-noise ratio of a digital-to-analog converter of the satellite navigation array anti-jamming receiver according to the effective bits of the digital-to-analog converter, and calculating the carrier-to-noise ratio loss caused by sampling and quantization of the receiver by using the input signal-to-noise ratio and the carrier-to-noise ratio loss caused by the third-order intermodulation; Calculating the noise power after third-order intermodulation loss and sampling and quantization loss according to the carrier-to-noise ratio loss caused by the third-order intermodulation and the carrier-to-noise ratio loss caused by sampling and quantization of the receiver; Calculating the array signal correlation matrix by using the noise power on the array signal received by the antenna array of the satellite navigation array anti-jamming receiver; Calculating the anti-jamming weight according to the array signal correlation matrix, and estimating the array output signal-to-interference-and-noise ratio of the satellite navigation array anti-jamming receiver by using the anti-jamming weight, and calculating the carrier-to-noise ratio according to the array output signal-to-interference-and-noise ratio.
2. The method of claim 1, wherein, The calculating the input power and the third-order intermodulation intercept point of the receiver itself to obtain power of a third-order intermodulation component of the receiver comprises: The calculating the input power and the third-order intermodulation intercept point of the receiver itself to obtain power of a third-order intermodulation component of the receiver is P IM3 = OIP3-3 · (IIP3-P in ) where OIP3 is the output third order intercept point of the receiver, IIP3 is the input third order intercept point of the receiver, P IM3 is the power of the third order intermodulation component of the receiver, P in is the input power, M is the number of interferers, P jm is the power of the mth interferer received at the antenna port of the receiver.
3. The method of claim 2, wherein, The equivalent the third-order intermodulation component to thermal noise, and calculating the power of the third-order intermodulation component of the receiver to obtain carrier-to-noise ratio loss caused by the third-order intermodulation according to the carrier-to-noise ratio loss comprises: The equivalent the third-order intermodulation component to thermal noise, and calculating the power of the third-order intermodulation component of the receiver to obtain carrier-to-noise ratio loss caused by the third-order intermodulation according to the carrier-to-noise ratio loss is N0=k·F·T Among them, R c Let be the code rate of the spreading code in the signal, Q be the anti-interference quality factor, N0 be the noise spectral density of the receiver, k be the Boltzmann constant, T be the noise temperature, and F be the noise figure of the receiver.
4. The method according to any one of claims 1 to 3, characterized in that, The calculating the input signal-to-noise ratio of a digital-to-analog converter of the satellite navigation array anti-jamming receiver according to the effective bits of the digital-to-analog converter comprises: The calculating the input signal-to-noise ratio of a digital-to-analog converter of the satellite navigation array anti-jamming receiver according to the effective bits of the digital-to-analog converter is SNR=6.02·b+1.76 Wherein, b is the effective bits of the digital-to-analog converter.
5. The method of claim 4, wherein, The calculating the carrier-to-noise ratio loss caused by sampling and quantization of the receiver by using the input signal-to-noise ratio and the carrier-to-noise ratio loss caused by the third-order intermodulation comprises: The calculating the carrier-to-noise ratio loss caused by sampling and quantization of the receiver by using the input signal-to-noise ratio and the carrier-to-noise ratio loss caused by the third-order intermodulation is where B is the receiver's front-end bandwidth, N0is the receiver's noise spectral density, L1is the carrier-to-noise ratio loss due to third-order intermodulation, P in is the input power.
6. The method of claim 5, wherein, The calculating the array signal correlation matrix by using the noise power on the array signal received by the antenna array of the satellite navigation array anti-jamming receiver comprises: The calculating the array signal correlation matrix by using the noise power on the array signal received by the antenna array of the satellite navigation array anti-jamming receiver is σ 2 = L1 L2 N0 B where K is the number of satellite signals received by the receiver, P sk P k is the power of the kth satellite signal received by the receiver antenna aperture, a k a k is the steering vector of the kth satellite signal, b m b m is the steering vector of the mth interferer, M is the number of interferers, (·) H denotes the conjugate transpose, σ 2 σ 2 is the noise power after third-order intermodulation loss and sampling quantization loss, I is the N-dimensional identity matrix, P jm P m is the power of the mth interferer received by the receiver antenna aperture.
7. The method of claim 6, wherein, The calculating the anti-jamming weight according to the array signal correlation matrix comprises: The calculating the anti-jamming weight according to the array signal correlation matrix is where c is a constraint vector, (·) H denotes the conjugate transpose.
8. The method of claim 1, wherein, The estimating the array output signal-to-interference-and-noise ratio of the satellite navigation array anti-jamming receiver by using the anti-jamming weight comprises: An array output signal-to-interference-plus-noise ratio of the satellite navigation array anti-jam receiver is estimated using the anti-jam weight where w is the anti-jamming weight, (·) H denotes the conjugate transpose, P si denotes the power of the i-th satellite signal received by the receiver antenna port, a i denotes the steering vector of the i-th satellite signal, P sk denotes the power of the k-th satellite signal received by the receiver antenna port, a k denotes the steering vector of the k-th satellite signal, b m denotes the steering vector of the m-th interference, M is the number of interferences, (·) H denotes the conjugate transpose, σ 2 denotes the noise power considering the third-order intermodulation loss and sampling quantization loss, I is an N-dimensional unit matrix, P jm denotes the power of the m-th interference received by the receiver antenna port, K is the number of satellite signals received by the receiver.
9. The method of claim 8, wherein, A carrier-to-noise ratio is calculated from the array output signal-to-interference-plus-noise ratio, including: A carrier-to-noise ratio is calculated from the array output signal-to-interference-plus-noise ratio CNR o = SINR + 10lg(B) Where B is a front-end bandwidth of the receiver.