CN109493637A - A kind of parking space state detection method - Google Patents
A kind of parking space state detection method Download PDFInfo
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- CN109493637A CN109493637A CN201811605438.7A CN201811605438A CN109493637A CN 109493637 A CN109493637 A CN 109493637A CN 201811605438 A CN201811605438 A CN 201811605438A CN 109493637 A CN109493637 A CN 109493637A
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- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G1/00—Traffic control systems for road vehicles
- G08G1/14—Traffic control systems for road vehicles indicating individual free spaces in parking areas
- G08G1/145—Traffic control systems for road vehicles indicating individual free spaces in parking areas where the indication depends on the parking areas
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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
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/04—Systems determining presence of a target
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- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention discloses a kind of parking space state detection methods, including the microwave radar module being mounted on parking stall, the microwave radar module is at work in a manner of FMCW, emit pulsed FM signal, after the transmitting signal Tx of microwave radar module is emitted by transmitting antenna, it is received by receiving antenna, the reception signal of receiving antenna and local oscillation signal or transmitting signal are subjected to Frequency mixing processing, it obtains processing and receives signal, calculation processing receives the amplitude A of signal and the phase difference of processing reception signal, set angle decision thresholdWith amplitude decision threshold τ, when the phase difference is greater than or equal toThen indicate that there are an obvious obstructing objects above parking stall；When the phase difference is less thanAnd amplitude A is less than τ, then it represents that an obvious obstructing objects are not present above parking stall.Low energy consumption relative to conventional radar detection technique by the present invention, is not interfered by weather conditions and sundries, judges accuracy height.
Description
Technical field
The invention belongs to detections of radar field, being related to a kind of vehicle, there are detection techniques, and in particular to a kind of parking space state
Detection method.
Background technique
In the prior art, the vehicle-state on public parking stall generally uses geomagnetic sensors detection, and geomagnetic sensor has
Feature low in energy consumption, but its detection accuracy is not high is easy to be interfered by sundries, while the prior art exists and senses earth magnetism
The technology that device is combined with radar, but the technology is immature, in the application, is primarily present following problems or deficiency:
(1) 105242263 A of CN, patent " a kind of vehicle there are detection device and methods ", two of use are in certain angle
The doppler radar module of installation is spent, come the motion process for detecting the entrance of vehicle and using.Doppler radar can only detect edge
Radar radially there is the object of displacement movement, basically, this Doppler radar is only used for checking vehicle above parking stall
Motion state, be difficult differentiate parking stall static state working condition；Meanwhile vehicle, when entering and exiting parking stall, usual speed is very
It is low, and surface-based Doppler radar is limited by installation volume and ground level, vehicle is along radar cross section radial direction
Speed can be lower, to detect the vehicle movement of so low velocity, for wanting for Radar Signal Processing complexity and frequency resolution
Asking can be very high, and cost and power consumption are all big problems
(2) a kind of 201510991118.X, patent " microwave vehicle detection device and method based on earth magnetism guidance ", utilizes
The joint-detection of microwave and earth magnetism come realize parking space state detect, microwave detection method rely solely on detection echo signal
Amplitude, when amplitude is greater than or equal to some setting thresholding, then it is assumed that there are vehicle parkings on parking stall.This mode completely according to
Rely the amplitude information in echo, when there is sleet or detector upper surface there are in the case of the impurity such as sandy soil, leaf, completely
Just lose the ability of correct decision.
(3) 201710587627.5, patent " a kind of detection device of parking space state and the detection method of parking space state ", root
According to the difference of echo data Basic wave data corresponding with parking stall, if more than or equal to some setting variation threshold values,
To differentiate parking space state.Basic wave data include no vehicle state Basic wave data and parking state Basic wave data.It is this to sentence
Other mode excessively relies on the accuracy of benchmark state echo data, needs the acquisition of frequent progress benchmark state data, a secondary standard
Data acquire mistake, will cause the complete mistake of succeeding state differentiation, and robustness is very poor.
Summary of the invention
The object of the present invention is to provide a kind of parking space state detection methods, solve vehicle-state detection accuracy in the prior art
It is not high, it is easy the problem of being interfered.It is another object of the present invention to solve to carry out vehicle using radar sensor in the prior art
The problem that state-detection precision is not high and energy consumption is high.
In order to solve the above-mentioned technical problem, the technical solution adopted by the present invention is that:
A kind of parking space state detection method, including the microwave radar module being mounted on parking stall, it is characterised in that: described micro-
Wave radar module in a manner of FMCW, emits pulsed FM signal at work, and the transmitting signal Tx of microwave radar module passes through
It after transmitting antenna transmitting, is received by receiving antenna, by the reception signal of receiving antenna and local oscillation signal or transmitting signal
Frequency mixing processing is carried out, processing is obtained and receives signal, frequency sweep is calculated and handles the amplitude A for receiving signal and processing reception letter in the process
Number phase difference, set an angle decision thresholdWith amplitude decision threshold τ, when the phase difference is sentenced more than or equal to angle
Certainly thresholdingThen indicate that there are an obvious obstructing objects above parking stall；When the phase difference is less than angle decision thresholdAnd width
It spends A and is less than amplitude decision threshold τ, then it represents that an obvious obstructing objects are not present above parking stall.
Preferably, the angle change that the phase difference that the processing receives signal takes frequency sweep to handle reception signal in the process is accumulative
Value θ.
Preferably, the specific acquisition methods of processing phase of received signal difference are as follows:
Step 1, the initial frequency f for determining microwave radar module0, swept bandwidth B and frequency sweep duration T；
Step 2, microwave radar module send discrete FM signal, i.e. moment t by the way of pulse0Send frequencyModulated signal；
The radio frequency reception end acquisition of step 3, microwave radar module receives signal；
Step 4 will receive signal and local oscillation signal or transmitting signal progress Frequency mixing processing, obtain processing and receive signal；
Step 5 repeats step 1 to step 4, until completing the frequency sweep of whole bandwidth Bs, the processing for obtaining n sampled point is connect
The collection of letters number, calculates the processing phase of received signal variation difference of neighbouring sample point, and all phase change differences are added up phase
Add, obtains angle change aggregate-value θ.
Preferably, the processing receives signal after Frequency mixing processing, and calculating phase difference, the specific method is as follows:
Step a, the reception signal after Frequency mixing processing is filtered by low-pass filter；
Step b, the reception signal after low-pass filter filters out high fdrequency component by smothing filtering, and modulation /demodulation obtains
Processing to two-way orthogonal signalling receives signal, and the road I signal and the road Q signal, calculate the road I signal mean value respectivelyThe road Q letter
Number mean valueAnd range signal mean value
Step c, it is handled according to reception signal of the step a to step c method to all sampled points, obtains processing and receive
Signal set；
Step d, to sampled pointIt carries out curve fitting, n is indicated during frequency sweep
Emit the number of FM signal；
Step e, matched curve section is calculated, rotates angle, θ from the largest cumulative of origin-to-destination.
Preferably, to sampled pointRange signal take mean value computation, obtain everywhere
Reason receives the amplitude A of signal.
Preferably, the initial frequency f0Range is 22-25GHz wave band, and swept bandwidth B range is 300-500MHz, is swept
Frequency duration T range is 10-400us.
It preferably, further include geomagnetic sensor, the geomagnetic sensor long term monitoring, microwave radar module is intermittent work
Make state, when geomagnetic sensor monitors changes of magnetic field, just starts microwave radar module and detected according to above-mentioned sweep method.
The medicine have the advantages that
The present invention utilizes discrete FMCW frequency-modulated wave, the scanning to short-time pulse formula is carried out above parking stall, by from receiving end
Discrete sampling point is extracted, and calculates the angle between sampling point and amplitude information, to differentiate within the scope of certain height, is above parking stall
It is no to there is reflection object.This kind of mode, different from relying solely on amplitude information, the i.e. discriminant approach of echo strength, it is fixed not need
The calibration of phase, do not need record parking stall above areflexia object when reference waveform, not by temperature and radio-frequency front-end aging etc. because
The influence of element will not cause to differentiate the irrecoverable of mistake because of the calibration of primary mistake.Meanwhile it not using traditional continuous
FMCW frequency sweep and the mode of FFT time-frequency domain conversation carry out signal processing, greatly reduce the complexity and power consumption of realization.
Detailed description of the invention
Fig. 1 is the present invention using microwave radar module progress parking space state detection structure schematic diagram.
Fig. 2 is microwave radar module in the embodiment of the present invention according to FMCW frequency-modulated wave frequency sweep schematic diagram.
Specific embodiment
A kind of parking space state detection method of the present invention, including the microwave radar module being mounted on parking stall, the microwave thunder
Up to module at work in a manner of FMCW, transmit cycle is the pulsed FM signal of T, the transmitting signal of microwave radar module
After Tx is emitted by transmitting antenna, a part encounters barrier and reflects, and is received antenna reception, the reflected received signal
It is denoted as Rx1, it is assumed that emitting signal isWherein A1Indicate the amplitude of transmitting FM signal, f0Table
Show that frequency modulation original frequency, B indicate that modulating bandwidth, T indicate frequency modulation wave duration, the received reflection signal Rx of receiving antenna1ForWherein A3Indicate the amplitude of reflection signal,C is the light velocity, and D indicates anti-
The distance between object and receiving antenna are penetrated, d indicates the distance between transmitting antenna and receiving antenna；Another part is simultaneously
Leakage signal Rx2Directly it is received antenna reception, leakage signal Rx2ForWherein A2It indicates
The amplitude of leakage signal, θ indicate phase deviation, and phase deviation is mainly due to the distance between transmitting antenna and receiving antenna d
Caused, distance d is constant, is steady state value, and the received actual signal Rx of receiving antenna is reflected received signal Rx1Believe with leakage
Number Rx2Superposition, therefore the received actual signal Rx of receiving antenna are as follows:
And local oscillation signal actual signal Rx is demodulated by chip interior modem, i.e.,
It is handled to obtain:
Above-mentioned formula is unfolded to obtain processing reception signal are as follows:
After above formula carries out conversion process, reject high fdrequency component, can approximate abbreviation at:
Wherein α, φ are and D and t1Unrelated constant, β are variable relevant to D, and δ is that adjacent processing twice receives signal
Phase difference.
From the above equation, we can see that i.e. D is fixed for the barrier of a certain determination, phase difference δ is one with time t1Variation
The speed of trigonometric function, angle change is influenced by B and D, and swept bandwidth B is bigger, and the changing value for adding up angle is bigger, obstacle
Object distance D is bigger, and the changing value for adding up angle is also bigger.
According to above-mentioned characteristic, the present invention designs one kind not only by echo strength, does not need record Basic wave, is not required to
Want the mode of frequent calibration, so that it may be accurately judged to the method that whether there are obstacles on parking stall.Processing of the present invention
Method and key step are as follows:
(1) an initial frequency f is determined0=23.75GHz, swept bandwidth B=400MHz and frequency sweep duration T=300us；
And angle decision threshold T and amplitude decision threshold τ；
(2) microwave radar module is by the way of pulse, controls radio frequency transmitting line, send discrete frequency increments or
The FM signal that frequency is successively decreased, i.e. moment t0Send frequencyModulated signal；
(3) it is acquired at radio frequency reception end and receives signal；
(4) signal and local oscillation signal will be received or transmitting signal carries out Frequency mixing processing, and handled by low-pass filter；
(5) high fdrequency component is filtered out by smothing filtering, and records the obtained road I signal mean value after processingThe road Q signal
Mean valueAnd range signal mean valueThe two-way that the road I signal and the road Q signal are the mode of orthogonal modulation and demodulation to handle
Signal will receive signal and carry out 90 degree of phase shift all the way, all the way without phase shift, obtains orthogonal two paths of signals；
(6) step (2)~(5) are repeated, until completing the frequency sweep of whole bandwidth Bs
(7) to sampled pointIt carries out curve fitting
(8) matched curve section is calculated, the angle change aggregate-value θ of signal is received from origin-to-destination processing；
(9) to sampled pointAmplitude carry out taking mean value computation, be recorded as A；
(10) judging process: when angle change aggregate-value θ is greater than or equal to angle decision thresholdIt then indicates above parking stall
There are an obvious obstructing objects；When angle change aggregate-value θ is less than angle decision thresholdAnd amplitude A is adjudicated less than amplitude
Thresholding τ, then it represents that an obvious obstructing objects are not present above parking stall, when angle change aggregate-value θ is less than angle decision thresholdAmplitude A is greater than or equal to amplitude decision threshold τ, then it represents that there are impurity interference above parking stall, combine geomagnetic sensor at this time
Judge that parking stall is whether to exclude the impurity interference in the case of this kind by geomagnetic sensor there are vehicle.
In certain the above embodiment of the present invention, after frequency sweep process, processing receives the angle change of signal
Aggregate-value θ is as judgment criteria, naturally it is also possible to receive the angle change value δ of signal as judgement using adjacent processing twice
Standard, at this time angle decision thresholdModify small, but due in actual application, adjacent processing twice receives signal
Phase difference it is smaller, difficult judgment, therefore general the angle change aggregate-value θ of signal is received as judgment criteria using processing.
It should be noted that microwave radar module certainly may be used using 24GHz wave band as working frequency range in the present embodiment
To use other working frequency range.
It is to be noted that in the embodiment of the present invention, the road I signal mean valueWith the road Q signal mean valueIt is real for signal strength
Border uses the level magnitudes of sampled point signal, naturally it is also possible to be scaled power.
It should be noted that the amplitude of local oscillation signal does not have any shadow for the embodiment of the present invention in the embodiment of the present invention
It rings, is a constant constant during change process.
Claims (7)
1. a kind of parking space state detection method, including the microwave radar module being mounted on parking stall, it is characterised in that: the microwave
Radar module in a manner of FMCW, emits pulsed FM signal at work, and the transmitting signal Tx of microwave radar module passes through hair
After penetrating antenna transmitting, received by receiving antenna, by the reception signal of receiving antenna and local oscillation signal or transmitting signal into
Row Frequency mixing processing obtains processing and receives signal, and processing, which receives the amplitude A of signal and handles, during calculating frequency sweep receives signal
Phase difference sets an angle decision thresholdWith amplitude decision threshold τ, when the phase difference be greater than or equal to angle decision thresholdThen indicate that there are an obvious obstructing objects above parking stall；When the phase difference is less than angle decision thresholdAnd amplitude A is less than
Amplitude decision threshold τ, then it represents that an obvious obstructing objects are not present above parking stall.
2. parking space state detection method as described in claim 1, it is characterised in that: the phase difference that the processing receives signal takes
The angle change aggregate-value θ for receiving signal is handled during frequency sweep.
3. parking space state detection method as claimed in claim 2, it is characterised in that: the processing phase of received signal difference is specific
Acquisition methods are as follows:
Step 1, the initial frequency f for determining microwave radar module0, swept bandwidth B and frequency sweep duration T；
Step 2, microwave radar module send discrete FM signal, i.e. moment t by the way of pulse0Send frequencyModulated signal；
The radio frequency reception end acquisition of step 3, microwave radar module receives signal；
Step 4 will receive signal and local oscillation signal or transmitting signal progress Frequency mixing processing, obtain processing and receive signal；
Step 5 repeats step 1 to step 4, until completing the frequency sweep of whole bandwidth Bs, the processing for obtaining n sampled point receives letter
Number, the processing phase of received signal variation difference of neighbouring sample point is calculated, and by the accumulative addition of all phase change differences, obtain
Angle change aggregate-value θ.
4. parking space state detection method as claimed in claim 3, it is characterised in that: the processing receives signal by mixing
After reason, calculating phase difference, the specific method is as follows:
Step a, the reception signal after Frequency mixing processing is filtered by low-pass filter；
Step b, the reception signal after low-pass filter filters out high fdrequency component by smothing filtering, and modulation /demodulation obtains two
The processing of road orthogonal signalling receives signal, and the road I signal and the road Q signal, calculate the road I signal mean value respectivelyThe road Q signal mean valueAnd range signal mean value
Step c, it is handled according to reception signal of the step a to step c method to all sampled points, obtains processing and receive signal
Set；
Step d, to sampled pointIt carries out curve fitting, n indicates to emit during frequency sweep
The number of FM signal；
Step e, matched curve section is calculated, rotates angle, θ from the largest cumulative of origin-to-destination.
5. parking space state detection method as claimed in claim 4, it is characterised in that: to sampled point Range signal take mean value computation, obtain processing receive signal amplitude A.
6. the parking space state detection method as described in claim 3 to 5 any one, it is characterised in that: the initial frequency f0Model
Enclosing is 22-25GHz wave band, and swept bandwidth B range is 300-500MHz, and frequency sweep duration T range is 10-400us.
7. the parking space state detection method as described in claim 1 to 5 any one, it is characterised in that: further include earth magnetism sensing
Device, the geomagnetic sensor long term monitoring, microwave radar module is service intermittent state, when geomagnetic sensor monitors magnetic field
When variation, just starts microwave radar module and detected according to above-mentioned sweep method.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110164180A (en) * | 2019-07-09 | 2019-08-23 | 深圳市华腾物联科技有限公司 | A kind of parking lot management method and apparatus based on earth magnetism |
| CN112505674A (en) * | 2020-12-17 | 2021-03-16 | 广东蓝水花智能电子有限公司 | Automatic door control method and system based on FMCW microwave inductor |
| CN114421146A (en) * | 2022-01-20 | 2022-04-29 | 深圳市道通智能汽车有限公司 | Radar and vehicle |
| CN117031415A (en) * | 2023-10-10 | 2023-11-10 | 深圳迈睿智能科技有限公司 | Microwave detector with fixed frequency conversion rule and anti-radiation interference method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105445734A (en) * | 2014-09-19 | 2016-03-30 | 德尔福技术有限公司 | Radar system with phase based multi-target detection |
| CN107402312A (en) * | 2016-05-18 | 2017-11-28 | 英飞凌科技股份有限公司 | The method and apparatus sensed for speed and/or position |
| CN108877291A (en) * | 2018-08-09 | 2018-11-23 | 杭州朗米科技有限公司 | A kind of geomagnetic parking stall detection system based on fmcw radar and vehicle-mounted card-reading device |
| CN109073743A (en) * | 2017-12-18 | 2018-12-21 | 深圳市大疆创新科技有限公司 | Weak target detection method, microwave radar sensor and unmanned plane |
-
2018
- 2018-12-26 CN CN201811605438.7A patent/CN109493637B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105445734A (en) * | 2014-09-19 | 2016-03-30 | 德尔福技术有限公司 | Radar system with phase based multi-target detection |
| CN107402312A (en) * | 2016-05-18 | 2017-11-28 | 英飞凌科技股份有限公司 | The method and apparatus sensed for speed and/or position |
| CN109073743A (en) * | 2017-12-18 | 2018-12-21 | 深圳市大疆创新科技有限公司 | Weak target detection method, microwave radar sensor and unmanned plane |
| CN108877291A (en) * | 2018-08-09 | 2018-11-23 | 杭州朗米科技有限公司 | A kind of geomagnetic parking stall detection system based on fmcw radar and vehicle-mounted card-reading device |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110164180A (en) * | 2019-07-09 | 2019-08-23 | 深圳市华腾物联科技有限公司 | A kind of parking lot management method and apparatus based on earth magnetism |
| CN112505674A (en) * | 2020-12-17 | 2021-03-16 | 广东蓝水花智能电子有限公司 | Automatic door control method and system based on FMCW microwave inductor |
| CN114421146A (en) * | 2022-01-20 | 2022-04-29 | 深圳市道通智能汽车有限公司 | Radar and vehicle |
| CN114421146B (en) * | 2022-01-20 | 2024-05-17 | 深圳市塞防科技有限公司 | Radar and vehicle |
| CN117031415A (en) * | 2023-10-10 | 2023-11-10 | 深圳迈睿智能科技有限公司 | Microwave detector with fixed frequency conversion rule and anti-radiation interference method thereof |
| CN117031415B (en) * | 2023-10-10 | 2024-01-16 | 深圳迈睿智能科技有限公司 | Microwave detector with fixed frequency conversion rule and anti-radiation interference method thereof |
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Denomination of invention: A Method for Detecting Parking Space Status Effective date of registration: 20230919 Granted publication date: 20211203 Pledgee: Wuhan Guanggu Branch of Hubei Bank Co.,Ltd. Pledgor: WUHAN TURBO TECHNOLOGIES Corp. Registration number: Y2023980057502 |