CN105093209B - Suitable for the random pulse minimizing technology that sonar one-dimensional range profile invariant feature is extracted - Google Patents
Suitable for the random pulse minimizing technology that sonar one-dimensional range profile invariant feature is extracted Download PDFInfo
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- CN105093209B CN105093209B CN201510502805.0A CN201510502805A CN105093209B CN 105093209 B CN105093209 B CN 105093209B CN 201510502805 A CN201510502805 A CN 201510502805A CN 105093209 B CN105093209 B CN 105093209B
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- 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
- G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
- G01S7/52001—Auxiliary means for detecting or identifying sonar signals or the like, e.g. sonar jamming signals
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- 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
- G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
- G01S7/523—Details of pulse systems
- G01S7/526—Receivers
- G01S7/527—Extracting wanted echo signals
- G01S7/5273—Extracting wanted echo signals using digital techniques
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- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
The invention discloses a kind of random pulse minimizing technology extracted suitable for sonar one-dimensional range profile invariant feature, including：S101, sonar transmit cycle linear frequency modulation continuous wave signal, and reception of echoes signal；S102, Stretch treatment is carried out to the echo-signal, obtain frequency domain echo signal；S103, Threshold detection is carried out to the frequency domain ripple signal, filtered out the N of the first threshold value1Individual frequency；S104, repetition S103, filtered out the other N of the first threshold value2Individual frequency；S105, correspond to compare each element in W and U two-by-two, if the absolute value of the two difference is less than or equal to the second threshold value, and SiThe ratio of/ρ is more than the 3rd threshold value, then be judged as object echo, and its residual value is judged as random pulse.Random pulse is removed in the signal that the present invention can be received from sonar.
Description
Technical field
The present invention relates to sonar technical field, more particularly to a kind of extract suitable for sonar one-dimensional range profile invariant feature
Random pulse minimizing technology.
Background technology
Sonar system suffers from various Fuzz pulsing effects, and mixed and disorderly sound wave pulse is formed by force for sonar detection of echoes
Strong influence, makes it to complete object detection.This is, because conventional sonar is using technologies such as Adaptive beamformers, not to be suitable for
The treatment of mixed and disorderly ping.The arrival spatial domain of mainly such mixed and disorderly ping may be from different directions, cause self adaptation
Wave beam forming scheduling algorithm can not restrain.It is therefore desirable to develop new method, mixed and disorderly ping is removed.
The content of the invention
The technical problems to be solved by the invention are, for the frequency information dimension of sonar echo range information conversion,
A kind of random pulse minimizing technology, the random pulse in removal sonar are provided, so as to obtain a kind of pure time-frequency domain sonar return
Acoustical signal.
In order to solve the above-mentioned technical problem, extracted suitable for sonar one-dimensional range profile invariant feature the invention provides a kind of
Random pulse minimizing technology, including：
S101, sonar transmit cycle linear frequency modulation continuous wave signal, and reception of echoes signal, wherein, the echo signal
The echo pulse formed after being reflected through object including random pulse and the chirp pulse signal；
S102, Stretch treatment is carried out to the echo signal, obtain frequency domain echo signal；
S103, Threshold detection is carried out to the frequency domain echo signal, filtered out the N of the first threshold value1Individual frequency
S104, repetition S103, filtered out the other N of the first threshold value2Individual frequency
S105, correspond to compare each element in W and U two-by-two, if the absolute value of the two difference is less than or equal to the second threshold value,
And SiThe ratio of/ρ is more than the 3rd threshold value, then be judged as object echo, and its residual value is judged as mixed and disorderly ping；Wherein, SiRepresent
The average energy of each sampled point of the corresponding pulse of current frequency, ρ represents pulse corresponding less than the frequency of the first threshold value
Each sampling point value average value.
Further, the sonar transmit cycle linear frequency modulation continuous wave signal, and reception of echoes signal, specifically includes：
Sonar transmit cycle linear frequency modulation continuous wave signal, wherein, the chirp pulse signal isIn formula, t is time variable, fcIt is carrier frequency, ξ is chirp rate, and T is CW with frequency modulation
Cycle, rect [] represents a cycle of cycle square wave；
Sonar receives the echo signal of multiple objects, wherein, the multiple object echo signal isIn formula, αiIt is the amplitude complex coefficient of i-th echo pulse, τiIt is i-th echo pulse
Time delay, n (t) for sonar receiving channel noise, M for echo object number.
Further, Stretch treatment is carried out to the echo signal, obtains frequency domain echo signal, specifically included：
OrderIt is cycle continuous wave transforming function transformation function, the echo signal is carried out at Stretch
Reason, obtains signal z (t), i.e.,
0 in formula<t<NT, N represent all number of cycles of transmitting CW with frequency modulation；
Choosing one section therein of signal z (t) carries out Fourier transformation, obtains frequency domain echo signal, wherein, the frequency
Domain echo signal isα is integer or fraction, that is, the data length of the Fourier transformation chosen is
The integral multiple or fraction of cycle T times.
Further, Threshold detection is carried out to the frequency domain echo signal, filtered out the N of the first threshold value1Individual frequencySpecifically include：
Ask for the envelope of the frequency domain echo signalIn formula, yI(ω) and yQ(ω)
It is the real part and imaginary part of frequency domain echo signal y (ω)；
Filter out and meet A (ω)>The N of ω during σ1Individual value, as the N for crossing the first threshold value1Individual frequencyWherein, σ is the first threshold value.
The present invention is uncertain in frequency domain position using mixed and disorderly ping, and continuous at two through the echo signal of object reflection
The unconverted feature of frequency domain during ripple echo, by the judgement of thresholding position, determines object echo, so as to reach removal Fuzz
The purpose of pulse, the effect of the mixed and disorderly ping of present invention removal is good.
Brief description of the drawings
In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing
The accompanying drawing to be used needed for having technology description is briefly described, it should be apparent that, drawings in the following description are only this
Some embodiments of invention, for those of ordinary skill in the art, on the premise of not paying creative work, can be with
Other accompanying drawings are obtained according to these accompanying drawings.
Fig. 1 is the random pulse minimizing technology extracted suitable for sonar one-dimensional range profile invariant feature that the present invention is provided
The schematic flow sheet of one embodiment；
Fig. 2 is the transmission signal form of the Sonar Signal that the present invention is provided；
Fig. 3 is the signal form after Stretch treatment；
Fig. 4 is after the sonar random pulse minimizing technology provided through the present invention is processed, what first compares cycle was obtained
Object echo frequency domain characteristic figure.
Fig. 5 is after the sonar random pulse minimizing technology provided through the present invention is processed, what second compares cycle was obtained
Object echo frequency domain characteristic figure.
Specific embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete
Site preparation is described, it is clear that described embodiment is only a part of embodiment of the invention, rather than whole embodiments.It is based on
Embodiment in the present invention, it is every other that those of ordinary skill in the art are obtained under the premise of creative work is not made
Embodiment, belongs to the scope of protection of the invention.
Fig. 1 is the random pulse minimizing technology extracted suitable for sonar one-dimensional range profile invariant feature that the present invention is provided
The schematic flow sheet of one embodiment, as shown in figure 1, including：
S101, sonar transmit cycle linear frequency modulation continuous wave signal, and reception of echoes signal, wherein, the echo signal
The echo pulse formed after being reflected through object including random pulse and the chirp pulse signal.
Specifically, S101 includes step：
Sonar transmit cycle linear frequency modulation continuous wave signal, wherein, the chirp pulse signal isIn formula, t is time variable, fcIt is carrier frequency, ξ is chirp rate, and T is CW with frequency modulation
Cycle, rect [] represents a cycle of cycle square wave；
Sonar receives the echo signal of multiple objects, wherein, the multiple object echo signal isIn formula, αiIt is the amplitude complex coefficient of i-th echo pulse, τiIt is i-th echo pulse
Time delay, n (t) for sonar receiving channel noise, M for echo object number.
S102, Stretch treatment is carried out to the echo signal, obtain frequency domain echo signal.
Specifically, S102 includes step：
OrderIt is cycle continuous wave transforming function transformation function, the echo signal is carried out at Stretch
Reason, obtains signal z (t), i.e.,
0 in formula<t<NT, N represent all number of cycles of transmitting CW with frequency modulation；
Choosing one section therein of signal z (t) carries out Fourier transformation, obtains frequency domain echo signal, wherein, the frequency
Domain echo signal isα is integer or fraction, that is, the data length of the Fourier transformation chosen is
The integral multiple or fraction of cycle T times.
S103, Threshold detection is carried out to the frequency domain echo signal, filtered out the N of the first threshold value1Individual frequency
Specifically, S103 includes step：
Threshold detection is carried out to the frequency domain echo signal, the N of the first threshold value was filtered out1Individual frequencySpecifically include：
Ask for the envelope of the frequency domain echo signalIn formula, yI(ω) and yQ(ω)
It is the real part and imaginary part of frequency domain echo signal y (ω)；
Filter out and meet A (ω)>The N of ω during σ1Individual value, as the N for crossing the first threshold value1Individual frequencyWherein, σ is the first threshold value.
S104, repetition S103, filtered out the other N of the first threshold value2Individual frequency
S105, correspond to compare each element in W and U two-by-two, if the absolute value of the two difference is less than or equal to the second threshold value,
And SiThe ratio of/ρ is more than the 3rd threshold value, then be judged as object echo, and its residual value is judged as mixed and disorderly ping；Wherein, SiRepresent
The average energy of each sampled point of the corresponding pulse of current frequency, ρ represents pulse corresponding less than the frequency of the first threshold value
Each sampling point value average value.
Simulating, verifying is carried out below for the embodiment of the present invention, verification condition does following setting：Interference-to-noise ratio 20dB；Letter
Number noise is than 20dB (Stretch before processings)；The linear frequency modulation continuous wave signal period 30ms, signal bandwidth 5kHz of transmitting.Hair
Penetrate 30 CW with frequency modulation signals in cycle.Object is shown in Table 1 with the coal addition position of random pulse in emulation.Take the first threshold value σ
Level value is 40, and the second threshold delta is 5, and the 3rd threshold value μ is 6.Emulation frequency domain pulse 2 is returning after being reflected through target
Ripple signal, i.e. echo signal, remaining is random pulse.Two segment signals analysis frequency domain characteristic is taken, the data of Fourier transformation are carried out
Length is taken as 1.5 times of continuous period of wave, i.e. 45ms.Two Analysis Blocks take adjacent data.
Fig. 4 and Fig. 5 sets forth the object echoing characteristic obtained after present invention method treatment.Each echo is frequently
Spectrum SiThe value of/ρ is all higher than 6.From Fig. 4 and Fig. 5, during the echo reception in two contrast cycles, object is on frequency domain
It is closer to.And remaining random pulse occurs in the cycle of echo processing twice without correspondence.Observation table 2 obtains frequency domain peak
Value position, by comparing the peak of threshold signal, determines that site error absolute value is object less than threshold value, remaining
Threshold impulse is crossed for mixed and disorderly ping.Hence it is demonstrated that correctness of the invention.
The random pulse that the emulation of table 1 is added is with object in the position of range gate
| Sequence number | Selected data section 1 | Selected data section 2 | |
| 1 | 1 | Random pulse | |
| 2 | 30 | 39 | Random pulse |
| 3 | 70 | 70 | Object |
| 4 | 110 | 110 | Object |
| 5 | 150 | 150 | Object |
| 6 | 190 | 190 | Object |
| 210 | Random pulse |
Table 2 takes the signal frequency of two segment datas acquisition
The present invention uses periodic linear CW with frequency modulation signal, uncertain in frequency domain peak value using mixed and disorderly ping, and passes through
Object reflection echo impulse during two compares cycles frequency domain change it is small the characteristics of, by the judgement of thresholding position, it is determined that
Echo object, so as to reach the purpose of removal random pulse, the effect of present invention removal random pulse is good.
It should be noted that herein, term " including ", "comprising" or its any other variant be intended to non-row
His property is included, so that process, method, article or device including a series of key elements not only include those key elements, and
And also include other key elements being not expressly set out, or also include for this process, method, article or device institute are intrinsic
Key element.In the absence of more restrictions, the key element limited by sentence "including a ...", it is not excluded that including this
Also there is other identical element in the process of key element, method, article or device.
Professional further appreciates that, with reference to the unit of each example of the embodiments described herein description
And algorithm steps, can be realized with electronic hardware, computer software or the combination of the two, in order to clearly demonstrate hardware and
The interchangeability of software, generally describes the composition and step of each example according to function in the above description.These
Function is performed with hardware or software mode actually, depending on the application-specific and design constraint of technical scheme.Specialty
Technical staff can realize described function to each specific application using distinct methods, but this realization should not
Think beyond the scope of this invention.
The step of method or algorithm for being described with reference to the embodiments described herein, directly can be held with hardware, processor
Capable software module, or the two combination is implemented.Software module can be placed in random access memory (RAM), internal memory, read-only deposit
Reservoir (ROM), electrically programmable ROM, electrically erasable ROM, register, hard disk, moveable magnetic disc, CD-ROM or technology
In field in known any other form of storage medium.
The foregoing description of the disclosed embodiments, enables professional and technical personnel in the field to realize or uses the present invention.
Various modifications to these embodiments will be apparent for those skilled in the art, as defined herein
General Principle can be realized in other embodiments without departing from the spirit or scope of the present invention.Therefore, the present invention
The embodiments shown herein is not intended to be limited to, and is to fit to and principles disclosed herein and features of novelty phase one
The scope most wide for causing.
Claims (4)
1. it is a kind of suitable for sonar one-dimensional range profile invariant feature extract random pulse minimizing technology, it is characterised in that including：
S101, sonar transmit cycle linear frequency modulation continuous wave signal, and reception of echoes signal, wherein, the echo signal includes
The echo that random pulse and the linear frequency modulation continuous wave signal are formed after being reflected through object；
S102, Stretch treatment is carried out to the echo signal, obtain frequency domain echo signal；
S103, Threshold detection is carried out to the frequency domain echo signal, filtered out the N of the first threshold value1Individual frequency
S104, repetition S103, filtered out the other N of the first threshold value2Individual frequency
S105, correspond to compare each element in W and U two-by-two, if the absolute value of the two difference is less than or equal to the second threshold value, and Si/
The ratio of ρ is more than the 3rd threshold value, then be judged as object echo, and its residual value is judged as mixed and disorderly ping；Wherein, SiRepresent current
The average energy of each sampled point of the corresponding pulse of frequency, ρ represents each of pulse corresponding less than the frequency of the first threshold value
The average value of sampling point value.
2. it is as claimed in claim 1 to be applied to the random pulse minimizing technology that sonar one-dimensional range profile invariant feature is extracted, its
It is characterised by, the sonar transmit cycle linear frequency modulation continuous wave signal, and reception of echoes signal, specifically include：
Sonar transmit cycle linear frequency modulation continuous wave signal, wherein, the linear frequency modulation continuous wave signal isIn formula, t is time variable, fcIt is carrier frequency, ξ is chirp rate, and T is CW with frequency modulation week
Phase, rect [] represents a cycle of cycle square wave；
Sonar receives the echo signal of multiple objects, wherein, the multiple object echo signal is
In formula, αiIt is i-th amplitude complex coefficient of echo, τiIt is i-th time delay of echo, n (t) is the receiving channel noise of sonar, M
It is the number of echo object.
3. it is as claimed in claim 2 to be applied to the random pulse minimizing technology that sonar one-dimensional range profile invariant feature is extracted, its
It is characterised by, Stretch treatment is carried out to the echo signal, obtain frequency domain echo signal, specifically includes：
OrderIt is cycle continuous wave transforming function transformation function, Stretch treatment is carried out to the echo signal, obtains
To signal z (t), i.e.,
0 ＜ t ＜ NT, N represents all number of cycles of transmitting CW with frequency modulation in formula；
Choosing one section therein of signal z (t) carries out Fourier transformation, obtains frequency domain echo signal, wherein, the frequency domain is returned
Acoustical signal isα is integer or fraction, that is, the data length of the Fourier transformation chosen is cycle T
Integral multiple or fraction times.
4. it is as claimed in claim 3 to be applied to the random pulse minimizing technology that sonar one-dimensional range profile invariant feature is extracted, its
It is characterised by, Threshold detection is carried out to the frequency domain echo signal, filtered out the N of the first threshold value1Individual frequencySpecifically include：
Ask for the envelope of the frequency domain echo signalIn formula, yI(ω) and yQ(ω) is frequency domain
The real part and imaginary part of echo-signal y (ω)；
Filter out the N of ω when meeting A (ω) ＞ σ1Individual value, as the N for crossing the first threshold value1Individual frequencyWherein, σ is the first threshold value.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102176008A (en) * | 2010-12-22 | 2011-09-07 | 中国船舶重工集团公司第七一五研究所 | Phased azimuth filtering method for three-dimensional stratum imaging |
| CN104019803A (en) * | 2014-05-16 | 2014-09-03 | 东华理工大学 | Water area, mud flat and bank slope geospatial information measuring platform based on double-ship mode |
| CN104569991A (en) * | 2015-02-06 | 2015-04-29 | 中国安全生产科学研究院 | Sonar detection device for three-dimensional space of mine gob |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US8747321B2 (en) * | 2012-08-15 | 2014-06-10 | Scidea Research, Inc. | Structured random permutation pulse compression systems and methods |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102176008A (en) * | 2010-12-22 | 2011-09-07 | 中国船舶重工集团公司第七一五研究所 | Phased azimuth filtering method for three-dimensional stratum imaging |
| CN104019803A (en) * | 2014-05-16 | 2014-09-03 | 东华理工大学 | Water area, mud flat and bank slope geospatial information measuring platform based on double-ship mode |
| CN104569991A (en) * | 2015-02-06 | 2015-04-29 | 中国安全生产科学研究院 | Sonar detection device for three-dimensional space of mine gob |
Non-Patent Citations (1)
| Title |
|---|
| "Stretch processing for masking effect removal in noise radar";J. Misiurewicz etc.;《IET Radar Sonar Navig.》;20081231;第2卷(第4期);274-283 * |
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