CN104092024B - Direction backtracking system based on corner reflector antenna array - Google Patents
Direction backtracking system based on corner reflector antenna array Download PDFInfo
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- CN104092024B CN104092024B CN201410264704.XA CN201410264704A CN104092024B CN 104092024 B CN104092024 B CN 104092024B CN 201410264704 A CN201410264704 A CN 201410264704A CN 104092024 B CN104092024 B CN 104092024B
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Abstract
The invention discloses a direction backtracking system based on a corner reflector antenna array, and belongs to the technical field of radar and communication engineering. The direction backtracking system is composed of at least two plane antennal array plates which are perpendicular to each other, the distance between the plane antenna array plates accords with a far field relation, and each plane antenna array plate is composed of a plane radiation unit, a receiving and sending radio frequency channel and a digital frequency storage device. According to the direction backtracking system, direction backtracking of radio frequency signals is achieved by mirror reflection of multiple plane antenna arrays, and in the process of achieving direction backtracking, the signal incidence direction does not need to be measured or estimated; power control and delay modulation of backward signals are achieved by the active features of the plane antenna arrays and the function of the digital frequency storage device. The direction backtracking system is suitable for returning of common signals in a radar system and a positioning system without conducting direction estimation on information sources, and particularly suitable for suppressing and deception jamming in the electronic countermeasure field.
Description
Technical field
The invention belongs to communication, radar engineering technical field, particularly to a kind of direction based on corner reflector antenna array
Backtracking system.
Background technology
Direction backtracking refers to for the electromagnetic signal receiving to pass through former being back reflected.The realization side of direction backtracking system
Formula is divided into active mode and two kinds of passive mode.Conventional radar reflector in passive direction backtracking system such as radar engineering
(also known as corner reflector), active orientation backtracking system is generally realized with the mode of aerial array, mainly has vanatta battle array at present
With two kinds of implementations of phase conjugation battle array (pon battle array).Vanatta battle array is by the multiple and centrosymmetric antenna element pair of array geometry
Composition, each pair antenna element is connected with identical electrical length transmission line.Phase conjugation battle array is based on frequency mixing technique and realizes.Radiofrequency signal
Be mixed with the local oscillator with twice carrier frequency, after mixing the sideband portion of the number of winning the confidence or have identical load with former radiofrequency signal
Frequently, but the radiofrequency signal of phase conjugation.
In passive radar reflector, the metal electricity wall of radar reflector carries out direct reflection, radiofrequency signal to radio frequency
After three times (or twice) reflection, return along incident direction.Metal electricity wall can also adopt to the reflection characteristic of radiofrequency signal
Active aerial array is realized, and active antenna array is gone out by primary antenna unit forwards after receiving radiofrequency signal again, forwards letter
Number sensing with incident direction, direct reflection relation is become for axis of symmetry with the normal direction of aerial array.Radiofrequency signal passes through aerial array
After carrying out three times (or twice) reflection, can return along incident direction.
Digital frequency memory technique (digital radio frequency memory, drfm) is at present in electronic countermeasure neck
A kind of wide variety of technology in domain.Digital frequency memory device is stored by the radiofrequency signal of simulation is converted to digital signal, and
On demand signal is modulated, time delay.Again analogue signal is changed into by digital to analog converter, and carries out frequency up-conversion operation recovery
For radiofrequency signal.Digital frequency memory device can be used as the signal source carrying out Deceiving interference in electronic countermeasure.
But, passive radar transmitter echo power is low, and a reflected energy is it is impossible to adjust the transmitting work(of radio-frequency (RF) energy
Rate；Active vanatta battle array etc. electrical length feeding network design more complicated；Active phase conjugation battle array is reached simultaneously
The impact of multiple-frequency signal and broadband signal is larger.
Content of the invention
In order to solve above-mentioned technical problem, the invention provides a kind of direction backtracking system based on corner reflector antenna array
System.This system realizes the direct reflection of radiofrequency signal in the way of aerial array, and the position by the multiple aerial arrays of design is complete
The in pairs direction backtracking of radiofrequency signal, during realizing direction backtracking it is not necessary to signal incident direction is measured or
Estimate, and be controlled direction backtracking system.
In order to achieve the above object, the present invention adopts the following technical scheme that: a kind of side based on corner reflector antenna array
To backtracking system, it is made up of at least two blocks of orthogonal planar array antenna strakes, the distance between planar array antenna strake is full
Sufficient far field relation.
Described planar array antenna strake is made up of planar radiating element, radio-frequency channel and digital frequency memory device, described plane sky
Each antenna element on linear array strake is respectively connected with radio-frequency channel, the other end of described radio-frequency channel and digital frequency memory device phase
Even.
Each radio-frequency channel described is divided into receiving portion and emitting portion, and the receiving portion composition of radio-frequency channel includes duplex
Device, low-noise amplifier, receiving terminal radio frequency band filter, low-converter, if bandpas filter；The emission part of radio-frequency channel
Divide and include if bandpas filter, upconverter, radio frequency band filter, power amplifier, duplexer.
Described digital frequency memory device include analog-digital converter, CPLD, memorizer, digital to analog converter,
Power supply and clock unit；Wherein, the radiofrequency signal of simulation is converted to the incoming complex programmable of digital signal and patrols by analog-digital converter
Collect device, be converted to analogue signal through the process of CPLD through digital to analog converter and transfer out；Memorizer
Digital signal in storage CPLD；Clock unit provides stable arteries and veins for CPLD
Punching；Power supply is that entirely digital frequency memory device is powered.
Described planar array antenna strake has three pieces；Or planar array antenna strake has two pieces.
Described planar array antenna strake is rectangle or circle.
The present invention provides a kind of direction backtracking system based on corner reflector antenna array, this system can by incident one or
Multiple radiofrequency signals reflect back along incident direction, and make use of digital frequency memory technique, and the radiofrequency signal that receive can be adjusted
System, fixed response time when etc. operation.
Active with respect to existing passive radar reflector system at present and vanatta battle array, phase conjugation battle array both
Direction backtracking system, the invention has the advantages that
1) relatively passive radar transmitter, the present invention can be processed to radiofrequency signal, and the forwarding time of signal is
Controlled；The present invention has higher echo power, and radio-frequency echo wave can be modulated；Passive radar transmitter only reflects energy
Amount, and the present invention can design the transmission power of radio-frequency (RF) energy as needed；The passive signal of radar reflector transmitting and former letter
Number it is same signal, and the present invention can be processed to echo-signal, and this characteristic is particularly suited for Radar ECM engineering
In field.
2) with respect to vanatta battle array, the present invention does not need to design the feeding network of the electrical length such as complicated；Due to each
The receive-transmit system of antenna element is independent subsystem, more conducively modular design, and vanatta battle array does not possess the present invention's
Radiofrequency signal is modulated with the ability processed.
3) with respect to phase conjugation battle array, the present invention is not affected by the multiple-frequency signal reaching, broadband signal simultaneously；Need not
Accurate estimation to CF signal, and there is the ability that multiple radiofrequency signals are recalled simultaneously；In broadband signal or multiple-frequency signal
During arrival, phase conjugation battle array loses direction backdating capability, and the direction backdating capability of the present invention is only relevant with the bandwidth of antenna element,
All signals in the beamwidth of antenna all can complete direction backtracking.
Brief description
Fig. 1 is the structural representation of the embodiment of the present invention one.
Fig. 2 is the structured flowchart of midplane antenna array strake of the present invention.
Fig. 3 is the radio-frequency channel of midplane antenna array strake of the present invention and the structured flowchart of digital frequency memory device.
Fig. 4 is equiphase surface relation schematic diagram in radiofrequency signal incidence of the present invention and reflection process.
Fig. 5 is the structural representation of the embodiment of the present invention two.
Specific embodiment
To specifically describe the preferred embodiments of the present invention below in conjunction with the accompanying drawings, wherein, accompanying drawing constitutes the application part, and
It is used for together with embodiments of the present invention explaining the principle of the present invention.
Embodiment one
A kind of direction backtracking system based on corner reflector antenna array as shown in Figure 1, by the plane sky positioned at xoy plane
The planar array antenna strake 3 of linear array strake 1, the planar array antenna strake 2 of xoz plane and yoz plane forms, three pieces of flat plane antennas
Array board is mutually perpendicular to, and the distance between every two blocks of planar array antenna strakes meet far field condition, and that is, electromagnetic wave is away from radiation source
Distance meet relation:(The aperture of representative antennas,Represent the wavelength of electromagnetic wave).Three pieces of planar antenna array
The radiating surface of plate forms corner reflection structure.The working method of the antenna element on every block of planar array antenna strake is duplex, that is,
The signal that antenna element receives is gone out by this unit forwards after time delay or storage again.The shape of planar array antenna strake can be
Rectangle, circle or other any type of planes.
In this system, the structure of every block of planar array antenna strake includes planar radiating element 4, radio-frequency channel 5 and digital frequency memory
Device 6, as shown in Figure 2.Radio-frequency channel 5 is as shown in Figure 3 with annexation with the structure of digital frequency memory device 6.Each radio-frequency channel 5 is again
Receiving portion and emitting portion can be divided into, wherein receiving portion includes duplexer 7, low-noise amplifier (lna) 8, receives end-fire
Band-pass filter (bpf) 9, low-converter 10, reception if bandpas filter (bpf) 12；Emitting portion includes emission medium-frequency
Band filter (bpf) 12, upconverter 10, transmitting radio frequency band filter (bpf) 8, power amplifier (pa) 13, duplexer
7.Duplexer 7 is to receive to share with emitting portion, and local oscillator 11 is upconverter or the derived reference signal of low-converter 10.Numeral
The structure of frequency memory device 6 includes analog-digital converter (adc) 14, digital to analog converter (dac) 15, CPLD (cpld)
16th, power supply 17, memorizer 18 and clock unit 19.
Its work process is: when radiofrequency signal incides planar array antenna strake 1 from far field, is led to by the radio frequency in 1
The forwarding of the reflecting part of the reception of the receiving portion in road 5, the storage of digital frequency memory device 6 and radio-frequency channel 5, wherein, in radio frequency
In passage 5, signal is exaggerated, and radiofrequency signal edge becomes the direction of direct reflection relation to project with this planar antenna array normal direction；Project
Signal reach the planar array antenna strake 2 vertical with planar array antenna strake 1, by the receiving portion of the radio-frequency channel 5 in 2
Reception, digital frequency memory device 6 store again and radio-frequency channel 2 reflecting part forwarding；Radiofrequency signal reaches and flat plane antenna
The all vertical planar array antenna strake 3 of array board 1 and 2, finally, by the reception of the receiving portion of radio-frequency channel 5, numeral in 3
The forwarding of the reflecting part of the storage of frequency memory device 6 and radio-frequency channel 5, radiofrequency signal returns along incident direction, it is achieved thereby that penetrating
The orientation backtracking of frequency signal.The process of radiofrequency signal reflection is as shown by the arrows in Figure 1.
If the radiofrequency signal carrier frequency of a certain x wave band airborne radar transmitting is 10ghz, the angle of pitch of the direction of the launch and azimuth
It is respectivelyWith.Selected zero o, by the center of three blocks of planar array antenna strakes be individually positioned in coordinate be (5,5,
0), on the point of (5,0,5) and (0,5,5), and the radiating surface of three blocks of planar array antenna strakes is mutually perpendicular to, wherein coordinate
Unit is rice.Element number of array on every block of planar array antenna strake is 25(5 × 5), the array element distance on x direction and y direction is
Half-wavelength (1.5cm).
Polar coordinate are converted to rectangular coordinate, obtain the unit vector of incident direction under rectangular coordinate system:
Incoming signal equiphase surface 20 as shown in Figure 4 and the relation of reflected signal equiphase surface 21, radiofrequency signal is passed through
After planar array antenna strake 1 reflection in xoy plane, the incident direction of signal is changed into:
If now after first time direct reflection, radiofrequency signal incides the planar array antenna strake 2 in xoz plane
On, again pass by direct reflection, the incident direction of signal is changed into:
For meeting minute surface relation, now signal will incide on the planar array antenna strake 3 in yoz plane, for the third time
After direct reflection, the exit direction of signal is changed into:
The unit vector of exit direction is converted under polar coordinate, obtains through corner reflector antenna array direction backtracking system
Afterwards, the angle of pitch of the exit direction of signal and azimuth are respectivelyWith.Compared with the incident direction of signal, outgoing
Signal returns along the direction of incoming signal.
In the present embodiment, if signal is respectively through the time delay of three blocks of planar array antenna strakes, then this system
Total time delay:
Using(Represent the light velocity), obtain the distance value of range gate deception in electronic countermeasure, therefore can be utilized and always prolong
WhenValue is setting the distance value of range gate deception in electronic countermeasure.
Embodiment two
A kind of direction backtracking system based on corner reflector antenna array, as shown in figure 5, by two pieces of orthogonal planar arrays
Strake 1 and 2 forms, and the distance between two blocks of planar array antenna strakes meet far field condition(The hole of representative antennas
Footpath,Represent the wavelength of electromagnetic wave), the radiating surface of two blocks of planar array antenna strakes forms corner reflection structure, and plane of incidence 22 is such as
Shown in Fig. 5.In this system, the structure of the structure of every block of planar array antenna strake, radio-frequency channel 5 and digital frequency memory device 6 and connection are closed
System is with embodiment one.Radiofrequency signal realizes the process of orientation backtracking as shown by the arrows in Figure 5.On every block of planar array antenna strake
The working method of antenna element is duplex, and the signal that is, antenna element receives is turned by this unit after time delay or storage again
Send.Wherein, the shape of planar array antenna strake can be rectangle, circular or other any type of planes.
This improvement project is applied to satellite, civil aviaton etc. and has fixing track or course line and it needs to carry out orientation backtracking
In system.Modulate the position of orthogonal antenna array strake so as to vertical with the plane that fixing track or course line are located, then
Only need two secondary reflections can recall to complete the direction of radiofrequency signal.
Embodiment three
A kind of direction backtracking system based on corner reflector antenna array, is made up of at least two blocks of planar array antenna strakes, often
Two blocks of planar array antenna strakes are mutually perpendicular to, and the distance between every two blocks of planar array antenna strakes meet far field condition, i.e. electricity
The distance away from radiation source for the magnetic wave meets relation:(The aperture of representative antennas,Represent the wavelength of electromagnetic wave), plane
The radiating surface of antenna array strake forms corner reflection structure.The working method of the antenna element on every block of planar array antenna strake is double
Work, the signal that is, antenna element receives is gone out by this unit forwards after time delay or storage again.
In this system, the structure of a certain piece or certain two blocks of planar array antenna strake includes planar radiating element 4, radio-frequency channel 5
And the phase shifter, one end of radio-frequency channel 5 is connected with planar radiating element 4, and the other end was connected with the phase shifter.Other structures and work
Process is with embodiment one.
In the present embodiment the phase shifter can be delay line or other there is the device of delay action.
This improvement project still retention figures frequency memory device is for abilities such as the modulation of signal, time delays, but decreases numeral
The use number of frequency memory device, can reduce the cost of system.
Example IV
A kind of direction backtracking system based on corner reflector antenna array, is made up of at least two blocks of planar array antenna strakes, often
Two blocks of planar array antenna strakes are mutually perpendicular to, and the distance between every two blocks of planar array antenna strakes meet far field condition, i.e. electricity
The distance away from radiation source for the magnetic wave meets relation:(The aperture of representative antennas,Represent the wavelength of electromagnetic wave), plane
The radiating surface of antenna array strake forms corner reflection structure.The working method of the antenna element on every block of planar array antenna strake is double
Work, the signal that is, antenna element receives is gone out by this unit forwards after time delay or storage again.
In this system, the structure of every block of planar array antenna strake includes planar radiating element 4, radio-frequency channel 5 and digital frequency memory
Device 6, one end of radio-frequency channel 5 is connected with planar radiating element 4, and the other end is connected with digital frequency memory device 5.
In radio-frequency channel 5, the gain of the power amplifier 13 of the low-noise amplifier 8 of receiving portion and emitting portion is can
Become.Other structures and work process are with embodiment one.
The program is equivalent to the amplitude to radiofrequency signal and is weighted, and can reduce secondary lobe electricity by weights reasonable in design
Flat, reduce interference.
Above example is merely to illustrate the preferred embodiment of the present invention, but the present invention is not limited to above-mentioned embodiment party
Formula.Above example to those skilled in the art provide the present invention basic function description, and make it easier to understand
With the application present invention.For those skilled in the art, the present embodiment is carried out transplanting to be made to carry out various changes to it to be even more
It will be apparent that without performing creative labour.Therefore, right of the present invention does not limit the scheme described in above example, and
With consistent described in claims.
Claims (6)
1. a kind of direction backtracking system based on corner reflector antenna array is it is characterised in that by least two pieces of orthogonal planes
Antenna array strake forms, and the distance between planar array antenna strake meets far field relation:, whereindRepresentative antennas
Aperture,Represent the wavelength of electromagnetic wave；The radiating surface of every block of planar array antenna strake forms corner reflection structure；Described flat plane antenna
Array board is made up of planar radiating element, radio-frequency channel and digital frequency memory device, each plane on described planar array antenna strake
Radiating element is respectively connected with radio-frequency channel, and the other end of described radio-frequency channel is connected with digital frequency memory device；Each described radio frequency
Passage is divided into receiving portion and emitting portion, and the receiving portion of radio-frequency channel includes duplexer, the low noise amplification being sequentially connected
Device, receiving terminal radio frequency band filter, low-converter, if bandpas filter；The emitting portion of radio-frequency channel includes connecting successively
The if bandpas filter that connects, upconverter, radio frequency band filter, power amplifier, duplexer, if bandpas filter with
Digital frequency memory device is connected, the low-converter of radio-frequency channel receiving portion, radio-frequency channel emitting portion upconverter all with this
Shake and be connected.
2. the direction backtracking system based on corner reflector antenna array according to claim 1 it is characterised in that: described numeral
Frequency memory device includes analog-digital converter, CPLD, memorizer, digital to analog converter, power supply and clock unit；Its
In, the radiofrequency signal of simulation is converted to the incoming CPLD of digital signal by analog-digital converter, can through complexity
The process of programmed logic device is converted to analogue signal through digital to analog converter and transfers out；Memory storage complex programmable logic
Digital signal in device；Clock unit provides stable pulse for CPLD；Power supply is entirely numeral storage
Frequency device is powered.
3. the direction backtracking system based on corner reflector antenna array according to claim 1 it is characterised in that: described plane
Antenna array strake has three pieces.
4. the direction backtracking system based on corner reflector antenna array according to claim 1 it is characterised in that: described plane
Antenna array strake has two pieces.
5. the direction backtracking system based on corner reflector antenna array according to claim 1 it is characterised in that: described plane
Antenna array strake is rectangle.
6. the direction backtracking system based on corner reflector antenna array according to claim 1 it is characterised in that: described plane
Antenna array strake is circle.
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| CN201410264704.XA CN104092024B (en) | 2014-06-16 | 2014-06-16 | Direction backtracking system based on corner reflector antenna array |
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| CN104092024B true CN104092024B (en) | 2017-01-18 |
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Families Citing this family (3)
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| GB2541036B (en) * | 2015-08-07 | 2019-03-27 | Zwipe As | Power optimisation |
| CN111430932B (en) * | 2020-04-09 | 2021-09-03 | 南京理工大学 | Polarization torsion active angle reflection direction backtracking system |
| CN113030879A (en) * | 2021-03-09 | 2021-06-25 | 中国人民解放军国防科技大学 | Low-profile plane retroreflector with echo amplitude control function |
Citations (2)
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|---|---|---|---|---|
| CN103001005A (en) * | 2012-10-25 | 2013-03-27 | 中兴通讯股份有限公司 | Device and mobile terminal for lowering specific absorption rate of electromagnetic radiation |
| CN203552248U (en) * | 2013-10-04 | 2014-04-16 | 南京长峰航天电子科技有限公司 | High-bit rate broadband digital frequency memory |
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2014
- 2014-06-16 CN CN201410264704.XA patent/CN104092024B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103001005A (en) * | 2012-10-25 | 2013-03-27 | 中兴通讯股份有限公司 | Device and mobile terminal for lowering specific absorption rate of electromagnetic radiation |
| CN203552248U (en) * | 2013-10-04 | 2014-04-16 | 南京长峰航天电子科技有限公司 | High-bit rate broadband digital frequency memory |
Non-Patent Citations (1)
| Title |
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| 方向回溯天线阵研究;郭玉春;《中国博士学位论文全文数据库》;20110415;第21-23页 * |
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