CN201146244Y

CN201146244Y - Circular-polarization antenna with small volume

Info

Publication number: CN201146244Y
Application number: CNU2006200427900U
Authority: CN
Inventors: 菅洪彦
Original assignee: KUNRUI ELECTRONIC SCIENCE-TECHNOLOGY Co Ltd SHANGHAI
Current assignee: KUNRUI ELECTRONIC SCIENCE-TECHNOLOGY Co Ltd SHANGHAI
Priority date: 2006-06-13
Filing date: 2006-06-13
Publication date: 2008-11-05
Anticipated expiration: 2016-06-13

Abstract

The utility model discloses a small volume circularly polarized antenna. A grounding soleplate of the antenna can be folded to form a flank wall; the grounding soleplate and the flank wall vertical to the grounding soleplate form a metal box with five surfaces connected and one surface opened. A radiator element of the antenna is a square ring, which is arranged at the opening part of the grounding soleplate and is supported by a non-conducting object. An impedance matching line of the antenna is extracted from one corner of the radiator element, which forms an impedance matching network inside the radiator element along the diagonal. The feeding position of the antenna is arranged on the impedance matching network. The utility model realizes the circularly polarized antenna with high-gain, large antenna front-to-rear ratio and small volume.

Description

A kind of small size circular polarized antenna

Technical field

The utility model belongs to antenna technical field, relates to the high performance circular polarized antenna of a kind of small size.

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 FrequencyIdentification) 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.Invented technology such as microstrip antenna and antenna array in recent years again, made antenna be applied in more field, intelligence communication field particularly is such as the TD-SCDMA mobile phone.

Generally speaking label all is designed to the form of linear polarization, and it is put may be any direction, and this cooperates the read-write of label antenna with regard to the reading and writing device antenna that needs circular polarization.Circular polarization means how read write line rotates the communication distance of the system of not influencing in the plane of antenna.Handheld device wants cube little in light weight, and the antenna of the high-performance small size of circular polarization is for various application, and especially radio-frequency (RF) identification handhold read-write device has very big meaning.

For handheld device, owing to be that the people holds electromagnetic field emissions equipment, need antenna to have good front and back ratio, make substantially all emissions in front of electromagnetic field, the operating personnel of handheld device are avoided or reduce electromagnetic radiation.

Fig. 1 and Fig. 2 are conventional microstrip structure antennas.Conventional paster antenna (or being called microstrip antenna) is that the paster 10 (radiation fin of antenna just) by the antenna among Fig. 1 comes radiated electromagnetic wave; Its ground connection base plate 11 is planar structures; By realizing impedance matching as the back of the body feedback of the distributing point 23 of Fig. 2 or the form of limit feedback.

Summary of the invention

For overcoming the deficiency of above-mentioned prior art, the technical problems to be solved in the utility model provides a kind of small size circular polarized antenna.

For solving the problems of the technologies described above, technical scheme of the present invention is:

A kind of small size circular polarized antenna, the square ground connection base plate of this antenna is folded up the formation abutment wall, and five perpendicular of abutment wall formation of this ground connection base plate link to each other, the can of an opening.

The radiation fin of this antenna is Fang Huan, is placed on described ground connection base plate opening part, uses nonconducting object support.

The impedance matching line of this antenna is drawn from an angle of described radiation fin, forms impedance matching network in the inside of described radiation fin along diagonal, and the feed placement of this antenna is at this above impedance matching network.

Compared with prior art, the invention has the beneficial effects as follows:

The utility model has designed the abutment wall that is connected with the ground connection sole plate metal, cooperates the aerial radiation sheet of Fang Huan, by impedance matching network partly being put into the inner circular polarized antenna of realizing high-performance, small size of radiation fin side's ring of antenna.

The gain of microstrip antenna and front and back ratio are all along with the ground connection base areas of antenna ground increases and increases.But this requires with the antenna of small size and trend contradicts.Here turn up around will the ground connection base plate, make its box-shape that forms an opening, so Deng Xiao increase the effective area of ground connection base plate of antenna.Compare with the plane ground connection base plate antenna of identical size, this structure can increase the front and back ratio of antenna greatly.

Conventional microstrip structure adopts the radiating element of an integral body, and the impedance matching network that adopts the back of the body to present or be put into the radiating element outside is realized the coupling of impedance.But the area of the antenna that complete radiating element needs is bigger, can adopt the method for hollow out in the middle of the radiating element is dwindled its area.The impedance matching network that is put into the radiating element outside can increase the area of antenna.At the ring-type radiating element of middle hollow out, impedance matching network just can be put into the inside of radiating element, so just can reduce the area of antenna greatly.

Description of drawings

Fig. 1 is the stereogram of the microstrip antenna of routine;

Fig. 2 is the end view of the microstrip antenna of routine;

Fig. 3 is the stereogram of small size circular polarized antenna;

Fig. 4 is the vertical view of small size circular polarized antenna.

Number in the figure: the 10th, the paster of antenna (radiation fin of antenna just); The 11st, the ground connection base plate; The 12nd, the medium between antenna and the ground plate; The 20th, the paster of antenna (radiation fin of antenna just); The 21st, ground plate; The 22nd, the medium between antenna and the ground connection base plate; The 23rd, distributing point; The 30th, the paster of antenna; The 31st, the ground connection base plate; The 32nd, the abutment wall that is connected with the ground connection base plate; The 33rd, the impedance matching network of antenna; The 34th, the feed line of antenna; The 35th, the through hole on paster; The 36th, the through hole on the base plate; The 40th, the paster of antenna; The 41st, the ground connection base plate; The 42nd, the abutment wall that is connected with the ground connection base plate; The impedance matching network of 43 antennas; The 44th, the feed line of antenna; The 45th, on the paster and base plate on through hole.

Embodiment

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

See also the stereogram of Fig. 3 the utility model small size circular polarized antenna and the vertical view of Fig. 4 the utility model small size circular polarized antenna.This novel small size circular polarized antenna, the square ground connection base plate 31 of this antenna are folded up and are constituted abutment wall 32, and these ground connection base plate 31 five perpendicular of abutment walls 32 formation link to each other, the can of an opening.

The radiation fin of this antenna, promptly the paster 30 of antenna is Fang Huan, is placed on the opening part of described ground connection base plate 31, uses nonconducting object support.

The impedance matching line of this antenna is drawn from an angle of described radiation fin, forms impedance matching network 33 in the inside of described radiation fin along diagonal, and the feed placement of this antenna is at this above impedance matching network 33.

The design ground connection base plate 31 or 41 of this new antenna is folded up, and constitutes the abutment wall 32 and 42 that is connected with the ground connection base plate, and the ground connection base plate no longer is the base plate on plane like this, but five link to each other the box of an opening.

The annular shape of the paster 30 of antenna and 40 sides of being designed to can dwindle the paster area of antenna so greatly, makes that antenna just can resonance under little area.In other words be exactly the resonance frequency that has reduced the small size paster.

The circular polarized antenna of conventional paster structure can be realized circular polarization and impedance matching by select a feed placement on the diagonal of antenna.This new antenna is drawn the impedance matching line at the diagonal of the paster 30 of the antenna of Fang Huan in side's ring, constitute impedance matching network 33 or 43, and then has reduced the area of antenna when having realized circular polarization.In feed placement,, cooperate impedance matching network 33,43 to realize impedance matching by choose reasonable as the feed line 34 and 44 of the antenna in the example.

Medium between the antenna among Fig. 3 and Fig. 4 is an air, (such structure is fit to the form of medium of non-air equally), therefore need be with fixing between paster and the ground connection base plate, what this novel example adopted is that between is got through the hole, see at the through hole on the paster 35, at the through hole on the base plate 36 with at the through hole on the paster and on the base plate 45, adopt nonmetallic nylon screw to support.Certainly can adopt foam to do supporting object in the middle of this example.So just fixed the position between the base plate of paster and ground connection.If pcb board, the intermediate medium of pcb board just plays a part to support two sheet metals up and down naturally so.

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 kind of small size circular polarized antenna is characterized in that: the square ground connection base plate of this antenna is folded up the formation abutment wall, and five perpendicular of abutment wall formation of this ground connection base plate link to each other, the can of an opening.

2, small size circular polarized antenna according to claim 1, it is characterized in that: the radiation fin of this antenna is Fang Huan, is placed on described ground connection base plate opening part, uses nonconducting object support.

3, small size circular polarized antenna according to claim 2, it is characterized in that: the impedance matching line of this antenna is drawn from an angle of described radiation fin, form impedance matching network in the inside of described radiation fin along diagonal, the feed placement of this antenna is at this above impedance matching network.