CN114401525B - Interference position detection method and system based on narrowband noise energy estimation - Google Patents
Interference position detection method and system based on narrowband noise energy estimation Download PDFInfo
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Abstract
The invention discloses an interference position detection method and system based on narrowband noise energy estimation, wherein the system is used for implementing the method and comprises the following steps: capturing parallel signals of a plurality of narrowband channels, and acquiring received signal energy measurement values and demodulation signal-to-interference-and-noise ratio measurement values of the plurality of narrowband channels in an operating frequency band; independently estimating the received signal energy measurement value of each narrowband channel to obtain an interference detection amount estimation value; screening effective receiving channels according to the measured value of the demodulation signal-to-interference-and-noise ratio and a preset threshold value of the demodulation signal-to-interference-and-noise ratio; setting an energy detection threshold by taking the average value of the energy of the received signals of the selected effective receiving channels as an effective signal energy standard value; detecting whether interference signals exist in each narrowband channel. The invention can simultaneously obtain the received signal energy measurement and the demodulation signal-to-interference-and-noise ratio measurement of a plurality of narrowband channels in the working frequency band, and compared with the scanning type channel detection, the parallel channel detection has higher efficiency.
Description
Technical Field
The invention relates to the technical field of communication signal detection, in particular to an interference position detection method and system based on narrowband noise energy estimation.
Background
In order to realize anti-interference of wireless communication, an interference detection technology is an important link in the field of signal detection, and aims to judge whether interference exists or not and provide necessary prior information for subsequent anti-interference measures.
Typical interference detection techniques include: an energy detection algorithm, a matched filter detection algorithm, a cyclostationary detection method, a covariance matrix decomposition algorithm and the like.
The energy detection algorithm firstly makes two detection assumptions (H1/H0) according to the existence of the interference signal, then calculates the detection statistic of the received signal, compares the detection statistic with a set threshold value, and judges whether the interference signal exists. The energy detection is used as a binary detection method, no priori information of interference signals is needed, and the blind interference detection method is simple, convenient and effective. The energy detection cannot give out the frequency point position of the interference signal and what type of interference belongs to, the influence of background noise is large, and if the noise is unstable, the detection performance is reduced.
And the matched filtering detection algorithm utilizes a linear filter to synchronize with the signal to be detected in the time domain and the frequency domain according to certain priori information of the main user signal, so as to demodulate the main user signal. If the a priori information of the primary user signal is unknown, the detection method is not effective.
The cyclostationary detection method utilizes the cyclostationary characteristic of the signal to detect, the main user signal and the intentional interference signal generally have cyclic frequencies, belong to the cyclostationary signal, have obvious spectrum correlation function amplitude at the non-zero cyclic frequency, and the cyclic frequencies of the main user signal and the intentional interference signal are different. The autocorrelation function of the noise has no periodicity, no cyclostationary property, and its spectral correlation function has a zero amplitude at non-zero cyclic frequencies. Therefore, the detection and separation of the interference signal can be realized by utilizing the characteristic that the cycle frequency of the interference signal is different from that of the main user signal. The method is an effective interference detection algorithm, but the algorithm complexity is too high.
The covariance matrix decomposition algorithm firstly samples a received signal, obtains an autocorrelation function, forms a covariance matrix according to the obtained autocorrelation function, performs characteristic decomposition on the covariance matrix, and obtains a maximum characteristic value lambda max and a minimum characteristic value lambda min. And taking the lambda max/lambda min as detection statistics, if the detection statistics are larger than a threshold value, the main user signal exists, otherwise, the main user signal does not exist. The method is limited to the main user signals with good correlation, and has poor detection effect on independent signals.
The interference detection method has poor recognition effect on the frequency point position of the interference signal, and the energy detection is a signal detection method with wider application range.
There are two disadvantages to pure energy detection: on one hand, the wireless communication system has far-near effect, and the simple energy detection can not effectively distinguish large signals from interference signals, so that interference misjudgment is caused; on the other hand, as binary detection, simple energy detection cannot accurately locate the specific frequency point position of narrowband interference.
Disclosure of Invention
Therefore, the present invention aims to provide a method and a system for detecting an interference position based on narrowband noise energy estimation, which are used for coping with near-far effect of wireless communication, positioning a specific frequency point position of an interference channel in a broadband wireless communication system under the condition of wide fluctuation of received signal energy, and carrying out narrowband noise energy estimation and interference position detection based on a broadband channelized receiver, continuous mean detection amount estimation and a dynamic threshold detection algorithm, thereby obtaining an accurate channel interference detection result.
In order to achieve the above object, the present invention provides an interference position detection method based on narrowband noise energy estimation, comprising the steps of:
Acquiring parallel signals of a plurality of narrowband channels, and acquiring received signal energy measurement values RSSI f and demodulation signal-to-interference-and-noise ratio measurement values SINR f of the plurality of narrowband channels in an operating frequency band;
the received signal energy measurement RSSI f of each narrow-band channel is independently estimated, continuous average filtering is carried out, and the continuous average filtering is used as the interference detection amount estimation value RSSI f _est of the current channel;
Comparing the measured value SINR f of the demodulation signal to interference plus noise ratio with a preset threshold value SINR_thr of the demodulation signal to interference plus noise ratio, and screening effective receiving channels;
Taking the received signal energy average value of the selected effective receiving channel as an effective signal energy standard value RSSI_signal, and setting an energy detection threshold according to the effective signal energy standard value; and comparing the estimated value RSSI f _est of the interference detection quantity in each narrow-band effective receiving channel with an energy detection threshold value to judge whether an interference signal exists.
Further preferably, when screening the valid receiving channels, the method includes comparing the measured value SINR f of the demodulation signal to interference plus noise ratio with a preset threshold value sinr_thr of the demodulation signal to interference plus noise ratio, wherein the channel exceeding the threshold value sinr_thr of the demodulation signal to interference plus noise ratio is used as the valid receiving channel ch_signal, and the receiving channel below the threshold value sinr_thr of the demodulation signal to interference plus noise ratio is the invalid receiving channel ch_ interfer.
Further preferably, the energy detection threshold is a sum of an effective signal energy standard value rssi_signal and a false alarm margin.
Further preferably, the energy detection threshold is calculated according to the following formula:
wherein, RSSI_thr is an energy detection threshold; p fa is the false alarm probability, and the value is 0.001; n is the statistics number of the significant statistics; RSSI_signal is the effective signal energy standard value; the Q function expression is 。
Further preferably, the method for judging whether the interference signal exists comprises the following steps:
Comparing the estimated interference detection value RSSI f _est with a set energy detection threshold, if the estimated interference detection value of the channel interference signal is larger than the energy detection threshold, judging that the channel has an interference signal, and if the estimated interference detection value of a plurality of interference signals is smaller than or equal to the energy detection threshold, judging that the channel has no interference signal.
Further preferably, the method further comprises the step of performing statistical filtering output on the detection result, wherein the statistical filtering output comprises the following steps:
And setting a plurality of detection windows in the detection period, carrying out statistical filtering on the detection results of the plurality of interference and adopting relative statistics to carry out outlier filtering.
Further preferably, when the RSSI f is obtained, the energy is measured by using a time-domain integration or frequency-domain transformation method, where the time-domain integration is to integrate and average the multiple sample values of the received signal; the frequency domain transformation is performed by performing FFT transformation on the received signal, and the energy average value of the narrow-band signal in the frequency domain is used for representing the received signal energy measurement value of the channel.
The invention provides an interference position detection system based on narrowband noise energy estimation, which comprises an AD conversion module, an RSSI measurement module, an RSSI estimation module, an SINR measurement module, a PMF effective channel mask estimation module, a dynamic threshold estimation module and an interference position detection module;
the AD conversion module is used for receiving a broadband wireless signal input by the radio frequency front end and outputting a broadband wireless signal of a digital domain;
The RSSI measuring module is used for carrying out multi-channel parallel energy detection on the broadband wireless signals in the digital domain to obtain received signal energy measurement RSSI f of a plurality of narrowband channels in the working frequency band;
The RSSI estimation module is configured to independently estimate the received signal energy measurement RSSI f of each narrowband channel, and perform continuous average filtering, as an interference detection amount estimation value RSSI f _est of the current channel;
The SINR measuring module is used for measuring the signal-to-interference-and-noise ratio of the low-speed pulse signals input by each channel to obtain a demodulated signal-to-interference-and-noise ratio measuring value SINR f;
The PMF effective channel mask estimation module is configured to compare the measured value SINR f of the demodulation signal-to-interference-and-noise ratio with a preset threshold value sinr_thr of the demodulation signal-to-interference-and-noise ratio, and screen an effective receiving channel;
The dynamic threshold estimation module is used for taking the received signal energy average value of the selected effective receiving channel as an effective signal energy standard value RSSI_signal and setting an energy detection threshold according to the effective signal energy standard value;
And the interference position detection module is used for comparing the estimated value RSSI f _est of the interference detection quantity in each narrow-band effective receiving channel with the energy detection threshold value to judge whether an interference signal exists.
Further preferably, the system further comprises a synchronous acquisition module and a multipath signal extraction module; the synchronous capturing module is used for carrying out sliding autocorrelation on the input broadband wireless signals to obtain the optimal sampling time of each channel and extracting pulse signals of each channel.
The multi-channel signal extraction module is used for extracting the input high-speed digital signals after the optimal sampling time is obtained, and obtaining the low-speed digital signals of each narrow-band channel for subsequent multi-channel signal measurement and estimation.
Further preferably, the system further comprises a statistical filtering module, wherein the statistical filtering module is used for setting a plurality of detection windows in a detection period, performing statistical filtering on the detection results of the plurality of times of interference, and performing outlier filtering by adopting relative statistics.
Compared with the prior art, the method and the system for detecting the interference position based on narrowband noise energy estimation have the following advantages:
1. The interference position detection method and the system based on narrowband noise energy estimation provided by the invention adopt the channelized receiver to capture parallel signals of a plurality of narrowband channels, can simultaneously obtain the received signal energy measurement value and the demodulated signal-to-interference-and-noise ratio measurement value of the plurality of narrowband channels in the working frequency band, and have higher parallel channel detection efficiency compared with scanning type channel detection.
2. Compared with the simple energy detection, the method and the system for detecting the interference position based on the narrowband noise energy estimation have excellent environmental adaptability, can detect the narrowband channel interference under the conditions of no signal, small signal and large signal, and simultaneously give out interference detection and interference position detection results.
3. The invention provides an interference position detection method and system based on narrowband noise energy estimation, wherein a channel exceeding a demodulation signal-to-interference-and-noise ratio threshold value is used as an effective receiving channel, and the average value of the received signal energy of the effective receiving channel and the false alarm probability are used as an interference detection threshold value. Therefore, the dynamic threshold estimator is more accurate than the full frequency domain energy mean value estimation under the condition of narrow-band noise.
Drawings
Fig. 1 is a flow chart of an interference position detection method based on narrowband noise energy estimation according to the present invention.
Fig. 2 is a schematic structural diagram of an interference position detection system based on narrowband noise energy estimation according to the present invention.
Fig. 3 is a flow chart of interference location detection based on narrowband noise energy estimation in an embodiment of the invention.
Fig. 4 is a schematic diagram of narrowband interference position detection of an interference position detection system based on narrowband noise energy estimation according to the present invention.
Detailed Description
The invention is described in further detail below with reference to the drawings and the detailed description.
As shown in fig. 1, the method for detecting an interference position based on narrowband noise energy estimation provided by an embodiment of the present invention includes the following steps:
S1, acquiring parallel signals of a plurality of narrowband channels, and acquiring received signal energy measurement RSSI f and demodulation signal interference and noise ratio measurement SINR f of the plurality of narrowband channels in an operating frequency band;
S2, independently estimating the received signal energy measurement RSSI f of each narrow-band channel, and carrying out continuous mean filtering to obtain an estimated value RSSI f _est of the interference detection quantity of the current channel;
S3, comparing the measured value SINR f of the demodulation signal-to-interference-and-noise ratio with a preset threshold value SINR_thr of the demodulation signal-to-interference-and-noise ratio, and screening an effective receiving channel;
S4, taking the received signal energy average value of the selected effective receiving channel as an effective signal energy standard value RSSI_signal, and setting an energy detection threshold according to the effective signal energy standard value; and comparing the estimated value RSSI f _est of the interference detection quantity in each narrow-band effective receiving channel with an energy detection threshold value to judge whether an interference signal exists.
In S1, parallel signals of a plurality of narrowband channels are acquired, and the parallel signals of the plurality of narrowband channels are captured based on a wideband channelized receiver. The acquiring the received signal energy measurement RSSI f and the demodulation signal to interference and noise ratio measurement SINR f of the plurality of narrowband channels in the operating band specifically includes the following two aspects: a. a received signal energy measurement RSSI f is obtained.
The received signal energy measurement RSSI f of the narrowband channel CH f is an energy measurement of the received signal Y f (t) output by the rf amplification and AD. Alternatively, the energy measurement may be performed by means of time-domain integration or frequency-domain transformation, where the time-domain integration is to integrate and average the multiple sample values of the received signal; the frequency domain transform is performed by FFT-transforming the received signal, and the average value of the energy of the narrowband signal in the frequency domain represents the energy of the received signal of the channel.
The energy detection process of the received signal Y f (t) is formulated as follows:
Y f (t) =s (t) +n (t) +j (t) (formula 1)
(Equation 2)
(Equation 3)
Wherein s (t), n (t) and j (t) are useful signals, background noise and interference signals respectively; l is the number of sampling points, i is the serial number of the sampling points, namely any sampling point; A received signal captured at an arbitrary sampling point i; RSSI f is a received signal energy measurement; when the interference signal j (t) is sufficiently large, the total power of the received signal can be considered to be approximately the interference signal strength.
B. obtaining demodulation signal-to-interference-and-noise ratio the measured values are specifically:
For a digital communication system, signal-to-interference-and-noise ratio measurement can be based on known pulse signal structure information to respectively count signal energy and noise energy, and the ratio of the signal energy to the noise energy is the signal-to-interference-and-noise ratio.
Optionally, the signal-to-interference-and-noise ratio in the frequency hopping communication system is measured as follows:
(equation 4)
Wherein SINR f is a measured value of demodulation signal-to-interference-and-noise ratio counted according to frequency points, E f duty is an energy mean value of pulse occupancy period, E f empty is an energy mean value of pulse idle period, and K is the frequency of occurrence of frequency pulse f in a spectrum detection period.
In S2, the received signal energy measurement RSSI f of each narrowband channel is estimated independently, and continuous average filtering is performed to obtain a relatively stable received signal energy level estimate, which is used as the interference detection amount estimation value RSSI f _est of the current channel.
The interference detection amount estimation is to independently estimate the received signal energy measurement RSSI f of each narrowband channel, and perform continuous average filtering to obtain a relatively stable received signal energy level estimation, which is used as the interference detection amount estimation value RSSI f _est of the current channel.
The estimation process of the channel interference detection quantity is expressed as follows:
(equation 5)
Wherein, RSSI f _est is an interference detection estimated quantity counted according to frequency points, W detect is a detection window length, and N_pulse is the pulse number in each unit detection window; RSSI i f is a received signal energy measurement of the ith pulse of the f-th frequency bin.
S3, screening effective receiving channels according to the measured value SINR f of the demodulation signal-to-interference-and-noise ratio and a preset threshold value SINR_thr of the demodulation signal-to-interference-and-noise ratio.
Preferably, when screening the effective receiving channel, comparing the measured value SINR f of the demodulation signal to interference plus noise ratio with a preset threshold value sinr_thr of the demodulation signal to interference plus noise ratio, wherein a channel exceeding the threshold value sinr_thr of the demodulation signal to noise ratio is used as an effective receiving channel ch_signal, and a receiving channel below the threshold value of the demodulation signal to interference plus noise ratio is an ineffective receiving channel ch_ interfer.
Under the condition of constant envelope modulation, the signal energy mean value of each narrow-band channel is the same, so that the received signal energy mean value of each effective receiving channel can be used as an effective signal energy standard value RSSI_signal.
(Equation 6)
(Equation 7)
Wherein RSSI_signal is an effective signal energy standard value, and F is the total number of frequency point sets in an operating frequency band; PMF f is a mask estimation function used to extract the valid elements within the collection that meet the constraints.
S4, taking the received signal energy average value of the selected effective receiving channel as an effective signal energy standard value RSSI_signal, and setting an energy detection threshold according to the effective signal energy standard value; and comparing the estimated value RSSI f _est of the interference detection quantity in each narrow-band effective receiving channel with an energy detection threshold value to judge whether an interference signal exists.
Further preferably, the energy detection threshold is set as the sum of the effective signal energy standard value rssi_signal and the false alarm margin.
Further preferably, in the actual communication environment, the energy levels of the wireless signal and the background noise may fluctuate, and if the interference detection threshold value is completely dependent on the estimated value of the current signal energy, a false detection problem of a certain probability may occur, that is, the signal and noise energy is greater than the interference detection threshold value. To reduce the false alarm probability (P fa), the interference detection threshold value may be given by the margin value of the false alarm probability, as follows:
the detection threshold is calculated according to the following formula:
(equation 8)
Wherein, RSSI_thr is an energy detection threshold; p fa is the false alarm probability, which is usually taken to be 0.001; n is the statistics number of the significant statistics; RSSI_signal is the effective signal energy standard value; the Q function expression is。
Further preferably, the detecting whether the interference signal exists in each narrowband channel includes: comparing the estimated value RSSI f _est of the interference detection quantity of each narrowband channel with a set detection threshold value to judge whether an interference signal exists or not; and if the energy of the plurality of scrambling signals is larger than the detection threshold, judging that the channel has interference H1, and if the energy of the plurality of scrambling signals is smaller than or equal to the detection threshold, judging that the channel has no interference H0.
The a priori assumption of narrowband channel interference decisions, H1/H0, is as follows:
(equation 9)
Wherein CQIf is an interference position detection result, which indicates whether the f channel has an interference signal.
Further preferably, the method further comprises the step of performing statistical filtering output on the detection result, wherein the statistical filtering output comprises the following steps: and setting a plurality of detection windows in the detection period, and carrying out statistical filtering on the detection results of the plurality of times of interference to filter abnormal detection values.
In order to prevent false detection, a plurality of detection windows are set in the detection period, and the M times of interference detection results are subjected to statistical filtering to filter abnormal detection values, so that the reliability of interference position detection is further ensured.
The statistical filtering adopts relative statistics rel_stat to carry out outlier filtering, and the following formula is adopted:
(equation 10)
(Equation 11)
Where CQI f is the interference location detection output, rel_Stat is the relative statistic, rel_thr is the relative statistic threshold, usually taken as a value of 0.9-1, M is the number of interference detections in the detection period,The detection result of the ith interference detection position is the f interference detection point.
As shown in fig. 2, the invention further provides an interference position detection system based on narrowband noise energy estimation, which comprises an AD conversion module, an RSSI measurement module, an RSSI estimation module, an SINR measurement module, a PMF effective channel mask estimation module, a dynamic threshold estimation module and an interference position detection module;
the AD conversion module is used for receiving a broadband wireless signal input by the radio frequency front end and outputting a broadband wireless signal of a digital domain; AD conversion receives a broadband wireless signal input by the radio frequency front end, and outputs a high-speed digital signal after low-pass filtering and analog-to-digital conversion.
The RSSI measuring module is used for carrying out multi-channel energy detection on the output high-speed digital signals to obtain received signal energy measurement RSSI f of a plurality of narrowband channels in the working frequency band.
The RSSI measuring module carries out multi-channel parallel energy detection on the broadband wireless signal in the digital domain, outputs a multi-channel energy measuring result, and can adopt a time domain integration and frequency domain transformation method for energy measurement.
The RSSI estimation module is used for independently estimating the received signal energy measurement RSSI f of each narrow-band channel, and carrying out continuous average filtering to obtain a stable received signal energy level estimation value which is used as an interference detection amount estimation value RSSI f _est of the current channel;
The synchronous acquisition module performs sliding autocorrelation on the input broadband wireless signal, namely the high-speed digital signal output by the AD conversion module, under the condition of the prior information (spread/frequency hopping synchronous sequence) of the known communication system, so as to obtain the optimal sampling time of each channel and extract the pulse signal of each channel.
And the multipath signal extraction module extracts the input high-speed digital signals at the information rate after the optimal sampling time is obtained, obtains the low-speed digital signals of each narrowband channel, is used for subsequent multipath signal measurement and estimation, and outputs multichannel code element signals.
And the SINR measuring module is used for measuring the signal-to-interference-and-noise ratio of multiple channels of low-speed pulse signals input by the channels to obtain a demodulated signal-to-interference-and-noise ratio measuring value SINR f.
The PMF effective channel mask estimation module is used for screening effective receiving channels according to the demodulation signal-to-interference-and-noise ratio measured value SINR f and a preset demodulation signal-to-interference-and-noise ratio threshold value SINR_thr; and filtering the invalid channels is completed.
The PMF effective channel mask estimation module carries out threshold judgment on the demodulation signal-to-interference-and-noise ratio measured value of each channel, and if SINR f is more than or equal to SINR_thr, the judgment is 1, so that the transmission channel is effective; if SINR f < SINR_thr, the decision is 0, indicating that the transmission channel has no valid signal. SINR f is the demodulated signal-to-interference-and-noise ratio measurement; SINR_thr is a preset demodulation signal-to-interference-and-noise ratio threshold value; the PMF effective channel mask estimation module functions to filter out the ineffective channels for effective signal energy statistics.
The dynamic threshold estimation module is used for setting a detection threshold by taking the received signal energy average value of the selected effective receiving channel as an effective signal energy standard value RSSI_signal; after the PMF invalid channel is filtered, the average value of the received signal energy of each valid receiving channel of the dynamic threshold estimation module is used as an effective signal energy standard value RSSI_signal. To reduce the false alarm probability P fa due to the wireless signal energy fluctuation, the energy detection threshold rssi_thr may be estimated with a margin value of the false alarm probability.
And the interference position detection module is used for detecting whether interference signals exist in each narrowband channel according to the detection threshold value. And in the detection window, the interference position detection module receives detection inputs of an estimated interference detection quantity value RSSI f _est and an energy detection threshold RSSI_thr2 and performs interference judgment.
Further preferably, the device further comprises a statistical filtering module, wherein the statistical filtering module is used for setting a plurality of detection windows in a detection period, performing statistical filtering on the detection results of the plurality of times of interference, and filtering out abnormal detection values. Performing relative statistic estimation on the multiple detection results, and outputting a determined detection result if the relative statistic is greater than a threshold value for removing an abnormal detection value; and outputting a multi-channel interference detection result. The interference position detection system can output a relatively sensitive and reliable interference position detection result through the processing of the measuring module and the filtering module.
Fig. 3 is a flowchart of the detection method and system according to an exemplary embodiment of the present invention, including the following steps:
Detecting whether a statistical filter window is finished or not after starting, if the statistical filter window is Y, detecting for multiple times, and performing statistical filtering; checking whether the channel detection window is ended; if the channel detection window is Y, the dynamic threshold estimation is performed on the interference detection amount estimation value, the interference position detection is implemented, and if the channel detection window is not finished, the following steps are started:
1) Received signal energy measurement
The received signal energy measurement is to perform multi-channel parallel energy detection on the broadband wireless signal in the digital domain and output the received signal energy measurement. The received signal energy measurement may employ time domain integration and frequency domain transformation methods as described in the previous method embodiments.
2) Channel interference detection amount estimation
In the detection window, the channel interference detection quantity estimation carries out continuous average filtering on the energy measurement input by each channel to obtain relatively stable received signal energy level estimation, and the relatively stable received signal energy level estimation is used as an interference detection quantity estimation value RSSI f _est; the channel interference detection amount estimation method is as described in the foregoing method embodiment.
3) Received signal synchronization acquisition
Under the condition of priori information (spread/frequency hopping synchronous sequence) of a known communication system, synchronous acquisition carries out sliding autocorrelation on an input broadband wireless signal, obtains the optimal sampling time of each channel, is used for pulse signal extraction of each channel, and if the signal synchronous acquisition is N, the background noise is taken as a mask estimation threshold value when the synchronous signal is not acquired, and if the signal synchronous acquisition is Y, the acquisition signal is acquired, the multipath signal extraction is carried out.
4) Multipath signal extraction
After the optimal sampling time is obtained, the multipath signals are extracted to extract the input high-speed digital signals at the information rate, and the low-speed digital signals of each narrowband channel are obtained for subsequent multipath signal measurement and estimation.
5) Demodulation signal-to-interference-and-noise ratio measurement
And (3) carrying out signal-to-interference-and-noise ratio measurement on the low-speed pulse signals input by each channel by demodulation signal-to-interference-and-noise ratio measurement, and respectively carrying out statistics on signal energy and noise energy based on known pulse signal structure information, wherein the ratio of the signal energy to the noise energy is the signal-to-interference-and-noise ratio. Alternatively, the demodulation signal-to-interference-and-noise ratio measurement method is as described in the foregoing method embodiment.
6) Effective channel mask PMF estimation
The PMF effective channel mask estimation carries out threshold judgment on the measured value of the demodulation signal-to-interference-and-noise ratio, if SINR f is more than or equal to SINR_thr, the judgment is 1, and the transmission channel is effective; if SINR f < SINR_thr, the decision is 0, indicating that the transmission channel has no valid signal. The PMF effective channel mask estimation module functions to filter out the ineffective channels for effective signal energy statistics.
7) Effective signal energy estimation
After PMF invalid channel filtering, the effective signal energy estimation adopts the received signal energy average value of each effective receiving channel as an effective signal energy standard value RSSI_signal.
8) Dynamic threshold estimation
To reduce the false alarm probability P fa due to the wireless signal energy fluctuation, the energy detection threshold rssi_thr may be estimated with a margin value of the false alarm probability. The dynamic threshold estimation method is as described in the foregoing method embodiment.
9) Interference location detection
In the detection window, when the interference position is detected, detection inputs of an estimated interference detection quantity value RSSIf _est and an energy detection threshold RSSI_thr2 are received, and interference judgment is carried out. The interference position detection method is as described in the foregoing method embodiment.
10 Statistical filtering)
In order to eliminate the problems of interference false detection and false alarm to the greatest extent, the invention also provides a statistical filtering technology, carries out relative statistic estimation on N detection results, and outputs a determined detection result for removing an abnormal detection value if the relative statistic is larger than a threshold value. Statistical filtering methods are described in the method embodiments described above.
The interference position detection system can output a relatively sensitive and reliable interference position detection result through the processing of the measuring module and the filtering module.
As shown in fig. 4, a schematic diagram of detection of a narrowband interference position is shown, in which signals with 3 peaks in dark gray color are detected interference signals, light gray waveforms uniformly below a dotted line are effective signals, and overlapping positions of the interference signals and the effective signals are interference positions.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.
Claims (8)
1. The interference position detection method based on narrowband noise energy estimation is characterized by comprising the following steps of:
Acquiring parallel signals of a plurality of narrowband channels, and acquiring received signal energy measurement values RSSI f and demodulation signal-to-interference-and-noise ratio measurement values SINR f of the plurality of narrowband channels in an operating frequency band;
the received signal energy measurement RSSI f of each narrow-band channel is independently estimated, continuous average filtering is carried out, and the continuous average filtering is used as the interference detection amount estimation value RSSI f _est of the current channel;
Comparing the measured value SINR f of the demodulation signal to interference plus noise ratio with a preset threshold value SINR_thr of the demodulation signal to interference plus noise ratio, and screening effective receiving channels;
Taking the received signal energy average value of the selected effective receiving channel as an effective signal energy standard value RSSI_signal, and setting an energy detection threshold according to the effective signal energy standard value; the energy detection threshold is calculated according to the following formula:
Wherein, RSSI_thr is an energy detection threshold; p fa is a false alarm probability threshold, and the value is 0.001; n is the statistics number of the significant statistics; RSSI_signal is the effective received signal average; the Q function expression is
And comparing the estimated value RSSI f _est of the interference detection quantity in each narrow-band effective receiving channel with an energy detection threshold value to judge whether an interference signal exists.
2. The method of claim 1, wherein the filtering the effective receiving channel includes comparing the measured SINR f with a preset SINR threshold sinr_thr, wherein the receiving channel exceeding the SINR threshold sinr_thr is used as the effective receiving channel ch_signal, and the receiving channel below the snr threshold is the ineffective receiving channel ch_ interfer.
3. The interference location detection method based on narrowband noise energy estimation of claim 1, wherein determining whether an interfering signal is present comprises:
Comparing the estimated interference detection value RSSI f _est with a set energy detection threshold, if the estimated interference detection value of the channel interference signal is larger than the energy detection threshold, judging that the channel has an interference signal, and if the estimated interference detection value of a plurality of interference signals is smaller than or equal to the energy detection threshold, judging that the channel has no interference signal.
4. The method of claim 1, further comprising statistically filtering the detection result, the statistically filtered output comprising the steps of: and setting a plurality of detection windows in the detection period, carrying out statistical filtering on the detection results of the plurality of interference and adopting relative statistics to carry out outlier filtering.
5. The method for detecting interference position based on narrowband noise energy estimation according to claim 1, wherein when the received signal energy measurement RSSI f of a plurality of narrowband channels in the operating band is obtained, energy measurement is performed by using a time domain integration or frequency domain transformation mode, where the time domain integration is to integrate and average a plurality of sample values of the received signal; the frequency domain transformation is performed by performing FFT transformation on the received signal, and the energy average value of the narrow-band signal in the frequency domain is used for representing the received signal energy measurement value of the channel.
6. An interference position detection system based on narrowband noise energy estimation, characterized by comprising an AD conversion module, an RSSI measurement module, an RSSI estimation module, an SINR measurement module, a PMF effective channel mask estimation module, a dynamic threshold estimation module and an interference position detection module for implementing the interference position detection method based on narrowband noise energy estimation according to any of the preceding claims 1-5;
the AD conversion module is used for receiving a broadband wireless signal input by the radio frequency front end and outputting a broadband wireless signal of a digital domain;
The RSSI measuring module is used for carrying out multi-channel parallel energy detection on the broadband wireless signals in the digital domain to obtain received signal energy measurement RSSI f of a plurality of narrowband channels in the working frequency band;
The RSSI estimation module is configured to independently estimate the received signal energy measurement RSSI f of each narrowband channel, and perform continuous average filtering, as an interference detection amount estimation value RSSI f _est of the current channel;
The SINR measuring module is used for measuring the signal-to-interference-and-noise ratio of the low-speed pulse signals input by each channel to obtain a demodulated signal-to-interference-and-noise ratio measuring value SINR f;
The PMF effective channel mask estimation module is configured to compare the measured value SINR f of the demodulation signal-to-interference-and-noise ratio with a preset threshold value sinr_thr of the demodulation signal-to-interference-and-noise ratio, and screen an effective receiving channel;
The dynamic threshold estimation module takes the received signal energy mean value of the selected effective receiving channel as an effective signal energy standard value RSSI_signal, and sets an energy detection threshold according to the effective signal energy standard value;
And the interference position detection module is used for comparing the estimated value RSSI f _est of the interference detection quantity in each narrow-band effective receiving channel with the energy detection threshold value to judge whether an interference signal exists.
7. The narrowband noise energy estimation-based interference location detection system of claim 6, further comprising a synchronization acquisition module and a multipath signal extraction module
The synchronous acquisition module is used for carrying out sliding autocorrelation on the input broadband wireless signals to obtain the optimal sampling time of each channel;
And the multipath signal extraction module is used for extracting the input high-speed digital signals after the optimal sampling time is obtained, obtaining the low-speed digital signals of each narrowband channel and carrying out multipath signal measurement and estimation.
8. The system of claim 6, further comprising a statistical filtering module configured to set a plurality of detection windows in a detection period, perform statistical filtering on the multiple interference detection results, and perform outlier filtering using the relative statistics.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102508210A (en) * | 2011-10-20 | 2012-06-20 | 华中科技大学 | Lightning pulse signal detection and interference resistance device |
| CN103457681A (en) * | 2013-09-03 | 2013-12-18 | 中国电子科技集团公司第五十四研究所 | Method for identifying multipoint cooperation interference in different space positions |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6807405B1 (en) * | 1999-04-28 | 2004-10-19 | Isco International, Inc. | Method and a device for maintaining the performance quality of a code-division multiple access system in the presence of narrow band interference |
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| CN102238111A (en) * | 2010-04-23 | 2011-11-09 | 中兴通讯股份有限公司 | Signal interference detection method and device |
| CN103560864B (en) * | 2013-11-06 | 2017-02-08 | 上海贝岭股份有限公司 | Blind channel self-adaptation method and device |
| CN109274438B (en) * | 2018-09-20 | 2021-09-24 | 扬州万方电子技术有限责任公司 | Self-adaptive double-threshold cooperative interference detection method and device |
| CN109510644B (en) * | 2018-11-23 | 2020-09-08 | 西安电子科技大学 | Direct Spread Communication Signal Interference Detection Method Based on Eye Diagram Energy |
| CN110531168B (en) * | 2019-07-22 | 2021-09-28 | 同方电子科技有限公司 | Pulse signal energy detection system and method based on digital receiver |
| CN112099057B (en) * | 2020-09-17 | 2024-03-05 | 重庆大学 | Double-threshold cooperation GNSS interference detection algorithm based on fuzzy logic |
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-
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102508210A (en) * | 2011-10-20 | 2012-06-20 | 华中科技大学 | Lightning pulse signal detection and interference resistance device |
| CN103457681A (en) * | 2013-09-03 | 2013-12-18 | 中国电子科技集团公司第五十四研究所 | Method for identifying multipoint cooperation interference in different space positions |
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