CN101931124A - Embattling method of logarithmic spiral array antennas - Google Patents
Embattling method of logarithmic spiral array antennas Download PDFInfo
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- CN101931124A CN101931124A CN2009102633900A CN200910263390A CN101931124A CN 101931124 A CN101931124 A CN 101931124A CN 2009102633900 A CN2009102633900 A CN 2009102633900A CN 200910263390 A CN200910263390 A CN 200910263390A CN 101931124 A CN101931124 A CN 101931124A
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Abstract
The invention discloses an embattling method of logarithmic spiral array antennas. An antenna array uses N logarithmic spirals to embattle; a single logarithmic spiral line function is as follows: r=e<a phi>, and an antenna unit is displaced on the logarithmic spiral line function r=e<a phi>, wherein (r, phi) is a position coordinate of any point on the logarithmic spiral line under polar coordinates, r is a distance from the point to an original point (unit: wavelength), namely a relative wavelength number, phi is an angle relative to a polar axis (0 degree), and a is a parameter of the logarithmic spiral line function and is an optimizable constant for designing the array; the antenna unit n on each logarithmic spiral is arranged at the position of phi n along the spiral line function; the phase difference between adjacent units is delta phi; N spiral lines rotate 360 degrees/N rounding a rotating shaft in turn; r of the initial starting point of each logarithmic spiral line is the same; the phase position of the initial starting point of the first starting point on each spiral line is phi0; m array elements are respectively arranged on each spiral line from the initial starting point at an interval of delta phi; one array element can be placed at the center of the array, namely original point, or not; when the parameter a, delta phi and phi0 are determined, an array manifold is determined; and the total antenna unit number of N logarithmic spiral arrays is Nm+1.
Description
Technical field
The present invention relates to super-resolution spatial spectrum (direction of arrival (Direction of Arrival, DOA)) estimation technique, relate in particular to a kind of logarithm helical array antenna method of structuring the formation, this method can realize (DOA) estimation of high-resolution 2-d direction finding and target measurement, imaging, can be applicable to fields such as radar system, communication system and astronomical observation.
Background technology
Super-resolution Estimation of Spatial Spectrum technology is called direction of arrival (Direction of Arrival again, DOA) estimation technique, the accurately direction of estimation space signal source and spatial distribution, break through the restriction of traditional direction finding system Rayleigh limit, have a wide range of applications in fields such as radio communication, radar, sonar, navigation, seismic survey and medical science.Obtaining of spatial spectrum be the superposition by antenna array signals and extract and realize, therefore, array manifold is that the width of cloth of geometry, the array element of array distributes mutually, the coupling between array element and the influence etc. of scattering object on every side are most important to Estimation of Spatial Spectrum.The analysis and synthesis method of antenna mainly still concentrates on the electromagnetic radiation characteristic aspect of antenna, the influence that less concern is obtained spatial spectrum at present; And in the Array Signal Processing Study on Theory, though the array manifold problem of one dimensional linear array there is more deep research, as waiting matrix, methods such as matrix, virtual array such as non-, to tallying with the actual situation more and two-dimensional array research is less more targetedly.The method that conventional employing increases antenna element spacing raising array resolution inevitably forms graing lobe, causes resolution to descend thereby false spectrum peak occurs.
Summary of the invention
For overcoming the defective of prior art, the present invention proposes a kind of logarithm helical array antenna method of structuring the formation, two-dimensional antenna array manifold-logarithm spiral battle array by a kind of novelty breaks through the restriction of conventional direction finding system Rayleigh limit, realizes high-resolution two-dimentional DOA estimation, goal orientation and imaging.
For achieving the above object, the present invention by the following technical solutions: a kind of logarithm helical array antenna method of structuring the formation is characterized in that: antenna array adopts N bar logarithm spiral to structure the formation, (N=2,3,4...), wall scroll log spiral equation is
Antenna element is in logarithm spiral equation
On,
Be on the log spiral arbitrarily some position coordinates under polar coordinates, r for point to the distance of the origin of coordinates (unit: wavelength) be the relative wavelength number,
Be angle with respect to pole axis (0 °), a is the parameter of log spiral equation, can be optimized according to the needs of technical indicators such as the beamwidth of antenna pattern, minor level during array design, the antenna element n on every logarithm spiral is positioned at along the helix equation
The place, phase difference is between adjacent cells
N bar helix rotates 360 °/N around rotating shaft successively, and the r of each bar log spiral initial starting point is identical, and the phase place of first antenna element initial starting point is on every helix
Be separated by from initial starting point on every helix
Each places m array element respectively, and array center is an initial point place placement array element (also can not putting), when parameter a,
When determining, array manifold is just definite fully, and the total antenna element number of N bar logarithm helical array is Nm+1 (array center is that the initial point place is Nm when not placing array element).
Described logarithm spiral battle array can be (being phase array) of sweeping mutually, also can right and wrong sweeps mutually;
Antenna element can be placed by the place, also can place the antenna submatrix.
In order to obtain best array layout, avoid occurring false spectrum peak, adopt the configuration of optimization method to antenna element, promptly adopt and comprise genetic algorithm (Genetic Algorithm, GA), ant group algorithm (Ant Colony Optimization, ACO), particle swarm optimization algorithm (Particle Swarm Optimization, PSO) at interior various algorithms, to influence parameter a that antenna pattern changes,
Be optimized.
Advantage of the present invention and remarkable result:
1) antenna array adopts many (2,3,4...) logarithm spirals to structure the formation, and has increased the antenna element spacing, has obtained big antenna aperature, sharpening antenna beam, improved the resolution of entire antenna.
2) owing to adopt logarithm spiral battle array, at x, the y flat unit is arranged and is presented characteristic aperiodic, thereby, eliminated the condition that graing lobe produces, broken through the Ruili limit of half-wavelength, on the basis that false spectrum peak do not occur, improved the resolution of antenna,, can obtain two-dimentional super-resolution signal and estimate in conjunction with modern array signal process technique.
3) antenna beamwidth is narrow, the antenna element number is few.Narrow directed radiation and the receiving ability that has improved antenna of antenna beamwidth, improved the angle resoluting ability of antenna, and compare with other forms of array (as linear array, circle battle array, two dimensional surface battle array), its antenna element digital display work descends, so just significantly reduce equipment amount, reduced construction and maintenance cost.
4) log spiral antenna formation formula, its antenna element spacing be much larger than half-wavelength (Ruili limit), but really can eliminate graing lobe in the antenna pattern through optimizing to structure the formation.The graing lobe of antenna (amplitude is near the secondary lobe of main lobe level) is to produce false spectrum peak, causes the basic reason of goal orientation and image blur.
5) the log spiral antenna battle array can combine with modern array signal process technique easily, produces high-resolution power spectrum, realizes the accurate location and the imaging of target.Strengthen the antenna element spacing, when increasing the antenna synthesis aperture, eliminating the graing lobe of aerial array again, breaking through the restriction of traditional direction finding system Rayleigh limit, improving the resolution of antenna array.This log spiral antenna battle array that shows simulation result realizes two-dimentional DOA estimation approach accurate and effective, and it can be applied to fields such as the many antenna mobile communication systems of MIMO (multiple input multiple output), MIMO radar system and radio astronomy research.
Description of drawings
Fig. 1 is a logarithm helical array schematic diagram of the present invention;
Fig. 2 is a helical array 2-d direction finding schematic diagram;
Fig. 3 is the helical array antenna directional diagram;
Fig. 4 is a helical array two-dimensional space spectrum drawing for estimate;
Fig. 5 is the adjacent incoming wave two-dimensional space spectrum of a helical array drawing for estimate;
Fig. 6 is that helical array two-dimensional space spectrum is estimated (SNR=0dB) figure.
Embodiment
The invention will be further described below in conjunction with drawings and the specific embodiments
Antenna array has a variety of forms according to the arranging situation of antenna element, and as linear array, circle battle array, two dimensional surface battle array etc., the present invention proposes a kind of logarithm helical array and realizes that by it the two-dimentional DOA of signal estimates.With three helical array is example (as shown in Figure 1), among the figure, and A1, A2 ... A10 is the residing position of antenna element on the same plane, and except that the A1 of initial point place, each point satisfies following equation:
Wherein r is the distance (relative wavelength number) that any point arrives the origin of coordinates on the helix,
Be angle with respect to pole axis (0 °),
Be on the log spiral arbitrarily some position coordinates under polar coordinates, a is the parameter of log spiral equation, can be optimized according to the needs of technical indicators such as the beamwidth of antenna pattern, minor level during array design.N bar helix rotates 360 °/N around rotating shaft successively, and three helixes rotate the control constant of 120 ° of selections successively around rotating shaft, and the antenna element n on every helix is positioned at along the helix equation
The place, phase difference is between adjacent cells
The r of each bar helix initial starting point is identical, and the phase place of first antenna element initial starting point is on the helix
Be separated by from initial starting point on every helix
Each places m array element respectively, array element of array center's placement, when parameter a,
When determining, array manifold is just definite fully.Article three, the total antenna element number of helical array is 3m+1.Because snail array element number is few relatively, unit interval is pressed index and is launched greater than half-wavelength, makes antenna aperature increase, and resolving power improves.Again because the randomness of unit cell arrangement has been destroyed the periodicity that graing lobe occurs, so can suppress graing lobe through optimizing array manifold.With respect to linear array, logarithm spiral battle array can provide pitching, orientation two-dimensional signal; With respect to circle battle array, logarithm spiral battle array can provide the resolution of lower minor level and Geng Gao.
In order to obtain best array layout, avoid occurring false spectrum peak, can adopt the configuration of optimization method to antenna element, Fig. 2,3 adopts optimized Algorithm, as genetic algorithm (Genetic Algorithm, GA), ant group algorithm (Ant ColonyOptimization, ACO), particle swarm optimization algorithm (Particle Swarm Optimization, PSO) to the location parameter of logarithm helicoid array antenna unit carry out complex optimum influence parameter a that antenna pattern changes,
As optimizing variable, the target of optimization is at poincare half plane, and antenna pattern is except that the main lobe district, and all secondary lobes all are lower than-12dB, through PSO optimize obtain 10 unit logarithm spiral battle arrays (Log spiral Array, parameters optimization LSA): a=0.1783,
The antenna pattern that calculates 10 unit LSA battle arrays as shown in Figure 3, antenna beamwidth θ
3dB=12.8 °, minor level SLL in the visual range＜-12dB.
Below be the antenna pattern simulation result of logarithm spiral array antenna:
Fig. 4,5 adopts Array Signal Processing MUSIC methods to obtain the two-dimensional space spectrum of normalization, all θs corresponding with " spectrum peak " with
Promptly provide the estimation of direction of arrival.When direction of arrival is θ
1=30 °, φ
1=250 °, θ
2=35 °, φ
2=120 °, fast umber of beats is 512, and when signal to noise ratio was 10dB, the simulation result that the logarithm helical array two-dimensional space of relevant parameter spectrum is estimated was seen Fig. 4.Signal spectra is higher than about noise signal 27dB.More approaching when two signal sources, direction of arrival is θ
1=30 °, φ
1=145 °; θ
2=35 °, φ
2=130 °, fast umber of beats is 512, and when signal to noise ratio was 10dB, the logarithm helical array two-dimensional space of relevant parameter spectrum estimation simulation result was seen Fig. 5.
Fig. 6 when promptly signal is submerged in the noise centre fully, still can obtain two-dimensional space spectrum clearly when signal to noise ratio is 0dB.In the example below, choosing fast umber of beats is 256, and direction of arrival is θ
1=30 °, φ
1=145 °; θ
2=35 °, φ
2=130 °, the two-dimensional space spectrum of acquisition as shown in Figure 6.As seen from the figure, signal spectrum peak still is higher than about noise signal 10dB.
The operation principle and the course of work of logarithm spiral battle array of the present invention:
If array number is N, the vectorial mould value that N＞P wherein, (P is the quantity of incoming wave, i.e. number of targets) initial point point to each array element be r (n) (n=1,2 ..., N), the azimuth is
The rectangular coordinate of each array element is A
n(x
n, y
n), then
If the direction of arrival angle of pitch is θ
1, θ
2..., θ
P, the azimuth is φ
1, φ
2... φ
PWith the array element that is positioned at the origin of coordinates is benchmark, and each signal source is respectively s at the complex envelope of datum mark
1(t), s
2(t) ..., s
P(t).As shown in Figure 1, n the position of array element on the xy plane with vector representation is
The unit vector of direction of arrival is (u
i, v
i, cos θ
i), u
i=sin θ
iCos φ
i, v
i=sin θ
iSin φ
i, θ
iBe the angle of pitch, φ
iFor the azimuth (i=1,2 ..., P).D
nBeing projected as on the direction of arrival vector
The array factor of logarithm spiral battle array is:
Amplitude weighting function I in the array factor equation
n(n=1,2 ..., N) can be the even battle array that equates, also can be by certain changes in distribution (Taylor distributes as circle).For even battle array, its excitation amplitude I
n=I
0=1, excitation phase α
n=0.Because this array is at x, the y direction presents characteristic aperiodic, thereby, eliminated the condition that graing lobe produces.
Claims (3)
1. logarithm helical array antenna method of structuring the formation, it is characterized in that: antenna array adopts N bar logarithm spiral to structure the formation, N=2,3,4..., wall scroll log spiral equation is
Antenna element is in logarithm spiral equation
On, r,
Be any some position coordinates under polar coordinates on the log spiral, r is the relative wavelength number for a distance to the origin of coordinates,
Be the angle with respect to 0 ° of pole axis, a is the parameter of log spiral equation, is optimized a＞0.1 according to the beamwidth of antenna pattern, the needs of minor level technical indicator during array design; Antenna element n on every logarithm spiral is positioned at along the helix equation
The place, phase difference is between adjacent cells
N bar helix rotates 360 °/N around rotating shaft successively, and the r of each bar log spiral initial starting point is identical, and the phase place of first antenna element initial starting point is on every helix
Be separated by successively from initial starting point on every helix
Each places m array element respectively, when parameter a,
When determining, array manifold is just definite fully, and the total antenna element number of N bar logarithm helical array is Nm.
2. the logarithm helical array antenna according to claim 1 method of structuring the formation, it is characterized in that: array center is that an array element can be placed by the initial point place, the total antenna element number of N bar logarithm helical array this moment is Nm+1; Described logarithm spiral battle array is that sweep mutually or non-ly to sweep r mutually
n,
Antenna element can be placed by the place, also can place the antenna submatrix.
3. the logarithm helical array antenna according to claim 1 and 2 method of structuring the formation is characterized in that: in order to obtain best array layout, avoid occurring false spectrum peak, can adopt optimization method to parameter a,
Be optimized and dispose antenna array, promptly adopt the various optimized Algorithm comprise genetic algorithm, ant group algorithm, particle swarm optimization algorithm, to the parameter a that influence the antenna pattern variation,
Be optimized.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103513225A (en) * | 2013-09-22 | 2014-01-15 | 西安电子科技大学 | Sparse planar formation optimization method based on spatial gain |
| CN104267400A (en) * | 2014-10-21 | 2015-01-07 | 内蒙古工业大学 | Microwave signal transmitting-receiving system, method and imaging system for MIMO-SAR imaging |
| CN104409853A (en) * | 2014-11-27 | 2015-03-11 | 中国船舶重工集团公司第七二四研究所 | Method for controlling electric scanning beam shape of planar array antenna |
| CN104900988A (en) * | 2015-05-21 | 2015-09-09 | 电子科技大学 | Method for designing thin cloth circular antenna array through changing auxiliary grid circle radius |
| CN106443571A (en) * | 2016-09-05 | 2017-02-22 | 东南大学 | Conformal mapping estimation of signal parameters via rotational invariance technique DOA estimation method |
| CN107636896A (en) * | 2015-03-05 | 2018-01-26 | 集美塔公司 | Antenna element for cylindrical feed antenna is arranged |
| CN108256696A (en) * | 2018-03-16 | 2018-07-06 | 电子科技大学 | A kind of bonding state prediction and the radar network antenna allocation method of particle group optimizing |
| CN105515629B (en) * | 2015-12-23 | 2018-09-28 | 东南大学 | A kind of LTE network coverage optimization method based on Modified particle swarm optimization |
| CN109612572A (en) * | 2018-11-14 | 2019-04-12 | 国网上海市电力公司 | For quickly identifying the device and method of high voltage reactor abnormal sound sound source position |
| CN110276127A (en) * | 2019-06-20 | 2019-09-24 | 清华大学深圳研究生院 | A kind of pneumatic software actuator statics control method of spiral type |
| CN111969332A (en) * | 2020-07-30 | 2020-11-20 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Sparse array arrangement method for large-space wide-angle scanning millimeter wave phased array antenna |
| CN114491876A (en) * | 2022-04-13 | 2022-05-13 | 杭州兆华电子股份有限公司 | Self-adaptive reconstruction array combining method and system for leakage acoustic detection array |
| WO2023279737A1 (en) * | 2021-07-06 | 2023-01-12 | 东南大学 | Multi-constraint millimeter-wave vehicle-mounted mimo radar antenna array design method, and apparatus |
| US20230194644A1 (en) * | 2021-12-17 | 2023-06-22 | The Boeing Company | Antennas for producing a variable phase response, angle-of-arrival sensors and methods for determining angle of arrival |
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| CN103513225B (en) * | 2013-09-22 | 2015-06-17 | 西安电子科技大学 | Sparse planar formation optimization method based on spatial gain |
| CN103513225A (en) * | 2013-09-22 | 2014-01-15 | 西安电子科技大学 | Sparse planar formation optimization method based on spatial gain |
| CN104267400A (en) * | 2014-10-21 | 2015-01-07 | 内蒙古工业大学 | Microwave signal transmitting-receiving system, method and imaging system for MIMO-SAR imaging |
| CN104409853A (en) * | 2014-11-27 | 2015-03-11 | 中国船舶重工集团公司第七二四研究所 | Method for controlling electric scanning beam shape of planar array antenna |
| CN107636896A (en) * | 2015-03-05 | 2018-01-26 | 集美塔公司 | Antenna element for cylindrical feed antenna is arranged |
| CN104900988A (en) * | 2015-05-21 | 2015-09-09 | 电子科技大学 | Method for designing thin cloth circular antenna array through changing auxiliary grid circle radius |
| CN105515629B (en) * | 2015-12-23 | 2018-09-28 | 东南大学 | A kind of LTE network coverage optimization method based on Modified particle swarm optimization |
| CN106443571A (en) * | 2016-09-05 | 2017-02-22 | 东南大学 | Conformal mapping estimation of signal parameters via rotational invariance technique DOA estimation method |
| CN108256696A (en) * | 2018-03-16 | 2018-07-06 | 电子科技大学 | A kind of bonding state prediction and the radar network antenna allocation method of particle group optimizing |
| CN108256696B (en) * | 2018-03-16 | 2021-10-26 | 电子科技大学 | Networking radar antenna configuration method combining state prediction and particle swarm optimization |
| CN109612572A (en) * | 2018-11-14 | 2019-04-12 | 国网上海市电力公司 | For quickly identifying the device and method of high voltage reactor abnormal sound sound source position |
| CN110276127A (en) * | 2019-06-20 | 2019-09-24 | 清华大学深圳研究生院 | A kind of pneumatic software actuator statics control method of spiral type |
| CN110276127B (en) * | 2019-06-20 | 2023-04-07 | 清华大学深圳研究生院 | Statics control method for spiral pneumatic soft actuator |
| CN111969332A (en) * | 2020-07-30 | 2020-11-20 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Sparse array arrangement method for large-space wide-angle scanning millimeter wave phased array antenna |
| WO2023279737A1 (en) * | 2021-07-06 | 2023-01-12 | 东南大学 | Multi-constraint millimeter-wave vehicle-mounted mimo radar antenna array design method, and apparatus |
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Application publication date: 20101229 |