GNSS (Global Navigation Satellite System) receiver performance evaluation method and device based on power sensitive characteristic index

Abstract

The invention discloses a GNSS receiver performance evaluation method and device based on a power sensitive characteristic index, and the method comprises the following steps: S1, giving a to-be-tested interference signal type set, a frequency set and a power value set, generating a to-be-tested interference signal, and when an interference generator is turned off and transmits the to-be-tested interference signal, carrying out the evaluation of the to-be-tested interference signal; signal receiving and frequency spectrum measurement are carried out through a GNSS receiver, and a reference frequency spectrum and a measurement frequency spectrum are obtained; s2, performing normalization processing on the interference spectrum and the measurement spectrum, and calculating a single-frequency cosine similarity between the measurement spectrum and the interference-free reference spectrum based on a normalization processing result; s3, introducing a weighted similarity concept, and fusing multi-frequency point information to obtain a power sensitive feature index; and S4, based on the power sensitive feature index, constructing a continuous index model to evaluate the performance of the GNSS receiver. According to the method, the quantitative description of the correlation between the spectrum characteristics and the interference parameters is realized, so that an accurate performance evaluation basis can be obtained.

Description

Technical Field

[0001] This invention relates to the field of GNSS signal reception, and in particular to a method and apparatus for evaluating the performance of GNSS receivers based on the power sensitivity index. Background Technology

[0002] Global Navigation Satellite Systems (GNSS), represented by the Global Positioning System (GPS), have become a core component of modern infrastructure, playing an irreplaceable role in critical areas such as aerospace navigation, autonomous driving, precision agriculture, and emergency response. However, the sensitivity of satellite navigation receivers to electromagnetic interference (EMI) poses a significant challenge to their performance. In particular, with the proliferation of wireless devices and increasing human-caused interference, GPS L1 band signals are threatened by various types of interference, including continuous wave (CW), pulse modulation, and BPSK modulation. These interferences can significantly affect receiver performance; therefore, evaluating the performance of GNSS receivers is crucial.

[0003] However, there are still some key issues with the response mechanism of the receiver's RF front end in complex electromagnetic environments. First, the traditional signal-to-interference-plus-noise ratio (SINR) evaluation framework is difficult to quantify the dynamic characteristics of the intermediate frequency output related to navigation faults. The spectrum threshold distribution patterns of different modulation types lack a universal theoretical framework, which limits the general design of anti-interference receivers. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a GNSS receiver performance evaluation method and device based on power-sensitive feature index. By constructing a "feature index-power" model and integrating multi-frequency information through weighted similarity, a quantitative description of the correlation between spectral features and interference parameters is achieved, thereby obtaining accurate performance evaluation basis.

[0005] The objective of this invention is achieved through the following technical solution: a GNSS receiver performance evaluation method based on the power-sensitive characteristic index, comprising the following steps:

[0006] Step S1. Given the set of interference signal types, frequency sets, and power value sets to be tested, generate the interference signal to be tested. When the interference generator is turned off and the interference signal to be tested is transmitted, the signal is received and the spectrum is measured by the GNSS receiver to obtain the reference spectrum and the measured spectrum.

[0007] Step S2. Normalize the interference spectrum and the measurement spectrum, and calculate the single-frequency cosine similarity between the measurement spectrum and the interference-free reference spectrum based on the normalization result;

[0008] Step S3. Introduce the concept of weighted similarity, fuse multi-frequency information, and obtain the power-sensitive feature index;

[0009] Step S4. Based on the power-sensitive feature index, construct a continuous exponential model to evaluate the performance of the GNSS receiver.

[0010] A GNSS receiver performance evaluation device based on the power-sensitive characteristic index includes:

[0011] The spectrum measurement module is used to generate the interference signal to be tested given a set of interference signal types, a set of frequencies, and a set of power values. When the interference generator is turned off and the interference signal to be tested is transmitted, the GNSS receiver receives the signal and performs spectrum measurement to obtain the reference spectrum and the measured spectrum.

[0012] The single-frequency cosine similarity calculation module normalizes the interference spectrum and the measurement spectrum, and calculates the single-frequency cosine similarity between the measurement spectrum and the interference-free reference spectrum based on the normalization result.

[0013] The weighted fusion module introduces the concept of weighted similarity and fuses information from multiple frequency points to obtain a power-sensitive feature index.

[0014] The performance evaluation module uses a continuous exponential model based on power-sensitive feature indexing to evaluate the performance of GNSS receivers.

[0015] The beneficial effects of the present invention are: (1) The present invention uses the L2 norm to normalize the spectrum vector, eliminating the influence of amplitude difference on subsequent calculations; (2) In order to reflect the device's sensitivity to power, the present invention first introduces an exponential penalty term in the single-frequency cosine similarity to obtain the single-frequency weighted similarity. Then, in order to reduce the influence of frequency fluctuations, the average value of the single-frequency weighted similarity is calculated to obtain the final weighted similarity of the method power level. By weighting the frequency used, multi-frequency information is integrated to finally obtain the power sensitive feature index. Then, a "feature index-power" model is constructed, and after fitting, it can complete the performance evaluation of GNSS receivers with arbitrary measured power. Attached Figure Description

[0016] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0018] like Figure 1 As shown, the GNSS receiver performance evaluation method based on the power-sensitive characteristic index includes the following steps:

[0019] Step S1. Given the set of interference signal types, frequency sets, and power value sets to be tested, generate the interference signal to be tested. When the interference generator is turned off and the interference signal to be tested is transmitted, the signal is received and the spectrum is measured by the GNSS receiver to obtain the reference spectrum and the measured spectrum.

[0020] Step S1 includes:

[0021] S101. Given the set of interference signal types to be tested as M= The frequency set is: The power value set is ;

[0022] Where, N m N f N P These represent the total number of types, frequencies, and power values ​​of the interference signals to be tested, respectively.

[0023] S102. Given the interference signal type m∈M, interference signal power p∈P, and interference signal frequency f∈F, generate the interference signal to be tested, transmit it through the interference generator, and have the GNSS receiver receive the GNSS signal under the interference signal and perform spectrum measurement to obtain the measured spectrum. ;

[0024] S103. When the interference generator is off, the GNSS receiver receives signals at multiple consecutive time points and performs spectrum measurements to obtain the spectrum vector under the "interference-free baseline," which is denoted as the reference spectrum. .

[0025] Step S2. Normalize the interference spectrum and the measurement spectrum, and calculate the single-frequency cosine similarity between the measurement spectrum and the interference-free reference spectrum based on the normalization result;

[0026] S201. Measuring the spectrum using L2 norm pairs Reference spectrum After normalization, we get:

[0027] ;

[0028] in, Indicates the measurement spectrum The result obtained after normalization Indicates the reference spectrum The result obtained after normalization; Represents the L2 norm;

[0029] S202. Calculate the single-frequency cosine similarity between the measured spectrum and the interference-free reference spectrum based on the normalization processing results. :

[0030] ;

[0031] in, The expression represents the inner product. At frequency f, the single-frequency cosine similarity between the normalized measured spectrum and the reference spectrum is equivalent to their inner product.

[0032] Step S3. Introduce the concept of weighted similarity, fuse multi-frequency information, and obtain the power-sensitive feature index;

[0033] Step S3 includes:

[0034] S301. To reflect the device's sensitivity to power, an exponential penalty term is first introduced into the single-frequency cosine similarity to obtain the single-frequency weighted similarity. :

[0035] ;

[0036] make Represents the power penalty term, where The attenuation factor represents the factor that controls the attenuation rate.

[0037] When the power approaches the reference power p0, the penalty term approaches 1, and the weighted similarity approaches the single-frequency cosine similarity. As the power increases, the penalty term grows exponentially, and the weighted similarity decays exponentially. This indicates that for electromagnetically sensitive devices, once the power exceeds the threshold, the performance will drop sharply.

[0038] S302. Use frequency-weighted integration of multi-frequency information to obtain the power-sensitive feature index. :

[0039] ;

[0040] in, These are weighting coefficients, with values ​​ranging from [0,1], representing frequency weights. = , To determine the Euclidean distance difference between the measured spectrum and the reference spectrum under conditions of interference signal type m, interference power p, and interference frequency f, the calculation formula is as follows:

[0041] .

[0042] Step S4. Based on the power-sensitive feature index, construct a continuous exponential model to evaluate the performance of the GNSS receiver.

[0043] Step S4 includes:

[0044] S401. First, when traversing the power set P for power p, repeat steps S1~S3 to obtain the corresponding values ​​for multiple power values. ;

[0045] S402. Constructing a continuous exponential model By utilizing different powers p and corresponding Scaling factor fitted by least squares method and attenuation coefficient ;

[0046] S403. For the measured interference signal power p, input it into the fitted continuous exponential model to obtain... Then it is compared with the interference sensitivity threshold. If it exceeds the threshold, the receiver is sensitive.

[0047] A GNSS receiver performance evaluation device based on the power-sensitive characteristic index includes:

[0048] The spectrum measurement module is used to generate the interference signal to be tested given a set of interference signal types, a set of frequencies, and a set of power values. When the interference generator is turned off and the interference signal to be tested is transmitted, the GNSS receiver receives the signal and performs spectrum measurement to obtain the reference spectrum and the measured spectrum.

[0049] The single-frequency cosine similarity calculation module normalizes the interference spectrum and the measurement spectrum, and calculates the single-frequency cosine similarity between the measurement spectrum and the interference-free reference spectrum based on the normalization result.

[0050] The weighted fusion module introduces the concept of weighted similarity and fuses information from multiple frequency points to obtain a power-sensitive feature index.

[0051] The performance evaluation module uses a continuous exponential model based on power-sensitive feature indexing to evaluate the performance of GNSS receivers.

[0052] The foregoing description illustrates and describes a preferred embodiment of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A GNSS receiver performance evaluation method based on the power sensitivity index, characterized in that: Includes the following steps: Step S1. Given the set of interference signal types, frequency sets, and power value sets to be tested, generate the interference signal to be tested. When the interference generator is turned off and the interference signal to be tested is transmitted, the signal is received and the spectrum is measured by the GNSS receiver to obtain the reference spectrum and the measured spectrum. Step S2. Normalize the interference spectrum and the measurement spectrum, and calculate the single-frequency cosine similarity between the measurement spectrum and the interference-free reference spectrum based on the normalization result; Step S3. Introduce the concept of weighted similarity, fuse multi-frequency information, and obtain the power-sensitive feature index; Step S4. Based on the power-sensitive feature index, construct a continuous exponential model to evaluate the performance of the GNSS receiver.

2. The GNSS receiver performance evaluation method based on the power sensitivity index according to claim 1, characterized in that: Step S1 includes: S101. Given the set of interference signal types to be tested as M= The frequency set is: The power value set is In the set of frequency values, each frequency increases sequentially from front to back with the same frequency increment; in the set of power values, each power increases sequentially from front to back with the same power increment. Where, N m N f N P These represent the total number of types, frequencies, and power values ​​of the interference signals to be tested, respectively. S102. Given the interference signal type m∈M, interference signal power p∈P, and interference signal frequency f∈F, generate the interference signal to be tested, transmit it through the interference generator, and have the GNSS receiver receive the GNSS signal under the interference signal and perform spectrum measurement to obtain the measured spectrum. ; S103. When the interference generator is off, the GNSS receiver receives signals at multiple consecutive time points and performs spectrum measurements to obtain the spectrum vector under the "interference-free baseline," which is denoted as the reference spectrum. .

3. The GNSS receiver performance evaluation method based on the power sensitivity index according to claim 2, characterized in that: Step S2 includes: S201. Measuring the spectrum using L2 norm pairs Reference spectrum After normalization, we get: ； in, Indicates the measurement spectrum The result obtained after normalization Indicates the reference spectrum The result obtained after normalization; Represents the L2 norm; S202. Calculate the single-frequency cosine similarity between the measured spectrum and the interference-free reference spectrum based on the normalization processing results. : ； in, The expression represents the inner product. At frequency f, the single-frequency cosine similarity between the normalized measured spectrum and the reference spectrum is equivalent to their inner product.

4. The GNSS receiver performance evaluation method based on the power sensitivity index according to claim 3, characterized in that: Step S3 includes: S301. To reflect the device's sensitivity to power, an exponential penalty term is first introduced into the single-frequency cosine similarity to obtain the single-frequency weighted similarity. : ； make Represents the power penalty term, where The attenuation factor represents the factor that controls the attenuation rate. When the power approaches the reference power p0, the penalty term approaches 1, and the weighted similarity approaches the single-frequency cosine similarity. As the power increases, the penalty term grows exponentially, and the weighted similarity decays exponentially. This indicates that for electromagnetically sensitive devices, once the power exceeds the threshold, the performance will drop sharply. S302. Use frequency-weighted integration of multi-frequency information to obtain the power-sensitive feature index. : ； in, These are weighting coefficients, with values ​​ranging from [0,1], representing frequency weights. = , To determine the Euclidean distance difference between the measured spectrum and the reference spectrum under conditions of interference signal type m, interference power p, and interference frequency f, the calculation formula is as follows: 。 5. The GNSS receiver performance evaluation method based on the power sensitivity index according to claim 1, characterized in that: Step S4 includes: S401. First, when traversing the power set P for power p, repeat steps S1~S3 to obtain the corresponding values ​​for multiple power values. ; S402. Constructing a continuous exponential model By utilizing different powers p and corresponding Scaling factor fitted by least squares method and attenuation coefficient ; S403. For the measured interference signal power p, input it into the fitted continuous exponential model to obtain... Then it is compared with the interference sensitivity threshold. If it exceeds the threshold, the receiver is sensitive.

6. A GNSS receiver performance evaluation device based on the power sensitivity index, comprising the method described in any one of claims 1 to 5, characterized in that: include: The spectrum measurement module is used to generate the interference signal to be tested given a set of interference signal types, a set of frequencies, and a set of power values. When the interference generator is turned off and the interference signal to be tested is transmitted, the GNSS receiver receives the signal and performs spectrum measurement to obtain the reference spectrum and the measured spectrum. The single-frequency cosine similarity calculation module normalizes the interference spectrum and the measurement spectrum, and calculates the single-frequency cosine similarity between the measurement spectrum and the interference-free reference spectrum based on the normalization result. The weighted fusion module introduces the concept of weighted similarity and fuses information from multiple frequency points to obtain a power-sensitive feature index. The performance evaluation module uses a continuous exponential model based on power-sensitive feature indexing to evaluate the performance of GNSS receivers.

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