CN202854862U

CN202854862U - Electronic tag structure having selection and identification functions

Info

Publication number: CN202854862U
Application number: CN 201120516641
Authority: CN
Inventors: 郝先人; 张靖云
Original assignee: Beijing Tongfang Microelectronics Co Ltd
Current assignee: Beijing Tongfang Microelectronics Co Ltd
Priority date: 2011-12-13
Filing date: 2011-12-13
Publication date: 2013-04-03
Anticipated expiration: 2021-12-13

Abstract

The invention relates to an electronic tag structure having selection and identification functions, and relates to radio frequency identification technical field. The electronic tag structure comprises a rectangular substrate, a tag antenna composed of metal wires on substrate surface and a tag body composed of tag chips. The structure is characterized in that the metal wire is divided into two parts, one part is a rectangular metal ring possessing a gap and other part is two dipoles with a door-shaped structure, and bottom of the two dipoles are connected, the metal ring is positioned over the central section of the dipole. The central section of the bottom of the dipole breaks to form a hand trigger position, and two pins of the tag chip and two ends of the gap of the metal ring can form electrical connection. Compared with the prior art, the electronic tag is selectively set by an electronic tag holder as a condition that whether the normal read-write sensitivity is presented to outside or not, and misreading or illegal invasion of the tag can be avoided.

Description

Electronic Tag Structure with selective recognition function

Technical field

The utility model relates to the REID field, particularly has the Electronic Tag Structure of selective recognition function.

Background technology

RFID is the abbreviation of the English (Radio Frequency Identification) of REID, REID is a kind of automatic identification technology that begins to rise the nineties in 20th century, and REID is one and utilizes radiofrequency signal to pass through Space Coupling (alternating magnetic field or electromagnetic field) to realize that contactless information transmission and the information of passing through to transmit reach the technology of identifying purpose.Rfid system is automatically identified destination object and is obtained related data by radiofrequency signal, and identification work need not manual intervention.Wireless version as bar code, the RFID label has the not available waterproof of bar code, antimagnetic, high temperature resistant, long service life, read that distance is large, data can encrypt, store that data capacity is larger, the storage information change waits advantage freely on the label, has broad application prospects at industry-by-industries such as industry-by-industry such as production, retail, logistics, traffic.

In the prior art, the RFID electronic tag is comprised of with the label antenna that is connected with chip label chip.In the application of quite a few super high frequency radio frequency identification, wish that electronic tag has the function of selective recognition, be that read write line is identified the target electronic label accurately, and can not misread near other electronic tag the target electronic label, affect the accuracy of recognition result; Whether the holder as electronic tag also can freely select to be identified by read write line, can protect like this private data of tag holder illegally not stolen.In fact, but the electronic tag of selective recognition is in the supervision field of entrance guard management field, container etc., larger actual demand is arranged, and also do not have in the existing ultrahigh frequency product solution a kind of can allow the user freely control communication means, particularly in information security issue increasingly serious today, this defective has restricted the range of application of ultrahigh frequency electronic tag to a certain extent.

Summary of the invention

For the problem that above-mentioned prior art exists, the purpose of this utility model provides a kind of Electronic Tag Structure with selective recognition function.It can selectively be set as electronic tag whether externally show normal read-write sensitivity by the electronic tag holder, guarantees that label is not misread or illegal invasion.

In order to realize the foregoing invention purpose, the technical solution of the utility model realizes as follows:

Electronic Tag Structure with selective recognition function, the label body that the label antenna that it comprises the substrate of rectangle, be comprised of the metal routing of substrate surface and label chip form.Its design feature is, described metal routing is divided into two parts, and a part is the becket of rectangle and gap, and a part is the dipole that two portal structures and bottom are connected, and becket is positioned at the top at dipole middle part.The position, middle part, bottom of dipole disconnects the trigger position that forms hand, and two pins of label chip form electricity with the two ends of becket opening position and are connected.

The utility model is owing to adopted said structure, and becket and dipole are relatively independent, carry out the exchange of energy between them by the electromagnetic coupled effect.Becket is electrically connected with label chip, and the label antenna impedance is very sensitive to the change in size of becket, and the becket size can make things convenient for and effectively regulate the label antenna impedance so regulate, thus with label chip impedance conjugate impedance match, transmit to reach ceiling capacity.In the communicating by letter of read write line and electronic tag, becket is by the field of electromagnetic coupled effect induction read write line emission, and becket plays a major role in near-field communication; Dipole plays a major role in far-field communication by far-field radiation.Generally, dipole disconnects, and has just lost the function of far-field radiation, only has becket can work in the near field, so read write line and electronic tag can proper communications in the very strong situation of the very near energy of distance, and the far field can't be realized communication fully.When people's hand or other positions of human body are placed on the open position of dipole, because human body itself is conductor, has distributed capacitor and resistance, the connection that dipole arm is disconnected rebulids by the electromagnetic coupled effect, dipole just can be at the far-field radiation electromagnetic wave, and this moment, electronic tag and read write line can be in the far field proper communications.Whether we just can touch by hand and control easily read write line and communicate by letter with electronic tag like this, can not misread in the far field, and private data is leaked.

The utility model is described in further detail below in conjunction with the drawings and specific embodiments.

Description of drawings

Fig. 1 is structural representation of the present utility model;

Fig. 2 is the impedance plot of the utility model label antenna among the embodiment;

Fig. 3 is the impedance plot when the utility model label antenna has hand to trigger among the embodiment;

Fig. 4 is when the utility model label antenna has hand to trigger among the embodiment, the power reflection damage curve figure of label antenna and chip.

Embodiment

Referring to Fig. 1, the label body that the label antenna 3 that the utility model comprises the substrate 1 of rectangle, be comprised of the metal routing 2 on substrate 1 surface and label chip 4 form.Metal routing 2 is divided into two parts, and a part is the becket 5 of rectangle and gap, and a part is the dipole 6 that two portal structures and bottom are connected, and becket 5 is positioned at the top at dipole 6 middle parts.The position, middle part, bottom of dipole 6 disconnects the trigger position 7 that forms hand, and two pins of label chip 4 form electricity with the two ends of becket 5 opening positions and are connected.

Substrate 1 adopts common FR4 printed circuit board (PCB) in the utility model, and thickness is 0.8mm, and specific inductive capacity is 4.4, and loss tangent is 0.02, and label antenna 3 can be enclosed in the iso standard Bai Kanei that size is 86mm * 54mm; The wide of metal routing 2 is 1mm, and the length of side of becket 5 is 12mm, and the spacing of becket and dipole 6 is 1mm.

Passive ultrahigh frequency electronic tag need to obtain energy and finish communication by the electromagnetic wave that the rectification reader sends.In general the input impedance of electronic label chip is plural number, and is capacitive, and this complex impedance that just needs label antenna to have perception forms with it conjugate impedance match, thereby reaches the Energy Transfer maximization.

The ultrahigh-frequency tag chip 4 that the utility model adopts is 34-j150 Ω in the impedance of 922.5MHz frequency.Label antenna 3 is not triggering with hand, and the impedance curve when being in the free space as shown in Figure 2.Solid line represents label antenna 3 impedance real parts with frequency change trend, and dotted line represents that label antenna 3 imaginary impedance are with frequency change trend; The real part of curve display label antenna 3 very little (only having about 1ohm), namely radiation resistance is very little, and care label antenna 3 does not form effective radiation in the far field, can not be in far field and read write line proper communication.

Impedance curve when hand is placed on the trigger position 7 of label antenna 3 as shown in Figure 3, the impedance real part of label antenna 3 was with frequency change trend when solid line represented to have hand to trigger, label antenna 3 imaginary impedance were with frequency change trend when dotted line represented to have hand to trigger; Impedance curve display label antenna 3 is when having hand to trigger, and its impedance real part obviously increases, and namely radiation resistance increases, and care label antenna 3 has radiation loss in the far field, and in the impedance of 922.5MHz frequency is: 32+j156 Ω.When the label antenna 3 that triggers with hand connected label chip 4, the power reflection damage curve as shown in Figure 4.Frequency is in 904MHz ~ 957MHz scope, and reflection loss all is lower than-10dB, in the value of 922.5MHz frequency is-20.7dB.The input impedance of label antenna 3 of the present utility model when having hand to trigger can realize good conjugate impedance match with this label chip impedance at Chinese super high frequency radio frequency identification frequency band range 920MHz ~ 925MHz as can be known, thereby in the far field good readwrite performance is arranged.

Need to prove, technical solutions of the utility model are compatible mutually with the white card size of iso standard, can electronic tag be implanted PVC Ka Jinei by the form of Inlay, outside surface at card identifies the position that finger need to contact, can directly touch antenna like this, just can realize above-mentioned functions, so not only reduce manufacturing cost, also greatly reduce the possibility that produces the electrostatic breakdown chip simultaneously.

Such scheme is a kind of embodiment of the present utility model; multiple different application scheme can be arranged meeting under the feature of the present utility model; as long as these application schemes meet feature of the present utility model, all should belong to rights protection scope of the present utility model.

Claims

1. the Electronic Tag Structure that has the selective recognition function, it comprises the substrate (1) of rectangle, the label body that the label antenna (3) that is comprised of the metal routing (2) on substrate (1) surface and label chip (4) form, it is characterized in that, described metal routing (2) is divided into two parts, a part is the becket (5) of rectangle and gap, a part is the dipole (6) that two portal structures and bottom are connected, becket (5) is positioned at the top at dipole (6) middle part, the position, middle part, bottom of dipole (6) disconnects the trigger position (7) that forms hand, and two pins of label chip (4) form electricity with the two ends of becket (5) opening position and are connected.