CN118091651A - Multi-target regional rapid through-wall imaging method under polar coordinate system - Google Patents
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Abstract
The invention relates to a multi-target regional rapid through-wall imaging method under a polar coordinate system, which belongs to the technical field of through-wall radar imaging and comprises the following steps: preprocessing a target echo signal to remove wall echo and background clutter; carrying out one-dimensional constant false alarm detection on the central channel, and extracting the number of targets and the electric length corresponding to the positions of the targets; step 2, measuring that the electric length of the target position is larger than the real distance of the target due to the existence of the wall, and obtaining the relation between the real distance of the target and the electric length according to detailed mathematical deduction; calculating the difference between the electric length corresponding to the target position and the real distance and the width of the main echo lobe, and determining the width of the local imaging strip; the true distance at which each target is located is striped. The method shortens the time consumption of the algorithm, avoids the condition that strong targets mask weak targets due to energy attenuation, and corrects the deviation of the imaging positions of the targets due to the existence of the wall body by deducing the wall body compensation formula under the polar coordinate system.
Description
Technical Field
The invention belongs to the technical field of through-wall radar imaging, and particularly relates to a multi-target regional rapid through-wall imaging method under a polar coordinate system.
Background
The ultra-wideband through-wall radar is used as an emerging technology for detecting objects blocked by obstacles, and has wide application prospects in the fields of earthquake relief and the like. For higher resolution, multiple-input multiple-output (MIMO) arrays are often used, and due to the large number of transmit-receive arrays, a lot of time is consumed in directly imaging the detection scene, and real-time detection is difficult to achieve. When a plurality of targets exist in a scene, due to the fact that the attenuation of radar energy along with the distance is large, the condition that a short-distance strong target covers a long-distance weak target can occur, and detection is caused to generate false alarm. In addition, since the wall body changes the propagation path of electromagnetic waves, there is a gap between the target position detected by the radar and the actual target position, and thus compensation for the wall body is also an important content of research.
Disclosure of Invention
In order to solve the technical problems of low imaging speed of a large scene, masking of a weak target by a strong target, target imaging position deviation caused by existence of a wall body and the like, the invention provides a multi-target regional rapid through-wall imaging method under a polar coordinate system, which converts imaging under a traditional rectangular coordinate system into imaging under the polar coordinate system, and utilizes a single channel to search for a region where a locking target possibly appears to locally image the region. And correcting the offset of the target imaging position caused by the existence of the wall body by deducing a wall body compensation formula under the polar coordinate system.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a multi-target regional rapid through-wall imaging method under a polar coordinate system comprises the following steps:
step 1, preprocessing a target echo signal, and removing wall echo and background clutter;
Step 2, carrying out one-dimensional constant false alarm detection on the central channel, and extracting the number of targets and the electric length corresponding to the positions of the targets;
Step 3, deducing the relation between the real distance of the target and the electric length corresponding to the position of the target in the step 2;
Step 4, calculating the difference between the electric length corresponding to the position of the target in the step 2 and the real distance of the target and the width of the main echo lobe, and determining the width of the local imaging strip;
And 5, carrying out banded imaging on the real distance of each target.
The beneficial effects are that:
The method is used for ultra-wideband MIMO through-wall target imaging, can accurately and efficiently display the real position of the target, and avoids the problem that a strong target covers a weak target due to energy transmission. The specific expression is as follows:
(1) After the strips where the targets are located are confirmed, the strips are imaged independently, so that mutual interference among different strip targets is avoided, and the phenomenon that strong targets cover weak targets due to energy attenuation is avoided.
(2) Compared with global direct imaging, the local imaging of each strip has smaller calculation amount, so that the calculation efficiency is greatly improved, and the imaging implementation requirement is met.
(3) In the case of through-wall, the target imaging position shift due to the existence of the wall is corrected.
Drawings
FIG. 1 is a flow chart of a multi-target split area fast through-wall imaging method in a polar coordinate system according to an embodiment of the present invention;
fig. 2 is a diagram of the positions of transmit, receive and equivalent elements of a MIMO array;
FIG. 3 is a schematic diagram of one-dimensional CFAR detection of center channel echo data;
Fig. 4 (a), fig. 4 (b) is a geometric schematic; wherein, fig. 4 (a) is a geometric schematic diagram of the target on the right side of the array, and fig. 4 (b) is a geometric schematic diagram of the target on the left side of the array;
FIG. 5 is a schematic view of a display With target angle/>Is a variation of the schematic diagram;
FIG. 6 is a schematic diagram of mesh subdivision in strips;
FIG. 7 (a), FIG. 7 (b) is a graph of imaging results of two algorithms; fig. 7 (a) is an imaging result diagram of a conventional back projection algorithm, and fig. 7 (b) is an imaging result diagram of the proposed algorithm.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
As shown in fig. 1, the multi-target regional fast through-wall imaging method in the polar coordinate system of the invention comprises the following steps:
Step 1: preprocessing a target echo signal to remove wall echo and background clutter;
The MIMO radar used has Multiple transmit antennas (i.e., transmit array elements) and/>A number of receiving antennas (i.e. receiving array elements), so that the number of signal channels can be equivalent to/>:
(1)
The method for removing the wall echo and the background clutter adopts a background subtraction method: record the target present timeThe echo signals are/>No target time/>Echo signal of channel is/>The/>, after removing the wall echo and the background clutterEcho signal of channel is/>:
(2)
Traversing all channels, and removing wall echo and background clutter of all channels.
Step 2: performing one-dimensional Constant False Alarm (CFAR) detection on the central channel, and extracting the number of targets and the electrical length corresponding to the positions of the targets;
The array has 2 transmitting array elements and 5 receiving array elements, the number of the corresponding equivalent array elements is 10, and the transmitting array elements, the receiving array elements and the equivalent array elements are drawn in the same picture, as shown in figure 2. The center of the array of the equivalent array elements is taken as the origin of coordinates, namely the position of the middle receiving antenna, the channel corresponding to the equivalent array element closest to the right side of the origin is selected as the center channel, and the one-dimensional CFAR detection process of the center channel is shown in fig. 3.
Sampling the echo signal of the central channel, wherein the sampling point number isThe sampled signal can therefore be written as: in FIG. 3/> The detected unit at the current moment is provided with reference sliding windows at the front side and the rear side of the detected unit, wherein the reference sliding windows are respectively a front sliding window and a rear sliding window, and the lengths of the two reference sliding windows are respectively/>Which is at a fixed distance/>, from the detected unit,/>The unit in (a) is a protection unit,/>Is the background power estimated from the signal in the two-sided reference sliding window. /(I)Is a normalized factor, the size of which is defined by the length/>, of the reference sliding windowPreset false alarm probability/>Etc. factors determine, pair/>The decision is made by the sampling points, and the decision rule is as follows:
(3)
taking the distance corresponding to the center of the interval with the value of 1 as the electric length corresponding to the position of the target 。
Step 3: deducing the relation between the real distance of the target and the electric length corresponding to the position of the target;
Because the central channel is very close to the origin of coordinates, the central channel can be approximately considered to be positioned on the origin, a polar coordinate system is established by taking the position as the center, the derivation is respectively carried out according to the target angle smaller than 90 DEG and larger than 90 DEG, and the geometric schematic diagrams are shown in fig. 4 (a) and 4 (b). The point a in fig. 4 (a) and 4 (b) is a central channel, that is, a coordinate origin, the pixel point P is a refractive point of the electromagnetic wave on the inner wall surface, the line segment AP and the line segment PT are paths of the electromagnetic wave propagating in the wall body and the air, respectively, the line segment AT and the inner wall surface intersect AT a point Q, Is the true distance of the target to the origin, two dashed lines/>And/>Is the normal line of the inner side wall surface of the pixel point P and the point Q respectively,/>And/>Incident angle and refraction angle, respectively,/>Is the corresponding refraction angle in the wall when the electromagnetic wave is incident along the TA direction,、/>And/>Is the included angle between the corresponding line segments in the figure, as shown in fig. 4 (a) and fig. 4 (b).
To obtain the actual path of electromagnetic wave, the extension line of the electromagnetic wave is drawn to the point B from the origin A of coordinates to PT, and the thickness and relative dielectric constant of the wall are respectivelyAnd/>. The actual path that the required electromagnetic wave is emitted to reach the target is/>Its corresponding electrical length/>The method comprises the following steps:
(4)
Wherein, Is a line segment/>Length of/(I)Is a line segment/>Is a length of (c).
Case one: the target is to the right of the array, as in the case of fig. 4 (a).
From the geometrical relationship it is possible to:
(5)
To be used in With target angle/>And incidence angle/>The following derivation is made:
(6)
the angle of refraction is known according to the Snell's theorem And incidence angle/>Relationship between:
(7)
substituting the formula (5), the formula (6) and the formula (7) into the formula (4) can obtain accurate electric length :
(8)
Approximate conditions were used: the method can obtain:
(9)
Substituting formula (9) into formula (8) can change the electrical length The simplification is as follows:
(10)
And a second case: the target is to the left of the array, the case shown in fig. 4 (b).
In this case the number of the elements to be formed is,The expression of (2) varies:
(11)
Substituting the formula (5), the formula (7) and the formula (11) into the formula (4) can obtain accurate electric length The method comprises the following steps:
(12)
in addition, the formula (9) needs to be adjusted as follows:
(13)
Substituting equation (12) into equation (9) reduces the electrical length to:
(14)
It can be seen that the electrical length expressions obtained under both conditions are the same, and are obtained by superimposing one term on the basis of the linear distance from the central array element, namely the origin of coordinates, to the target, and are recorded as ,/>Is an intermediate parameter.
Thus, for the electrical length corresponding to the position of the target obtained in step 2Need to remove/>The true distance from the target to the original point, namely the polar diameter/>, can be obtained:
(15)
Is equal to the target angle/>Related to, it follows the target angle/>The variation of (2) is shown in fig. 5. Get/>Mean value of (use/>)Representation) correct the initial distance of the target, at which time the corrected true distance of the target to the origin/>The method comprises the following steps:
(16)
Step 4: calculating the difference between the electric length corresponding to the position of the target and the real distance of the target and the width of the main echo lobe, and determining the width of the local imaging strip;
Calculating the resulting corrected true distance of the target to the origin by equation (16) As a center, a circular stripe is formed due to the target angle/>Cannot be determined by the central channel, so the true distance of the target to the origin, i.e. polar diameter/>The variation range of (2) is/>. To ensure that the target is contained in the strip, its width cannot be smaller thanThis is an initial limitation on the strip width.
In addition, to meet the imaging requirement, the main lobe of the single-channel echo signal needs to be included, and the distance corresponding to the width of the main lobe of the single-channel echo signal is recorded asThe stripe width cannot be smaller than/>。
From this, the range of the local imaging slices is determined: to be used forCentered, the width of the strip isAs shown in fig. 6, wherein the center dashed line is the center of the circular strip, the fork symbols represent the transmit antenna positions and the circular symbols represent the receive antenna positions. The outer wall surface is the interface of air and wall, and the transceiver antenna is placed in close proximity to the outer wall surface, and the inner wall surface is the interface of wall and air because of the thickness of the wall body. /(I)Is pixel/>The polar diameter of the position.
Step 5: the true distance at which each target is located is striped.
Performing grid subdivision in distance direction and angle direction on the strip divided in the step 4, namely, the subdivision direction is respectively along the polar diameter and the polar angle, the subdivision mode is uniform subdivision, and the sitting marks of all pixel points are marked. To calculate the distance between the pixel point and the antenna, the coordinates of the transmitting antenna and the receiving antenna are expressed as polar coordinates:
The transmitting antenna is denoted as The receiving antenna is denoted/>,/>And/>For the polar diameter and polar angle corresponding to the position of the transmitting antenna,/>And/>The polar diameter and the polar angle are corresponding to the positions of the receiving antennas.
Therefore, the linear distances between the pixel point and the transmitting antenna and the receiving antenna are respectively:
(17)
(18)
Wherein, Is pixel/>Linear distance to transmitting antennas,/>Is pixel/>Linear distance to the receiving antennas.
According to the electrical length calculated in step 3, the electrical length from the pixel point to each antenna through the wall can be expressed, i.e. the electrical length from the transmitting antenna to the pixel point in the case of passing through the wallAnd the electrical length from the pixel point to the receiving antennaThe method comprises the following steps of:
(19)
(20)
Wherein,
(21)
(22)
Wherein,For transmitting antenna and pixel/>Included angle between the connecting line of (C) and polar axis,/>For receiving antenna and pixel pointAn included angle between the connecting line of the (C) and the polar axis.
Thus, for transmit and receive antennas in the same channel, the pixel pointsCorresponding time delay/>The method comprises the following steps:
(23)
Where c is the speed of light in free space.
Phase compensation and superposition are carried out on the echoes of each channel to obtain a final imaging result:
(24)
Wherein,Is centered at/>Dirac function of >/>Is pixel/>Corresponding time delays.
Examples
In this embodiment, the feasibility of the present invention is simulated and analyzed by setting specific simulation parameters.
Four targets are set in the imaging region, and coordinates in a polar coordinate system are respectively as follows:
(1.5m,30°)、(2m,60°)、(2.5m,75°)、(3m,90°)
The coordinates in the corresponding rectangular coordinate system are respectively:
(1.299,0.75)、(0.647,2.4148)、(1,1.7321)、(0,3)
Other relevant simulation parameters set are shown in table 1 (example simulation parameter setting table):
TABLE 1
,
The imaging results of the conventional BP imaging algorithm and the proposed multi-target split-area rapid through-wall imaging method under the polar coordinate system are shown in FIG. 7 (a) and FIG. 7 (b) by simulating the obtained data by gprMax software (the software is an open-source electromagnetic simulation software). Therefore, the energy of the target in the imaging result of the traditional BP imaging algorithm is influenced by the position of the target, the condition that the strong target covers the weak target is very easy to generate, and the imaging position of the target and the real position of the target are offset due to the existence of a wall body. The multi-target regional rapid through-the-wall imaging method under the polar coordinate system can avoid the occurrence of the condition that a strong target covers a weak target while correcting the target position offset. In addition, in the imaging area shown in fig. 7 (a) and fig. 7 (b), the conventional BP imaging algorithm takes 0.052s, and the present invention takes 0.013s, so that the imaging efficiency is greatly improved.
Claims (6)
1. The multi-target regional rapid through-wall imaging method under the polar coordinate system is characterized by comprising the following steps of:
step 1, preprocessing a target echo signal, and removing wall echo and background clutter;
Step 2, carrying out one-dimensional constant false alarm detection on the central channel, and extracting the number of targets and the electric length corresponding to the positions of the targets;
Step 3, deducing the relation between the real distance of the target and the electric length corresponding to the position of the target in the step 2;
Step 4, calculating the difference between the electric length corresponding to the position of the target in the step 2 and the real distance of the target and the width of the main echo lobe, and determining the width of the local imaging strip;
And 5, carrying out stripe imaging on the true distance of each target.
2. The multi-target zonal fast through-the-wall imaging method according to claim 1, wherein step 1 comprises:
Using MIMO radar with The transmitting antennas form transmitting array elements,/>The number of signal channels is equivalent to/>A plurality of;
the method for removing the wall echo and the background clutter is background subtraction method, and specifically comprises the following steps: record the first time the object exists Channel echo signal is/>No. H/without targetEcho signal of channel is/>Utilization/>Subtracting/>Obtaining the/>, after removing the wall echo and the background clutterEcho signal of channel is/>; Traversing all channels, and removing wall echo and background clutter of all channels.
3. The multi-target zonal fast through-the-wall imaging method according to claim 2, wherein step 2 comprises:
Sampling the echo signals of the central channel, wherein the number of sampling points is that The sampled echo signal is recorded as: Pair/> The decision is made by the sampling points, and the decision rule is as follows:
(3)
Wherein, The detected unit at the current moment is shown, reference sliding windows exist on the front side and the rear side of the detected unit, and the lengths of the reference sliding windows are/>,/>Is the background power estimated from the signal in the reference sliding window on both sides,/>Is a normalized factor, the size of which is defined by the length/>, of the reference sliding windowPreset false alarm probability/>Determining;
obtaining the electric length corresponding to the position of the target 。
4. A multi-target zonal fast through-the-wall imaging method according to claim 3, wherein said step 3 comprises:
Electrical length The formula of (2) is:
(14)
Right part of the sign For/>,/>Is an intermediate parameter; /(I)Is the target angle;
For the electric length corresponding to the position of the target obtained in the step2 Remove/>Obtaining the real distance from the target to the original point, namely the polar diameter/>:
(15)
Taking outMean corrected target initial distance/>,/>Mean value of/>Indicating the electrical length/>, corresponding to the position of the target at the momentSubtracting/>For the corrected true distance/>, of the target to the origin。
5. The method for multi-target zonal fast through-wall imaging in polar coordinate system according to claim 4, wherein said step 4 comprises:
with corrected true distance of target to origin As a central annular band, the range of the local imaging band is: to/>Centered, the width of the annular strip is/>Is a circular region of/>Representation/>Maximum value of/(I)Representation/>Is a minimum of (2).
6. The method for multi-target zonal fast through-wall imaging in polar coordinate system according to claim 5, wherein said step 5 comprises:
establishing a polar coordinate system by taking the center of an antenna array as a coordinate origin and taking rays from the coordinate origin to the rightmost array element as polar axes, performing grid subdivision in the distance direction and the angle direction on the annular strip divided in the step 4, namely, the subdivision directions are respectively along the polar diameter and the polar angle, the subdivision mode is uniform subdivision, and marking the sitting mark of each pixel point as a target R represents the polar diameter,/>Representing a target angle; to calculate the distance between the pixel point and the antenna, the coordinates of the transmitting antenna and the receiving antenna are expressed as polar coordinates:
The transmitting antenna is denoted as The receiving antenna is denoted/>,/>And/>For the polar diameter and polar angle corresponding to the position of the transmitting antenna,/>And/>For receiving the polar diameter and polar angle corresponding to the position of the antenna, the pixel points/>Straight line distance to transmitting antenna/>And straight line distance to receiving antenna/>The method comprises the following steps:
(17)
(18)
According to the electrical length calculated in step 3 Pixel dot/>The electrical length from the transmitting antenna to each antenna is expressed by the electrical length/>, i.e. the electrical length from the transmitting antenna to the pixel pointAnd by pixel/>Electrical length to receive antennaThe method comprises the following steps of:
(19)
(20)
Wherein,
(21)
(22)
Wherein,For transmitting antenna and pixel/>Included angle between the connecting line of (C) and polar axis,/>For receiving antenna and pixel/>An included angle between the connecting line of the (E) and the polar axis;
for a transmitting antenna and a receiving antenna in the same channel, pixels Corresponding time delay/>For/>And/>Dividing the sum of (2) by the speed of light;
The echo signals of all channels are subjected to phase compensation and superposition to obtain a final imaging result :
(24)
Wherein,Is centered at the pixel/>Corresponding time delay/>Is set, t represents time.
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150198713A1 (en) * | 2014-01-13 | 2015-07-16 | Mitsubishi Electric Research Laboratories, Inc. | Method and System for Through-the-Wall Imaging using Compressive Sensing and MIMO Antenna Arrays |
US20170023673A1 (en) * | 2015-07-23 | 2017-01-26 | Mitsubishi Electric Research Laboratories, Inc. | Method and System for Through-the-Wall Radar Imaging |
CN108717188A (en) * | 2018-05-29 | 2018-10-30 | 成都理工大学 | Quick wall compensation method suitable for MIMO through-wall radar imagings |
CN113238221A (en) * | 2021-05-11 | 2021-08-10 | 沈阳航空航天大学 | MIMO through-wall radar imaging method based on two-dimensional minimum phase coherence factor |
CN117420550A (en) * | 2023-11-28 | 2024-01-19 | 中南大学 | Through-wall radar imaging method based on maximum echo energy selection back projection |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150198713A1 (en) * | 2014-01-13 | 2015-07-16 | Mitsubishi Electric Research Laboratories, Inc. | Method and System for Through-the-Wall Imaging using Compressive Sensing and MIMO Antenna Arrays |
US20170023673A1 (en) * | 2015-07-23 | 2017-01-26 | Mitsubishi Electric Research Laboratories, Inc. | Method and System for Through-the-Wall Radar Imaging |
CN108717188A (en) * | 2018-05-29 | 2018-10-30 | 成都理工大学 | Quick wall compensation method suitable for MIMO through-wall radar imagings |
CN113238221A (en) * | 2021-05-11 | 2021-08-10 | 沈阳航空航天大学 | MIMO through-wall radar imaging method based on two-dimensional minimum phase coherence factor |
CN117420550A (en) * | 2023-11-28 | 2024-01-19 | 中南大学 | Through-wall radar imaging method based on maximum echo energy selection back projection |
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