TWI599104B - Multi-frequency antenna - Google Patents

Description

Multi-frequency antenna

This creation is about an antenna, especially with regard to a multi-band antenna.

The rapid development of wireless transmission brings a variety of products and technologies for multi-band transmission, so that many new products have wireless transmission performance to meet the needs of consumers. The antenna is an element used to transmit and receive electromagnetic wave energy in a wireless transmission system. If there is no antenna, the wireless transmission system will not be able to transmit and receive signals. The selection of an appropriate antenna not only helps to match the appearance of the product and enhances the transmission characteristics, but also further reduces the product cost.

With the development of wireless communication systems, antennas in handheld mobile devices can operate in several wireless communication systems, such as GSM, UMTS, LTE, WiFi, Bluetooth, and WiMax. Therefore, antennas of various wireless communication system operating frequency bands are applied. Inside the handheld mobile device. However, the design of the handheld mobile device is required to be thin and light and the appropriate size. The increase in the number of antennas in the handheld mobile device will result in an increase in the weight, appearance and cost of the antenna. Therefore, there is a need to design one that can operate differently. Multi-frequency antenna for wireless communication systems.

In view of this, the main purpose of this creation is to provide a multi-frequency antenna with the function of operating in multiple frequency bands.

In order to achieve the above object, the technical means adopted by the present invention is that the multi-frequency antenna comprises: a substrate; and a radiator formed on a surface of the substrate and comprising: a grounding unit having a grounding point; a first radiating unit is located at one side of the grounding unit, and the first radiating unit comprises a body, a connecting portion and a connecting portion connected between the body and the beak portion, the beak portion having opposite sides a first end and a second end, the first end of the beak is connected to the body through the connecting portion, the width of the connecting portion is tapered from the first end of the beak to the body A side of the body adjacent to the grounding unit includes a first oblique side and a second oblique side opposite to each other, wherein the first oblique side and the second oblique side form a convex cone, the first oblique side and the first oblique side The area between the second oblique sides includes a signal feeding point; a second radiating unit is located at one side of the first radiating unit, such that the body of the first radiating unit is located at the second radiating unit and the ground Between the units, the second radiating unit and the first radiating unit have a coupling gap; a third radiating unit is connected to the second radiating unit; and a microstrip line unit includes a first end and a opposite end a second end, the first end is connected to the second radiating unit and The first end of the radiating unit is connected to the grounding unit; the first radiating unit is configured to resonate the high frequency band, and the first radiating element, the coupling gap, the second radiating element and the microstrip line unit are used for resonant low frequency In the frequency band, the third radiating element is used to resonate the intermediate frequency band.

The creation system utilizes the layout configuration of the first radiation unit, the second radiation unit and the third radiation unit to achieve the effect of multi-band resonance, and can operate in different wireless communication systems. Specific embodiments of the present work are detailed below.

11‧‧‧First Radiation Unit

111‧‧‧Ontology

112‧‧‧Deformation

113‧‧‧Connecting Department

114‧‧‧First bevel

115‧‧‧second bevel

116‧‧‧ openings

12‧‧‧second radiation unit

121‧‧‧ Short side

122‧‧‧ long side

13‧‧‧ Third radiating element

131‧‧‧First Ontology

132‧‧‧Second ontology

133‧‧‧Connecting Department

14‧‧‧Microstrip line unit

141‧‧‧ first end

142‧‧‧ second end

143‧‧‧Bend

15‧‧‧Conducting unit

151‧‧‧Electrical conductor

152‧‧‧ Grounding conductor

16‧‧‧ Grounding unit

161‧‧‧ Straight edge

17‧‧‧Substrate

20‧‧‧Coupling gap

Figure 1 is a perspective view of a preferred embodiment of the present invention.

Figure 2 is a schematic plan view showing a preferred embodiment of the present invention for connecting a conductive unit.

Figure 3 is a graph showing the return loss characteristic of the preferred embodiment of the present invention.

Figure 4 is a partially enlarged schematic view of the preferred embodiment of the present invention.

Referring to FIG. 1 and FIG. 2, a preferred embodiment of the present multi-frequency antenna includes a substrate 17 and a radiator formed on at least one surface of the substrate 17. The substrate 17 may be a printed circuit board made of BT (Bismaleimide) resin or a glass fiber reinforced epoxy resin (FR4), or a flexible sheet substrate made of polyimide (Polyimide) ( Flexible film substrate), or a substrate with a circuit device to reduce the space occupied by the present multi-frequency antenna. The radiator may be a member made of a conductive metal foil, or may be formed on the surface of the substrate 17 by using printing or etching techniques; the radiator includes a first radiation unit 11, a second radiation unit 12, and a third radiation. The unit 13, a microstrip line unit 14 and a grounding unit 16, wherein the grounding unit 16 is formed on the side of the substrate 17, and the first radiating unit 11, the second radiating unit 12, the third radiating unit 13 and the microstrip The wire unit 14 is formed on the other side of the substrate 17 with respect to the grounding unit 16; the second radiating element 12, the third radiating element 13, the microstrip line unit 14, and the grounding unit 16 may be integrally formed.

The grounding unit 16 can be a full-face structure and includes a straight edge 161, and any position in the grounding unit 16 can serve as a grounding point G.

The first radiating unit 11 is located at one side of the grounding unit 16 and includes a body 111, a weir portion 112 and a connecting portion 113 connected between the body 111 and the weir portion 112. The weir portion 112 has The first end and the second end of the opposite end are connected to the body 111 through the connecting portion 113. The width of the connecting portion 113 is from the first end of the beak 112 The direction of the body 111 is tapered. The width of the connection between the connecting portion 113 and the body 111 can be the same as the width of the body 111. The side of the body 111 adjacent to the grounding unit 16 includes a first oblique side opposite to the oblique direction. 114 and a second oblique side 115, the first oblique side 114 and the second oblique side 115 form a convex cone, and the body 111 of the first radiating unit 11 (preferably the first oblique side 114 and the first An arbitrary position of the area between the two oblique sides 115 includes a signal feed point F. Referring to FIG. 2, the impedance matching of the input impedance of the antenna can be adjusted through the angle θ between the first oblique side 114 and the straight side 161 of the grounding unit 16, as follows:

In the above formulas (1) to (4), Z _{in is} the input impedance of the authored multi-frequency antenna at the feeding end (ie, the aforementioned signal feeding point F and the grounding point G), and Z _{0 is the} original multi-frequency antenna. Characteristic impedance; l is the length of the first oblique side 114 or the second oblique side 115; K = 2 π / λ , λ is the signal wavelength; P _n (cos θ ₀ ) is the n-order Legendre polynomial, ; ξ _n ( kl ) is a helper function; ( kl ) is a second-order ball Hankel function.

The second radiating unit 12 is located at one side of the first radiating unit 11 such that the body 111 of the first radiating unit 11 is located between the second radiating unit 12 and the grounding unit 16, and the second radiating unit 12 is a long strip-like structure having a uniform or uneven width. The embodiment shown in FIGS. 1 and 2 is exemplified by the fact that the second radiating element 12 has a uniform (ie, the same) width. The second radiating element 12 includes a short side 121 and a long side 122 adjacent to the second end of the beak 112 of the first radiating element 11 and outside the opening 116 of the domed portion 112. The second end of the second radiating element 12 is not connected to the second end of the second radiating unit 12, and the first end of the first radiating portion 11 is adjacent to the first end of the first radiating portion 11. There is a long side 122 between the first radiating element 11 and the first radiating element 11 The coupling gap 20, the second radiating element 12 and the first radiating element 11 transmit energy through the coupling gap 20 in a coupled manner.

The third radiating element 13 may be a polygonal structure having a uniform or uneven width, a straight strip structure or a curved structure. The preferred embodiment of the present invention is a curved structure, which includes a first body 131 disposed adjacent to each other. A second body 132 is connected to the second body 132 through a connecting portion 133 , and the first body 131 is in contact with the second radiating unit 12 .

The microstrip line unit 14 includes a first end 141 and a second end 142. The first end 141 is connected to the junction of the second radiating unit 12 and the third radiating unit 13. The second end 142 is connected. The grounding unit 16. At least one bent portion 143 may be included between the first end 141 and the second end 142. By adjusting the length of the microstrip line unit 14, the low-band resonance frequency point f _{r 1 of the} present multi-frequency antenna can be adjusted as follows: f _{r 1} = C / L ₁ (5)

In the above formula (5), C is the speed of light, and L ₁ is a boundary from the first oblique side 114 and the second oblique side 115 of the first radiating element 11, the coupling gap 20, the second radiating element 12, and the microstrip A resonant low frequency path length formed by line unit 14 to ground unit 16.

Referring to FIG. 2, the present multi-frequency antenna can be connected to a conductive unit 15 having a conductive body 151 and a grounding conductor 152. The conductive body 151 is electrically connected to the feeding point F, and the grounding conductor is connected. The 152 series is electrically connected to the grounding point G. In this embodiment, the conductive unit 15 can be a coaxial transmission line, and the conductor 151 is equivalent to the center conductor of the coaxial transmission line, and the ground conductor 152 is equivalent to the ground conductor of the coaxial transmission line. In addition, the connection manner of the conductive unit 15 and the multi-band antenna 1 can be changed according to the shape of the applied product, and only needs to be electrically connected to the feeding point F according to the electrical conductor 151, and the grounding conductor 152 and the grounding point G are electrically connected. The principle of sexual connection can be.

Please refer to FIG. 3, which is a return loss characteristic diagram of the preferred embodiment of the present invention. In the present creation, the first radiating unit 11 is configured to resonate a high frequency band, and the high frequency band operates in a range of about 2 GHz to 6 GHz; the third radiating element 13 is used to resonate an intermediate frequency band, and the intermediate frequency is The segment operation range is between 1.07 GHz and 2 GHz, and by adjusting the length of the third radiating element 13, an optimum intermediate frequency band resonance frequency point f _{r 2} can be obtained as follows: f _{r 2} = C / L ₂ ( 6)

In the above formula (6), C is the speed of light, L ₂ is the boundary between the first oblique side 114 and the second oblique side 115 of the first radiating element 11, the coupling gap 20, and the second radiating element 12 to the third A resonant intermediate frequency path length formed by the end of the second body 132 of the radiating element 13 (path X1-X2-X3-X4-X6 as shown in FIG. 4).

As shown in the formula (5), since L ₁ is a resonant low-frequency path length formed from the first radiating element 11, the coupling gap 20, the second radiating element 12, the microstrip line unit 14 to the grounding unit 16 (as shown in the figure) The path X1-X2-X3-X4-X5 shown in FIG. 4 is in a resonant low frequency band, the low frequency band operating range is about 0.75 GHz, and the coupling gap 20 between the first radiating element 11 and the second radiating element 12 is The length of the microstrip line unit 14 reaches the current path length required to shorten the low frequency, thereby effectively reducing the volume of the present multi-frequency antenna. As mentioned above, this creation can achieve the use of multi-frequency operation in the low frequency band, the intermediate frequency band and the high frequency band.

In summary, the multi-frequency antenna according to the present invention utilizes the first radiating element 11, the second radiating element 12, and the third radiating element 13 to achieve the effect of multi-band resonance. In addition, by using the path of the first radiating element 11, the coupling gap 20, the second radiating element 12 and the second end 142 of the microstrip line unit 14 to ground, the frequency of the microstrip line unit 14 can be appropriately adjusted to make the low frequency The frequency band is optimized. Adjusting the length of the third radiating element 13 can also optimize the frequency band of the intermediate frequency for 1 GHz and 1.71 to 2.7 GHz.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Although the present invention has been disclosed above in the preferred embodiment, it is not intended to limit the present invention, and any technique familiar to the art. Personnel, without departing from the scope of this creative technical solution, Equivalent embodiments of the above-described embodiments may be modified or modified as equivalent changes, and any simple modifications and equivalent changes made to the above embodiments in accordance with the technical essence of the present invention are not disclosed. Modifications are still within the scope of this creative technical solution.

11‧‧‧First Radiation Unit

111‧‧‧Ontology

112‧‧‧Deformation

113‧‧‧Connecting Department

114‧‧‧First bevel

115‧‧‧second bevel

116‧‧‧ openings

12‧‧‧second radiation unit

121‧‧‧ Short side

122‧‧‧ long side

13‧‧‧ Third radiating element

131‧‧‧First Ontology

132‧‧‧Second ontology

133‧‧‧Connecting Department

14‧‧‧Microstrip line unit

141‧‧‧ first end

142‧‧‧ second end

143‧‧‧Bend

16‧‧‧ Grounding unit

161‧‧‧ Straight edge

17‧‧‧Substrate

20‧‧‧Coupling gap

Claims (6)

A multi-frequency antenna comprising: a substrate; and a radiator formed on a surface of the substrate and comprising: a grounding unit having a grounding point; and a first radiating unit on a side of the grounding unit The first radiating unit comprises a body, a ridge portion and a connecting portion connected between the body and the ridge portion, the dam portion having an opposite first end and a second end, the ridge portion The first end is connected to the body through the connecting portion, the width of the connecting portion is tapered from the first end of the beak portion toward the main body, and the side of the main body adjacent to the grounding unit comprises an oblique direction opposite a first oblique side and a second oblique side, the first oblique side and the second oblique side forming a convex cone, and the area between the first oblique side and the second oblique side comprises a signal feeding a second radiation unit located on one side of the first radiation unit, such that the body of the first radiation unit is located between the second radiation unit and the ground unit, the second radiation unit and the first radiation There is a coupling gap between the units; a third radiation single Connecting the second radiating unit; a microstrip line unit comprising an opposite first end and a second end, wherein the first end is connected to the junction of the second radiating unit and the third radiating unit, the second The first radiating unit is configured to resonate the high frequency band, the first radiating element, the coupling gap, the second radiating element and the microstrip line unit are used to resonate the low frequency band, and the third radiating unit is used for resonance IF band. The multi-frequency antenna according to claim 1, wherein the second radiating element is a long strip structure, the second radiating unit includes a short side and a long side, and the short side of the second radiating unit is adjacent to the a second end of the beak of the first radiating element and located outside the opening of one of the beaks without being connected to the beak The second end, the long side of the second radiating element is adjacent to the first radiating unit and has the coupling gap between the first radiating element. The multi-frequency antenna of claim 1, the third radiating unit includes a first body and a second body disposed adjacent to each other, the first body and the second body are connected through a connecting portion, and the first The body is in contact with the second radiating element. The multi-frequency antenna according to claim 1, wherein the microstrip line unit includes at least one bent portion between the first end and the second end. The multi-frequency antenna according to claim 1, wherein the connection between the connecting portion of the first radiating unit and the body is the same as the width of the body. The multi-frequency antenna of claim 1, wherein: the width of the connection between the connection portion of the first radiation unit and the body is the same as the width of the body; the second radiation unit is a long strip structure, so that the first The second radiating unit comprises a short side and a long side, and the short side of the second radiating unit is adjacent to the second end of the beak of the first radiating unit and is located outside the opening of the beak and is not connected a second end of the second radiating unit, the long side of the second radiating unit is adjacent to the first radiating unit and has the coupling gap between the first radiating unit; the third radiating unit includes an adjacent one a body and a second body, the first body and the second body are connected through a connecting portion, and the first body is in contact with the second radiating unit; the first end and the second end of the microstrip line unit At least one bend is included between them.