A receiver interference state prediction method for homotype device adjacent frequency interference

Abstract

The application discloses a receiver disturbed state prediction method for homotype device adjacent frequency interference, and belongs to the technical field of electromagnetic compatibility, and comprises the following steps: based on an interference signal spectrum, signal average power of adjacent frequency interference signals with different frequency offsets coupled through a receiving channel is predicted; processing benefits of the adjacent frequency interference signals with different frequency offsets after passing through a receiver signal processing channel are predicted, and a relative relationship between the processing benefits and the frequency offsets is obtained; based on the signal average power and the relative relationship between the processing benefits and the frequency offsets, adjacent frequency interference signals are converted into response equivalent homochromatic interference signals through amplitude equivalence; and a disturbed state of the receiver is predicted based on a homochromatic interference signal sensitive threshold. Through the application, equivalent interference power of homochromatic signals response equivalent to the adjacent frequency interference signals can be calculated.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electromagnetic compatibility, and more particularly relates to a receiver interference state prediction method for homotype device adjacent frequency interference. BACKGROUND

[0002] For receiver interference state prediction, it is difficult to guarantee prediction accuracy through full-digital simulation method, and usually, receiver sensitivity thresholds under different interference signals are obtained in advance through installation test, and when prediction is performed, the interference signal power coupled through the receiving channel is compared with the sensitivity threshold, so that the receiver interference state prediction is realized. For adjacent frequency interference signals, due to the specificity of the sidebands of different signals, installation test cannot cover all cases. SUMMARY

[0003] In view of the above defects or improvement needs of the prior art, the application provides a receiver interference state prediction method for homotype device adjacent frequency interference, which can calculate the equivalent interference power of a homochromatic signal equivalent to the response of an adjacent frequency interference signal.

[0004] To achieve the above purpose, the application provides a receiver interference state prediction method for homotype device adjacent frequency interference, comprising:

[0005] Predicting the signal average power of the adjacent frequency interference signal of different frequency offset amounts coupled through the receiving channel;

[0006] Predicting the processing benefit of the adjacent frequency interference signal of different frequency offset amounts after passing through the signal processing channel of the receiver, to obtain the relative relationship between the processing benefit and the frequency offset amount;

[0007] Based on the signal average power and the relative relationship between the processing benefit and the frequency offset amount, the adjacent frequency interference signal is converted into a homochromatic interference signal equivalent in response through amplitude equivalence, and the interference state of the receiver is predicted based on the homochromatic interference signal sensitivity threshold.

[0008] In some optional embodiments, the signal average power of the adjacent frequency interference signal of different frequency offset amounts coupled through the receiving channel is predicted, wherein P The processing benefit of the adjacent frequency interference signal of different frequency offset amounts after passing through the signal processing channel of the receiver is predicted, to obtain the relative relationship between the processing benefit and the frequency offset amount. mean P (Δf) is the signal average power of the adjacent frequency interference signal with a frequency offset amount of Δf coupled into the receiver through the receiving channel, P (f) is the normalized baseband signal spectrum of the receiver interference signal, and B is the bandwidth of the receiver.

[0009] In some optional embodiments, the processing benefit of the adjacent frequency interference signal of different frequency offset amounts after passing through the signal processing channel of the receiver is predicted, to obtain the relative relationship between the processing benefit and the frequency offset amount, comprising:

[0010] For adjacent frequency interference signals, interference signals with different frequency offsets are filtered by a receiver receiving channel, affecting signal processing benefits brought by pulse compression, and the pulse compression signal processing benefits are predicted according to frequency segmentation, which is divided into a main frequency band and a sideband, and thus the pulse compression processing benefits of the sideband signal and the pulse compression processing benefits of the main frequency band are predicted based on signal spectrum.

[0011] In some optional embodiments, the G MF (Δf) = P re , |Δf| > B the pulse compression processing benefits of the sideband signal are predicted based on signal spectrum, wherein the G MF (Δf) is the pulse compression processing benefits, the P re is a sideband signal pulse compression processing benefits correction amount caused by randomness of the signal, and is equal to the average value of the difference between P(Δf) and P mean (Δf) except for -2B < Δf < 2B.

[0012] In some optional embodiments, the G -B < Δf < B the pulse compression processing benefits of the main frequency band are predicted based on theoretical calculation, wherein the G MFmax is the pulse compression processing benefits when the interference signal is completely matched with the matched filter.

[0013] In some optional embodiments, taking a linear frequency modulation signal as an example, the power benefits satisfy the signal time pulse width product: G MFmax = 10log 10 (B·τ), τ represents the time pulse width.

[0014] In some optional embodiments, the adjacent frequency interference signal is converted into a response equivalent same frequency interference signal through amplitude equivalence based on the relative relationship between the signal average power and the processing benefits and the frequency offset, comprising:

[0015] The G MF (Δf) + P mean (Δf) predicts the receiver response signal amplitude change relationship corresponding to the adjacent frequency interference signal with different frequency offsets based on the relative relationship between the signal average power and the processing benefits and the frequency offset;

[0016] For an adjacent frequency interference signal with a peak power P max and a frequency offset Δf, the adjacent frequency interference signal is equivalent to a same frequency interference signal with a peak power P eq (Δf), wherein the P eq (Δf) = P max -P G_norm (Δf), the P G_norm (Δf) is a normalized result of the G MF (Δf) + P mean (Δf).

[0017] In some optional embodiments, the step of predicting the disturbed state of the receiver based on the co-channel interference signal sensitivity threshold value comprises:

[0018] By comparing P eq (Δf) and the co-channel interference signal sensitivity threshold value P gate , the disturbed state of the receiver under the adjacent channel interference signal is predicted, wherein when P eq (Δf)≥P gate , the receiver is in the disturbed state; and when P eq (Δf)<P gate , the receiver is in the undisturbed state.

[0019] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects:

[0020] The present application provides a receiver disturbed state prediction method for adjacent channel interference signals, and proposes a receiver coupling power prediction method based on signal spectrum, a signal processing benefit prediction method, and a receiver disturbed state prediction method, thereby solving the problem of predicting the sensitive response and disturbed state of the receiver under different offset adjacent channel interference signals. The present application has simple and clear principles and strong engineering practicability. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a flowchart of a receiver disturbed state prediction method for adjacent channel interference signals provided by an embodiment of the present application;

[0022] Figure 2 is a schematic diagram of the baseband spectrum of a typical narrowband receiver interference signal and the average power prediction value of the signal coupled into the receiver through the receiver receiving channel;

[0023] Figure 3 is a schematic diagram of the pulse pressure processing benefit prediction value of a typical receiver interference signal;

[0024] Figure 4 is a schematic diagram of the comparison between the prediction result and the test result of a typical receiver interference signal. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0026] The purpose of the present application is to predict the sensitive response and disturbed state of the receiver under different offset adjacent channel interference signals. The adjacent channel interference signals are converted into response equivalent same frequency interference signals through amplitude equivalence by comprehensively considering the influence of the receiving channel coupling and signal processing, and the disturbed state of the receiver is predicted based on the sensitive threshold of the same frequency interference signals. The receiver response difference between the adjacent channel interference signals and the same frequency interference signals lies in two aspects. On the one hand, the main frequency of the receiving channel coupling and the signal power of the sideband signal injected into the receiver are different. On the other hand, due to the different modulation information of the main frequency and the sideband signal, the signal processing benefits after the signal processing of the receiver are different. The receiver response signal amplitude variation relationship under different adjacent channel interference signals is obtained through the receiver coupling power prediction and the signal processing benefit prediction, the adjacent channel interference signals are converted into response equivalent same frequency interference signals through amplitude equivalence, and the disturbed state of the receiver is predicted based on the sensitive threshold of the same frequency interference signals.

[0027] As shown in Figure 1 , the following steps are included:

[0028] Step S1: Based on the interference signal spectrum, the signal average power of the adjacent channel interference signal with different frequency offsets through the receiving channel coupling is predicted, and the calculation formula is as follows:

[0029]

[0030] Where, P mean (Δf) is the signal average power of the adjacent channel interference signal with a frequency offset of Δf through the receiving channel coupling into the receiver, P(f) is the normalized baseband signal spectrum of the receiver interference signal, and B is the receiver bandwidth. The prediction results of formula (1) for typical narrowband receiver interference signals are shown in Figure 2 .

[0031] Step S2: Predict the processing benefit of the adjacent channel interference signal with different frequency offsets after passing through the receiver signal processing channel;

[0032] The typical receiver signal processing includes pulse compression, pulse accumulation, moving target processing and other processes. The present application takes the same frequency interference signal as a reference, focuses on the benefit difference of the adjacent channel interference signal with different frequency offsets after passing through the signal processing, and obtains the relative benefit of the signal processing of the different adjacent channel interference signals through normalization processing. Therefore, only the signal processing process affected by the frequency offset needs to be concerned.

[0033] For adjacent frequency interference signal, interference signals with different frequency offset are filtered by receiver receiving channel, which mainly affects the signal modulation information, and focuses on the signal processing benefit brought by pulse compression. The pulse compression signal processing benefit prediction is divided into main band and side band according to frequency segmentation, and the pulse compression processing benefit of side band signal is predicted based on signal spectrum, and the calculation formula is:

[0034] G MF (Δf)=P re ,|Δf|>B (2)

[0035] Wherein, G MF (Δf) is pulse compression benefit, P re is the side band signal pulse compression processing benefit correction amount caused by the randomness of signal, which is equal to the average value of the difference between P(Δf) and P mean (Δf) except-2B<Δf<2B.

[0036] The main band is based on theoretical calculation, and the calculation formula is:

[0037]

[0038] Wherein, G MFmax is the pulse compression processing benefit when the interference signal is completely matched with the matched filter, and for example, the linear frequency modulation signal satisfies the power benefit, which is the time pulse width product of the signal:

[0039] G MFmax =10log 10 (B·τ) (4)

[0040] Wherein, τ represents time pulse width.

[0041] The prediction result of pulse compression processing benefit G MF (Δf) of typical receiver interference signal is shown in Figure 3 .

[0042] Step S3: converting the adjacent frequency interference signal into a response equivalent same frequency interference signal through amplitude equivalence.

[0043] Based on the prediction results of step S1 and step S2, the amplitude change relationship of the receiver response signal corresponding to the adjacent frequency interference signal with different frequency offset can be predicted, which can be expressed as: G MF (Δf)+P mean (Δf).

[0044] For the adjacent frequency interference signal with peak power P max and offset frequency Δf, it can be equivalent to the same frequency interference signal with peak power P eq (Δf), which satisfies the formula:

[0045] P eq (Δf)=P max -P G_norm (Δf) (5)

[0046] Wherein, P G_norm (Δf) is G MF (Δf)+P mean (Δf) of the normalized results.

[0047] The prediction result G MF (Δf)+P mean (Δf) of the receiver response signal amplitude corresponding to the adjacent frequency interference signal under different frequency offset amounts directly affects the accuracy of the prediction of the disturbed state of the receiver, the prediction result is compared with the test data of the receiver response signal amplitude of the adjacent frequency interference signal under different frequency offset amounts, the root mean square of the prediction error is calculated, the root mean square of the prediction error is 3.09dB, and the comparison diagram of the prediction result of the typical receiver is as shown in Figure 4 .

[0048] Step S4: predicting the disturbed state of the receiver.

[0049] Step S3: equivalent adjacent frequency interference signals to co-frequency interference signals with peak power P eq (Δf) is obtained, the disturbed state of the receiver under the adjacent frequency interference signal is predicted by comparing P eq (Δf) and the co-frequency interference signal sensitivity threshold P gate .

[0050] When P eq (Δf) is greater than or equal to P gate , the receiver is in a disturbed state.

[0051] When P eq (Δf) is less than P gate , the receiver is in an undisturbed state.

[0052] The receiver disturbed state prediction method for adjacent frequency interference of the same type device of the application is suitable for predicting the receiver response of the signal sideband. In the synchronous working scene of multiple same type receivers, when the center frequency of the interference signal faced by the receiver is offset from the working frequency, the influence of the receiving channel coupling and signal processing is comprehensively considered, the adjacent frequency interference signal is converted into a response equivalent co-frequency interference signal through amplitude equivalence, the disturbed state of the receiver is predicted based on the co-frequency interference signal sensitivity threshold, and the receiver sensitivity threshold under the co-frequency interference can be tested through a practical test.

[0053] It should be noted that the various steps / components described in the present application can be split into more steps / components or two or more steps / components or parts of the operation of steps / components can be combined into new steps / components, as required by implementation, to achieve the objectives of the present application.

[0054] Those skilled in the art will easily understand that the above description is only the preferred embodiment of the present application and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for predicting the interference state of a receiver in the face of adjacent-channel interference from similar devices, characterized in that, include: Based on the interference signal spectrum, predict the average power of adjacent channel interference signals with different frequency offsets coupled through the receiving channel; The processing gain of adjacent channel interference signals with different frequency offsets after passing through the receiver signal processing channel is predicted, and the relative relationship between the processing gain and the frequency offset is obtained. Based on the relative relationship between the average signal power and processing gain and the frequency offset, adjacent channel interference signals are converted into equivalent co-channel interference signals through amplitude equivalence. The interference state of the receiver is predicted based on the sensitivity threshold of the co-channel interference signal.

2. The method according to claim 1, characterized in that, Depend on The average power of adjacent-channel interference signals with different frequency offsets coupled through the receiving channel is predicted, where P mean (Δf) is the average power of the adjacent channel interference signal coupled into the receiver through the receiving channel with a frequency offset of Δf, P(f) is the normalized baseband signal spectrum of the interference signal in the receiver, and B is the receiver bandwidth.

3. The method according to claim 2, characterized in that, The processing gain of the adjacent channel interference signals with predicted frequency offsets after passing through the receiver signal processing channel yields a relative relationship between the processing gain and the frequency offset, including: For adjacent channel interference signals, interference signals with different frequency offsets are filtered by the receiver's receiving channel, affecting the signal processing benefits brought by pulse compression. The pulse compression signal processing benefit prediction is based on frequency segmentation, divided into main frequency band and side band. Therefore, the pulse compression processing benefit of side band signals and the pulse compression processing benefit of main frequency band signals are predicted based on the signal spectrum.

4. The method according to claim 3, characterized in that, By G MF (Δf)=P re ,Δf>B is derived from pulse compression processing of sideband signals based on signal spectrum prediction, where G MF (Δf) represents the pulse compression processing gain, P re The gain correction due to the randomness of the signal during sideband pulse compression processing is equal to P(Δf) and P, except for -2B < Δf < 2B. mean (Δf) is the average of the differences.

5. The method according to claim 4, characterized in that, Depend on The pulse compression processing benefit of the main frequency band is obtained based on theoretical calculations, where G MFmax This benefits from pulse compression processing when the interference signal is perfectly matched with the matched filter.

6. The method according to claim 5, characterized in that, Taking a linear frequency modulated signal as an example, the power gain is equal to the product of the signal's time and pulse widths: G MFmax =10log 10 (B·τ), where τ represents the pulse width.

7. The method according to claim 6, characterized in that, The method of converting adjacent-channel interference signals into equivalent co-channel interference signals through amplitude equivalence, based on the relative relationship between signal average power, processing gain, and frequency offset, includes: Based on the relative relationship between signal average power and processing gain and frequency offset, by G MF (Δf)+P mean (Δf) Predicts the amplitude variation of the receiver response signal corresponding to adjacent channel interference signals with different frequency offsets; For peak power P max The adjacent channel interference signal with an offset frequency of Δf is equivalent to a signal with a peak power of P. eq (Δf) Co-channel interference signal, where P eq (Δf)=P max -P G_norm (Δf), P G_norm (Δf) is G MF (Δf)+P mean The normalized result of (Δf).

8. The method according to claim 7, characterized in that, The prediction of the interference state of the receiver based on the sensitivity threshold of co-channel interference signals includes: By comparing P eq (Δf) and the sensitivity threshold P of co-frequency interference signals gate Predict the receiver's interference state under adjacent channel interference signals, where, when P eq (Δf)≥P gate The receiver is in a disturbed state; when P eq (Δf)<P gate The receiver is in an undisturbed state.

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