CN201117814Y

CN201117814Y - Label antenna

Info

Publication number: CN201117814Y
Application number: CNU2006200483099U
Authority: CN
Inventors: 菅洪彦
Original assignee: KUNRUI ELECTRONIC SCIENCE-TECHNOLOGY Co Ltd SHANGHAI
Current assignee: KUNRUI ELECTRONIC SCIENCE-TECHNOLOGY Co Ltd SHANGHAI; Shanghai Quanray Electronics Co Ltd
Priority date: 2006-11-30
Filing date: 2006-11-30
Publication date: 2008-09-17
Anticipated expiration: 2016-11-30

Abstract

The utility model relates to a tag antenna, the structure of which is that two arms of the antenna are shaped like an oyster shell, wherein the small ends of the oyster-shell-shaped arms are connected with each other through a bending connection curve (31); a closed metal ring is arranged at a feeding point (32), and the metal ring is formed a matched inductance ring (33). The tag antenna of the utility model realizes the beauty and practicability by designing two arms of the doublet antenna in the shape of oyster shell.

Description

A kind of label antenna

Technical field

The utility model belongs to antenna technical field, relates to a kind of high performance label antenna.

Background technology

In recent years, automatic identifying method is in many service fields, aspect sale of goods and the logistics distribution, in commercial department, obtained popularizing fast and promoting in manufacturing enterprise and the material field of circulation.

Several years ago, bar code---paper tape has caused a revolution and has obtained extensive use in the recognition system field.Today, this bar code---paper tape can not satisfy people's demand under increasing situation.Though bar code is very cheap, its weak point is that storage capacity is little and can not rewrite.

A kind of technical best solution be with storage in a silicon.In daily life, having the IC-card of arranging the contact (phone IC-card, bank card etc.) is the most general structure of electric data carrier.Yet concerning IC-card, in many cases, the connection of mechanical contact is insecure.Data between the reader under data medium and one are carried out non-contact transmission with much flexible.According to the energy and the data transmission method that use, we are called radio-frequency recognition system (RFID-Radio Frequency Identification) to non-contacting recognition system.Therefore, RFID is that a kind of radio wave that utilizes is read and write programmed recording medium, radio-frequency technique is combined with the IC-card technology and can be used for the technology of remote, moving-target, wireless identification.

Rfid system is in concrete application process, and according to different application purposes and applied environment, the composition of system can be different, but with regard to its operation principle, system generally all is made up of transponder, reader and PC.Transponder should be placed on the object that will discern, can send and receive information, and can do processing such as read/write according to the operational order of receiving; Reader is to gather transponder information and transponder is sent the device of operational order, and the order of sending comprises read/write, selects order such as cancellation selections grade.

Antenna is a critical component in radio communication and the radar system as the equipment of a kind of reception and launching electromagnetic wave, and it is the interface of free space and transmission line, is commonly referred to " electronic eyes " or " electronic ear ".The effect of antenna in various radiotechnics equipment is identical basically.Any radiotechnics equipment all transmits signal by electromagnetic wave, and it must have the energy radiation or receive electromagnetic device, and antenna is exactly this device, so the effect of antenna at first is exactly radiation and receives electromagnetic wave.Based on such prerequisite, since the generation of wireless communication technique, antenna just has been born thereupon.

From the simplest wire antenna, surface antenna, antenna technology has experienced innovation for several times.Along with the expansion in antenna applications field, being showing improvement or progress day by day of wireless communication technology, people are more and more higher to the requirement of antenna: operating distance is far away as much as possible, and it is big as much as possible to gain, and power consumption is as much as possible little, and efficient is high as much as possible, and polarization is coupling or the like as much as possible.In recent years again utility model technology such as microstrip antenna and antenna array, make antenna be applied in more field, intelligence communication field particularly is such as the TD-SCDMA mobile phone.

Electronic tag prints on paper or the plastic film for the label that reduces cost often adopts, and label is attached to and means to have different resonance frequencys on the different objects like this.The environment of periphery is also bigger to the resonance frequency influence of electronic tag.Also having the frequency range of the electronic tag of UHF is 860MHz-960MHz, than the frequency band of broad, guarantee that country variant uses certain frequency band wherein, and label can use in any country.It is very necessary designing wide band electronic label antenna for this reason.

The most frequently used form of label antenna is half-wave dipole or short dipole, and shown in Fig. 1 a and Fig. 1 b, Fig. 1 a is the schematic diagram of the dipole antenna of routine, and Fig. 1 b is the dipole antenna schematic diagram that the electric capacity cap loads form, but its frequency band is not wide relatively.

Common element antenna is as resonant antenna, and its electric current is standing wave and distributes. and input resistance and input reactance all are the sensitivity functions of its electrical length.Especially input reactance, not only its size sharply changes with the electrical length of antenna, and its character also is cyclic variation with electrical length.Theory analysis and experimental result show that all the severe degree that the input impedance of element antenna changes with electrical length depends primarily on the antenna characteristics impedance.Characteristic impedance is big more, and input impedance is strong with regard to Shaoxing opera with the variation of electrical length, and the impedance bandwidth of antenna is just narrow more, otherwise. characteristic impedance is more little. and the impedance bandwidth of antenna is just wide more.The characteristic impedance of element antenna depends primarily on slenderness ratio.Conventional wide band flat plane antenna has triangle antenna.Conventional triangle antenna (claiming bow-tie antenna again) is a kind of planar structure.The structure of triangle dipole antenna is as follows: two arms of oscillator are made isosceles triangle, shown in Fig. 2 b, also can make fan-shaped, as Fig. 2 a or other shape, Fig. 2 a is fan-shaped dipole antenna configuration schematic diagram, Fig. 2 b isosceles triangle dipole antenna configuration schematic diagram.

Antenna can be described as filter to a certain extent, has only the signal of some frequency range to receive and dispatch, and the frequency bandwidth that therefore increases antenna can also adopt the method for multistage matching network.

The utility model content

The purpose of this utility model is to propose a kind of high performance label antenna of design, makes the raw material of antenna with minimizing, and then reduces the cost of antenna and the matching network that chip constitutes wideband.

The technical solution of the utility model is as follows:

A kind of label antenna comprises two arms, and its characteristics are that described two arms are shell shaped, and the little head end of these conchoidal two arms is connected by the line curve of bending; Be provided with closed becket at described routed electric some place, this becket constitutes the coupling inductive loop.

Conchoidal two arms that constitute dipole antenna are the keel shape.Described junction curve is a broken line.

Because the impedance meeting of triangle antenna just along with its electrical length changes, is not easy to be designed to the impedance matching (complex conjugate just) with chip.The utility model is located to connect crooked broken line the microcephaly of fan-shaped shell, and near the broken line back of the body routed electricity point of antenna connects into inductive loop, and chip and label antenna have just constituted the matching network of wideband like this.Beautiful fan-shaped shell contour shape has constituted two arms of antenna, adopts the profile form can reduce the raw material of making antenna, and then reduces the cost of antenna.

Description of drawings

Fig. 1 a is the schematic diagram of the dipole antenna of routine.

Fig. 1 b is the schematic diagram that the electric capacity cap loads the dipole antenna of form.

Fig. 2 a is the structural representation of fan-shaped dipole antenna.

Fig. 2 b is the structural representation of isosceles triangle dipole antenna.

Fig. 3 is the schematic diagram of a kind of label antenna of the utility model.

Among the figure,

The routed electricity point of 30-keel shape 31-junction curve 32-33-coupling inductive loop

Embodiment

Further specifically describe the utility model antenna below in conjunction with the accompanying drawing example.

Fig. 3 is the schematic diagram of a kind of label antenna of the utility model.As seen from the figure, two arms of antenna are shell shaped, and the keel shape 30 of shell has constituted dipole antenna two arms; Little head end in shell shaped links to each other with the routed electricity point 32 of antenna by junction curve 31; Routed electricity point 32 places at antenna have closed becket to constitute coupling inductive loop 33.

It should be noted last that, above embodiment is only unrestricted in order to the explanation the technical solution of the utility model, although the utility model is had been described in detail with reference to preferred embodiment, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement the technical solution of the utility model, and not breaking away from the spirit and scope of technical solutions of the utility model, it all should be encompassed in the middle of the claim scope of the present utility model.

Claims

1. a label antenna comprises two arms, it is characterized in that, described two arms are shell shaped, and the little head end of these conchoidal two arms is connected by crooked junction curve (31); Locate to be provided with closed becket at described routed electric point (32), this becket constitutes coupling inductive loop (33).

2. a kind of label antenna according to claim 1 is characterized in that, the keel shape (30) of shell constitutes two arms of dipole antenna.

3. a kind of label antenna according to claim 1 is characterized in that, described junction curve is a broken line.