CN113447893B - Radar pulse signal frequency spectrum automatic detection method, system and medium - Google Patents
Radar pulse signal frequency spectrum automatic detection method, system and medium Download PDFInfo
- Publication number
- CN113447893B CN113447893B CN202111017949.9A CN202111017949A CN113447893B CN 113447893 B CN113447893 B CN 113447893B CN 202111017949 A CN202111017949 A CN 202111017949A CN 113447893 B CN113447893 B CN 113447893B
- Authority
- CN
- China
- Prior art keywords
- channel
- signal
- sub
- frequency
- current
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/28—Details of pulse systems
- G01S7/285—Receivers
Abstract
The invention discloses a method, a system and a medium for automatically detecting a radar pulse signal frequency spectrum, wherein the method comprises the following steps: carrying out digital channelization on the intermediate frequency complex signal to obtain a signal of a sub-channel; carrying out self-adaptive threshold signal detection to obtain effective signals of the sub-channels; respectively carrying out channel crossing judgment on each pair of adjacent sub-channels, and judging the channel crossing condition of the adjacent sub-channels; carrying out digital channelization on the sub-channels without the cross-channel condition, respectively carrying out adaptive threshold signal detection, and then outputting effective signals of the sub-channels of the next stage; and calculating the center frequency and the bandwidth of a corresponding cross-channel broadband signal for the sub-channel with the cross-channel condition, and configuring a corresponding DDS signal generator and a variable bandwidth filter to perform signal matching and detection on the intermediate frequency complex signal. The invention adopts two-stage channelization detection, realizes automatic updating of the noise threshold, and adds the processing of the broadband cross-channel signal, thereby being capable of self-adapting to the bandwidth of the broadband radar signal for detection.
Description
Technical Field
The invention relates to the field of communication, in particular to a method, a system and a medium for automatically detecting a radar pulse signal frequency spectrum.
Background
The radar pulse signal analysis relies on manual work to set a fixed noise threshold for environmental noise estimation for a long time, signals received by a receiver are usually non-cooperative signals, prior information is lacked, so that certain blindness exists in uniform digital channel division, the problem of signal cross-channel exists when radar signals with unknown parameters such as large bandwidth and frequency points are received, the traditional radar pulse signal detection needs to carry out integral processing on a large number of signals, the operation is complex, the real-time performance is poor, and the hardware resource consumption is also large.
In radar reconnaissance, there are two main detection technical schemes at present:
the first is a spectrum detection scheme based on uniform digital channelization, which is shown in fig. 1, and a large instantaneous bandwidth can be divided into a plurality of sub-bands through uniform digital channelization, each sub-band is called a sub-channel, then the output result of each sub-channel is detected and measured, and finally the signal analysis result of the corresponding sub-channel is obtained, the sub-channels with uniform digital channelization have the same bandwidth and the same center frequency interval of the adjacent sub-channels, the output of the sub-channels corresponds to the generated signal frequency points, and the spectrum also corresponds to the corresponding parameters, so that the correctness of the digital channelization is verified. The digital channelized structure successfully separates signals of different frequency points, improves the signal-to-noise ratio of the signals, lays a good foundation for subsequent parameter estimation and signal sorting, is high in calculation efficiency, is easy to realize hardware, and has wide application in actual frequency spectrum sensing of radar signal reconnaissance. However, in the scheme, after detection and judgment, cross-channel signals need to be fused, signals crossing different sub-channels need to be fused during fusion, and under the condition that the number of the cross-channel signals is not determined, fusion modules of a plurality of different sub-channels need to be realized in advance, so that the area of hardware realization is increased, a large amount of resources are consumed, in addition, losses exist after the sub-channels are fused into complete signals, and certain errors are brought to the extraction of subsequent signal parameters;
the second is a frequency spectrum self-adaptive detection scheme based on direct digital down-conversion, filtering and extraction of fast frequency measurement, the detection scheme is shown in fig. 2, the method performs short-time Fourier transform on sampled signals, obtains frequency point and bandwidth information of the corresponding signals through detection, then controls the bandwidths of a digital down-converter and a variable bandwidth filter, and performs matched receiving and detection on the corresponding signals, the structure is simple, and the signals in the monitoring bandwidth can be completely self-adaptively received and detected. However, the processing of the scheme is performed under a high-speed clock, and when a plurality of radar signals exist in the monitoring bandwidth, a plurality of digital down converters and digital filters need to be implemented, so that the processing speed is high, and hardware resources consumed by parallel implementation are huge.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: aiming at the technical problems in the prior art, the invention provides a method, a system and a medium for automatically detecting a radar pulse signal frequency spectrum, which adopt two-stage channelization detection, realize the real-time automatic updating of a noise threshold according to the change of environmental noise, and increase the processing of broadband cross-channel signals, thereby being capable of adaptively detecting the bandwidth of the broadband radar signals.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
a radar pulse signal frequency spectrum automatic detection method comprises the following steps:
s1) receiving the radio frequency signal and converting the radio frequency signal into an intermediate frequency complex signal, and performing digital channelization on the intermediate frequency complex signal to obtain a signal of each subchannel;
s2) respectively carrying out self-adaptive threshold signal detection on the signals of each subchannel to obtain effective signals of each subchannel;
s3) respectively carrying out channel crossing judgment on each pair of adjacent sub-channels according to the data and the parameter information of the effective signals of each sub-channel, and judging the channel crossing condition of the effective signals of each sub-channel;
s4) for the effective signal, the sub-channel without the channel crossing condition exists, the effective signal of the sub-channel is subjected to next-stage digital channelization to obtain the signal of the sub-channel of the next stage, and the signal of the sub-channel of the next stage is respectively subjected to self-adaptive threshold signal detection to obtain the effective signal of the sub-channel of the next stage and output;
for a sub-channel with a channel-crossing condition of an effective signal, calculating the center frequency and the bandwidth of a corresponding channel-crossing broadband signal according to the data of the effective signal of the sub-channel, configuring a corresponding DDS signal generator and a variable bandwidth filter according to the center frequency and the bandwidth of the channel-crossing broadband signal, performing signal matching and detection on an intermediate frequency complex signal by using the DDS signal generator and the variable bandwidth filter, and outputting a matched signal and a detection result.
Further, the adaptive threshold signal detection in step S2) and/or step S4) includes the following steps:
step 1: according to noiseH i Calculating to obtain the initial threshold value of the current sub-channelTh 2 Noise (d) ofH i The noise magnitude of the current sub-channel for no signal input;
step 2: calculating the signal energy value of the current time i of the current sub-channelE k(i) And a peak point of the signal energy difference in the first period including the current time i
According to the peak point of the signal energy difference
Calculating to obtain the current threshold valueTh 1 ；
And step 3: if the signal energy value of the current time i of the current sub-channelE k(i) Is not only larger than the current threshold valueTh 1 And is greater than the initial threshold valueTh 2 If yes, the signal of the current time i of the current sub-channel exists, otherwise, the signal of the current time i of the current sub-channel does not exist;
and 4, step 4: and if the signal corresponding to each moment in the second time period containing the current moment i exists, the signal in the second time period of the current sub-channel is an effective signal, and the step 2 is returned until the detection time is finished.
Further, step 2 specifically includes:
step 2.1: calculating the signal energy value of the current time i of the current sub-channelE k(i) Using a moving smoothing method to measure the signal energy valueE k(i) Noise reduction processing is carried out to obtain an energy value after smoothing processingY k(i) K is the serial number of the current sub-channel;
step 2.2: according to the preset continuous judgment point numberm’Setting a first time interval of a first time period (i-m’,i) And a second time interval (i,i+m’) Respectively calculating a first time interval (i-m’,i) And a second time interval (i,i+m’) Signals per time intervalThe differential level of the time interval is greater than the number of sampling points of the signal rise time of the current sub-channel;
step 2.3: according to a first time interval (i-m’,i) And a second time interval (i,i+m’) Trending of signal energy difference values for each time interval determines signal energy difference peak points
；
Step 2.4: according to the peak value of the signal energy difference
At the moment of timei max Signal energy value of
Calculating the current threshold valueTh 1 。
Further, step 2.3 specifically includes: if the first time interval (i-m’,i) Of the energy difference in each time intervalΔY k(i1) Rising, i1 is the first time interval (i-m’,i) Time of (1), second time interval (i,i+m’) Of the energy difference in each time intervalΔY k(i2) Decrease, i2 is the second time interval (i,i+m’) The signal energy value of the current time iE k(i) Greater than or equal to the initial threshold valueTh 2 The peak value of the signal energy difference
At the moment of timei max Is replaced by the peak value point of the signal energy difference value at the current moment i
Is replaced by the signal energy difference value corresponding to the current moment iΔY k(i) Otherwise, the peak value point of the signal energy difference value
Peak point of difference between present time and signal energy
The value of (c) remains unchanged.
Further, step S3) includes the steps of:
s31) judging whether the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel are overlapped on the time domain, if so, skipping to the step S32), otherwise, skipping to the step S4 if the effective signals of the current sub-channel and the adjacent sub-channel do not have the channel crossing condition);
s32) obtaining effective signal data of the current sub-channel and effective signal data of the adjacent sub-channel, and calculating the effective signal data of the current sub-channel and the adjacent sub-channel according to a power spectrum algorithm to obtain power spectrums corresponding to the effective signals of the current sub-channel and the adjacent sub-channel;
s33) calculating a threshold estimation value according to a preset bandwidth value and a peak value of a power spectrum corresponding to the effective signal, and determining an initial estimation frequency of the effective signal of the current sub-channel according to the threshold estimation value and the power spectrum corresponding to the effective signalindex i _leftAnd cut-off estimation frequencyindex i _rightAnd calculating the initial estimated frequency of the effective signal of the adjacent sub-channelindex i+1 _ leftAnd cut-off estimation frequencyindex i+1 _right；
S34) estimating the frequency from the startindex i _leftCut-off estimation frequencyindex i _rightInitial estimated frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightThe position relation of the sub-channel judging unit judges whether the channel crossing condition exists between the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel.
Further, the power spectrum algorithm in step S32) includes: determining the calculation frequency L according to the pulse length of the effective signal, performing Fourier transform of M points on the data of the effective signal for L times to obtain L frame data, calculating the square of each point of each frame data to obtain the amplitude, then accumulating the amplitude of each point at the corresponding position of each frame data respectively, finally obtaining the power spectrum of the M points after single sub-channel adaptive threshold signal detection and caching the data.
Further, step S34) specifically includes:
calculating the receiving frequency bands of the current sub-channel and the adjacent sub-channel and a transition band between the two sub-channels according to the serial number of the sub-channel, the bandwidth of the sub-channel and the overlapping bandwidth of the adjacent sub-channel;
if the estimated frequency is startedindex i _leftLocated in the frequency band of the current sub-channel and cutting off the estimated frequencyindex i _ rightInitial estimated frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightRespectively located in the transition zone, the effective signals of the current sub-channel have no channel-crossing condition, and the effective signals of the adjacent sub-channels have channel-crossing condition;
if the estimated frequency is startedindex i _leftIn the frequency band of the current sub-channel, cutting off the estimated frequencyindex i _ rightInitial estimated frequencyindex i+1 _leftRespectively located in the transition band, cut-off the estimated frequencyindex i+1 _rightIn the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel both have a channel crossing condition;
if the estimated frequency is startedindex i _leftCut-off estimation frequencyindex i _rightInitial estimated frequencyindex i+1 _leftRespectively located in the transition band, cut-off the estimated frequencyindex i+1 _rightIn the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel has a cross-channel condition, and the effective signal of the adjacent sub-channel has no cross-channel condition;
if the estimated frequency is startedindex i _leftCut-off estimation frequencyindex i _rightIn the frequency band of the current sub-channel, starting to estimate the frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightAnd in the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel do not have the channel crossing condition.
Further, the step S4) of calculating the center frequency and the bandwidth of the corresponding cross-channel wideband signal according to the data of the effective signal of the sub-channel specifically includes: grouping the sub-channels with the channel crossing condition to ensure that the serial numbers of each group of sub-channels are continuous, and calculating the center frequency and the bandwidth of the channel crossing broadband signal corresponding to each group according to the initial estimation frequency of the effective signal of the initial serial number sub-channel in each group and the cut-off estimation frequency of the effective signal of the tail serial number sub-channel.
The invention also provides a system for automatically detecting the frequency spectrum of the radar pulse signal, which comprises computer equipment, wherein the computer equipment is programmed or configured to execute any one of the methods for automatically detecting the frequency spectrum of the radar pulse signal.
The invention also provides a computer readable storage medium, which stores a computer program for executing any one of the methods for automatically detecting the frequency spectrum of the radar pulse signal.
Compared with the prior art, the invention has the advantages that:
1. the method carries out channel crossing judgment on the sub-channels after digital channelization, judges the channel crossing condition of the adjacent sub-channels, respectively processes the sub-channels with the channel crossing condition and the sub-channels without the channel crossing condition, carries out bandwidth matching receiving on the sub-channels with the channel crossing condition, configures the corresponding DDS signal generators and the variable bandwidth filters, retains the complete information of the signals and improves the signal to noise ratio of the signals, and simultaneously reduces the consumption of system resources by judging whether the sub-channels have the channel crossing condition and determining the number of the corresponding DDS signal generators and the variable bandwidth filters;
2. the invention performs adaptive gating of signals in a digital channelized subchannelDetecting limit signal, calculating signal energy difference peak point in real time and calculating current threshold value according to the signal energy difference peak pointTh 1 Therefore, the threshold value is adjusted in real time to determine the effective signal in the sub-channel, the pressure of the system for carrying out subsequent steps is reduced, the subsequent processing is facilitated, and the problem that the adjustment cannot be automatically updated in real time due to the fact that the fixed noise threshold is set for the environmental noise estimation manually in radar pulse signal analysis for a long time is solved.
Drawings
Fig. 1 is a schematic flow chart of a spectrum detection scheme based on uniform digital channelization.
Fig. 2 is a schematic flow chart of a direct digital down-conversion, filtering and decimation-based spectrum adaptive detection scheme based on fast frequency measurement.
FIG. 3 is a flow chart of an embodiment of the present invention.
Fig. 4 is a flowchart of a cross-channel decision of adjacent sub-channels in the embodiment of the present invention.
Fig. 5 is a diagram illustrating the judgment that the valid signal flags of two adjacent sub-channels overlap in the time domain.
Fig. 6 is a diagram illustrating a first cross-channel situation of two adjacent sub-channels.
Fig. 7 is a diagram illustrating a second cross-channel situation of two adjacent sub-channels.
Fig. 8 is a diagram illustrating a third cross-channel situation of two adjacent sub-channels.
Fig. 9 is a diagram illustrating a fourth cross-channel situation between two adjacent sub-channels.
Detailed Description
The invention is further described below with reference to the drawings and specific preferred embodiments of the description, without thereby limiting the scope of protection of the invention.
As shown in fig. 3, the present invention provides an automatic detection method for radar pulse signal spectrum, which includes the following steps:
s1) receiving the radio frequency signal and converting the radio frequency signal into an intermediate frequency complex signal, and performing digital channelization on the intermediate frequency complex signal to obtain a signal of each subchannel;
specifically, in this step, the radio frequency signal is down-converted to obtain an intermediate frequency signal, the intermediate frequency signal is input to an ADC for signal acquisition, most of the acquired signals of the ADC are real signals, and therefore, intermediate frequency real signals are output, then, according to an actual sampling frequency, the intermediate frequency real signals are I/Q converted into intermediate frequency complex signals, the intermediate frequency complex signals are divided into two paths in parallel, one path is digitally channelized, the other path is streamed and cached according to a digital channelization operation time, and in order to measure the broadband pulse signal, in this step, the number of digitally channelized sub-channels is small, the bandwidth of a single sub-channel is large, and the sub-channels can be divided according to actual needs;
s2) respectively carrying out self-adaptive threshold signal detection on the signals of each subchannel to obtain effective signals of each subchannel;
specifically, in this step, each subchannel data after digital channelization is divided into two paths, one path performs adaptive threshold signal detection, the other path performs pipelined cache according to detection time, and parameter information such as frequency point, bandwidth, pulse width and the like of an effective signal of a subchannel can be detected by performing adaptive threshold signal detection on a single subchannel;
s3) respectively carrying out channel crossing judgment on each pair of adjacent sub-channels according to the data and the parameter information of the effective signals of each sub-channel, and judging the channel crossing condition of the effective signals of each sub-channel;
the method comprises the following steps that (1) a narrow-band pulse signal exists in two adjacent sub-channels at the same time, and a wide-band pulse signal exists in a plurality of adjacent sub-channels at the same time, if the narrow-band pulse signal exists in the two adjacent sub-channels at the same time, the carrier frequency, the pulse width and the start-stop time of the pulse signal detected by the two adjacent sub-channels are the same, and the pulse amplitude is different; if the broadband pulse signal exists in a plurality of adjacent sub-channels at the same time, the start and stop time of the pulse signal detected by the plurality of adjacent sub-channels is approximately the same or has time continuity, and the carrier frequencies are different; according to the characteristics, channel crossing judgment is carried out by comparing effective signals detected by each pair of adjacent sub-channels;
s4) for the effective signal, the sub-channel without the channel crossing condition exists, the effective signal of the sub-channel is subjected to next-stage digital channelization to obtain the signal of the sub-channel of the next stage, and the signal of the sub-channel of the next stage is respectively subjected to self-adaptive threshold signal detection to obtain the effective signal of the sub-channel of the next stage and output;
specifically, if the effective signal of the sub-channel does not cross the channel, the data and the parameter information of the effective signal of the sub-channel are directly output together to perform next-stage digital channelization, the next-stage digital channelization supplements the measurement of the narrow-band pulse signal relative to the previous-stage digital channelization, in order to ensure the bandwidth measurement precision requirement of the narrow-band pulse signal, the number of the sub-channels of the next-stage digital channelization is large, the bandwidth of a single sub-channel is small, the sub-channels can be divided according to the actual requirement, the sub-channel data of each next stage after the next-stage digital channelization are also divided into two paths, one path is subjected to adaptive threshold signal detection to obtain the effective signal of the sub-channel of the next stage, and the other path is subjected to pipeline cache according to the detection time; then, outputting the data of the effective signal of the sub-channel of the next stage and the parameter information together, and providing the data of the effective signal and the parameter information such as frequency, bandwidth, pulse width, TOA and the like for subsequent parameter measurement;
for a sub-channel with a channel-crossing condition of an effective signal, calculating the center frequency and the bandwidth of a corresponding channel-crossing broadband signal according to the data of the effective signal of the sub-channel, configuring a corresponding DDS signal generator and a variable bandwidth filter according to the center frequency and the bandwidth of the channel-crossing broadband signal, performing signal matching and detection on an intermediate frequency complex signal by using the DDS signal generator and the variable bandwidth filter, and outputting a matched signal and a detection result;
specifically, if the effective signal of the sub-channel has a cross-channel condition, the sub-channel with the cross-channel condition of the adjacent effective signal is counted, the center frequency and the bandwidth of the cross-channel broadband signal can be calculated according to the data of the effective signal, parameter information is provided for a DDS signal generator and a variable bandwidth filter designed for digital down-conversion, the number of the DDS signal generator and the variable bandwidth filter can be set to the maximum according to the actual application scene and the resource consumption condition, the cut-off frequency of the variable bandwidth filter can be set through the bandwidth of the cross-channel broadband signal to perform bandwidth matching on the signal, the complete information of the required signal is reserved, the signal to noise ratio of the signal is improved, data output by each variable bandwidth filter is divided into two paths, 1 path is used for filtering signal detection, the 1 path is used for performing flow caching according to the filtering detection running time, and finally, the data of the matched signal and the filtering detection result are output together to perform subsequent parameter measurement.
Through the above steps, the present embodiment performs channel crossing decision for the sub-channels after digital channelization, determines the channel crossing condition of the effective signals of the adjacent sub-channels, processes the sub-channels with the channel crossing condition for the effective signals and the sub-channels without the channel crossing condition for the effective signals, performs bandwidth matching reception for the DDS signal generator and the variable bandwidth filter corresponding to the sub-channel configuration with the channel crossing condition for the effective signals, retains the complete information of the required signals and improves the signal to noise ratio of the signals, determines the number of the sub-channels with the channel crossing condition for the effective signals by determining the channel crossing condition for the effective signals of the adjacent sub-channels, and simultaneously configures the DDS signal generator and the variable bandwidth filter corresponding to the sub-channels with the channel crossing condition for the effective signals, thereby reducing system resource consumption
Considering that radar signals are mainly pulse signals, unstable ultrashort pulses need to be removed in signal detection, jitter and burrs are eliminated, long pulses are marked, and subsequent processing is facilitated. Meanwhile, because the radar signal sampling frequency is high, the data rate is high, the number of sub-channels to be judged is large, the data volume is large, the noise floor difference between different sub-channels is large, and a judgment algorithm which is simple, quick, high in detection performance and good in realizability is needed. Based on the above requirement, in this embodiment, the adaptive threshold signal detection is performed on the sub-channel signals in step S2) and step S4) to determine valid signals and eliminate invalid signals, and the adaptive threshold signal detection performed in step S2) and/or step S4) includes the following steps:
step 1: obtaining noise magnitude of current sub-channel under condition of no signal inputH i According to noiseH i Calculating to obtain an initial threshold valueTh 2 In this embodimentTh 2 =4H i ；
Step 2: calculating the signal energy value of the current time i of the current sub-channelE k(i) And a peak point of the signal energy difference in the first period including the current time i
According to the peak point of the signal energy difference
Calculating to obtain the current threshold valueTh 1 The method specifically comprises the following steps:
step 2.1: calculating the signal energy value of the current time i of the current sub-channelE k(i) Using a moving smoothing method to measure the signal energy valueE k(i) Noise reduction processing is carried out to obtain an energy value after smoothing processingY k(i) The function is expressed as follows:
in the above formula, m is the number of smooth points, k is the serial number of the current sub-channel, and i is the current time;
step 2.2: according to the preset continuous judgment point numberm’Setting a first time interval of a first time period (i-m’,i) And a second time interval (i,i+m’) Respectively calculating a first time interval (i-m’,i) And a second time interval (i,i+m’) The signal energy difference value of each time interval, the difference grade of the time interval is greater than the number of sampling points of the signal rise time of the current sub-channel;
energy difference value corresponding to current subchannel i' momentΔY k(i') The function of (a) is expressed as follows:
in the above formula, the first and second carbon atoms are,Y k(i') is as followsThe energy value of the previous subchannel i' after time smoothing,Y k(i'+n) the energy value after the smoothing processing of the current sub-channel i' + n time is obtained, k is the serial number of the current sub-channel, and n is the differential stage number;
step 2.3: according to a first time interval (i-m’,i) And a second time interval (i,i+m’) Trending of signal energy difference values for each time interval determines signal energy difference peak points
；
Specifically, if the first time interval (i-m’,i) Of the energy difference in each time intervalΔY k(i1) Rising, i1 is the first time interval (i-m’,i) Time of (1), second time interval (i,i+m’) Of the energy difference in each time intervalΔY k(i2) Decrease, i2 is the second time interval (i,i+m’) The signal energy value of the current time iE k(i) Greater than or equal to the initial threshold valueTh 2 The peak value of the signal energy difference
At the moment of timei max Is replaced by the current time i, i.e.i max =iPeak point of signal energy difference
Is replaced by the signal energy difference value corresponding to the current moment iΔY k(i) I.e. by
=ΔY k(i) Otherwise, the peak value point of the signal energy difference value
At the moment of timei max Sum signal energy difference peak point
The value of (d) remains unchanged;
step 2.4: according to the peak value of the signal energy difference
At the moment of timei max Signal energy value of
Calculating the current threshold valueTh 1 The function is expressed as follows:
in the above formula, the first and second carbon atoms are,
for signal energy difference peak point
At the moment of timei max Next, the signal energy value of the current subchannel;
and step 3: if the signal energy value of the current time i of the current sub-channelE k(i) Is not only larger than the current threshold valueTh 1 And is greater than the initial threshold valueTh 2 If yes, the signal of the current time i of the current sub-channel exists, otherwise, the signal of the current time i of the current sub-channel does not exist;
and 4, step 4: if the signal corresponding to each moment in the second time interval containing the current moment i exists, the signal in the second time interval of the current sub-channel is an effective signal, and an effective signal zone bit is marked for the effective signalvaild_iReturning to step 2 until the detection time is over, in order to reduce the probability of erroneous determination, in this embodiment, it is necessary to determine whether there are 5 consecutive time signals, so that in this embodiment, the second time period includes 5 consecutive times including the current time i.
As shown in fig. 4, step S3) of the present embodiment includes the steps of:
s31) judging whether the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel are overlapped on the time domain, if so, skipping to the step S32), otherwise, skipping to the step S4 if the effective signals of the current sub-channel and the adjacent sub-channel do not have the channel crossing condition);
specifically, each subchannel of the digital channelization may have a part of bandwidth overlap, and the start and stop times of signals detected by each subchannel should be substantially the same or have time continuity according to the fact that the wideband pulse signal exists in a plurality of adjacent subchannels at the same time, based on the two points, this embodiment first determines whether there is an overlap condition of effective signals output by two adjacent subchannels on a time axis, if there is a cross-channel condition of the wideband signal, there is an overlap condition of effective signals of two adjacent subchannels on a time axis, otherwise, there is no cross-channel condition;
the specific overlap judgment situation is shown in fig. 5, where the flag bit of the valid signal of the current sub-channel isvaild_iThe pulse width parameter ispulse_i，pulse_i=TOE_i-TOA_iWhereinTOE_iIs the off-time of the pulse of the active signal of the current sub-channel,TOA_ithe starting time of the effective signal of the current sub-channel is corresponding to the flag bit of the effective signal of the adjacent sub-channelvaild_i+1The pulse width parameter ispulse_i+ 1，pulse_i+1=TOE_i+1-TOA_i+1WhereinTOE_i+1Is the off-time of the pulse of the active signal of the adjacent sub-channel,TOA_i+1for the starting time of the effective signals of the adjacent sub-channels, the effective signals of the current sub-channel on the left side and the effective signals of the adjacent sub-channels are overlapped on the time domain, so that the effective signals of the current sub-channel and/or the effective signals of the adjacent sub-channels have a channel crossing condition, and the effective signals of the current sub-channel on the right side and the effective signals of the adjacent sub-channels do not overlap on the time domain, so that the effective signals of the current sub-channel and the effective signals of the adjacent sub-channels do not have a channel crossing condition;
s32) obtaining effective signal data of the current sub-channel and effective signal data of the adjacent sub-channel, and calculating the effective signal data of the current sub-channel and the adjacent sub-channel according to a power spectrum algorithm to obtain power spectrums corresponding to the effective signals of the current sub-channel and the adjacent sub-channel;
the rate spectrum algorithm of the present embodiment includes: performing Fourier transform of M points on the data of the effective signal for L times to obtain L frame data, wherein the calculation times L are determined according to the pulse length of the effective signal, and the function expression is as follows:
in the above formula, the first and second carbon atoms are,pulse_i’m is the number of the middle points of Fourier transform;
the amplitude is calculated for each point square of each frame datasquare i’ (k’,n’)，i'A sub-channel number is indicated and,k’∈ (1,L)the number of fourier transforms is represented as,n’∈(1,M)representing the serial number of the midpoint in Fourier transform, then accumulating the amplitude of each point at the corresponding position of each frame data respectively, and finally obtaining the power spectrum of the M points after single sub-channel adaptive threshold signal detectionadd_square i’ (n’)Caching the data;
s33) calculating a threshold estimation value according to a preset bandwidth value and a peak value of a power spectrum corresponding to the effective signal, and determining an initial estimation frequency of the effective signal of the current sub-channel according to the threshold estimation value and the power spectrum corresponding to the effective signalindex i _leftAnd cut-off estimation frequencyindex i _rightAnd calculating the initial estimated frequency of the effective signal of the adjacent sub-channelindex i+1 _ leftAnd cut-off estimation frequencyindex i+1 _right；
Specifically, the bandwidth value in this embodiment is 3dBIndicates that the signal amplitude differs from the maximum by 3dBThe corresponding frequency bandwidth and the corresponding power represent the frequency range corresponding to the half difference between the signal power and the maximum power, and the power spectrum corresponding to the effective signal of the current sub-channeladd_square i (n)Traversing search to find power spectrum peakadd_square i (n) max Then, the functional expression of the threshold estimation value when the power is halved at this time is:
in the above formula, the first and second carbon atoms are,add_square i (n) max the peak value of the power spectrum corresponding to the effective signal of the current sub-channel is obtained;
based on a threshold estimatepower_th i Power spectrum corresponding to effective signaladd_square i (n)A power spectrum can be foundadd_square i (n)The left and right positions corresponding to the half-subtracted maximum value are respectively recorded as the initial estimation frequency of the effective signal of the current sub-channelindex i _leftThe cutoff estimation frequency of the current sub-channel effective signalindex i _right；
The initial estimated frequency of the effective signal of the adjacent sub-channel can be obtained by the same methodindex i+1 _leftAnd cut-off estimation frequencyindex i+1 _right；
S34) estimating the frequency from the startindex i _leftCut-off estimation frequencyindex i _rightInitial estimated frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightThe determining whether the channel-crossing condition exists between the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel includes:
specifically, in this embodiment, the receiving frequency band of the sub-channel is determined by the bandwidth of the sub-channel and the receiving center frequency, and the function expression of the receiving center frequency is:
in the above formula, the first and second carbon atoms are,BWfor the bandwidth of each sub-channel,BW _sharei is the overlapping bandwidth of adjacent sub-channels, and i is the serial number of the sub-channel;
then, a transition zone between the two sub-channels is calculated, and the frequency interval of the transition zone is:
in the above formula, the first and second carbon atoms are,BWfor the bandwidth of each sub-channel,BW _sharei is the overlapping bandwidth of adjacent sub-channels, and i is the serial number of the sub-channel;
after obtaining the receiving frequency bands of the current sub-channel and the adjacent sub-channel and the transition band between the two sub-channels, the position relationship between the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel can be determined, so as to determine the cross-channel condition, in this embodiment, the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel have the following four conditions:
as shown in fig. 6, the effective signal of the current sub-channel partially falls in the transition band, and the effective signals of the adjacent sub-channels all fall in the transition band, so that the effective signal of the current sub-channel is considered to have no cross-channel condition, but the effective signals of the adjacent sub-channels have cross-channel condition, that is, if the frequency is initially estimatedindex i _leftLocated in the frequency band of the current sub-channel and cutting off the estimated frequencyindex i _rightInitial estimated frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightRespectively located in the transition zone, the effective signals of the current sub-channel have no channel-crossing condition, and the effective signals of the adjacent sub-channels have channel-crossing condition;
as shown in fig. 7, the effective signal portion frequency of the current sub-channel falls in the transitionThe effective signal part frequency of the adjacent sub-channel falls in the transition zone, so that the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel are considered to have a channel crossing condition, namely if the frequency is initially estimatedindex i _leftIn the frequency band of the current sub-channel, cutting off the estimated frequencyindex i _rightInitial estimated frequencyindex i+1 _leftRespectively located in the transition band, cut-off the estimated frequencyindex i+1 _rightIn the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel both have a channel crossing condition;
as shown in fig. 8, all frequencies of the effective signals of the current sub-channel fall in the transition band, and at the same time, some frequencies of the effective signals of the adjacent sub-channels fall in the transition band, so that the effective signals of the current sub-channel are considered to have a cross-channel condition, but the effective signals of the adjacent sub-channels do not have a cross-channel condition, that is, if the frequency is initially estimatedindex i _leftCut-off estimation frequencyindex i _rightInitial estimated frequencyindex i+1 _leftRespectively located in the transition band, cut-off the estimated frequencyindex i+1 _rightIn the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel has a cross-channel condition, and the effective signal of the adjacent sub-channel has no cross-channel condition;
as shown in fig. 9, all frequencies of the effective signals of the current sub-channel do not fall in the transition zone, and all frequencies of the effective signals of the adjacent sub-channels do not fall in the transition zone, so that it is considered that there is no cross-channel condition between the effective signals of the current sub-channel and the effective signals of the adjacent sub-channels, that is, if the frequency is initially estimatedindex i _leftCut-off estimation frequencyindex i _rightIn the frequency band of the current sub-channel, starting to estimate the frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightIn the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel do not have the cross-channel conditionThe method is described.
The step S4) of determining a channel-crossing condition for the effective signal determined for each pair of adjacent sub-channels, and for the sub-channel in which the effective signal has the channel-crossing condition, calculating the center frequency and the bandwidth of the corresponding channel-crossing wideband signal according to the data of the effective signal of the sub-channel specifically includes:
grouping the sub-channels with the channel crossing condition to ensure that the serial numbers of each group of sub-channels are continuous;
for example, the subchannel numbers in the cross-lane case are: i-b, … …, i + c, i + d, … … and i + f, wherein serial numbers i-b to i + c are continuous, serial numbers i + c and i + d are discontinuous, and serial numbers i + d to i + f are continuous, so that the two groups are divided into two groups, namely serial numbers i-b to i + c of sub-channels in the first group and serial numbers i + d to i + f of sub-channels in the second group;
calculating the center frequency and the bandwidth of the cross-channel broadband signal corresponding to each group according to the starting estimation frequency of the starting sequence number sub-channel effective signal and the cut-off estimation frequency of the tail sequence number sub-channel effective signal in each group;
for example, the bandwidth function expression of the first set of corresponding cross-channel wideband signals is:
in the above formula, the first and second carbon atoms are,index i-b _leftthe frequency is estimated for the start of the start sequence number subchannel valid signal in the first group,index i+c _rightthe estimated frequency is the cut-off for the last sequence number subchannel valid signal in the first group,BWis the bandwidth of the sub-channel and,BW/Mrepresenting the frequency resolution, i-b is the initial subchannel serial number in the first group, and i + c is the tail subchannel serial number in the first group;
the first set of corresponding cross-channel wideband signals have a center frequency function expression as follows:
in the above formula, the first and second carbon atoms are,index i-b _leftthe frequency is estimated for the start of the start sequence number subchannel valid signal in the first group,index i+c _rightthe estimated frequency is the cut-off for the last sequence number subchannel valid signal in the first group,BWis the bandwidth of the sub-channel and,BW/Mindicating the frequency resolution, i-b the starting subchannel number in the first group, i + c the last subchannel number in the first group.
The method of the embodiment obtains the effective signal through the detection of the sub-channel signal, performs the cross-channel analysis of the effective signal and performs the variable bandwidth filtering design on the sub-channel of the effective signal with the cross-channel condition, thereby solving the problem of the fusion of the cross-channel signal, simultaneously properly saving the DDS signal generator used for digital down conversion and the number of the variable bandwidth filtering, reducing the consumption of system resources, and solving the problems that the radar pulse signal analysis sets the fixed noise threshold by the manual estimation of the environmental noise for a long time and the threshold can not be automatically updated and adjusted in real time through the self-adaptive threshold signal detection.
The embodiment also provides a system for automatically detecting the radar pulse signal spectrum, which comprises a computer device, wherein the computer device is programmed or configured to execute the method for automatically detecting the radar pulse signal spectrum.
The embodiment also provides a computer-readable storage medium, which stores a computer program for executing the method for automatically detecting the frequency spectrum of the radar pulse signal.
The foregoing is considered as illustrative of the preferred embodiments of the invention and is not to be construed as limiting the invention in any way. Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.
Claims (8)
1. A radar pulse signal frequency spectrum automatic detection method is characterized by comprising the following steps:
s1) receiving the radio frequency signal and converting the radio frequency signal into an intermediate frequency complex signal, and performing digital channelization on the intermediate frequency complex signal to obtain a signal of each subchannel;
s2) respectively carrying out self-adaptive threshold signal detection on the signals of each subchannel to obtain effective signals of each subchannel;
s3) performing channel crossing decision on each pair of adjacent sub-channels according to the data and parameter information of the effective signal of each sub-channel, and determining the channel crossing condition of the effective signal of each sub-channel, including the following steps:
s31) judging whether the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel are overlapped on the time domain, if so, skipping to the step S32), otherwise, skipping to the step S4 if the effective signals of the current sub-channel and the adjacent sub-channel do not have the channel crossing condition);
s32) obtaining effective signal data of the current sub-channel and effective signal data of the adjacent sub-channel, and calculating the effective signal data of the current sub-channel and the adjacent sub-channel according to a power spectrum algorithm to obtain power spectrums corresponding to the effective signals of the current sub-channel and the adjacent sub-channel;
s33) calculating a threshold estimation value according to a preset bandwidth value and a peak value of a power spectrum corresponding to the effective signal, and determining an initial estimation frequency of the effective signal of the current sub-channel according to the threshold estimation value and the power spectrum corresponding to the effective signalindex i _leftAnd cut-off estimation frequencyindex i _rightAnd calculating the initial estimated frequency of the effective signal of the adjacent sub-channelindex i+1 _leftAnd cut-off estimation frequencyindex i+1 _right；
S34) estimating the frequency from the startindex i _leftCut-off estimation frequencyindex i _rightInitial estimated frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightJudging whether the channel crossing condition exists between the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel or not according to the position relation;
s4) for the effective signal, the sub-channel without the channel crossing condition exists, the effective signal of the sub-channel is subjected to next-stage digital channelization to obtain the signal of the sub-channel of the next stage, and the signal of the sub-channel of the next stage is respectively subjected to self-adaptive threshold signal detection to obtain the effective signal of the sub-channel of the next stage and output;
for a sub-channel with a channel-crossing condition of an effective signal, calculating the center frequency and the bandwidth of a corresponding channel-crossing broadband signal according to the data of the effective signal of the sub-channel, configuring a corresponding DDS signal generator and a variable bandwidth filter according to the center frequency and the bandwidth of the channel-crossing broadband signal, performing signal matching and detection on an intermediate frequency complex signal by using the DDS signal generator and the variable bandwidth filter, and outputting a matched signal and a detection result;
the step S2) and/or the step S4) of performing the adaptive threshold signal detection includes the steps of:
step 1: according to noiseH i Calculating to obtain the initial threshold value of the current sub-channelTh 2 Noise (d) ofH i The noise magnitude of the current sub-channel for no signal input;
step 2: calculating the signal energy value of the current time i of the current sub-channelE k(i) For signal energy valueE k(i) Obtaining an energy value after smoothingY k(i) According to the energy valueY k(i) Calculating the peak value point of the signal energy difference value in the first period containing the current time i
According to the signal energy difference peak point satisfying the condition
Calculating to obtain the current threshold valueTh 1 ；
And step 3: if the signal energy value of the current time i of the current sub-channelE k(i) Is not only larger than the current threshold valueTh 1 And is greater than the initial threshold valueTh 2 If yes, the signal of the current time i of the current sub-channel exists, otherwise, the signal of the current time i of the current sub-channel does not exist;
and 4, step 4: and if the signal corresponding to each moment in the second time period containing the current moment i exists, the signal in the second time period of the current sub-channel is an effective signal, and the step 2 is returned until the detection time is finished.
2. The method for automatically detecting the frequency spectrum of the radar pulse signal according to claim 1, wherein the step 2 specifically comprises:
step 2.1: calculating the signal energy value of the current time i of the current sub-channelE k(i) Using a moving smoothing method to measure the signal energy valueE k(i) Noise reduction processing is carried out to obtain an energy value after smoothing processingY k(i) K is the serial number of the current sub-channel;
step 2.2: according to the preset continuous judgment point numberm’Setting a first time interval of a first time period (i-m’,i) And a second time interval (i,i+m’) Respectively calculating a first time interval (i-m’,i) And a second time interval (i,i+m’) The signal energy difference value of each time interval, the difference grade of the time interval is greater than the number of sampling points of the signal rise time of the current sub-channel;
step 2.3: according to a first time interval (i-m’,i) And a second time interval (i,i+m’) Trending of signal energy difference values for each time interval determines signal energy difference peak points
；
Step 2.4: according to the peak value of the signal energy difference
At the moment of timei max Signal energy value of
Calculating the current threshold valueTh 1 。
3. The method for automatically detecting the radar pulse signal spectrum according to claim 2, wherein the step 2.3 specifically comprises: if the first time interval (i-m’,i) Of the energy difference in each time intervalΔY k(i1) Rising, i1 is the first time interval (i-m’,i) Time of (1), second time interval (i,i+m’) Of the energy difference in each time intervalΔY k(i2) Decrease, i2 is the second time interval (i,i+m’) The signal energy value of the current time iE k(i) Greater than or equal to the initial threshold valueTh 2 The peak value of the signal energy difference
At the moment of timei max Is replaced by the peak value point of the signal energy difference value at the current moment i
Is replaced by the signal energy difference value corresponding to the current moment iΔY k(i) Otherwise, the peak value point of the signal energy difference value
Peak point of difference between present time and signal energy
The value of (c) remains unchanged.
4. The method for automatically detecting the spectrum of a radar pulse signal according to claim 1, wherein the power spectrum algorithm in step S32) comprises: determining the calculation frequency L according to the pulse length of the effective signal, performing Fourier transform of M points on the data of the effective signal for L times to obtain L frame data, calculating the square of each point of each frame data to obtain the amplitude, then accumulating the amplitude of each point at the corresponding position of each frame data respectively, finally obtaining the power spectrum of the M points after single sub-channel adaptive threshold signal detection and caching the data.
5. The method for automatically detecting the spectrum of a radar pulse signal according to claim 1, wherein step S34) specifically includes:
calculating the receiving frequency bands of the current sub-channel and the adjacent sub-channel and a transition band between the two sub-channels according to the serial number of the sub-channel, the bandwidth of the sub-channel and the overlapping bandwidth of the adjacent sub-channel;
if the estimated frequency is startedindex i _leftLocated in the frequency band of the current sub-channel and cutting off the estimated frequencyindex i _rightInitial estimated frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightRespectively located in the transition zone, the effective signals of the current sub-channel have no channel-crossing condition, and the effective signals of the adjacent sub-channels have channel-crossing condition;
if the estimated frequency is startedindex i _leftIn the frequency band of the current sub-channel, cutting off the estimated frequencyindex i _rightInitial estimated frequencyindex i+1 _leftRespectively located in the transition band, cut-off the estimated frequencyindex i+1 _rightIn the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel both have a channel crossing condition;
if the estimated frequency is startedindex i _leftCut-off estimation frequencyindex i _rightInitial estimated frequencyindex i+1 _ leftRespectively located in the transition band, cut-off the estimated frequencyindex i+1 _rightIn the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel has a cross-channel condition, and the effective signal of the adjacent sub-channel has no cross-channel condition;
if the estimated frequency is startedindex i _leftCut-off estimation frequencyindex i _rightIn the frequency band of the current sub-channel, starting to estimate the frequencyindex i+1 _leftCut-off estimation frequencyindex i+1 _rightAnd in the frequency band of the adjacent sub-channel, the effective signal of the current sub-channel and the effective signal of the adjacent sub-channel do not have the channel crossing condition.
6. The method of claim 1, wherein the step S4) of calculating the center frequency and the bandwidth of the corresponding cross-channel wideband signal according to the data of the effective signal of the sub-channel specifically comprises: grouping the sub-channels with the channel crossing condition to ensure that the serial numbers of each group of sub-channels are continuous, and calculating the center frequency and the bandwidth of the channel crossing broadband signal corresponding to each group according to the initial estimation frequency of the effective signal of the initial serial number sub-channel in each group and the cut-off estimation frequency of the effective signal of the tail serial number sub-channel.
7. An automatic radar pulse signal spectrum detection system comprising a computer device, wherein the computer device is programmed or configured to perform the automatic radar pulse signal spectrum detection method of any one of claims 1 to 6.
8. A computer-readable storage medium, wherein the computer-readable storage medium stores a computer program for executing the method for automatically detecting a radar pulse signal spectrum according to any one of claims 1 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111017949.9A CN113447893B (en) | 2021-09-01 | 2021-09-01 | Radar pulse signal frequency spectrum automatic detection method, system and medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111017949.9A CN113447893B (en) | 2021-09-01 | 2021-09-01 | Radar pulse signal frequency spectrum automatic detection method, system and medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113447893A CN113447893A (en) | 2021-09-28 |
| CN113447893B true CN113447893B (en) | 2021-12-24 |
Family
ID=77819283
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111017949.9A Active CN113447893B (en) | 2021-09-01 | 2021-09-01 | Radar pulse signal frequency spectrum automatic detection method, system and medium |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113447893B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115396079B (en) * | 2022-07-15 | 2023-12-01 | 湖南艾科诺维科技有限公司 | Multichannel channelizing method based on FPGA |
| CN116819185B (en) * | 2023-08-29 | 2023-11-24 | 南京航天工业科技有限公司 | Digital phase discrimination method and system based on channelization in complex electromagnetic environment |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4093948A (en) * | 1976-06-08 | 1978-06-06 | Westinghouse Electric Corp. | Target detection in a medium pulse repetition frequency pulse doppler radar |
| US5327142A (en) * | 1992-10-01 | 1994-07-05 | The United States Of America As Represented By The Secretary Of The Air Force | Frequency encoding circuit in Bragg cell receiver |
| CN102355273A (en) * | 2011-08-17 | 2012-02-15 | 清华大学 | Digital channelizing method and circuit |
| CN103718060A (en) * | 2011-07-21 | 2014-04-09 | 波音公司 | Radar pulse detection using a digital radar receiver |
| CN104168036A (en) * | 2014-07-21 | 2014-11-26 | 中国电子科技集团公司第四十一研究所 | Multistage digital channelization receiver |
| CN106707247A (en) * | 2017-03-24 | 2017-05-24 | 武汉大学 | High-frequency ocean radar target detection method based on compact antenna array |
| CN106896346A (en) * | 2017-03-13 | 2017-06-27 | 中国电子科技集团公司第三十八研究所 | A kind of low signal-to-noise ratio Complex Radar pulse envelope signal detecting method and device |
| CN109196832A (en) * | 2016-07-07 | 2019-01-11 | 松下电器（美国）知识产权公司 | Sending device, reception device, sending method and method of reseptance |
| CN110632563A (en) * | 2019-09-06 | 2019-12-31 | 北京理工大学 | Intra-pulse frequency coding signal parameter measuring method based on short-time Fourier transform |
| CN113259024A (en) * | 2021-05-31 | 2021-08-13 | 中国人民解放军空军预警学院 | Threshold prediction adjustment method for amplitude of digital channelized receiver |
-
2021
- 2021-09-01 CN CN202111017949.9A patent/CN113447893B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4093948A (en) * | 1976-06-08 | 1978-06-06 | Westinghouse Electric Corp. | Target detection in a medium pulse repetition frequency pulse doppler radar |
| US5327142A (en) * | 1992-10-01 | 1994-07-05 | The United States Of America As Represented By The Secretary Of The Air Force | Frequency encoding circuit in Bragg cell receiver |
| CN103718060A (en) * | 2011-07-21 | 2014-04-09 | 波音公司 | Radar pulse detection using a digital radar receiver |
| CN102355273A (en) * | 2011-08-17 | 2012-02-15 | 清华大学 | Digital channelizing method and circuit |
| CN104168036A (en) * | 2014-07-21 | 2014-11-26 | 中国电子科技集团公司第四十一研究所 | Multistage digital channelization receiver |
| CN109196832A (en) * | 2016-07-07 | 2019-01-11 | 松下电器（美国）知识产权公司 | Sending device, reception device, sending method and method of reseptance |
| CN106896346A (en) * | 2017-03-13 | 2017-06-27 | 中国电子科技集团公司第三十八研究所 | A kind of low signal-to-noise ratio Complex Radar pulse envelope signal detecting method and device |
| CN106707247A (en) * | 2017-03-24 | 2017-05-24 | 武汉大学 | High-frequency ocean radar target detection method based on compact antenna array |
| CN110632563A (en) * | 2019-09-06 | 2019-12-31 | 北京理工大学 | Intra-pulse frequency coding signal parameter measuring method based on short-time Fourier transform |
| CN113259024A (en) * | 2021-05-31 | 2021-08-13 | 中国人民解放军空军预警学院 | Threshold prediction adjustment method for amplitude of digital channelized receiver |
Non-Patent Citations (2)
| Title |
|---|
| Reinforcement Learning-Based Joint Adaptive Frequency Hopping and Pulse-Width Allocation for Radar anti-Jamming;Ailiya et al.;《2020 IEEE Radar Conference》;20201231;第1-6页 * |
| 高效非均匀数字信道化及信号重建技术;王芳;《电讯技术》;20110531;第51卷(第5期);第36-40页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113447893A (en) | 2021-09-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113447893B (en) | Radar pulse signal frequency spectrum automatic detection method, system and medium | |
| US10270626B2 (en) | Adaptive narrowband interference cancellation method, and apparatus | |
| CN102404271B (en) | Device and method for narrowband interference suppression of OFDM (orthogonal frequency division multiplexing) receiver | |
| WO2015172622A1 (en) | Method for radio-frequency interference suppression of high-frequency ground wave radar | |
| CN107911329B (en) | OFDM signal demodulation method of signal analyzer | |
| CN102263601B (en) | Multi-signal detecting method for broadband | |
| CN108811044B (en) | Frequency scanning method and device for small-bandwidth communication system | |
| CN114025379B (en) | Broadband multi-signal detection method, device and equipment | |
| CN102904604A (en) | Narrow-band interference suppression method and device | |
| CN111510255B (en) | Frequency hopping signal blind detection and parameter estimation method based on broadband frequency spectrum data | |
| CN106656372B (en) | Frequency band interference detection method of frequency hopping system | |
| CN108900445B (en) | Method and device for estimating signal symbol rate | |
| CN108847910B (en) | Spectrum sensing method and device and spectrum sensing equipment | |
| CN108063641B (en) | Single-channel multi-signal detection method | |
| CN101895370B (en) | Method for detecting interference of OFDM communication system | |
| CN110286392B (en) | Frequency domain narrow-band interference resistance realization method based on down-sampling | |
| CN102264120B (en) | Terminal and method for searching cell frequency point | |
| CN115801142A (en) | Multi-bandwidth mode wireless signal detection method based on dual-mode communication standard | |
| CN113965215B (en) | Method for single pulse tracking demodulation by using high-speed frequency hopping signal | |
| CN108737319A (en) | A kind of real-time detection method and device of target ofdm signal | |
| JP5252430B2 (en) | Signal detection method, program, information storage medium, and sensor | |
| CN114553656A (en) | Weak signal capturing method based on unequal-length double-block zero-filling algorithm | |
| CN114584444A (en) | Multi-h CPM modulation index estimation method based on cyclic moment characteristics | |
| CN109245839B (en) | Method for detecting narrow-band interference, communication chip and communication device thereof | |
| Jadhav et al. | A novel approach to wavelet transform-based edge detection in wideband spectrum sensing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |