CN102110892A

CN102110892A - Low-standing-wave ratio and ultra-wide band planar slot antenna

Info

Publication number: CN102110892A
Application number: CN2010106112017A
Authority: CN
Inventors: 钟顺时; 孔令兵
Original assignee: SHANGHAI UNIVERSITY
Current assignee: SHANGHAI UNIVERSITY
Priority date: 2010-12-29
Filing date: 2010-12-29
Publication date: 2011-06-29
Anticipated expiration: 2030-12-29
Also published as: CN102110892B

Abstract

The invention relates to a low VSWR ultra-wideband planar slot antenna, which consists of a dielectric substrate (3), a microstrip feeder guide strip printed on the front of the dielectric substrate (3), an elliptical ring feed terminal (2) and a sticker Consists of a metal floor attached to the back of the dielectric substrate (3). . The microstrip feeder conductor strip consists of a 50-ohm microstrip line, a gradient microstrip line whose characteristic impedance linearly changes from 50 ohms to R (about 60-100) ohms, and a three-pronged microstrip line conductor strip. The wide slit is a polygon plus a semi-elliptical combined slit, and its lower edge protrudes inward. SMA or N-type coaxial connectors are arranged on the metal floor, and the inner conductor (probe) of the connector passes through the dielectric substrate and is connected to the 50-ohm microstrip line conductor strip on the front of the antenna. This connector is connected to an external 50 ohm coaxial feeder to feed the antenna. The voltage standing wave ratio of the antenna in the 780-3000MHz frequency band is not greater than 1.5, so as to meet the requirements of the domestic mobile communication system for the standing wave ratio performance standard, and can cover all common frequency bands of mobile communication. It has a planar printing structure, low profile, simple fabrication, low cost, and is suitable for mass production.

Description

Low standing-wave ratio super wide band plane slot antenna

Technical field

The present invention relates to a kind of novelty that is used for mobile communication system and beautify flat plane antenna, particularly satisfy the low standing-wave ratio super-wide-band flat antenna of China Mobile.

Background technology

Microstrip antenna have planar structure, low, in light weight, the easy manufacturing of section, can with plurality of advantages such as microwave circuit is integrated, (write referring to the clock up time, microstrip antenna is theoretical and use publishing house of Xian Electronics Science and Technology University to have obtained extensive use under conventional environment, Xi'an, 1991).A lot of all channel antenna technology have been developed in recent years and (referring to the clock up time, Liang Xianling, it is flourish to prolong dawn, the super-wide-band flat antenna technology, the electric wave science journal, the 22nd volume, the 2nd phase, pp.308 – 315,2007.4), document (J.-Y. Sze and K.-L. Wong, Bandwidth enhancement of a microstrip line-fed printed wide-slot antenna, IEEE Trans. Antennas Propag. Vol. 49, No. 7, pp. 1020 – 1024, Jul. 2001) the wide seam antenna to a feed microstrip line comes widening frequency band, document (F.W.Yao, S.S.Zhong with fork shaped microstrip minor matters, W.Wang and X.L.Liang, Wideband slot antenna with a novel microstrip feed, Microwave Optical Technology Letters, 46 (3), pp.275-278 Aug.2005) comes the frequency band of broadening slit microstrip antenna with fan-shaped offset of microstrip feed and little band minor matters.It is standard that the bandwidth of above ultra-wideband antenna all is not more than 2 with voltage standing wave ratio.

It is less than 2 that many countries such as America and Europe require the mobile communication antenna voltage standing wave ratio.By this standard, lot of domestic and international company has developed a lot of indoor covering ultra wideband microstrip antennas.But China's mobile communication antenna is relatively strict to the voltage standing wave ratio performance requirement, requires its standing-wave ratio in bandwidth otherwise greater than 1.5.And existing indoor cover antenna still can not satisfy China's mobile communication system mostly to this low standing-wave ratio performance demands.

Summary of the invention

The object of the invention is to provide a kind of low standing-wave ratio super wide band plane slot antenna at the deficiency of prior art existence.It is not more than 1.5 at 800～3000MHz frequency range standing internal wave than all, thereby can cover the frequency band of each mobile communication system in the general frequency range of 800～3000MHz, as GSM(890～960MHz), DCS(1710～1880MHz), PCS(1850～1990MHz), UMTS(1920～2170MHz, WLAN(2400～2484MHz) and LTE(2600～2700MHz) etc.It has the planographic structure, and section is low, and is simple in structure, and cost is low, makes high conformity, is fit to large-scale mass production.

The present invention design is: based on the ultra-wideband antenna principle, realize that finite length minimizes and to the maximized practical application of dependence of angle.The present invention adopts custom-designed wide slit, and this wide slit is that polygon adds half elliptic combination slit, and slit bottom is protruding upward, and bossing is trapezoidal; This trapezoidal base angle size has key effect to antenna standing wave ratio, and the size of tuning this angle realizes the ultra broadband impedance operator.The microstrip feed line conduction band is connected and composed successively by one section 50 ohm microstrip, one section gradual change microstrip line and trident microstrip line conduction band, and the microstrip feed line terminal is the oval ring feed, and this has guaranteed ultra broadband coupling of antenna and 50 ohm of feeder lines.

According to above-mentioned inventive concept, the present invention has adopted following technical proposals:

A kind of low standing-wave ratio super wide band plane slot antenna is made of medium substrate, microstrip feed line conduction band and the oval ring feed terminal printed in the medium substrate front and the metal floor that is attached to the medium substrate back.It is characterized in that:

A. the microstrip feed line conduction band is made up of from gradual change microstrip line and trident microstrip line conduction band that 50 ohm of linearities are gradient to R ohm one section 50 ohm microstrip, characteristic impedance;

B. described feed terminal is the oval ring metal patch;

C. described metal floor is the metal patch that has wide slit;

D. described wide slit is that polygon adds the half elliptic combined shaped, and this shape bottom inwardly protruding is trapezoidal, and this trapezoidal base of going up is in microstrip feed line conduction band and oval ring feed terminal connecting place.

The microstrip feed line conduction band is connected to form from gradual change microstrip line and the trident microstrip line conduction band that 50 ohm of linearities are gradient to R ohm successively by one section 50 ohm microstrip, one section characteristic impedance.The length of one section 50 ohm microstrip conduction band is 2mm～15mm in the microstrip feed line conduction band; From 50 ohm of length to R ohm transition line conduction band is 20mm～40mm; Trident microstrip line conduction band longitudinal length is 3mm～20mm, and lateral length is 5mm～30mm; R is about 60 ~ 100(ohm).

The terminal that links to each other with the microstrip line conduction band is the oval ring metal patch, and its outer oval major semiaxis is 13mm～25mm, and semi-minor axis is 1mm～15mm; Interior oval major semiaxis is 13mm～25mm, and semi-minor axis is 1mm～15mm.

The relative dielectric constant of described medium substrate is 2～10; Thickness has only 0.5mm～3mm magnitude.

Described wide slit is that polygon adds half elliptic combination slit, its shape is basic shape with rectangle mainly, and this rectangular top is a half elliptic, its bottom inwardly protruding, bossing is that trapezoidal, the trapezoidal upper base and the horizontal edge projector distance of trident microstrip line conduction band are 0.5mm～5mm.

The bottom surface metal floor is provided with SMA or N type coaxial fitting, and the joint inner wire passes dielectric substrate and links to each other with 50 ohm microstrip conduction bands of antenna face; The external 50 ohm of coaxial feeders of this joint come antenna feed.

The present invention compared with prior art has following conspicuous outstanding substantive distinguishing features and remarkable advantage:

The present invention can realize that 780～3000MHz frequency band standing internal wave is not more than 1.5 than all, thereby satisfies domestic mobile communication system to the low standing-wave ratio performance demands of antenna, can cover each general frequency range of mobile communication.The present invention has adopted custom-designed polygon to add the slit of half elliptic combined shaped and the combination of oval ring feed terminal, main by changing the base angle a size of polygon inwardly protruding part, realized the ultra broadband characteristic of Antenna Impedance Matching, and has a planographic structure, section is low, simple in structure, cost is low, is fit to large-scale mass production.

Description of drawings

The front view of Fig. 1 antenna of the present invention;

The end view of Fig. 2 antenna of the present invention;

The concrete enforcement dimensional drawing of Fig. 3 antenna example of the present invention;

The standing-wave ratio curve chart of Fig. 4 antenna example;

The 880MHz directional diagram of Fig. 5 antenna example;

The 2150MHz directional diagram of Fig. 6 antenna example.

Embodiment and example

Details are as follows in conjunction with the accompanying drawings for the preferred embodiments of the present invention:

Embodiment one: referring to Fig. 1 and Fig. 2, a kind of low standing-wave ratio super wide band plane slot antenna of local standing-wave ratio super wide band plane slot antenna is made of medium substrate 3, microstrip feed line conduction band and the oval ring feed terminals 2 printed in medium substrate 3 fronts and the metal floor that is attached to medium substrate 3 backs.The microstrip feed line conduction band is made up of from gradual change microstrip line and trident microstrip line conduction band that 50 ohm of linearities are gradient to R ohm one section 50 ohm microstrip, characteristic impedance; Described feed terminal 2 is the oval ring metal patch; Described metal floor 6 is for having the metal patch in wide slit 1; Described wide slit 1 adds the half elliptic combined shaped for polygon, and this shape bottom inwardly protruding is trapezoidal, and this trapezoidal base of going up is in microstrip feed line conduction band and oval ring feed terminal 2 connecting places.

Embodiment two: present embodiment and example 1 are basic identical, and this low standing-wave ratio super wide band plane slot antenna is by the microstrip feed line conduction band that is printed on medium substrate 3 fronts and oval ring feed terminal 5, medium substrate 3, constitute with the metal floor 2 that has wide slit 1.The microstrip feed line conduction band is gradient to R(about 60～100 by one section 50 ohm microstrip, characteristic impedance from 50 ohm of linearities) ohm gradual change microstrip line and trident microstrip line conduction band form.Wide slit 1 adds half elliptic combination slit for polygon, and its shape is basic shape with rectangle mainly, this rectangular bottom inwardly protruding.Metal floor 2 is provided with SMA or N type coaxial fitting 4, and joint 4 inner wires (probe) pass dielectric substrate and link to each other with 50 ohm microstrip conduction bands of antenna face.These joint 4 external 50 ohm of coaxial feeders come antenna feed.

The concrete size of example antenna is shown among Fig. 3.The medium substrate material of this example antenna is FR-4, and its relative dielectric constant is 4.4, and substrate thickness is 1.6mm.

Fig. 4 is the standing-wave ratio figure of this concrete antenna example emulation.As seen from the figure, compare all less than 1.5 at 780MHz～3000MHz frequency range standing internal wave.

Fig. 5 and Fig. 6 are the emulation directional diagram of this concrete antenna example at two frequencies.Can see that by figure the lobe of directional diagram helps enlarging the coverage of antenna like this than broad.

Claims

1. A low VSWR ultra-wideband planar slot antenna, consisting of a dielectric substrate (3), a microstrip feeder conductor strip printed on the front of the dielectric substrate (3), an elliptical ring feed terminal (2) and affixed to the dielectric substrate (3). The metal floor on the back of the substrate (3); is characterized in that:

a. The guide strip of the microstrip feeder is composed of a 50 ohm microstrip line, a gradient microstrip line whose characteristic impedance linearly changes from 50 ohms to R ohms, and a three-pronged microstrip line guide strip;

b. The feed terminal (2) is an oval ring metal patch;

c. The metal floor (6) is a metal patch with a wide gap (1);

d. The wide gap (1) is a combined shape of a polygon and a semi-ellipse. The bottom of the shape protrudes inwards to form a trapezoid. place.

2. The low standing wave ratio ultra-wideband planar slot antenna according to claim 1, characterized in that the length of a section of 50 ohm microstrip line in the microstrip line conduction band (5) is 2 mm to 15 mm; from 50 ohm to The length of the R ohm microstrip line is 20 mm to 40 mm; the longitudinal length of the trifurcated microstrip line is 3 mm to 20 mm, and the transverse length is 5 mm to 30 mm; the value range of R is 60 to 100 ohms.

3. The low VSWR ultra-wideband planar slot antenna according to claim 1, characterized in that in the elliptical ring feed terminal (2), the major semi-axis of the outer ellipse is 13mm-25mm, and the minor semi-axis is 1mm-15mm ; The semi-major axis of the inner ellipse is 13 mm to 25 mm, and the semi-minor axis is 1 mm to 15 mm.

4. The low standing wave ratio ultra-wideband planar slot antenna according to claim 1, characterized in that the relative dielectric constant of the dielectric substrate (3) is 2-10; the thickness is only on the order of 0.5mm-3mm.

5. The low VSWR ultra-wideband planar slot antenna according to claim 1, characterized in that the wide slot (1) is a combination of polygon and semi-ellipse, with a rectangle as the base shape, and the top edge of the rectangle is It is semi-elliptical, the bottom edge of which is convex inward, and the convex part is trapezoidal, and the projected distance between the upper bottom of the trapezoid and the transverse side of the conduction band of the trident microstrip line is 0.5 mm to 5 mm.

6. The low VSWR ultra-wideband planar slot antenna according to claim 1, characterized in that an SMA or N-type coaxial connector (4) is provided on the bottom metal floor (6), and the inner conductor of the connector (4) Pass through the dielectric substrate (3) and connect to the 50-ohm microstrip line conduction tape on the front of the microstrip feeder (5); the connector (4) is externally connected to a 50-ohm coaxial feeder to feed the antenna.