CN104157146B - Automobile running speed calculation method based on ultrahigh frequency radio frequency identification - Google Patents
Automobile running speed calculation method based on ultrahigh frequency radio frequency identification Download PDFInfo
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- CN104157146B CN104157146B CN201410335119.4A CN201410335119A CN104157146B CN 104157146 B CN104157146 B CN 104157146B CN 201410335119 A CN201410335119 A CN 201410335119A CN 104157146 B CN104157146 B CN 104157146B
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Abstract
The invention relates to an automobile running speed calculation method based on ultrahigh frequency radio frequency identification, which comprises the following steps: a. a directional antenna is arranged right above a road, and the directional antenna and an automobile electronic tag reader can receive and transmit radio frequency signals with an automobile electronic tag on an automobile in the effective coverage area of the directional antenna; b. the method comprises the following steps that an automobile electronic tag reader captures a plurality of radio frequency echo signals of an automobile electronic tag on the same automobile through a directional antenna at different moments, the automobile electronic tag reader obtains the reading position of the automobile electronic tag according to the captured radio frequency echo signals, and the instantaneous driving speed of the automobile is obtained through calculation; c. and the automobile electronic tag reader calculates the driving speed of the automobile according to the calculated instantaneous driving speed. The invention can realize the supervision of the traffic running state of vehicles running on the road, and has simple and convenient calculation method, high precision and strong environmental adaptability.
Description
Technical field
The present invention relates to the computation processing method of a kind of automobile driving speed, especially one penetrate based on hyperfrequency
The automobile driving speed computational methods that frequency identifies, belong to the technical field of traffic administration.
Background technology
Since entering 21 century, along with developing rapidly and the propelling of Urbanization Construction paces of China's economy, north
Resident's car owning amount of numerous big and medium-sized cities such as capital, Guangzhou, Nanjing, Xi'an has reached 20/one hundred houses, I
State is just accelerating into automotive society.But the automobile civilization driving behavior of the public and Social Responsibility Sense do not have
Have and obtain synchronizing to improve, overspeed seriously, random lane change and do not observe the uncivil behavior of driving such as traffic signal
Phenomenon is more universal, causes urban traffic blocking day by day serious, and road traffic accident takes place frequently.Therefore, for adding
The management of rope-race road order, be sure of road safety, unimpeded, and various places public safety traffic management department compels to be essential and obtains in real time
Take urban road and vehicle on expressway driving information, strengthen the friendship to overspeed seriously, arbitrarily change vehicle
The investigation of logical infringement.
Ultrahigh frequency radio frequency identification technology (UHF RFID) be a kind of utilize that radio communication mode realizes non-
Contact automatic identification technology.This technology is acknowledged as one of 21 century major application technology, can extensively apply
In fields such as public safety, traffic administration, logistics management and the manufacturings, it it is future city transport information
The important directions built.At present, the development of passive ultra-high frequency RFID technology is more ripe, Brazil, newly adds
The cities such as the country such as slope, Mexico and China Chongqing, Nanjing are progressively the most universal in terms of vehicle pass-through supervision
Application.
In daily traffic administration, the differentiation of automobile driving speed is mainly adopted by various places public safety traffic management department
With radar microwave speed-measuring method, ground buried coil sensing speed-measuring method and video image technology speed-measuring method etc..Its
In: radar microwave speed-measuring method is mainly used in police's mobile law enforcement, and ground buried coil senses speed-measuring method and regards
Frequently image technique speed-measuring method is mainly used in fixed law enforcement of testing the speed.These technology major defect in the application
It is can not effectively to identify false-trademark fake license plate vehicle, and is affected bigger by the environmental factors such as weather and lighting condition.
Identify the automotive electronics label of technology based on UHF RFID, the echo-signal that can use electronic tag is strong
Degree (RSSI) realizes distinguishing determination of distance and the reckoning of speed.The basic rule of any radio signal propagation
Rule is: the signal intensity of receiving terminal capture is the strongest, illustrates that transmitting terminal is the nearest with the distance of receiving terminal；Otherwise,
The signal intensity of receiving terminal capture is the most weak, illustrates that transmitting terminal is the most remote with the distance of receiving terminal.Therefore, it can root
According to the distance between the measure of the change sending and receiving end of wireless signal strength.
Summary of the invention
It is an object of the invention to overcome the deficiencies in the prior art, it is provided that a kind of based on super high frequency radio frequency knowledge
Other automobile driving speed computational methods, it can realize the traffic circulation state supervision of driving vehicle on road,
Computational methods are easy, and precision is high, and environmental suitability is strong.
The technical scheme provided according to the present invention, a kind of automobile driving speed meter based on super high frequency radio frequency identification
Calculation method, described automobile driving speed computational methods comprise the steps:
A, at the beam antenna that is arranged above of road, described beam antenna and automotive electronics label reader,
Described automotive electronics label reader can be with the automotive electronics mark on automobile in the effective overlay area of beam antenna
Sign the transmitting-receiving carrying out radiofrequency signal；
B, automotive electronics label reader are got on the car electronics capturing same automobile by beam antenna the most in the same time
Multiple rf echo signals of label, automotive electronics label reader obtains according to the rf echo signal of capture
The recognition position of automotive electronics label, according to the position of adjacent twice recognition, time interval, beam antenna with
The difference in height of automotive electronics label, is calculated the instantaneous travel speed of automobile；
C, automotive electronics label reader obtain the traveling of automobile according to the instantaneous traveling speed calculation of above-mentioned calculating
Speed.
Beam antenna and automotive electronics label reader are arranged on road by portal frame or L-type cantilever shalving
Side.
The capture of described automotive electronics label reader receives the information bag of the rf echo signal of automotive electronics label
Include echo signal intensity and information of vehicles that described automotive electronics label is identified.
Described automotive electronics label is arranged on automobile, the signal packet bracket of the identified vehicle of automotive electronics label
Trade mark code, type of vehicle or inspection expiration date.
Described automotive electronics label reader is by carrying out radiofrequency signal between beam antenna and automotive electronics label
The operating frequency of transmitting-receiving is 860MHz～960MHz.
Described automotive electronics label reader 13 obtains automotive electronics label position according to the rf echo signal of capture
The method put is:
Wherein, L is recognition positional distance (m)；RSSI is that automotive electronics label reader receives automotive electronics mark
The echo signal intensity (dBm) signed；A is that automotive electronics tag distances automotive electronics label reader is at 1m
The echo signal intensity (dBm) at place；α is the power attenuation factor；h0For beam antenna setting height(from bottom) and automobile
The setting height(from bottom) of electronic tag is poor (m).
Described automotive electronics label reader obtains automobile driving speed by weighted average or curve matching.
Described automotive electronics label reader and one to four beam antenna connect.
Compared with current art, technical characterstic and advantage that the present invention applies in field of traffic control are:
1, case be applicable to round-the-clock 24 hours road traffic supervision, testing vehicle register recognition accuracy rate 99% with
On, overcome current number plate video image identification technology the highest because of weather and the best recognition rate caused of lighting condition
Etc. problem；
2, being automotive electronics label low cost, life-span length and high false proof tamper performance thereof, arrangement for reading props up
Hold multiple target quickly to distinguish, can effectively identify false-trademark deck problem.
3, it is that automotive electronics label is read for the video image identification technology of current band floor light
Read device and can not want the lighting requirement of auxiliary light, therefore, there is the performance of energy-conserving and environment-protective, also reduce meanwhile
Night, the visual field of driver was disturbed by high light, improve traffic safety.
Accompanying drawing explanation
Fig. 1 is the structural representation that present invention automobile driving speed based on ultrahigh radio frequency identification calculates.
Fig. 2 is the flow chart of the present invention.
Detailed description of the invention
Below in conjunction with concrete drawings and Examples, the invention will be further described.
As depicted in figs. 1 and 2: in order to be able to realize the traffic circulation state supervision of driving vehicle on road,
Realize the easy accurate of automobile driving speed is calculated, automobile driving speed computational methods of the present invention include as
Lower step:
A, at the beam antenna that is arranged above of road, described beam antenna and automotive electronics label reader 13,
Described automotive electronics label reader 13 can be with the automobile on automobile 15 in the effective overlay area of beam antenna
Electronic tag 16 carries out the transmitting-receiving of radiofrequency signal；
Beam antenna and automotive electronics label reader 13 are arranged on by portal frame 11 or L-type cantilever shalving
Above road.Described automotive electronics label reader 13 is connected with one to four beam antenna.Shown in Fig. 1
The schematic diagram of two beam antennas is set on portal frame 11, two beam antennas include beam antenna 12 with
And beam antenna 14, beam antenna 12 and beam antenna 14 lay respectively at the surface in corresponding track, vapour
Car electronic tag 16 is arranged on the relevant position of automobile 15, and automotive electronics label 16 can store automobile 15
Essential information, described essential information includes vehicle license plate number, type of vehicle and inspection expiration date etc..
In the embodiment of the present invention, usually, automotive electronics label reader 13 includes that ultra-high frequency module (sends
Device and receptor), the composition such as CPU control unit and antenna (internal or external).Automotive electronics label 16
It is made up of chip, antenna and coupling element.Each automotive electronics label 16 has unique electronic code.
Automotive electronics label reader 13, automotive electronics label 16 all can use the structure that the art is conventional,
The automotive electronics label 16 installation site on automobile 15 can use the position that the art is conventional, for
Known to those skilled in the art, here is omitted.
B, automotive electronics label reader 13 are capturing vapour on same automobile 15 the most in the same time by beam antenna
Multiple rf echo signals of car electronic tag 16, automotive electronics label reader 13 is according to the radio frequency of capture
Echo-signal obtains the recognition position of automotive electronics label 16, according to the position of adjacent twice recognition, between the time
Every the difference in height of, beam antenna with automotive electronics label 16, it is calculated the instantaneous travel speed of automobile 15；
Specifically, effectively covering of beam antenna is entered when the automobile 15 being provided with automotive electronics label 16 travels
In cover region territory, automotive electronics label reader 13 can repeatedly obtain described automotive electronics label 16 echo-signal
The information of vehicles that intensity and automotive electronics label 16 are identified；According to information of vehicles, echo signal intensity value
With recognition distance correspondence mathematical model, extrapolate described automotive electronics label 16 and be connected automotive electronics mark
Sign the distance between the beam antenna of reader 13；According to every time obtain the time interval of echo-signal, described
The change in location of automobile 15, beam antenna setting height(from bottom) are poor with automotive electronics label 16 setting height(from bottom), calculate
Go out automobile transient motion speed (note: owing to each time interval is Millisecond, therefore, it can each time
The speed of each time interval is considered as transient motion speed；Automotive electronics label reader 13 is the most accurately
Recognition is typically remote at 30 meters to the position of the echo-signal of automotive electronics label 16).
In the embodiment of the present invention, automotive electronics label reader 13 is in order to obtain automotive electronics label 16
Recognition position, need corresponding relational model is set in advance in automotive electronics label reader 13, specifically
For:
Step 21: by test and experiment, it is thus achieved that the automotive electronics label 16 echo letter in different vehicle type
Number intensity level, and according to testing data in a large number, sets up and is suitable for described automotive electronics label reader 16 and fixed
To the echo signal intensity value of antenna and recognition distance correspondence mathematical model, described corresponding relation is:
Wherein, L is recognition positional distance (m)；RSSI be automotive electronics label reader connect 13 receive automobile electricity
The echo signal intensity (dBm) of subtab 16；A is that automotive electronics label 16 is read apart from automotive electronics label
Read the device 13 echo signal intensity (dBm) at 1m, be the constant of an actual measurement；α be power attenuation because of
Son, is the constant of an actual measurement；h0Setting height(from bottom) for beam antenna setting height(from bottom) Yu automotive electronics label 16
Difference (m).
Step 22: by the echo signal intensity value of above-mentioned foundation and recognition distance correspondence mathematical model, determine
The parameters such as the difference in height to antenna and automotive electronics label 16 input described automotive electronics label reader 13, and
Automobile position and travel speed to described automotive electronics label reader 13 calculate and detect and demarcate, warp
Test index of correlation, in specifying deviation range, can be used for speed and differentiate.
Step 23: automotive electronics label reader 13 and beam antenna are arranged on the portal frame of test road
On 11.Automotive electronics label reader 13 is continuously sent out over request-reply information by beam antenna, and repeatedly
Capture enters beam antenna and effectively distinguishes echo signal intensity value and the car that the automotive electronics label 16 in region spreads out of
Information, according to the corresponding pass in automotive electronics label reader 13, calculates the current distance of automobile 15
Positional information is (corresponding to horizontal level L1、L2、……、Ln-1、Ln)。
L1Enter behind the effective overlay area of beam antenna, by orienting for being provided with the automobile of automotive electronics label 16
To the position of automotive electronics label 16, (the recognition time is T in antenna 12 for the first time recognition1Moment)；L2It is fixed
To antenna 12 at T2To the position of automotive electronics label 16, (the recognition time is T in moment second time recognition2Moment)；
By that analogy, Ln-1The position of automotive electronics label 16 is arrived (during recognition for 12 (n-1)th recognition of beam antenna
Between be Tn-1Moment)；LnPosition (the recognition of automotive electronics label 16 is distinguished for beam antenna 12 n-th
Time is TnMoment).
Step 24: in the effective overlay area of beam antenna, automotive electronics label reader 13 is the most in the same time
The same automobile 15 that success captures is got on the car multiple echo-signals of electronic tag 16, according to adjacent twice knowledge
The difference in height of change in location, time interval, beam antenna setting height(from bottom) and the automotive electronics label 16 read, will
After distance between beam antenna and automobile 15 is converted to horizontal range, extrapolate the automobile instantaneous row of each period
Sail speed, it may be assumed that
V12=(L2-L1)/(T2-T1)；
……；
Vn-1n=(Ln-Ln-1)/(Tn-Tn-1)。
In the embodiment of the present invention, the capture of described automotive electronics label reader 13 receives automotive electronics label 16
The information of rf echo signal include the car that echo signal intensity and described automotive electronics label 16 are identified
Information.Described automotive electronics label 16 is arranged on automobile 15, the identified vehicle of automotive electronics label 16
Signal packet include brand number, type of vehicle or inspection expiration date.Described automotive electronics label reader 13
By the operating frequency carrying out radiofrequency signal transmitting-receiving between beam antenna and automotive electronics label 16 it is
860MHz～960MHz.
C, automotive electronics label reader 13 obtain automobile 15 according to the instantaneous traveling speed calculation of above-mentioned calculating
Travel speed.
Step 25: calculate after the comprehensively instantaneous travel speed of the automobile of each period, weighted average or curve matching
Draw automobile driving speed value V, such as V=(V12+V23+…+Vn-1n)/(n-1).Certainly, specifically
During enforcement, automotive electronics label reader 13 also uses other mode to obtain vapour according to instantaneous travel speed
The travel speed of car 15.
In the embodiment of the present invention, other of the travel speed of automobile 15 and automotive electronics label reader 13 is defeated
Output (such as hour traffic flow etc.) is using the traffic real time status information as road section, for traffic pipe
Reason department judges the important indicator whether road traffic blocks up, and can act also as the foundation of public security traffic law enforcement or public
The reference frame of many trip navigation Service.
Compared with current art, technical characterstic and advantage that the present invention applies in field of traffic control are:
One, case be applicable to round-the-clock 24 hours road traffic supervision, testing vehicle register recognition accuracy rate 99% with
On, overcome current number plate video image identification technology the highest because of weather and the best recognition rate caused of lighting condition
Etc. problem；
Two, being automotive electronics label 16 low cost, life-span length and high false proof tamper performance thereof, reading sets
Standby support multiple target is quickly distinguished, and can effectively identify false-trademark deck problem.
Three, it is for the video image identification technology of current band floor light, automotive electronics label
Reader 13 can not want the lighting requirement of auxiliary light, therefore, has the performance of energy-conserving and environment-protective, meanwhile, also
Decrease high light at night the visual field of driver is disturbed, improve traffic safety.
It should be noted that, the above is only embodiments of the present invention, and those skilled in the art should manage
Solve, under the premise without departing from the principles of the invention, some improvement can be carried out or equivalence is replaced, but these improve
Also should be regarded as protection scope of the present invention.
Claims (6)
1. automobile driving speed computational methods based on super high frequency radio frequency identification, is characterized in that, described vapour
Car travels speed calculation method and comprises the steps:
(a), at the beam antenna that is arranged above of road, described beam antenna is read with automotive electronics label
Device (13), described automotive electronics label reader (13) can be with automobile in the effective overlay area of beam antenna
(15) the automotive electronics label (16) on carries out the transmitting-receiving of radiofrequency signal；
B (), automotive electronics label reader (13) are capturing same automobile by beam antenna the most in the same time
(15) get on the car multiple rf echo signals of electronic tag (16), automotive electronics label reader (13)
Rf echo signal according to capture obtains the recognition position of automotive electronics label (16), according to adjacent twice
The position of recognition, time interval, beam antenna and the difference in height of automotive electronics label (16), be calculated
The instantaneous travel speed of automobile (15)；
C (), automotive electronics label reader (13) obtain according to the instantaneous traveling speed calculation of above-mentioned calculating
The travel speed of automobile (15)；
The capture of described automotive electronics label reader (13) receives the radio-frequency echo wave of automotive electronics label (16)
The information of signal includes the information of vehicles that echo signal intensity and described automotive electronics label (16) are identified；
Described automotive electronics label reader (13) obtains automotive electronics mark according to the rf echo signal of capture
The method signing (16) position is:
Wherein, L is recognition positional distance, and unit is m；RSSI is automotive electronics label reader (13)
Receiving the echo signal intensity of automotive electronics label (16), unit is dBm；A is automotive electronics label
(16) distance automotive electronics label reader (13) echo signal intensity at 1m, unit is dBm；
α is the power attenuation factor；h0Setting height(from bottom) for beam antenna setting height(from bottom) Yu automotive electronics label (16) is poor,
Unit is m.
Automobile driving speed computational methods based on super high frequency radio frequency identification the most according to claim 1,
It is characterized in that: beam antenna and automotive electronics label reader (13) are by portal frame (11) or L-type
Cantilever shalving is arranged on above road.
Automobile driving speed computational methods based on super high frequency radio frequency identification the most according to claim 1,
It is characterized in that: described automotive electronics label (16) is arranged on automobile (15), automotive electronics label (16)
The signal packet of institute's mark vehicle includes brand number, type of vehicle or inspection expiration date.
Automobile driving speed computational methods based on super high frequency radio frequency identification the most according to claim 1,
It is characterized in that: described automotive electronics label reader (13) is by beam antenna and automotive electronics label (16)
Between to carry out the operating frequency of radiofrequency signal transmitting-receiving be 860MHz～960MHz.
Automobile driving speed computational methods based on super high frequency radio frequency identification the most according to claim 1,
It is characterized in that: described automotive electronics label reader (13) obtains automobile by weighted average or curve matching
Travel speed.
Automobile driving speed computational methods based on super high frequency radio frequency identification the most according to claim 1,
It is characterized in that: described automotive electronics label reader (13) is connected with one to four beam antenna.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410335119.4A CN104157146B (en) | 2014-07-14 | Automobile running speed calculation method based on ultrahigh frequency radio frequency identification |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410335119.4A CN104157146B (en) | 2014-07-14 | Automobile running speed calculation method based on ultrahigh frequency radio frequency identification |
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| Publication Number | Publication Date |
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| CN104157146A CN104157146A (en) | 2014-11-19 |
| CN104157146B true CN104157146B (en) | 2017-01-04 |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1862619A (en) * | 2005-05-13 | 2006-11-15 | 中兴通讯股份有限公司 | System and method for automatically monitoring vehicle overspeed, based on RF identifying technology |
| CN203520632U (en) * | 2013-07-31 | 2014-04-02 | 陈昊 | Traffic investigation and interval velocity measurement device based on ultrahigh radio frequency identification (RFID) technology |
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1862619A (en) * | 2005-05-13 | 2006-11-15 | 中兴通讯股份有限公司 | System and method for automatically monitoring vehicle overspeed, based on RF identifying technology |
| CN203520632U (en) * | 2013-07-31 | 2014-04-02 | 陈昊 | Traffic investigation and interval velocity measurement device based on ultrahigh radio frequency identification (RFID) technology |
Non-Patent Citations (1)
| Title |
|---|
| UHF频段RFID系统中运动物体方向与速度是别的研究;徐进;《中国优秀硕士学位论文全文数据库 信息科技辑》;20130415(第04期);第I138-1038页：正文第20-23页 * |
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