CN107678030A - A kind of unmanned plane obstacle avoidance system based on millimetre-wave radar - Google Patents
A kind of unmanned plane obstacle avoidance system based on millimetre-wave radar Download PDFInfo
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- CN107678030A CN107678030A CN201711045385.3A CN201711045385A CN107678030A CN 107678030 A CN107678030 A CN 107678030A CN 201711045385 A CN201711045385 A CN 201711045385A CN 107678030 A CN107678030 A CN 107678030A
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- signal
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- unmanned plane
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
- G01S13/933—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of aircraft or spacecraft
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D1/00—Control of position, course or altitude of land, water, air, or space vehicles, e.g. automatic pilot
- G05D1/10—Simultaneous control of position or course in three dimensions
- G05D1/101—Simultaneous control of position or course in three dimensions specially adapted for aircraft
Abstract
The invention discloses a kind of unmanned plane obstacle avoidance system based on millimetre-wave radar, and it includes at least one unmanned plane and monitoring unmanned center；Unmanned plane is carried out data transmission by wireless transmission method and monitoring unmanned center；Unmanned plane includes unmanned plane body and control device；Control device is arranged on the unmanned plane body；Control device includes microprocessor, memory, the first signal transmitting and receiving module, image capture module, image processing module, power module and millimeter wave avoidance radar；Microprocessor is connected with each other with the memory, the first signal transmitting and receiving module and millimeter wave avoidance radar；The output end of power module is connected with the energization input of the microprocessor, image processing module, image capture module, millimeter wave avoidance radar；The output end of image capture module and the input of image processing module connect；The output end of image processing module and the input of microprocessor connect.
Description
Technical field
The present invention relates to unmanned air vehicle technique field, more particularly to a kind of unmanned plane obstacle avoidance system based on millimetre-wave radar.
Background technology
Unmanned plane is just being used for the multiple fields such as military affairs, agricultural, Aero-Space, wireless sensing as a new industry
Or industry；And then traditional unmanned plane avoidance passes through figure only simply by the image in front of camera collection unmanned plane
Judge whether front has barrier as analysis；This mode one is that accuracy remains to be discussed, second, the front of camera collection
Limited view, if unmanned plane speed is too fast graphical analysis can be caused to lag and cause unmanned plane avoidance not ask in time
Topic.
So how to judge that unmanned plane avoidance is improved in front on the basis of having clear by IMAQ analysis
Promptness and barrier judgment accuracy be need consider the problem of.
The content of the invention
It is an object of the invention to overcome the deficiencies of the prior art and provide a kind of unmanned plane avoidance based on millimetre-wave radar
System, solve the problems, such as that existing unmanned plane avoidance is not high with barrier judgment accuracy not in time.
The purpose of the present invention is achieved through the following technical solutions：A kind of unmanned plane avoidance based on millimetre-wave radar
System, it includes at least one unmanned plane and monitoring unmanned center；Unmanned plane passes through wireless transmission method and monitoring unmanned
Center carries out data transmission；Unmanned plane includes unmanned plane body and control device；Control device is arranged on the unmanned plane body
On；Control device includes microprocessor, memory, the first signal transmitting and receiving module, image capture module, image processing module, electricity
Source module and millimeter wave avoidance radar；Microprocessor and the memory, the first signal transmitting and receiving module and millimeter wave avoidance radar
It is connected with each other；The output end of power module and the microprocessor, image processing module, image capture module, millimeter wave avoidance
The energization input connection of radar；The output end of image capture module and the input of image processing module connect；Image procossing
The output end of module and the input of microprocessor connect.
Monitoring unmanned center includes central processing unit, display module, dual-mode antenna, storage server and secondary signal and received
Send out module；Central processing unit is connected with each other with signal transmitting and receiving module；The data output end of central processing unit and storage server
Data input pin connects；The audio signal output end of central processing unit and the input of display module connect；Secondary signal is received and dispatched
The signal output part of module and the input of display module connect；Secondary signal transceiver module is connected with each other with dual-mode antenna.
Millimeter wave avoidance radar includes signal processing module, display module, power module, rf integration module, transmitting day
Line and at least two reception antennas；The signal output part of signal processing module is connected with the signal input part of rf integration module；
The data processing output end of signal processing module and the input of display module connect；The signal output part hair of rf integration module
The output signal gone out is connected with transmitting antenna；The signal input part of the echo-signal that reception antenna receives and rf integration module connects
Connect；Feeder ear of the power module respectively with signal processing module, rf integration module and display module is connected.
Signal processing module include clock circuit, FPGA unit, DSP unit, ADC, DAC, filter unit, AGC unit and
First power amplification unit；The output end of clock circuit and the clock signal input terminal of FPGA unit connect；The letter of FPGA unit
The signal input part of number output end and DSP unit connects；The signal output part of DSP unit and DAC signal input part connect；
DAC signal output part is connected with the signal input part of rf integration module；The signal output part of first power amplification unit with
AGC unit connects with the signal input part of filter unit；The signal of the signal output part of AGC unit and the first power amplification unit
Input connects；The signal output part of filter unit and ADC signal input part connect；ADC signal output part and FPGA are mono-
The signal input part connection of member.
Rf integration module include VCO unit, the second power amplification unit, low noise amplification unit, beat processing unit,
Frequency mixer and phase comparator；The signal output part of VCO unit is connected with the signal input part of the second power amplification unit；Second
The signal output part of power amplification unit is connected with transmitting antenna；Reception antenna is connected with the signal input part of the frequency mixer；
The signal output part of frequency mixer and the signal input part of phase comparator connect；The output end and low noise amplification of phase comparator
The input connection of device；Signal input part of the signal output part of second power amplification unit also with beat processing unit is connected；
The first power amplification unit in the signal output part and signal processing module of beat processing unit in rf integration module
Signal input part connects.
Image capture module includes at least one high-definition camera；The image of shooting is sent at image by high-definition camera
Manage in module.
First signal transmitting and receiving module includes the first signal receiving unit and the first signal transmitter unit；First signal receives single
The output end of member and the signal input part of microprocessor connect；The signal output part of microprocessor and the first signal transmitter unit
Input connects.
Secondary signal transceiver module includes secondary signal receiving unit and secondary signal transmitter unit；Secondary signal receives single
The output end of member and the signal input part of central processing unit connect；The signal output part of central processing unit and secondary signal transmitting are single
The input connection of member.
First signal transmitting and receiving module enters row data communication by dual-mode antenna and secondary signal transceiver module.
The beneficial effects of the invention are as follows：A kind of unmanned plane obstacle avoidance system based on millimetre-wave radar, can pass through millimeter wave
On the basis of avoidance radar surveying has clear, recycle IMAQ analysis to carry out the specifying information realization of cognitive disorders thing and keep away
Hinder function, drastically increase the avoidance promptness of unmanned plane and the accuracy of avoidance, ensure that the flight safety of unmanned plane.
Brief description of the drawings
Fig. 1 is the structured flowchart of system；
Fig. 2 is the structure chart of millimeter wave avoidance radar；
Fig. 3 is the time-frequency schematic diagram of triangular signal beat processing；
Fig. 4 is that the triangular signal beat containing Doppler frequency handles time-frequency schematic diagram；
Fig. 5 is phase method angle measuring principle figure.
Embodiment
Technical scheme is described in further detail below in conjunction with the accompanying drawings, but protection scope of the present invention is not limited to
It is as described below.
As shown in figure 1, a kind of unmanned plane obstacle avoidance system based on millimetre-wave radar, it includes at least one unmanned plane and nothing
Man-machine Surveillance center；Unmanned plane is carried out data transmission by wireless transmission method and monitoring unmanned center；Unmanned plane includes nothing
Man-machine body and control device；Control device is arranged on the unmanned plane body；Control device includes microprocessor, storage
Device, the first signal transmitting and receiving module, image capture module, image processing module, power module and millimeter wave avoidance radar；Microprocessor
Device is connected with each other with the memory, the first signal transmitting and receiving module and millimeter wave avoidance radar；The output end of power module and institute
State the energization input connection of microprocessor, image processing module, image capture module, millimeter wave avoidance radar；IMAQ
The output end of module and the input of image processing module connect；The output end of image processing module and the input of microprocessor
Connection.
Preferably, monitoring unmanned center includes central processing unit, display module, dual-mode antenna, storage server and the
Binary signal transceiver module；Central processing unit is connected with each other with signal transmitting and receiving module；The data output end of central processing unit and storage
The data input pin connection of server；The audio signal output end of central processing unit and the input of display module connect；Second
The signal output part of signal transmitting and receiving module and the input of display module connect；Secondary signal transceiver module and dual-mode antenna are mutual
Connection.
Preferably, as shown in Fig. 2 millimeter wave avoidance radar includes signal processing module, display module, power module, penetrated
Frequency integration module, transmitting antenna and at least two reception antennas；The signal output part of signal processing module and rf integration module
Signal input part connection；The data processing output end of message processing module and the input of display module connect；Rf integration
The output signal that the signal output part of module is sent is connected with transmitting antenna；The echo-signal and rf integration that reception antenna receives
The signal input part connection of module；The power module power supply with signal processing module, rf integration module and display module respectively
End connection.
Preferably, signal processing module includes clock circuit, FPGA unit, DSP unit, ADC, DAC, filter unit, AGC
Unit and the first power amplification unit；The output end of clock circuit and the clock signal input terminal of FPGA unit connect；FPGA is mono-
The signal output part of member and the signal input part of DSP unit connect；The signal output part of DSP unit and DAC signal input part
Connection；DAC signal output part is connected with the signal input part of rf integration module；The signal output of first power amplification unit
End is connected with the signal input part of AGC unit；The signal output part of AGC unit and the signal input part of filter unit connect；Filter
The signal output part of ripple unit and ADC signal input part connect；ADC signal output part and the signal input part of FPGA unit
Connection.
Preferably, rf integration module include VCO unit, the second power amplification unit, low noise amplification unit, at beat
Manage unit, frequency mixer and phase comparator；The signal input part of the signal output part of VCO unit and the second power amplification unit connects
Connect；The signal output part of second power amplification unit is connected with transmitting antenna；The signal of reception antenna and the frequency mixer inputs
End connection；The signal output part of frequency mixer and the signal input part of phase comparator connect；The output end of phase comparator with it is low
The input connection of noise amplifier；The signal output part of second power amplification unit also inputs with the signal of beat processing unit
End connection；The first power amplification in the signal output part and signal processing module of beat processing unit in rf integration module
The signal input part connection of unit.
Preferably, image capture module includes at least one high-definition camera；High-definition camera transmits the image of shooting
Into image processing module.
Preferably, the first signal transmitting and receiving module includes the first signal receiving unit and the first signal transmitter unit；First letter
The output end of number receiving unit and the signal input part of microprocessor connect；The signal output part of microprocessor and the first signal are sent out
Penetrate the input connection of unit.
Preferably, secondary signal transceiver module includes secondary signal receiving unit and secondary signal transmitter unit；Second letter
The output end of number receiving unit and the signal input part of central processing unit connect；The signal output part of central processing unit and the second letter
The input connection of number transmitter unit.
Preferably, the first signal transmitting and receiving module enters row data communication by dual-mode antenna and secondary signal transceiver module.
Preferably, the workflow of system ranging is：After minimizing radar system power-up, when crystal oscillator provides benchmark for FPGA
Clock signal, clock signal is divided by FPGA, then after carrying out signal transacting by DSP, deliver to ADC and DAC respectively, and by
FPGA produces discrete Serial No. and send DAC, is converted to analog control signal, controls the VCO in rf integration unit, and output needs
The triangular modulation signal wanted, and amplified, antennas transmitting.Reception antenna receives target echo signal, in rf integration
After carrying out low noise amplification in unit, beat processing is done with transmission signal, output beat intermediate-freuqncy signal send signal processing unit, according to
It is secondary be amplified, filter and ADC sampling processings after, send FPGA extract and FFT processing, estimate the frequency of beat intermediate-freuqncy signal
Rate, the distance of target can be calculated using the frequency values.
Preferably, millimeter wave range radar passes through target echo and transmission signal using transmitting continuous wave signal (FMCW)
Beat processing, obtain the single-carrier signal related to target range, frequency values and the target range value of single-carrier signal are formed
Mapping relations one by one.Launch FMCW signal for ease of system, complete target distance measurement, while can also realize that target velocity is surveyed
Amount, the FMCW signal of miniaturization radar system transmitting are intended using triangular wave patterns.
As shown in figure 3, Δ F is the bandwidth of triangle arm signal in figure, T represents the cycle of triangle arm signal, and τ is
The time delay of echo-signal, then beat signal frequency fbIt is with delay time relation：
Delay time τ=2R/c is substituted into above equation, the accounting equation that can obtain target range R is：
It was found from from above equation, the range measurement of target is directly proportional to the cycle of triangular signal, beat signal frequency,
It is inversely proportional with signal bandwidth, after being determined with bandwidth in the cycle of triangular signal, distance is more remote, then beat signal frequency is got over
It is high.
Millimeter wave range radar will meet the transmitting of the object ranging requirement, first millimeter wave range radar to certain distance
Power needs to meet radar equation, i.e.,
In formula, PtFor the transmission power of millimeter wave range radar, GtAnd GrIt is the increasing of transmitting antenna and reception antenna respectively
Benefit, σ are the radar scattering areas of target, and λ is the wavelength for launching triangular signal, the bandwidth of operation of B receivers, K be Bohr hereby
Graceful constant, T0It is noise temperature, NF is the noise coefficient of radar, (S/N)minIt is the minimum detectable signal-to-noise ratio of radar.
If target is in motion, in the echo-signal after target reflects, in addition to one the relative fortune by target
Move caused Doppler frequency fd, the relationship between frequency and time figure of its beat is as shown in Figure 3.
From in figure, selecting triangular signal to carry out beat processing, its rising edge and trailing edge beat are frequent in going out
Rate is different, and output IF-FRE is expressed as：
fb-=fb-fd
fb+=fb+fd
In formula：fbIt is Beat Signal output frequency when target is in relative static conditions, fb-It is that triangular wave rising edge is poor
Clap output signal frequency, fb+It is triangular wave trailing edge beat output signal frequency.
Then Beat Signal Doppler frequency fdFor：
According to doppler principle, the speed of related movement of target is：
In formula：λ represents the wavelength of transmitting triangular signal.
According to above equation, test the speed the whole cycle needed using triangular signal, could obtain fb+And fb-。
Preferably, mainly entered by phase method angle measurement using the phase difference between multiple reception antenna institutes receives echo-signal
Row angle measurement.
As shown in figure 5, being located at θ directions has a far field target, then the electric wave that the target of arrival receiving point is launched is approximately
Plane wave.Because two antenna spacing are d, so the signal that they are received produces a phase due to wave path-difference Δ R be present
Difference
Wherein λ is radar wavelength.Carry out, than phase, measuring its phase difference by using phase comparatorIt is assured that target
Direction θ.
Described above is only the preferred embodiment of the present invention, it should be understood that the present invention is not limited to described herein
Form, the exclusion to other embodiment is not to be taken as, and can be used for various other combinations, modification and environment, and can be at this
In the text contemplated scope, it is modified by the technology or knowledge of above-mentioned teaching or association area.And those skilled in the art are entered
Capable change and change does not depart from the spirit and scope of the present invention, then all should be in the protection domain of appended claims of the present invention
It is interior.
Claims (9)
- A kind of 1. unmanned plane obstacle avoidance system based on millimetre-wave radar, it is characterised in that：It includes at least one unmanned plane and nothing Man-machine Surveillance center；Described unmanned plane is carried out data transmission by wireless transmission method and the monitoring unmanned center；Institute The unmanned plane stated includes unmanned plane body and control device；Described control device is arranged on the unmanned plane body；It is described Control device include microprocessor, memory, the first signal transmitting and receiving module, image capture module, image processing module, power supply Module and millimeter wave avoidance radar；Described microprocessor and the memory, the first signal transmitting and receiving module and millimeter wave avoidance Radar is connected with each other；The output end of described power module is adopted with the microprocessor, described image processing module, described image Collect the energization input connection of module, the millimeter wave avoidance radar；The output end of described image capture module and the figure As the input of processing module connects；The output end of described image processing module is connected with the input of the microprocessor.
- A kind of 2. unmanned plane obstacle avoidance system based on millimetre-wave radar according to claim 1, it is characterised in that：Described Monitoring unmanned center includes central processing unit, display module, dual-mode antenna, storage server and secondary signal transceiver module； Described central processing unit is connected with each other with the secondary signal transceiver module；The data output end of described central processing unit with The data input pin connection of the storage server；The audio signal output end of described central processing unit and the display module Input connection；The signal output part of described secondary signal transceiver module is connected with the input of the display module；Institute The secondary signal transceiver module stated is connected with each other with the dual-mode antenna.
- A kind of 3. unmanned plane obstacle avoidance system based on millimetre-wave radar according to claim 1, it is characterised in that：Described Millimeter wave avoidance radar includes signal processing module, display module, power module, rf integration module, transmitting antenna and at least Two reception antennas；The signal output part of described signal processing module and the signal input part of the rf integration module connect Connect；The data processing output end of described signal processing module is connected with the input of the display module；Described radio frequency is comprehensive The output signal that the signal output part of matched moulds block is sent is connected with the transmitting antenna；The echo letter that described reception antenna receives Number it is connected with the signal input part of the rf integration module；Described power module respectively with the signal processing module, institute The feeder ear that rf integration module is stated with the display module connects.
- A kind of 4. unmanned plane obstacle avoidance system based on millimetre-wave radar according to claim 3, it is characterised in that：Described Signal processing module includes clock circuit, FPGA unit, DSP unit, ADC, DAC, filter unit, AGC unit and the first power Amplifying unit；The output end of described clock circuit is connected with the clock signal input terminal of the FPGA unit；Described FPGA The signal output part of unit is connected with the signal input part of the DSP unit；The signal output part of described DSP unit with it is described DAC signal input part connection；Described DAC signal output part is connected with the signal input part of the rf integration module； The signal output part of the first described power amplification unit is connected with the signal input part of the AGC unit and filter unit；Institute The signal output part for the AGC unit stated is connected with the signal input part of first power amplification unit；Described filter unit Signal output part be connected with the signal input part of the ADC；Described ADC signal output part and the letter of the FPGA unit The connection of number input.
- A kind of 5. unmanned plane obstacle avoidance system based on millimetre-wave radar according to claim 4, it is characterised in that：Described Rf integration module include VCO unit, the second power amplification unit, low noise amplification unit, beat processing unit, frequency mixer and Phase comparator；The signal output part of described VCO unit is connected with the signal input part of second power amplification unit；Institute The signal output part for the second power amplification unit stated is connected with the transmitting antenna；Described reception antenna and the frequency mixer Signal input part connection；The signal output part of described frequency mixer is connected with the signal input part of the phase comparator；Institute The output end for the phase comparator stated is connected with the input of the low-noise amplifier；The second described power amplification unit Signal input part of the signal output part also with the beat processing unit is connected；Beat processing in described rf integration module The signal output part of unit is connected with the signal input part of the first power amplification unit in the signal processing module.
- A kind of 6. unmanned plane obstacle avoidance system based on millimetre-wave radar according to claim 1, it is characterised in that：Described Image capture module includes at least one high-definition camera；The image of shooting is sent to described image by described high-definition camera In processing module.
- A kind of 7. unmanned plane obstacle avoidance system based on millimetre-wave radar according to claim 2, it is characterised in that：Described First signal transmitting and receiving module includes the first signal receiving unit and the first signal transmitter unit；The first described signal receiving unit Output end be connected with the signal input part of the microprocessor；The signal output part of described microprocessor and the described first letter The input connection of number transmitter unit.
- A kind of 8. unmanned plane obstacle avoidance system based on millimetre-wave radar according to claim 7, it is characterised in that：Described Secondary signal transceiver module includes secondary signal receiving unit and secondary signal transmitter unit；Described secondary signal receiving unit Output end be connected with the signal input part of the central processing unit；The signal output part of described central processing unit and described the The input connection of binary signal transmitter unit.
- A kind of 9. unmanned plane obstacle avoidance system based on millimetre-wave radar according to claim 8, it is characterised in that：Described First signal transmitting and receiving module enters row data communication by dual-mode antenna and the secondary signal transceiver module.
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| CN201711045385.3A CN107678030A (en) | 2017-10-31 | 2017-10-31 | A kind of unmanned plane obstacle avoidance system based on millimetre-wave radar |
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| CN201711045385.3A CN107678030A (en) | 2017-10-31 | 2017-10-31 | A kind of unmanned plane obstacle avoidance system based on millimetre-wave radar |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111366929A (en) * | 2020-03-06 | 2020-07-03 | 华东师范大学 | Unmanned aerial vehicle anticollision early warning signal processing system based on FMCW millimeter wave radar |
-
2017
- 2017-10-31 CN CN201711045385.3A patent/CN107678030A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111366929A (en) * | 2020-03-06 | 2020-07-03 | 华东师范大学 | Unmanned aerial vehicle anticollision early warning signal processing system based on FMCW millimeter wave radar |
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Application publication date: 20180209 |