TWI629836B - Dual-band dipole antenna and electronic system - Google Patents

Abstract

A dual-frequency dipole antenna and an electronic system, the dual-frequency dipole antenna body is a U-shaped or L-shaped first antenna portion, and a square second antenna portion, the first antenna portion having at least one turn The printed radiator is provided with a first electrical connection, and the second antenna is provided with a second electrical connection. When a current source feeds the signal through the first electrical connection portion and the second electrical connection portion, respectively, the first antenna portion and the second antenna portion form a current in the same direction, so that the first antenna portion excites the first The electromagnetic wave of the band and the portion of the second antenna portion adjacent to the first antenna portion cause the second antenna portion to excite the second-band electromagnetic wave that induces an optimized frequency response due to the coupling effect.

Description

Dual-frequency dipole antenna and electronic system

The present invention relates to a dipole antenna and system, and more particularly to a dipole antenna having a small, dual frequency current illuminating body and an electronic system using the same.

In today's fast-changing technology era, the computing power of electronic devices has grown, and the ability of signal processing has become better and better. Especially the evolution of broadband networks and multimedia services has made the transmission rate of electronic devices one of the greatest demands.

Since current electronic products are moving toward light, thin, short, and small designs, in addition to the trend toward miniaturization of various circuit components in electronic products, antennas disposed in electronic products need to support multi-frequency applications. Its size also needs to consider the miniaturized design.

A dipole antenna includes two radiators having two current directions, and the total length of the radiators on both sides is about a half wavelength. Refer to FIG. 1 and FIG. 1 shows the radiation bodies 11, 12 on both sides, and the direction of the current in two directions is formed after the signal is fed through the wire 13. The direction of the arrow indicates the direction of the current; FIG. 2 shows the direction of the symmetrical radiator 21, 22. The antenna, current is fed through the wire 23 into the radiator 21, 22 to form a direction of current in the opposite direction, as indicated by the arrow in the figure. Thus, the radiators on both sides of the dipole antenna form a wider radiation field.

The present invention proposes a dual frequency dipole antenna, and an electronic system using the dual frequency dipole antenna. The dual-frequency dipole antenna body includes a first antenna portion, which may be an L-shaped printed radiator having one turn, or a U-shaped printed radiator having two turns; and a second antenna portion, one side The printed radiation body has four sides, wherein a coupling effect is generated between at least two adjacent sides and the first antenna portion. When the current source is electrically connected to the first electrical connection portion of the first antenna portion and the second electrical connection portion of the second antenna portion via a conductor, respectively, the first antenna portion and the second antenna portion The same signal direction is formed such that a coupling effect occurs between the first antenna portion and the second antenna portion.

In an embodiment, the first electrical connection portion and the second electrical connection portion are disposed at adjacent corresponding positions to facilitate connection of a current end and a ground end of a wire in the same direction.

According to one of the embodiments, the first antenna portion is configured to excite the electromagnetic wave of the first wavelength band; the portion of the second antenna portion adjacent to the first antenna portion causes the second antenna portion to excite an inductively optimized frequency response due to the coupling effect. The second band of electromagnetic waves.

The invention relates to an electronic system, such as a wireless network device, in which the dual frequency dipole antenna described above is employed.

In order to further understand the technology, method and effect of the present invention in order to achieve the intended purpose, reference should be made to the detailed description and drawings of the present invention. The drawings are to be considered in all respects as illustrative and not restrictive

11,12,21,22‧‧‧ radiator

13,23‧‧‧Wire

31‧‧‧First antenna unit

311‧‧‧First electrical connection

301‧‧‧First signal direction

34‧‧‧Conductor structure

32‧‧‧second antenna

321‧‧‧Second electrical connection

302‧‧‧second signal direction

33‧‧‧Wire

313‧‧‧First Radiation Department

314‧‧‧Second Radiation Department

315‧‧‧ Third Radiation Department

41‧‧‧First antenna unit

411‧‧‧First electrical connection

415‧‧‧Conductor structure

413‧‧‧First Radiation Department

414‧‧‧Second Radiation Department

42‧‧‧second antenna unit

421‧‧‧Second electrical connection

43‧‧‧Wire

51‧‧‧First antenna unit

511‧‧‧First electrical connection

515‧‧‧First conductor structure

513‧‧‧First Radiation Department

514‧‧‧Second Radiation Department

52‧‧‧second antenna unit

521‧‧‧Second electrical connection

516‧‧‧Second conductor structure

61‧‧‧First antenna unit

62‧‧‧second antenna

611‧‧‧First electrical connection

621‧‧‧Second electrical connection

L‧‧‧First antenna section radiator length

A‧‧‧second antenna section radiator length

L’‧‧‧first antenna length

A‧‧‧second antenna length

△a1‧‧‧first length

△a2‧‧‧second length

△a3‧‧‧ third length

D1‧‧‧first coupling spacing

D2‧‧‧second coupling spacing

1‧‧‧ first mark

2‧‧‧Second mark

3‧‧‧ third mark

4‧‧‧ fourth mark

5‧‧‧ fifth mark

80‧‧‧ boards

81‧‧‧Double-frequency dipole antenna

84‧‧‧ ground plane

83‧‧‧RF Module

85‧‧‧Baseband module

87‧‧‧ memory unit

1 shows a schematic diagram of a dipole antenna of the prior art; FIG. 2 shows a schematic diagram of a dipole antenna of the prior art; FIG. 3 shows one of the schematic diagrams of an embodiment of the dual-frequency dipole antenna of the present invention; 4 is a second schematic view showing an embodiment of a dual-frequency dipole antenna according to the present invention; FIG. 5 is a third schematic view showing an embodiment of the dual-frequency dipole antenna of the present invention; Figure 7 shows the antenna voltage standing wave ratio of one of the dual-frequency dipole antenna embodiments of the present invention; Figure 8 is a block diagram showing an embodiment of the main circuit components in an electronic system employing the dual-frequency dipole antenna of the present invention.

The disclosure describes a dual-frequency dipole antenna of the present invention and an electronic system using the dual-frequency dipole antenna. One of the main purposes is to propose a printed small-scale dual-frequency dipole antenna that is easy to adjust the frequency band design. In the design of the antenna, According to one of the embodiments, the miniaturized antenna body reduces the antenna area compared to the conventional dipole antenna, for example, a width of about 50-70% or more is smaller than that of the conventional dipole antenna, so that the application can be applied to two frequency bands. Small antennas such as 2G and 5G dual-bands can save a lot of printed antenna material costs and generate more applications for specific electronic systems, such as wireless transmission devices.

The dual-frequency dipole antenna can be adjusted and modified according to the needs of the product to achieve the right application. In particular, the design of the dual-frequency dipole antenna uses independent ground. It does not need to have another lower ground as the general antenna, so the size can be smaller than other types of antennas, so that the antenna can be placed anywhere in the electronic system. It is not limited to the limit that must be connected to the system ground. The signal feeding mode of the dual-frequency dipole antenna can be directly connected to the antenna feeding point by wires, for example, directly soldered to the antenna feeding point by a 50Ω coaxial cable, and the other end of the wire can be arbitrarily extended to the radio frequency (RF) in the electronic system. ) Signal module end. Moreover, according to one embodiment of the dual-frequency dipole antenna, the dual-frequency dipole antenna is formed on the circuit board by printing, which can eliminate the mold cost and assembly cost of the stereo antenna and the deformation of the stereo antenna. risk.

For a dual-frequency dipole antenna embodiment, reference may be made to the schematic diagram of the embodiment shown in FIG. 3. This example is shown as an antenna having a U-shaped (or inverted U-shaped) radiator, which is divided into U-shaped The first antenna portion 31 of the radiator and the second antenna portion 32 close to the square.

The radiator of the dual-frequency dipole antenna has at least one turning. This example shows that the first antenna portion 31 is a printed radiator having two turns, and the first radiating portion 313 and the second radiating portion 314 of the first antenna portion 31 are formed. And the third radiation portion 315. A first electrical connection portion 311 is provided at one end (in this example, the first radiation portion 313 on the left side in the figure, and the first radiation portion 413 in the embodiment of FIG. 4), and the second antenna portion 32 is a square shape. The printed radiator is formed in a printed manner in a region surrounded by the U-shaped structure of the first antenna portion 31, and a second electrical connection is provided at one end of the radiator of the second antenna portion 32 (in this example, the upper left corner) Part 321.

According to an embodiment, when the structure of the first antenna portion 31 is designed, the first antenna portion 31 has two transitions in which the first radiating portion 313, the second radiating portion 314, and the third radiating portion 315 form a U-shaped antenna structure. In terms of scale, the length of the second radiating portion 314 in combination with the third radiating portion 315 needs to be greater than one-half of the overall length of the antenna.

In this example, in order to form the same signal direction on the first antenna portion 31 and the second antenna portion 32, the first electrical connection portion 311 and the second electrical connection portion 321 may be disposed at adjacent corresponding positions. In an embodiment, the first electrical connection portion 311 is a region where the signal of the first antenna portion 31 is fed (provided on the first radiation portion 313), and the second electrical connection portion 321 is set for the next day. The line portion 32 is adjacent to the first radiating portion 313 of the first antenna portion 31 and is a grounded region for connecting a current end and a ground end of the electric wire 33 in the same direction, such as from the left to the right of the electric wire 33. The horizontal direction.

According to an embodiment, the electric wire 33 realizes a conductor which may be a coaxial cable including a central core (current end) through which current is passed and a grounded conductor (grounded end) which are covered, respectively connected to the first electrical connection The portion 311 and the second electrical connection portion 321 . When the current source is electrically connected to the first electrical connection portion 311 and the second electrical connection portion 321 via the electric wire 33, the first signal direction 301 is formed in the first antenna portion 31 and the second antenna portion 32 is formed. The second signal direction 302 is preferably the same signal direction or a nearly parallel signal direction. Therefore, a coupling effect is also generated between the first antenna portion 31 and the second antenna portion 32.

In an embodiment, the first antenna portion 31 is configured to excite an electromagnetic wave in a first wavelength band, such as a band near 2 GHz; and a portion of the second antenna portion 32 adjacent to the first antenna portion 31 is caused by a coupling effect to cause a second antenna. The portion 32 excites a second band of electromagnetic waves that induce an optimized frequency response, such as a band near 5 GHz.

A conductor structure 34 may be provided on the first antenna portion 31 at the structural turning point for the purpose of impedance matching, however the structure of the impedance matching is not limited to this embodiment.

It is noted that the manner in which the wires 33 connected to a current source are connected to the first electrical connection portion 311 of the first antenna portion 31 and the second electrical connection portion 321 of the second antenna portion 32 includes There are welding, brazing, soldering, slashing, riveting, and screwing.

The first antenna portion of the dual-frequency dipole antenna may be an L-shaped printed radiator having only one turn, in addition to the embodiment of the U-shaped radiator described above, as shown in FIG. 4 of the dual-frequency dipole antenna of the present invention. A schematic of an embodiment.

This example shows an L-shaped first antenna portion 41, which can be divided into a first radiating portion 413 and a second radiating portion 414 by using a turning point. The first electrical connecting portion 411 of this example is disposed on the first radiating portion 413. On one end, a transition between the first radiating portion 413 and the second radiating portion 414 may be provided with a conductor structure 415 for adjusting the operating frequency of the antenna. The conductor structure 415 is a conductor in the form of a square. In the scale, in the L-shaped antenna structure, the length of the second radiating portion 414 needs to be greater than one-half of the overall length of the antenna.

In this example, the second antenna portion 42 of the dual-frequency dipole antenna is still a nearly square printed radiation body, and a second electrical connection portion 421 is disposed at a position opposite to the first electrical connection portion 411, which can facilitate the electric wire 43. In the same direction, the current terminal and the ground terminal are respectively connected as a first electrical connection portion 411 of the signal feeding region, and a second electrical connection portion 421 as a ground region.

A coupling effect occurs between the first antenna portion 41 and the second antenna portion 42. When a current source is fed into the antenna through the first electrical connection portion 411 and the second electrical connection portion 421, the first antenna portion is 41 and the same signal direction are formed on the second antenna portion 42 to generate The coupling effect thus induces one of the operating frequencies of the antenna.

In the schematic diagram of the embodiment of the dual-frequency dipole antenna of the present invention shown in FIG. 5, the antenna body still includes a first antenna portion 51, wherein the first radiation portion 513 and the second radiation portion 514 are divided according to the turning point, and the first radiation The first electrical connection portion 511 is disposed on the portion 513, and the second antenna portion 52 is provided with the second electrical connection portion 521.

In particular, the structure for impedance matching in this example includes the first conductor structure 515 disposed at the turn of the first antenna 51, and further includes the second conductor structure 516 formed by the extension of the first radiating portion 513. The conductor structure 516 is a conductor structure that extends downward from the first electrical connection portion 511. In this embodiment, the first electrical connection portion 511 and the second electrical connection portion 521 are still maintained at opposite positions, so that the current can be fed into the first antenna portion 51 and the second antenna portion in the same direction. 52.

It is mentioned here that the embodiment of impedance matching here does not exclude application to a dual-frequency dipole antenna having two turns.

Fig. 6 then shows the design dimensions of the first antenna portion 61 and the second antenna portion 62 in the dual-frequency dipole antenna of the present invention, and a dual-frequency dipole antenna having one turn is taken as an example.

In the design of the dual-frequency dipole antenna, the first electrical connection portion 611 on the first antenna portion 61 and the second electrical connection portion 621 on the second antenna portion 62 are maintained at corresponding positions in the same direction when the wires are connected. The radiator of the first antenna portion 61 mainly senses the signal of the first wavelength band, and the radiator of the second antenna portion 62 senses the signal of the second wavelength band, and between the first antenna portion 61 and the second antenna portion 62 The same current direction coupling effect excites the second band of electromagnetic waves that optimize the frequency response.

According to the schematic diagram of the embodiment, the first antenna portion radiator length L and the second antenna portion radiator body length A are displayed, and the design may have a proportional relationship.

For example, the first antenna portion length L' (up to L) and the second antenna portion length a (up to A), and the second antenna portion length a change includes a + first length Δa1, a + second length Δa2 With a + third length Δa3.

The first antenna portion length L' should have a The length of the electromagnetic wavelength is proportional to the relationship; for the same reason, the length of the second antenna portion a should also have a certain length for the purpose of sensing the electromagnetic wave of the second band, and the length of the second antenna portion a should be considered, and the first antenna The second band electromagnetic wave induced by the coupling effect between the portion 61 and the second antenna portion 62 (taking into account the first coupling pitch d1 and the second coupling pitch d2).

The first antenna portion length L' has a ratio (L'/a) to the second antenna portion length a. And the ratio (L'/a) changes as the length of the second antenna portion 62 changes, and the ratio (L'/a) has a maximum value (max), and the maximum value is more standardized within a specific range. The dual-frequency dipole antenna can operate under specific electromagnetic waves according to the requirements of the electronic system.

Figure 7 then shows the antenna Standing Wave Ratio (VSWR) of one of the dual-frequency dipole antenna embodiments of the present invention.

In the figure, the horizontal axis represents the frequency (GHz), and the vertical axis represents the reflection loss (dB, return loss). From the experimental data, the reflection loss value of the dual-frequency dipole antenna in each frequency band can obtain a suitable operating frequency band. The first mark 1 of the curve indicates a reflection loss value of 1.8716 at 2.4 GHz; the second mark 2 indicates a reflection loss value of 1.6695 at 2.45 GHz; and the third mark 3 indicates a reflection loss value of 1.7719 at 2.5 GHz, thus dual frequency The dipole antenna can be used in the operating frequency range of 2400MHz~2500MHz, and is applicable to the IEEE802.11b/g wireless communication version. Moreover, the fourth mark 4 indicates a reflection loss value of 1.6173 at 4.9 GHz; the fifth mark 5 indicates a reflection loss value of 1.3467 at 5.85 GHz, so that the dual-frequency dipole antenna can be applied with an operating frequency of 4900 MHz to 5850 MHz, which is applicable to IEEE802. 11 ac wireless communication version. Thus, the dual-frequency dipole antenna of the present invention achieves the purpose of dual-frequency application.

The invention also relates to an electronic system, such as a wireless network device, wherein the dual-frequency dipole antenna described above is employed, such as the main circuit components of the electronic system shown in FIG. A dual-frequency dipole antenna 81 is disposed on the circuit board 80 of the wireless network device, and the related circuit component includes a ground plane 84. The main components of the circuit board 80 include a radio frequency module 83 and a baseband module ( Bass-band module 85 and memory unit 87.

The RF module 83 is electrically connected to the dual-frequency dipole antenna 81 for converting the received antenna signal or converting the transmitted electromagnetic wave signal. The signal of the dual-frequency dipole antenna 81 is received by the radio frequency module 83 and processed by the baseband module 85, stored in the memory unit 87, and can provide circuitry inside the electronic system; or the signal generated by the electronic system is transmitted through the fundamental frequency mode. The group 85 is processed, converted into electromagnetic waves by the radio frequency module 83, and transmitted through the dual-frequency dipole antenna 81.

Therefore, the disclosure is described as a printed dual-frequency dipole antenna, wherein the current directions of the two antenna radiators are in the same direction according to the design of the signal feeding position, which is different from the two branches of the conventional dipole antenna. Reverse current direction, and the antenna is designed independently, without the lower end of the general antenna, and achieves the benefits of miniaturization and wide application.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

Claims (16)

A dual-frequency dipole antenna includes: a first antenna portion, which is a printing radiator having at least one turning, and a first electrical connecting portion; and a second antenna portion, which is a square printed radiator. a second electrical connection portion; wherein a current source is electrically connected to the first electrical connection portion and the second electrical connection portion via a conductor, respectively, to the first antenna portion and the second antenna Forming the same signal direction such that a coupling effect occurs between the first antenna portion and at least two adjacent sides of the second antenna portion; wherein the at least one corner of the first antenna portion is printed The length of the radiator after a turn is greater than one-half of the overall length of the first antenna portion. The dual-frequency dipole antenna according to claim 1, wherein the first antenna portion includes only one turn to form an L-shaped radiator. The dual-frequency dipole antenna according to claim 2, wherein the L-shaped radiator includes a first radiating portion and a second radiating portion to form a turn of the first antenna portion. The dual-frequency dipole antenna according to claim 3, wherein the length of the second radiating portion needs to be greater than one-half of the entire length of the first antenna portion. The dual-frequency dipole antenna according to claim 1, wherein the first antenna portion includes two turns to form a U-shaped radiator. The dual-frequency dipole antenna according to claim 5, wherein the U-shaped radiator comprises a first radiating portion, a second radiating portion and a third radiating portion, and the two corners of the first antenna portion are formed. The dual-frequency dipole antenna according to claim 6, wherein the length of the second radiating portion in combination with the third radiating portion is greater than one-half of the entire length of the first antenna portion. The dual-frequency dipole antenna according to any one of claims 1 to 7, wherein the first electrical connection portion is disposed on the first radiating portion of the first antenna portion, and is a region into which a signal is fed; The second electrical connection portion is disposed on the second antenna portion adjacent to the first antenna One side of the first radiating portion of the portion is a grounded region. The dual-frequency dipole antenna according to claim 8, wherein the first antenna portion is configured to excite an electromagnetic wave of a first wavelength band; the portion of the second antenna portion adjacent to the first antenna portion is caused by the coupling effect The second antenna portion excites a second band of electromagnetic waves that induce an optimized frequency response. The dual-frequency dipole antenna according to claim 9, wherein the first electrical connection portion and the second electrical connection portion are disposed at adjacent corresponding positions to facilitate connection of a current in the same direction of a wire. End and a ground. The dual-frequency dipole antenna according to claim 10, wherein the first antenna portion is provided with a conductor structure for adjusting antenna impedance matching. The dual-frequency dipole antenna of claim 11, wherein the conductor structure comprises a structure in which the first radiating portion extends. The dual-frequency dipole antenna of claim 11, wherein the conductor structure comprises a structure at a turn between the first radiating portion and the second radiating portion of the first antenna portion. An electronic system having a dual-frequency dipole antenna includes: a first antenna portion, which is a printed radiator having at least one turn, and a first electrical connection portion; a second day The wire portion is a square printed radiator, and is provided with a second electrical connection portion; wherein a current source is electrically connected to the first electrical connection portion and the second electrical connection portion via a conductor to respectively The first antenna portion and the second antenna portion form the same signal direction, such that a coupling effect occurs between the first antenna portion and at least two adjacent sides of the second antenna portion; wherein the first antenna portion The length of the at least one turned-off printing radiator of an antenna portion after a turn is greater than one-half of the overall length of the first antenna portion. The electronic system of claim 14, wherein the first antenna portion of the dual-frequency dipole antenna comprises a first radiating portion and a second radiating portion forming an L-shaped radiator And forming a turn; the length of the second radiating portion needs to be greater than one-half of the overall length of the first antenna portion. The electronic system of claim 14, wherein the first antenna portion of the dual-frequency dipole antenna comprises a first radiating portion, a second radiating portion and a third radiating portion forming a U-shaped radiator. And forming two transitions; the length of the second radiating portion combined with the third radiating portion needs to be greater than one-half of the entire length of the first antenna portion.