CN101320836A

CN101320836A - Broadband inversed F type antenna

Info

Publication number: CN101320836A
Application number: CNA2007101089050A
Authority: CN
Inventors: 陈柏全
Original assignee: Alpha Networks Inc
Current assignee: Alpha Networks Inc
Priority date: 2007-06-04
Filing date: 2007-06-04
Publication date: 2008-12-10
Anticipated expiration: 2027-06-04
Also published as: CN101320836B

Abstract

This invention provides a broadband reverse F type antenna, including an antenna body installed at a circuit board, a short line and a feed-in line; wherein the antenna body is composed of a first part, a second part and a third part; the line width of the first part is shorter than that of the third part; and the second part is installed between the first and third parts, and the line width of the second part is gradually increased from one end to the other end; and the short line is installed at the position between the first part and one grounding surface set by the circuit board and adjacent to one end of the first end and; the feed-in line is installed at the position between the first part and the grounding surface and adjacent to the other end of the first part. Therefore, the effective bandwidth of the broadband reverse F type antenna is easy to be adjusted to cover the needed broadband of the product using the broadband reverse F type antenna because of no any metal between the antenna body and the grounding surface, and the tolerance is effectively increased when mass-production is carried out.

Description

Broadband inversed F type antenna

Technical field

The present invention is relevant for inverted F shaped antenna, refers to a kind of effective expansion frequency range especially, is easy to adjust to the broadband inversed F type antenna of needed frequency band, the tolerance when effectively increasing volume production.

Background technology

Network equipment manufacturing person adds day function of line options (AntennaDiversity) in wireless network access point (Wireless Access Point) or wireless router Wireless Communication Equipment such as (Wireless Router) at present, can have best signal transmitting and receiving quality in the hope of Wireless Communication Equipment, finally reach the purpose that the dead angle is contained and do not had to signal entirely.Therefore, Wireless Communication Equipment is except the antenna that exposes to its casing at present, and the inside of this casing also is provided with another antenna.This another antenna is chip-shaped antenna (Chip Antenna), printed circuit one pole (Monopole) antenna and inverted F shaped antenna etc. mostly.

Wireless Communication Equipment develops towards miniaturization now, make network equipment manufacturing person when the design Wireless Communication Equipment, the circuit board of this Wireless Communication Equipment inside can become more and more little for the space that this another antenna is set, in addition, the demand of inner various parts of this Wireless Communication Equipment and mechanism design, more cause this another Antenna Design space to be subjected to more restriction, cause this another antenna and fail to reach really the purpose of best signal transmitting and receiving quality.Below specify respectively, this another antenna can't reach the reason of the purpose of best signal transmitting and receiving quality:

1, chip-shaped antenna (Chip Antenna) 10:

See also shown in Figure 1, normally by a kind of being referred to as " LTCC (Low TemperatureCo-fired Ceramic; LTCC) " technology manufacturing; the main characteristic of this technology is that volume is minimum; therefore; in the limited inner space of Wireless Communication Equipment; the putting position of chip-shaped antenna 10 obviously has very big elasticity; but chip-shaped antenna 10 is in practical application, because the mechanism and the circuit board 2 coefficient differences of Wireless Communication Equipment inside, often can't put according to the optimum that the product data sheet (Productdata sheet) of chip-shaped antenna 10 is advised, so in the frequency range performance, dislike not enough slightly, and radiation efficiency is unsatisfactory, and uses chip-shaped antenna to need extra cost, can't reach demand cheaply.

2, the printed circuit unipole antenna 12:

See also shown in Figure 2, printed circuit unipole antenna 12 is printed on the circuit board 2 with a microstrip line, the part of this microstrip line is as a feed-in line 122, and the ground plane 20 that this feed-in line 122 is crossed this circuit board 2 extends outward the holding wire 120 that forms.The advantage of this printed circuit unipole antenna 12 be the simple and design of framework easily, as long as can reach the demand of impedance matching, can form arbitrary shape with the existing arrangement space of coincident circuit plate 2.The shape of the printed circuit unipole antenna 12 of various Wireless Communication Equipment, custom and mechanism and circuit board 2 coefficient differences according to different designs person often have very big difference, and the frequency range performance is unsatisfactory, therefore, for causing very big puzzlement in antenna manufacturing and the design.

3, inverted F shaped antenna 14:

See also shown in Figure 3, these inverted F shaped antenna 14 seals are located on the circuit board 2, this circuit board 2 is provided with a ground plane 20 near its marginal position, and this inverted F shaped antenna 14 is by a feed-in line 140, one short-circuit line 142 and an antenna body 144 are formed, wherein this feed-in line 140 joins with an end and this ground plane 20 of short-circuit line 142, end then extends towards the edge of this circuit board 2 in addition, and an end of this antenna body 144 and this short-circuit line 142 join, in addition end extends to along the edge of this circuit board 2 and after end joins in addition of this feed-in line 140, continues to extend one section predetermined length along the edge of this circuit board 2.By as can be known aforementioned, inverted F shaped antenna 14 is distortion of printed circuit unipole antenna 12, compare with printed circuit unipole antenna 12 and inverted F shaped antenna 14, because the special shape of inverted F shaped antenna 14, it is littler than printed circuit unipole antenna 12 to make that inverted F shaped antenna 14 takies the area of circuit board 2 again.See also shown in Figure 4, the width of this feed-in line and short-circuit line all is that 0.85mm, length are all 5mm, spacing to each other is 2.3mm, the width 0.7mm of this antenna body 144, length are 18.63mm, see also shown in Figure 5, after measuring through circuit design verification, at the frequency range that returns between loss-10dB, be between 2.338～2.508GHz, the problem of these inverted F shaped antenna 14 ubiquity frequency range deficiencies.

According to the above, the shortcoming that above antenna 10,12,14 is common, it is undesirable to be all the frequency range performance, makes that coupling error vector amplitude (Couple error vector magnitude (EVM)) is not good, and then influences transmission rate (Throughput).And, therefore, be necessary to develop antenna in the market in fact with broadband, miniaturization and simple shape because the trend of Wireless Communication Equipment miniaturization adds the demand in the mechanism, and the position that antenna is put often is limited.

Summary of the invention

Because aforesaid many disappearances, the inventor is through the permanent research and experiment of making great efforts, and development and Design goes out a kind of broadband inversed F type antenna of the present invention finally, in the hope of by proposition of the present invention, can contribute to some extent society.

A purpose of the present invention provides a kind of broadband inversed F type antenna, be located at a antenna body on the circuit board by seal, one short-circuit line and a feed-in line are formed, wherein keep certain spacing between this antenna body and this ground plane, and comprise a first, one second portion and a third part, and this first is positioned at the position of adjacent this first's one end in the face of a side of this ground plane, a ground plane set to this circuit board extends to form this short-circuit line, this first is positioned at the position of holding in addition near this first in the face of a side of this ground plane, extend to this ground plane, use and form this feed-in line, and, the live width of this first is littler than the width of the live width of third part, the live width of this second portion is held gradually in addition to it gradually by the one end and is enlarged, and an end of this second portion and this first in addition end be connected together mutually, and the end in addition of this second portion is connected together mutually with this third part one end.

So, between this second and third part and this ground plane, owing to there is not any metal, make effective frequency range of this broadband inversed F type antenna, be easy to adjust to and contain the required frequency band of the product that uses this broadband inversed F type antenna, the tolerance when effectively increasing volume production.Can be for convenient your auditor to the object, the technical characteristics and the effect of the present invention, do further understanding and understand, cooperate graphicly now for embodiment, be described in detail as follows:

Description of drawings

Fig. 1 is the schematic diagram of the chip-shaped antenna of prior art;

Fig. 2 is the schematic diagram of prior art printed circuit unipole antenna;

Fig. 3 is the schematic diagram of prior art inverted F shaped antenna;

Fig. 4 is the actual size schematic diagram of prior art inverted F shaped antenna;

Fig. 5 is that the frequency range of Fig. 4 measures schematic diagram;

Fig. 6 is a configuration diagram of the present invention;

Fig. 7 is the schematic diagram of one embodiment of first of the present invention;

Fig. 8 is the schematic diagram of another embodiment of first of the present invention;

Fig. 9 is the schematic diagram of third part one embodiment of the present invention;

Figure 10 is the schematic diagram of second portion one embodiment of the present invention;

Figure 11 is the size indication figure of Fig. 6; And

Figure 12 is that the frequency range of Figure 10 measures schematic diagram.

The main element symbol description:

Circuit board ... 3 antenna bodies ... 40

Short-circuit line ... 42 feed-in lines ... 44

First ... 400 second portions ... 402

Third part ... 404 ground planes ... 30

Embodiment

The present invention is a kind of broadband inversed F type antenna, see also shown in Figure 6, one circuit board 3 is provided with a ground plane 30 in the position near the one lateral edges, this broadband inversed F type antenna then is provided in a side of 30 of a lateral edges of this circuit board 3 and this ground planes, and this broadband inversed F type antenna comprises an antenna body 40, one short-circuit line 42 and a feed-in line 44, wherein this antenna body 40 is by a first 400, one second portion 402 and a third part 404 are formed, wherein the live width of this first 400 is littler than the width of the live width of third part 404, and between an end of this first 400 is held in addition to it, be that maintenance identical live width and uniform distances are formed along these ground plane 30 definite length extended, the end in addition of one end of this second portion 402 and this first 400 joins, and an end line of this second portion 402 is wide suitable with live width this first 400, and towards expanding gradually away from the direction of this first 400 and extending, up to its in addition live width and this third part 404 of end live width quite till, an end of this third part 404 is held to keep live width and uniform distances identical between these third part 404 two ends formed along these ground plane 30 definite length extended in addition by this two part 402.And, this first 400 is positioned at the position of adjacent these first's 400 1 ends in the face of a side of this ground plane 30, extend to this ground plane 30, use and form this short-circuit line 42, this first 400 is positioned at the position of holding in addition near this first 400 in the face of a side of this ground plane 30, extend and be connected to the set signal transmitting and receiving loop 46 of this circuit board 3 to this ground plane 30, use forming this feed-in line 44.So, there are not any metal in 30 of this antenna body 40 and this ground planes, and effective frequency range of this broadband inversed F type antenna is not increasing under the extra match circuit (Matching Circuit), can be easy to adjust to the needed frequency band of product, the mechanism shell design of tolerance when effectively increasing volume production and suitable different product.

In the present invention, see also shown in Figure 6, this first 400 and third part 404 can be the rectangular microstrip metal wire, and, this first 400 is connected the side of this third part 404 back to this ground plane 30 back to the side extension of this ground plane 30, this first 400 faces a side of this ground plane 30 towards extending near ground plane 30 and being connected the side of this third part 404 in the face of this ground plane 30, uses to form between this first and second portion to be this trapezoidal second portion 402.And this first 400 can not influence under the whole frequency range of this antenna body, and a corner cut (shown in the 7th figure) or an arc (shown in the 8th figure) are made by this first 400 back to the position in a corner of this short-circuit line 42.Moreover this third part 404 can not influence under the whole frequency range of this antenna body, and this third part 404 is made an arc (shown in the 9th figure) away from an end of this second portion.

Because the shape of first 400 of the present invention and third part 404 is not confined to aforesaid rectangle, second portion 402 is not confined to aforesaid trapezoidal yet, and, the live width of these second portion 402 1 ends and the live width of this first 400 can be unsuitable, and this second portion 402 live width of the live width of end and this third part 400 can be unsuitable yet in addition, therefore, the live width of every third part 404 is bigger than the live width of first 400, and this second portion 402 is towards the shape of expanding gradually and extending away from the direction of this first 400, all belong to can think easily and variation or modification, all can be encompassed in the claim scope of the present invention, for example: see also shown in Figure 10, the both sides of this first 400 expand outwardly definite length extended gradually with one first angle, expand outwardly definite length extended gradually with second angle again, and be connected the both sides of this third part, use between this first and third part, to form and be this bell second portion 402.

In addition, this antenna body 40, short-circuit line 42 and feed-in line 44 can be a little band metal wire, add its simple shape, make this antenna body 40, short-circuit line 42 and feed-in line 44 in the technology of printed circuit board (PCB), to make easily, so, the easier importing volume production of this broadband inversed F type antenna, and then improve the production stability.In addition, the spacing that live width by revising this antenna body 40, short-circuit line 42 and feed-in line 44, length, short-circuit line 42 and feed-in line are 44, and this feed-in line 44 is used the frequency of finely tuning this broadband inversed F type antenna being connected the conditions such as position of this first 400 in the face of these ground plane 30 1 sides.

Figure 11 is according to antenna structure shown in Figure 6, with this antenna body 40, the size indication figure of short-circuit line 42 and feed-in line 44 direct printed wiring board using thems, this first 400 wherein, the width of short-circuit line 42 and feed-in line 44 is all 0.5mm, the total length of this short-circuit line 42 and feed-in line 44 is all 7.6mm, the spacing that this short-circuit line 42 and feed-in line are 44 is 3.6mm, the length of this first 400 is 4.8mm, the width 3.0mm of this third part 404, length 7.1mm, and this short-circuit line 42 is orthogonal thereto mutually with this first 400, and this feed-in line 44 is orthogonal thereto mutually with this first 400, simultaneously, this feed-in line 44 is parallel to each other with short-circuit line 42.So, see also shown in Figure 12ly, the frequency range that this broadband inversed F type antenna measures has been contained about 2128MHz～2830MHz, and about 702MHz, measurement show except frequency range increases, the performance of antenna gain also than traditional inverted F shaped antenna come good.

In the present invention, in order to compensate the inductive of this feed-in line 44, and electric current is uniformly distributed between this antenna body 40, utilize this second portion 402 to finish the coupling framework, reduce the inductive effect of its feed-in, and make the CURRENT DISTRIBUTION trend evenly, and make antenna bandwidth contain bigger scope, simultaneously, structurally the design by this short-circuit line 42 forms inductance, solve power down by this and hold problem, be returned to the purpose that quarter-wave is reached resonance and radiation, as expectedly reaching the effect that increases frequency range, therefore, the present invention does not promptly increase extra match circuit (MatchingCircuit) under the prerequisite that does not change the script board structure of circuit, increase the frequency range of antenna.

The above only is a specific embodiment of the best of the present invention, however feature of the present invention be not limited thereto, anyly be familiar with this skill person in field of the present invention, can think easily and variation or modification, all can be covered by claim scope of the present invention.

Claims

1, a kind of broadband inversed F type antenna, be located on the circuit board, described circuit board is provided with a ground plane in the position near the one lateral edges, and described broadband inversed F type antenna then is provided in a side of between a lateral edges and described ground plane of described circuit board, it is characterized in that, describedly treat inverted F shaped antenna with leniency and comprise:

One antenna body, form by a first, a second portion and a third part, the live width of wherein said first is littler than the width of the live width of third part, described second portion is located between described first and third part, and the live width of described second portion is held expansion gradually to it gradually in addition by the one end, and an end of described second portion and described first join in the face of an end of described third part, and the end in addition of described second portion joins with the end of described third part in the face of described first;

One short-circuit line is located at described first in the face of between a side and this ground plane of described ground plane, and described short-circuit line one end connects described first on the position of described second portion one end, holds in addition then to extend to this ground plane; And

One feed-in line, be located at described first in the face of between a side and this ground plane of described ground plane, one end of described feed-in line is connected described first near on the end of described second portion, and end then extends to the set signal transmitting and receiving loop of described circuit board to this ground plane in addition.

2, broadband inversed F type antenna according to claim 1 is characterized in that, described first and third part can be the rectangular microstrip metal wire.

3, broadband inversed F type antenna according to claim 2, it is characterized in that, described first is connected the side of described third part back to described ground plane back to the side extension of described ground plane, described first is trapezoidal described second portion in the face of a side of described ground plane towards extending near ground plane and be connected the side of described third part in the face of described ground plane, use to form between described first and third part.

4, broadband inversed F type antenna according to claim 3 is characterized in that, a corner cut is made back to the position in a corner of described short-circuit line by described first.

5, broadband inversed F type antenna according to claim 3 is characterized in that, an arc is made back to the position in a corner of described short-circuit line by described first.

6, broadband inversed F type antenna according to claim 3 is characterized in that, described third part is made an arc away from an end of described second portion.

7, broadband inversed F type antenna according to claim 3 is characterized in that, described short-circuit line and described first are orthogonal thereto mutually.

8, broadband inversed F type antenna according to claim 3 is characterized in that, described feed-in line and described first are orthogonal thereto mutually, and simultaneously, described feed-in line and short-circuit line are parallel to each other.

9, broadband inversed F type antenna according to claim 3 is characterized in that, an end line of described second portion live width wide and described first is suitable.

10, broadband inversed F type antenna according to claim 3 is characterized in that, other end line live width wide and described third part of described second portion is suitable.

11, broadband inversed F type antenna according to claim 2, it is characterized in that, the both sides of described first expand outwardly definite length extended gradually with one first angle, expand outwardly definite length extended gradually with second angle again, and be connected the both sides of described third part, use between described first and third part, to form and be bell described second portion.