CN109490979B - Millimeter wave radiometer array structure suitable for near-field rapid imaging and design method - Google Patents
Millimeter wave radiometer array structure suitable for near-field rapid imaging and design method Download PDFInfo
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- CN109490979B CN109490979B CN201811339512.5A CN201811339512A CN109490979B CN 109490979 B CN109490979 B CN 109490979B CN 201811339512 A CN201811339512 A CN 201811339512A CN 109490979 B CN109490979 B CN 109490979B
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Abstract
A millimeter wave radiometer array structure suitable for near-field rapid imaging and a design method thereof comprise a plurality of identical one-dimensional phased arrays and supports of the one-dimensional phased arrays. Each one-dimensional phased array is composed of a plurality of multi-channel integrated receiver front-end modules with certain included angles. According to the near-field imaging principle of the radiometer, the required imaging range and spatial resolution index can be realized in the near-field region of the actual work of the millimeter wave radiometer by optimizing the channel interval of the front-end modules of the integrated receiver in the one-dimensional phased array, the included angle between the front-end modules and the overall size of the array, and the optimized side lobe level is obtained. The invention provides a millimeter wave radiometer array structure suitable for near-field rapid imaging aiming at radiometer near-field imaging application, and the millimeter wave radiometer array structure has lower side lobe level compared with a conventional plane array structure.
Description
Technical Field
The invention relates to a millimeter wave radiometer array structure suitable for near-field rapid imaging and a design method thereof, belonging to the technical field of microwave security remote sensing and millimeter wave imaging.
Background
The radiometer is a high-sensitivity device for receiving natural radiation or reflected electromagnetic waves of an object; the millimeter wave is an electromagnetic wave with the wavelength of millimeter magnitude (10 mm-1 mm) and the corresponding frequency of 30 GHz-300 GHz; millimeter wave radiometers refer to radiometers operating in the millimeter wave frequency range. The millimeter wave radiometer has the advantages of short wavelength, wide frequency band, certain penetrating power and no electromagnetic radiation, and is widely applied to military and civil application fields.
In recent years, as international anti-terrorism forms become more severe, security inspection for human bodies and their portable articles at entrances and exits of public places is becoming more urgent. The millimeter wave array radiometer has the rapid imaging capability, can detect and identify contraband articles carried by a human body in a non-contact manner, and is an effective means for realizing rapid human body security inspection.
The millimeter wave array radiometer is divided into two major categories, namely a focal plane system and a pupil plane system. The depth of field of the focal plane system millimeter wave array radiometer is limited, and the safety inspection imaging of automatic zooming and real-time tracking on a human body cannot be realized under the near field condition. The pupil plane system radiometer adopts a digital beam forming mode, can track human body motion in real time and perform near-field real-time imaging.
The antenna arrays of the conventional pupil plane system radiometer system are distributed in the same plane and are suitable for imaging a long-distance target; in near field imaging applications, such an array layout in the same plane may increase the side lobe level of the point spread function of the imaging system, and reduce the imaging quality of the system.
Disclosure of Invention
The technical problems solved by the invention are as follows: aiming at the problem that the side lobe level of the planar array layout of the millimeter wave radiometer array of the conventional pupil planar system is increased in near-field imaging, the millimeter wave radiometer array structure and the design method suitable for near-field rapid imaging are provided, the side lobe level is lower, and the performance of the millimeter wave radiometer in the near-field imaging application is improved.
The technical solution of the invention is as follows: the invention provides a millimeter wave radiometer array structure suitable for near-field rapid imaging, which comprises a plurality of identical one-dimensional phased arrays and one-dimensional phased array supports. The one-dimensional phased array is fixedly arranged in the phased array bracket. The one-dimensional phased array is composed of a plurality of integrated receiver front-end modules with certain included angles and used for receiving millimeter wave signals radiated by a target. The millimeter wave radiometer array structure can enable the millimeter wave radiometer to obtain a side lobe level lower than that of a conventional planar array when the millimeter wave radiometer is used for near-field imaging.
Furthermore, the front-end module of the integrated receiver in the one-dimensional phased array integrates an antenna and a radio frequency receiving channel, and may include 1 or a plurality of receiving channels. The interval between the front-end module channels of the integrated receiver is determined by the imaging range of the near-field imaging phased array in the scanning direction, and is usually 0.5-3 times of the working wavelength.
Furthermore, the one-dimensional phased array is composed of a plurality of integrated receiver front-end modules with certain included angles, and the included angle theta is about 2-7 degrees. The extended length of a one-dimensional phased array is determined by the required spatial resolution at a particular near-field imaging distance. In order to simplify the installation and the support design, the integrated front-end modules are symmetrically distributed relative to the central line of the array. And optimizing the included angle in front of the integrated front-end module by taking the lowest sidelobe level of the point spread function of the imaging system as a design criterion on a specific near-field imaging distance. The interval between the integrated front end modules should be as small as possible on the premise of meeting the installation requirement so as to obtain the main beam efficiency as high as possible.
Furthermore, in the direction perpendicular to the scanning direction of the phased array, the millimeter wave radiometer array comprises a plurality of identical one-dimensional phased arrays which are arranged at uniform intervals or non-uniform intervals, and the interval between the one-dimensional phased arrays is determined by the imaging range in the direction. The arrangement size of the one-dimensional phased array is determined by the spatial resolution at a specific imaging distance in the direction.
The millimeter wave radiometer array design method suitable for near field rapid imaging disclosed by the invention has the advantages that the near field imaging range requirement is realized by optimally designing the channel interval of the front end module of the integrated receiver in the one-dimensional phased array according to the near field imaging principle of the radiometer; the requirement of near-field imaging spatial resolution is met by optimally designing the overall size of the one-dimensional phased array; under the condition of ensuring the imaging spatial resolution, the included angle between front end modules in the one-dimensional phased array is optimally designed, the point spread function of a radiometer system is simulated, and the maximum side lobe level is enabled to be the lowest, so that the required array design is realized.
Compared with the prior art, the invention has the advantages that: according to the near-field imaging principle of a pupil plane system radiometer, according to the near-field imaging distance, the imaging range and the imaging resolution requirement, the channel interval of an integrated front-end module in a phased array, the size of the phased array, the arrangement interval between the phased arrays and the arrangement size of the phased array are determined through simulation of a system imaging point spread function; according to the design rule that the side lobe level of the phased array in the scanning direction is minimized in the near field specific imaging distance, the included angle between the integrated front end modules in the one-dimensional phased array is determined through simulation, and the array layout with a certain included angle is adopted according to the specific application requirement of the near field imaging, so that the side lobe level of the point spread function of the radiometer imaging system can be reduced compared with the conventional plane array layout, and the imaging performance of the millimeter wave radiometer system is improved.
Drawings
FIG. 1 is a millimeter wave radiometer array structure suitable for near field fast imaging according to the present invention, in which 1 is a one-dimensional phased array, 2 is the front end of an integrated receiver, and 3 is a phased array support;
FIG. 2 is a schematic diagram of a millimeter wave radiometer array and its near field imaging region;
FIG. 3 is an array layout and simulation result of an integrated receiver module in a phased array with an included angle of 0 degree, where (a) is an array layout diagram and (b) is an array point spread function simulation result;
FIG. 4 is an array layout and simulation result of an integrated receiver module in a phased array with an included angle of 1 degree, where (a) is an array layout diagram and (b) is an array point spread function simulation result;
FIG. 5 is a diagram of an array layout and simulation results when the included angle of the integrated receiver module in the phased array is 2 degrees, where (a) is a schematic diagram of the array layout, and (b) is a simulation result of an array point spread function;
FIG. 6 is an array layout and simulation result of an integrated receiver module in a phased array with an included angle of 3 degrees, where (a) is an array layout diagram and (b) is an array point spread function simulation result;
FIG. 7 is a diagram of an array layout and simulation results when an included angle of an integrated receiver module in a phased array is 5 degrees, where (a) is a schematic diagram of the array layout, and (b) is a simulation result of an array point spread function;
FIG. 8 is a diagram of an array layout and simulation results when the included angle of the integrated receiver module in the phased array is 7 degrees, where (a) is a schematic diagram of the array layout, and (b) is a simulation result of the point spread function of the array;
FIG. 9 is a diagram of an array layout and simulation results when the included angle of the integrated receiver module in the phased array is 10 degrees, where (a) is a schematic diagram of the array layout, and (b) is a simulation result of an array point spread function;
fig. 10 shows simulation results of an array when an included angle of an integrated receiver module in the phased array changes within a range of 0 to 10 degrees, (a) shows a spatial resolution simulation result, and (b) shows a maximum sidelobe level simulation result of an array point spread function.
Detailed Description
The structure and design method of millimeter wave radiometer array suitable for near field fast imaging proposed by the present invention are explained in detail below with reference to the accompanying drawings.
As shown in fig. 1, the present invention comprises: a plurality of same one-dimensional phased arrays 1 and one-dimensional phased array supports 3. Each one-dimensional phased array is formed by arranging a plurality of integrated receiver front ends 2 according to a certain included angle. The plurality of one-dimensional phased arrays are arranged at intervals into a two-dimensional array. The invention can obtain a side lobe level lower than that of the conventional planar arrangement array during near-field imaging.
The invention adopts the following technical ideas:
firstly, according to the working distance and the imaging area of the near field of the millimeter wave radiometer system, the imaging field range required by the radiometer system array is calculated. Then, according to the imaging space resolution requirement of the system at the working distance, and according to the basic theory of the antenna array, the approximate whole size of the antenna array is estimated. And secondly, estimating the channel interval of the integrated receiver module in the phased array according to the imaging field range requirement of the antenna array and the basic principle of phased array imaging. And thirdly, determining the size of the integrated receiver module according to the channel interval and the channel number of the integrated receiver module, and estimating the number of the integrated receiver modules required in the one-dimensional phased array according to the whole size of the antenna array. And finally, aiming at a near-field imaging area of the radiometer system, the included angle of the integrated receiver module is optimized, so that the side lobe level of the point spread function of the system is the lowest, and the final array arrangement is determined.
The following description will discuss a specific implementation of a millimeter wave radiometer array architecture suitable for near field fast imaging, with reference to a preferred embodiment.
First, as shown in fig. 2, a schematic view of the near field imaging area of a millimeter radiometer. The millimeter wave radiometer array is arranged at a distance D from the edge of the imaging area, and the imaged area is a rectangular area with a width W and a length L. The closer the imaging distance, the greater the field angle of the imaged object relative to the radiometer array, and the maximum imaging range required by the radiometer array according to the geometric relationship shown in FIG. 2
The maximum imaging range required by the radiometer array is Δ θ 0.927rad 53.13 ° (m) calculated as D1 m and W1 m
Then, the approximate overall size of the radiometer array is estimated based on the desired imaging spatial resolution requirements for the radiometer array. The spatial resolution of the radiometer system is estimated by the formula
Where H is the distance of the target from the radiometer system, λ is the operating frequency of the radiometer, DAThe overall size of the radiometer array. The spatial resolution of the radiometer system varies with the imaging distance, and is calculated, for example, as the spatial resolution required for the center B point of the near-field imaging region. Assuming the required spatial resolution of the B-spot is 5cm, the overall size of the array is
And secondly, estimating the channel interval of the integrated receiver module according to the requirement of the imaging field range. The imaging field range required according to this example is 0.927rad 53.13 ° and according to the phased array imaging principle, the imaging range of the phased array is related to the channel spacing by:
where θ is the phased array imaging range and d is the channel spacing in the phased array. From the imaging field range requirement of 53.13 degrees, the channel spacing of the integrated receiver module is calculated to be d equal to 1.25 λ.
And thirdly, determining the size of the integrated receiver module according to the channel interval and the channel number of the integrated receiver module. The number of channels of the integrated receiver module has an optimal value in engineering practice, and is generally in the range of 8-16. The number of channels of the integrated receiver module is too small, the number of modules required by the system is large, and the system integration level is too low; too many channels of an integrated receiver module, and the module workThe process is difficult to realize and the production and maintenance costs are high. Taking 8 channels as an example, the size of the integrated receiver module is about D M8 × 1.25 λ ≈ 10 λ. According to the overall size D of the antenna array A40 λ, and an integral receiver module size DMThe number of integrated receiver modules required in the one-dimensional phased array is estimated to be 4 at 10 λ.
And finally, aiming at a near-field imaging area of the radiometer system, the included angle of the integrated receiver module is optimized, so that the side lobe level of the point spread function of the system is the lowest, and the final array arrangement is determined. In the embodiment of the invention, the side lobe level of the point spread function at the center B of the optimized imaging area is taken as an example to perform the optimization calculation of the included angle. And according to the basic parameters and the geometric relationship of the array and the principle of phased array imaging, utilizing the Matlab to simulate the condition of a system point spread function of the array under the condition of different included angles, and comparing indexes such as the maximum side lobe level, the 3dB wave beam efficiency and the like. In simulation, the working frequency of a radiometer system is 34GHz, and the installation interval between 4 integrated receiver modules in a phased array is designed to be 2 times of the channel interval of the integrated modules. By simulating the side lobe level of the point spread function of the system and calculating the 3dB wave beam efficiency under the condition of different included angles, the optimal array included angle parameter can be obtained.
Fig. 3 is a simulation result of a system point spread function with an included angle of 0 degree of an integrated receiver module, wherein the level of a first side lobe is-14.2 dB, and the 3dB beam width is about 3.7 cm.
Fig. 4 is a simulation result of a system point spread function with an included angle of 1 degree of the integrated receiver module, wherein the level of a first minor lobe is-15.3 dB, and the beam width of 3dB is 3.7 cm.
Fig. 5 is a simulation result of a system point spread function with an included angle of 2 degrees of an integrated receiver module, wherein the level of a first side lobe is-16.7 dB, and the beam width of 3dB is 4.0 cm.
FIG. 6 shows the simulation result of the point spread function of the system with an included angle of 3 degrees for the integrated receiver module, where the first minor lobe level is-17.2 dB and the 3dB beam width is 4.0 cm.
Fig. 7 is a simulation result of a system point spread function with an included angle of 5 degrees of an integrated receiver module, wherein the level of a first minor lobe is-16.8 dB, and the beam width of 3dB is 4.3 cm.
Fig. 8 is a simulation result of a system point spread function with an included angle of 7 degrees of an integrated receiver module, in which a first minor lobe level is-15.8 dB and a 3dB beam width is 5.2 cm.
Fig. 9 is a simulation result of a system point spread function with an included angle of 10 degrees of an integrated receiver module, in which a first minor lobe level is-12.0 dB and a 3dB beam width is 8.6 cm.
Fig. 10 summarizes the relationship curves of the first minor lobe level, the 3dB beam width and the included angle under the conditions of different included angles, and it can be seen from this that, as the included angle of the integrated receiver module increases, the spatial resolution of the point spread function of the radiometer system gradually becomes worse, and when the included angle exceeds 7 degrees, the spatial resolution exceeds 5cm, and the system resolution requirement is not satisfied. The maximum sidelobe level of the system point spread function is firstly reduced and then gradually increased along with the increase of the included angle. When the included angle is about 3 degrees, the maximum side lobe level is the lowest and is-17.2 dB, and the resolution ratio is 4cm at the moment, so that the resolution ratio requirement is met. The sidelobe level is reduced by 3dB compared to a conventional planar array with an included angle of 0 degrees.
Although particular embodiments of the present invention have been described above, it will be appreciated by those skilled in the art that these are merely examples and that many variations or modifications may be made to these embodiments without departing from the principles and implementations of the invention, the scope of which is therefore defined by the appended claims.
Claims (4)
1. The utility model provides a millimeter wave radiometer array structure suitable for near field rapid imaging which characterized in that: the phased array system comprises a plurality of identical one-dimensional phased arrays and a phased array support, wherein the phased arrays are arranged in the phased array support, the phased arrays complete the near field scanning imaging function of the radiometer system, and the phased array support realizes the position mounting and fixing function of the phased arrays; the one-dimensional phased array comprises a plurality of same integrated receiver front-end modules, the receiver front-end modules are arranged at a certain included angle theta, and the receiver front-end modules are distributed in a bilateral symmetry mode relative to the center of the array.
2. The millimeter wave radiometer array structure suitable for near-field fast imaging, as claimed in claim 1, wherein: when imaging is carried out on the distance which is 5-6 times of the size of the array surface in front of the radiometer, the included angle theta ranges from 2 degrees to 7 degrees.
3. The millimeter wave radiometer array structure suitable for near-field fast imaging, as claimed in claim 2, wherein: the front-end module of the integrated receiver comprises 1 or more channels, and the interval between the channels is in a wavelength range of 0.5-3 times; the spacing between the front end modules of the integrated receiver is greater than the receiving channel spacing.
4. A millimeter wave radiometer array design method suitable for near-field rapid imaging is characterized by comprising the following steps: according to the near-field imaging principle of a radiometer, the requirement of the near-field imaging range is met by optimally designing the channel interval of the front-end module of the integrated receiver in the one-dimensional phased array; the requirement of near-field imaging spatial resolution is met by optimally designing the overall size of the one-dimensional phased array; under the condition of ensuring the imaging spatial resolution, the included angle between front end modules in the one-dimensional phased array is optimally designed, the point spread function of a radiometer system is simulated, and the maximum side lobe level is enabled to be the lowest, so that the required array design is realized.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101467303A (en) * | 2006-06-09 | 2009-06-24 | 秦内蒂克有限公司 | Phased array antenna system with two dimensional scanning |
| CN102288959A (en) * | 2011-06-20 | 2011-12-21 | 北京理工大学 | Passive imaging system and method for millimeter wave focal plane |
| CN102844673A (en) * | 2010-04-20 | 2012-12-26 | 国际商业机器公司 | Phased array millimeter wave imaging techniques |
| WO2017149094A1 (en) * | 2016-03-03 | 2017-09-08 | Qinetiq Limited | Detection device |
| CN108088570A (en) * | 2016-11-23 | 2018-05-29 | 北京遥感设备研究所 | A kind of radiometers image-forming method based on phase-array scanning system |
| CN108258406A (en) * | 2018-01-11 | 2018-07-06 | 淮阴师范学院 | A kind of millimeter of wave polarization detection radiometer |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9030354B2 (en) * | 2012-03-12 | 2015-05-12 | International Business Machines Corporation | Imaging architecture with code-division multiplexing for large aperture arrays |
-
2018
- 2018-11-12 CN CN201811339512.5A patent/CN109490979B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101467303A (en) * | 2006-06-09 | 2009-06-24 | 秦内蒂克有限公司 | Phased array antenna system with two dimensional scanning |
| CN102844673A (en) * | 2010-04-20 | 2012-12-26 | 国际商业机器公司 | Phased array millimeter wave imaging techniques |
| CN102288959A (en) * | 2011-06-20 | 2011-12-21 | 北京理工大学 | Passive imaging system and method for millimeter wave focal plane |
| WO2017149094A1 (en) * | 2016-03-03 | 2017-09-08 | Qinetiq Limited | Detection device |
| CN108088570A (en) * | 2016-11-23 | 2018-05-29 | 北京遥感设备研究所 | A kind of radiometers image-forming method based on phase-array scanning system |
| CN108258406A (en) * | 2018-01-11 | 2018-07-06 | 淮阴师范学院 | A kind of millimeter of wave polarization detection radiometer |
Non-Patent Citations (1)
| Title |
|---|
| 被动毫米波实时成像技术;苗俊刚 等;《微波学报》;20131031;第29卷(第5-6期);第110-112页 * |
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