CN110956236A

CN110956236A - ETC portal roadside read-write method and reader-writer

Info

Publication number: CN110956236A
Application number: CN201911136048.4A
Authority: CN
Inventors: 陈碧军; 李卫锋; 余敏; 黄伟
Original assignee: Guangdong Chuangyu Electromechanical Engineering Co ltd
Current assignee: Guangdong Chuangyu Electromechanical Engineering Co ltd
Priority date: 2019-11-19
Filing date: 2019-11-19
Publication date: 2020-04-03

Abstract

The invention belongs to the technical field of intelligent transportation, and particularly relates to an ETC portal roadside read-write method and a reader-writer. The ETC portal roadside read-write method comprises the following steps: s101: when a vehicle passes through the ETC portal roadside, the loop sensor detects the vehicle, and the central management system controls the RSU to work and send a low-frequency modulation signal to the vehicle; s102: if the vehicle does not feed back the low-frequency modulation signal, the vehicle is not provided with the OBU, and the central management system controls the railing to be closed; s103: if the low-frequency modulation signals of the vehicles are fed back, the OBU is assembled on the vehicle, and the OBU on the vehicle feeds back the low-frequency modulation signals at the moment; s104: the central management system controls a license plate recognizer on the ETC portal roadside to shoot a license plate of the vehicle and transmits a shot picture to the license plate recognition system. The invention can intercept the vehicle with ETC, avoid the phenomenon of fee evasion with the vehicle, and simultaneously intercept the vehicle with the vehicle license plate not in conformity with the OBU data.

Description

ETC portal roadside read-write method and reader-writer

Technical Field

The invention relates to the technical field of intelligent traffic management, in particular to an ETC portal roadside read-write method and a reader-writer.

Background

RFID (radio Frequency identification) is radio Frequency identification. The method is a non-contact automatic identification technology, and automatically identifies a target object and acquires related data through a radio frequency signal.

ETC (Electronic Toll Collection ) is an advanced charging mode which is strongly worried by all countries in the world at present. The vehicle owner only needs to install the electronic tag on the vehicle window, when the vehicle passes through the toll station, the electronic tag passing through the vehicle is read and written and identified through the reader-writer arranged on the toll station, corresponding expenses are automatically deducted from a pre-bound radio frequency card or a bank account, the vehicle can quickly pass through the toll station without parking and manual payment of the vehicle owner, and one-way smoothness is really realized, wherein the ETC system mainly comprises a vehicle automatic identification system, a central management system and other auxiliary facilities. The automatic vehicle identification system is composed of an OBU (On board unit, i.e., an electronic tag), an RSU (Road side unit, i.e., a reader/writer), a loop sensor, and the like.

Compared with the traditional parking charging, the adoption of ETC has the following advantages:

(1) the traffic is smoother, a driver can directly and automatically pay fees through the ETC system without stopping the vehicle, the vehicle traffic capacity of the toll station is effectively improved, traffic jam caused by the toll station is avoided, and the highway utilization rate is improved;

(2) the payment is convenient and transparent, and the driver pays the fee through the ETC system, which means that the number of passing vehicles in unit time is more, so that the payment speed is accelerated, and the payment efficiency is improved;

(3) the ETC system reduces the waiting time of manual payment of the vehicle at the toll station, reduces oil consumption, and reduces tail gas emission when the vehicle idles, thereby achieving the effects of energy conservation and environmental protection.

However, the existing ETC system has the following disadvantages when in use:

the invention provides an ETC portal read-write method and a card reader, wherein the ETC portal read-write method comprises the following steps that a vehicle runs with a vehicle, the vehicle which is not provided with an ETC runs along with the vehicle which is provided with the ETC, so that the purpose of fee evasion is achieved, but when an existing ETC system is applied, only the vehicle which is provided with the ETC can be identified and charged, and the vehicle which is not provided with the ETC cannot be processed, so that the phenomenon is effectively solved, only monitoring videos can be consulted and compared with payment records of a payment system, whether the vehicle has the fee evasion phenomenon or not is judged, certain defects exist, and meanwhile, the phenomenon that an ETC card is embezzled exists in the ETC system, so that economic losses are brought to ETC users.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides an ETC portal roadside read-write method and a reader-writer, and aims to solve the problems in the background art.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme:

an ETC portal roadside read-write method comprises the following steps:

s101: when a vehicle passes through the ETC portal roadside, the loop sensor detects the vehicle, and the central management system controls the RSU to work and send a low-frequency modulation signal to the vehicle;

s102: if the vehicle does not feed back the low-frequency modulation signal, the vehicle is not provided with the OBU, and the central management system controls the railing to be closed;

s103: if the low-frequency modulation signals of the vehicles are fed back, the OBU is assembled on the vehicle, and the OBU on the vehicle feeds back the low-frequency modulation signals at the moment;

s104: the central management system controls a license plate recognizer on the roadside of the ETC portal frame to shoot a license plate of the vehicle and transmits a shot picture to the license plate recognition system;

s105: the license plate recognition system recognizes the license plate information and transmits the license plate information to the central management system;

s106: the OBU sends out an inquiry signal to the RSU beside the roadside of the ETC portal according to the received low-frequency modulation signal, and the RSU receives the inquiry signal of the OBU and transmits the inquiry signal of the OBU to the central management system;

s107: the central management system compares the information of the OBU with the license plate information and feeds back the information;

s108: if the information of the OBU is matched with the license plate information, the RSU receives the inquiry signal of the OBU and establishes bidirectional communication and data exchange, and the vehicle normally passes through a toll station to finish the vehicle fee deduction work;

s109: and if the information of the OBU does not accord with the license plate information, the RSU rejects the inquiry signal of the OBU and closes the railing.

As a preferred technical solution of the present invention, in step S101, the generation and sending processes of the low-frequency modulation signal are as follows:

(1) the RSU generates a low-frequency carrier signal;

(2) inputting a modulation command and modulation data, and modulating a low-frequency carrier signal into a low-frequency modulation signal comprising a request feedback instruction;

(3) and amplifying the low-frequency modulation signal, and transmitting the low-frequency modulation signal to the vehicle through a low-frequency magnetic field information channel.

As a preferred technical solution of the present invention, in step S104, the license plate information recognition step includes:

(1) the license plate recognizer tracks, positions and shoots the license plate of the vehicle;

(2) the license plate setting device transmits the shot license plate image to a license plate recognition system;

(3) the license plate recognition system recognizes the license plate image to generate recognized license plate data;

(4) the license plate recognition system carries out decision judgment on the license plate data;

(5) if the recognizable license plate data is recognized, the license plate data is transmitted to a central management system;

(6) if the license plate data which can not be identified is not identified, the license plate is tracked, positioned and shot again.

As a preferable technical scheme of the invention, the correction and accurate positioning processing of the shot license plate image is required between the step (2) and the step (3).

As a preferred technical scheme of the invention, in the step (1), a license plate positioning algorithm of an Isotropic Sobel edge detection operator is adopted to position the license plate position.

As a preferred technical solution of the present invention, in the step (3), the license plate is recognized by mainly using the following algorithm:

(1) a character recognition algorithm based on template matching;

(2) based on a feature statistical matching algorithm;

(3) character recognition based on a classifier.

As a preferred embodiment of the present invention, in the step S106, the inquiry signal includes a command requesting to establish communication and data and vehicle information data of the OBU.

The ETC portal roadside reader-writer implementing the method comprises a controller, a read-write module, a communication interface, a modulation module and a microwave antenna, wherein the read-write module and the communication interface are both in bidirectional electric connection with the controller, the modulation module is in bidirectional electric connection with the read-write module, and the modulation module is in bidirectional electric connection with the microwave antenna.

(III) advantageous effects

Compared with the prior art, the ETC portal roadside read-write method and the reader-writer provided by the invention have the following beneficial effects:

this ETC portal roadside reading and writing method and read write line can intercept for the vehicle that is equipped with the ETC, avoid appearing with the phenomenon of car fee evasion, can intercept the vehicle that vehicle license plate and OBU data do not conform to simultaneously, carry out effectual improvement to stealing the ETC card phenomenon of brushing.

Drawings

FIG. 1 is a schematic flow chart of a roadside read-write method of the ETC portal of the present invention;

fig. 2 is a schematic diagram of a module composition structure of the ETC portal roadside reader-writer of the present invention.

In the figure: 100. a controller; 200. a read-write module; 300. a communication interface; 400. a modulation module; 500. a microwave antenna.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Examples

Referring to fig. 1-2, the roadside read-write method of the ETC portal provided by the invention includes the following steps:

s101: when the vehicle passes through the ETC portal roadside, the loop sensor detects the vehicle, and the central management system controls the RSU to work and send a low-frequency modulation signal to the vehicle.

The generation and emission process of the low frequency modulation signal in step S101 is as follows:

(1) the RSU generates a low-frequency carrier signal;

S102: if the vehicle does not feed back the low-frequency modulation signal, the vehicle is not provided with the OBU, and the central management system controls the railing to be closed.

S103: if the vehicle is fed back by the low-frequency modulation signal, the vehicle is equipped with the OBU, and the OBU on the vehicle feeds back the low-frequency modulation signal.

S104: the central management system controls a license plate recognizer on the ETC portal roadside to shoot a license plate of the vehicle and transmits a shot picture to the license plate recognition system.

In step S104, the license plate information recognition step is as follows:

Between the step (2) and the step (3), the photographed license plate image needs to be corrected and accurately positioned, a certain inclination of the license plate in the image is inevitable due to the limitation of the photographing condition, a correction and accurate positioning link is needed to further improve the quality of the license plate image, and a vehicle recognition system is prepared.

In the step (1), a license plate positioning algorithm of an Isotropic Sobel edge detection operator is adopted to position the license plate position, and the algorithm mainly comprises the following processes: inputting a colorful license plate image, graying, edge detection, binaryzation, filtering and denoising, searching a license plate candidate region, removing a fake license plate and outputting the license plate.

In the step (3), the license plate is identified mainly by adopting the following algorithm:

(1) and (3) a character recognition algorithm based on template matching.

The method comprises the steps of firstly establishing a template library, carrying out binarization on characters to be recognized and normalizing the characters, then matching the characters serving as input modes with all templates, and finally selecting the best matching as a result. The algorithm has the advantages that under the conditions that the image quality after preprocessing is high, the inclination degree of the license plate is low, and the textural features of the license plate are clear, the accuracy of recognition is high, but errors are easy to occur when similar characters are recognized due to the omission of character detail information.

(2) And (4) performing a feature statistics based matching algorithm.

The method is based on the principle of a feature statistical matching algorithm and comprises the steps of firstly extracting the statistical features of license plate characters in an input mode, and then classifying and judging the license plate characters according to a certain rule and a determined decision function, wherein the statistical features of the characters comprise the number of pixel blocks, the number of outlines of the characters, the shapes of the outlines and the like, and the pixel blocks refer to the pixel blocks of a connected region formed by all white pixel regions which are mutually connected in the upper direction, the lower direction, the left direction and the right direction of a binary image, so that the pixel blocks of Chinese characters are larger than 1, and the number of the pixel blocks of English letters and numbers is 1.

(3) Character recognition based on a classifier.

Character recognition based on a classifier is a license plate recognition mode which is widely applied at present. The method has the main idea that the data can be automatically classified into known types through learning sample data. The classifier is actually a mathematical model, and there are many types of classifiers including Bayes classifier, decision tree model, BP neural network classifier, etc. the classification principle of the Bayes classifier is that the prior probability of a certain object is used to calculate the posterior probability of the certain object by using the Bayes formula, that is, the probability that the object belongs to a certain class, and the class with the maximum posterior probability is selected as the class to which the object belongs. That is, the bayesian classifier is an optimization in the sense of minimum error rate.

S105: the license plate recognition system recognizes the license plate information and transmits the license plate information to the central management system.

S106: and the OBU sends out an inquiry signal to the RSU beside the ETC portal roadside according to the received low-frequency modulation signal, and the RSU receives the inquiry signal of the OBU and transmits the inquiry signal of the OBU to the central management system.

In step S106, the inquiry signal includes a command requesting to establish communication and data and vehicle information data of the OBU, where the vehicle information data includes vehicle basic information and vehicle driver information.

S107: and the central management system compares the information of the OBU with the license plate information and feeds back the information.

S108: if the information of the OBU is matched with the license plate information, the RSU receives the inquiry signal of the OBU and establishes bidirectional communication and data exchange, and the vehicle normally passes through a toll station to finish the vehicle fee deduction work.

The ETC portal roadside reader-writer implementing the method comprises a controller 100, a read-write module 200, a communication interface 300, a modulation module 400 and a microwave antenna 500, wherein the read-write module 200 and the communication interface 300 are both in bidirectional electrical connection with the controller 100, the modulation module 400 is in bidirectional electrical connection with the read-write module 200, the modulation module 400 is in bidirectional electrical connection with the microwave antenna 500, the controller 100 is connected with an upper computer through the communication interface 300, the upper computer is a PC (personal computer) end provided with a central management system, the adjustment module 400 is used for modulating a low-frequency carrier signal, the microwave antenna 500 is used for reading an OBU (on-board unit) in a 5.8GHz frequency band, the read-write module 200 is used for reading and writing information of the OBU establishing normal bidirectional communication and data exchange with the reader-writer, and then transmitting the information data to the central management system through the controller 100 and the communication interface.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A roadside reading and writing method for an ETC portal is characterized by comprising the following steps:

2. The ETC portal roadside read-write method according to claim 1, characterized in that: the generation and sending processes of the low-frequency modulation signal in the step S101 are as follows:

(1) the RSU generates a low-frequency carrier signal;

3. The ETC portal roadside read-write method according to claim 1, characterized in that: in step S104, the license plate information recognition step is as follows:

4. The ETC portal roadside read-write method according to claim 3, wherein: and (3) correcting and accurately positioning the shot license plate image between the step (2) and the step (3).

5. The ETC portal roadside read-write method according to claim 3, wherein: in the step (1), a license plate positioning algorithm of an Isotropic Sobel edge detection operator is adopted to position the license plate position.

6. The ETC portal roadside read-write method according to claim 3, wherein: in the step (3), the license plate is identified mainly by adopting the following algorithm:

(1) a character recognition algorithm based on template matching;

(2) based on a feature statistical matching algorithm;

(3) character recognition based on a classifier.

7. The ETC portal roadside read-write method according to claim 1, characterized in that: in step S106, the inquiry signal includes a command requesting to establish communication and data and vehicle information data of the OBU.

8. An ETC portal roadside reader/writer that implements the method of any one of claims 1 to 7, characterized by: the microwave antenna comprises a controller, a read-write module, a communication interface, a modulation module and a microwave antenna, wherein the read-write module and the communication interface are both in bidirectional electric connection with the controller, the modulation module is in bidirectional electric connection with the read-write module, and the modulation module is in bidirectional electric connection with the microwave antenna.