Electric vehicle anti-theft system solution

　　1. Project background

Electric vehicles are becoming more and more popular because of their low prices and convenient travel. Every time when commuting to and from get off work, there will be a “long flow” of electric vehicles on the slow roads on both sides of the road. But electric cars also have troubles. Careful people will find that many electric cars have an extra lock on the outside of the battery to prevent theft. Even so, the theft of electric vehicles is not uncommon.

It is understood that in 2008, there were 17,034 cases of theft of electric vehicles in Hangzhou, 40% of which occurred at the door of residents. Even the electric cars parked downstairs will be stolen. I originally thought that there should be no problem with the safety of the cars in the community. I didn’t expect people to steal the electric cars in front of the house. The security of the community is also very helpless: “There are surveillance facilities such as cameras in the community, but it is difficult to ensure that it can cover the corners of the community. The current thieves are very skilled in theft. Lock picking seems to be no different from unlocking. This kind of thing is hard to guard against.”

　　2. System composition

The electric vehicle anti-theft system in the park consists of RFID tags, card readers, antennas, sound and light alarms, and background management. The functions of each part are introduced as follows:

2.1 RFID tags

The installation of on-board tags is roughly divided into two categories due to the wide variety of electric vehicles. As shown in the figure below, for the first category of electric vehicles, the label is installed on the license plate, and for the second category of electric vehicles, the label is installed on the rear wheel of the electric vehicle. Clay tablet.

For the use of tags, we recommend using Impinj Monza 4 chips. Monza 4 RFID tag chips have excellent read and write reliability, support true omnidirectional antenna design, unique privacy protection features and large memory, making it the most reliable and most expensive performance in the industry The label chip.

2.2 Fixed reader

The fixed reader/writer realizes remote data collection and transmits the collected information to the back-end server in real time and accurately.

2.3 Antenna

It is mainly set up at some important doorways to effectively identify some vehicles entering and exiting, and it mainly plays a role of data recognition in the system.

2.4 Card issuer

For writing data to electronic tags, including electric vehicle tags and key tags, we use the card issuer of Ziyue Technology, which can effectively issue cards to meet user needs.

2.5 Sound and light alarm

When the vehicle passes by alone, or when the key tag that matches it is not found when passing by, a photoelectric and sound alarm will occur. At this time, the staff on duty can easily find that the electric vehicle has been stolen.

　　Three, the specific process

First, each electric vehicle user is equipped with two RFID tags containing user information, one is an electric vehicle tag, which is placed on the electric vehicle; the other is a key tag. And the two labels become related. Secondly, install RFID card readers and read-write antennas at the entrances and exits of each park.

When the vehicle passes the RFID read-write antenna at the gate equipped with the speed bump, the reader will find the key tag that matches it after reading the tag of the vehicle. If it finds the key tag, it can pass smoothly. In other words, only the user can pass the key tag together with the paired vehicle.

If the vehicle passes through the detection antenna, and the key tag associated with the vehicle tag is not found, it will automatically alarm. The specific functional block diagram can be seen in Figure 2.

　　Realization of the off-line anti-theft system for electric vehicles in the park

? If there is only one gate in the park, the equipment can be installed at the entrance and exit of the underground garage of the park. The schematic diagram of system installation at the door is shown in Figure 3.

The antenna coverage is the gate, when a person or vehicle with an RFID tag passes through the gate, the reader will collect information in time

? The computer terminal is connected to the RFID system, and the personnel on duty can see the abnormal data through the computer terminal in the duty room (abnormal tag category, tag unique ID number, display time)

? Both the vehicle tag and the key tag can pass alone. When the vehicle passes by alone, or when no matching key tag is found when passing by, an audible and visual alarm will occur. At this time, the theft can be detected in time.

　　System design description:

1. The fixed reader needs to work directly away from the network cable to realize offline operation, and the system connection and operation are required to be stable.

2. The fixed read-write device sets certain rules, such as AA for key tags and BB for vehicle tags. After each data is collected, it can be directly determined by physical judgment to know whether the tags are paired (no need to connect through the network The tag is sent to the central platform for pairing and then returned to the fixed read-write device. Because of uncontrollable factors in the network, the data upload and download timeout causes the electric vehicle to leave the monitoring area and cause the alarm to be untimely), for example: vehicle tags BB00000001 and AA00000001 are A pair of labels, when this pair appears in pairs, it is considered to be a pair of normal labels, when there is only AA key label, ignore it (because there is only a key label, it is a normal phenomenon).

3. When there is an abnormal vehicle, the system should give an alarm. At this time, the fixed read-write device directly sends a weak current signal to the alarm through GPO, and the alarm sounds a siren. At the same time, the fixed read-write device collects and displays the paired abnormal data on an ordinary PC or notebook through the serial port. The software interface displays the abnormal label category, the unique ID number of the label, and the display time.

4. The fixed reader/writer needs a storage device to store the data and recording time of the abnormal tag. After a period of time, the content can be copied out through the external storage device for easy viewing.

System equipment list (according to 200 electric vehicles):

　　4. Introduction of key equipment

4.1 RFID reader

RFID interface protocol: EPCglobal UHF Class 1 Gen 2 / ISO 18000-6C

Certification: Consistency and interactivity in a high-density reader mode environment

Architecture: Processor Intel IXP420 (266 MHz), Linux system 64 MB SDRAM / 64 MB Flash, sensitivity: -80db

Remote management protocol: EPCglobal Reader Management 1.0.1, SNMP v2 with MIB II;

Network services: DHCP, LL A, NTP, HTTP, Telnet, SSH, SNMP, mDNS, DNS-SD

Dense reader protocol: Dense reader mode, listening before sending, automatic triggering and event management

Reader communication protocol: EPCglobal Low Level Reader Protocol (LL RP) 1.0.1 Impinj Mach1

RF power: +30dBm/+32db with extension cable

Power: AC/DC power converter, maximum power 45 watts (120 or 240 VAC)

Communication interface: RS-232 (DB-9F), LAN TCP/IP (RJ-45), 4 GPIO inputs and 8 outputs

Antenna: 4 ports, reverse TNC

Dimensions: 22.7 x 32.4 x 5.7 cm (8.95 in x 12.75 in x 2.25 in)

Weight: 2.7 kg (6 lbs) Working temperature: -20℃ to +55℃ Dust and humidity adaptation: IP54

LED indicator: power, connection, work, antenna 0-3, CPU, read, monitor, failure

Software support: Java and .NET APIs for Impinj reader/writer protocol (Impinj gateway demo program)

Passed certification: FCC Part 15

4.2 Desktop UHF Reader

Model: Ziytek D500 Desktop Card Issuing Machine

RFID card issuer is a card issuer developed by our company. This card issuer is suitable for reading a series of electronic tags working in the UHF frequency band.

RFID card issuers can be used in conjunction with a series of electronic tags to be widely used in tobacco logistics, access control management systems, urban vehicle automatic identification management, highway non-stop toll collection and material management applications.

The RFID card issuer has a built-in small antenna. As a card issuing device, the typical distance for reading electronic tags is 10cm.

　　The function of the system

? Read the ID number or EPC code in a single electronic tag;

? Read and write data in the user data area of ​​the electronic label;

? Good anti-collision performance, can read the ID number or EPC code in multiple electronic tags at the same time;

? Provide USB interface for data communication and power supply to the card issuer;

? LED lights indicate the power supply and working conditions of the card issuer.

RFID card issuer performance indicators:

? Power supply: powered by USB port +5V/250mA (DC);

? Power consumption: less than 1.3W;

? Dimensions: 170 mm×110 mm×40 mm;

? Weight: less than 0.4kg;

? Ambient working temperature: -20℃～+65℃;

? Ambient storage temperature: -40℃～+70℃;

? Communication interface: USB port;

? Operating frequency range: 902MHz ~928MHz;

? RF output power: ≤10.0dBm;

? Power flatness: ≤0.5dBm (902 MHz ~928MHz);

? Output frequency deviation: ≤10ppm;

? Frequency hopping mode can be set: sequential frequency hopping, random frequency hopping;

? Receiving sensitivity: ≤-30dBm@receiving error rate ≤1% (915MHz);

? Receiving error rate: ≤1%@receiving channel sensitivity ≤-30dBm.

Read performance:

The reading distance is related to the output power of the card issuer, antenna and electronic tag;

? Write label distance = read label distance * 70%;

? Single card (ID number or EPC code) reading time is less than 10ms;

? Single card (single byte) write time is less than 20ms;

? Multi-label identification and anti-collision mechanism: follow ISO18000-6B/6C protocol;

? Multi-label recognition rate: ≥ 10 / sec

? Maximum reading tag distance: 10 cm

4.3 Electronic label

High-strength wear-resistant labels can be fixed to carriers such as pallets, metal pallets, and bins in a variety of ways. They can also be designed as an embedded mode type to be integrated with the carrier to meet applications in the harsh environment of the logistics field.

Parameter list

4.4 Reader antenna

The A9028L/R30NF antenna using Laird technology is a circularly polarized panel antenna, which provides signal reception and transmission technology in the 902-928M frequency band. Both the standing wave ratio and the axial ratio are excellent. For this type of antenna, users are allowed For maximum performance. The antenna is mounted in a heavy-duty radome shell and can also be mounted directly on the wall, allowing any wall or mast installation. The antenna is to provide an integrated coaxial pigtail and multiple types of connectors to choose from.

　　characteristic

? Slim

? Very low VSWR and shaft ratio

? Weatherproof cover

? Wide selection of connectors and cables

? Left-hand and right-hand polarized PC version

　Application occasions

? storehouse

? Airport Hospital

? Transportation terminal

? Conveyor belt

? Logistics Management

? Personnel Management

　　about

Hangzhou Ziyue Technology Co., Ltd. focuses on the field of radio frequency identification, providing customers with valuable radio frequency identification solutions. The company has many years of RFID implementation experience. It is currently a top value-added distributor of Impinj. Based on Impinj technology, it provides customers with readers, antennas, various electronic tags, and provides writing services. Ziyue Technology is willing to provide Chinese customers with First-line support.