TWI515973B - A multiband monopole antenna for wwan/lte operation - Google Patents

Description

Multi-band monopole antenna for WWAN/LTE

The present invention relates to an antenna device, and more particularly to a multi-band monopole antenna for WWAN/LTE.

With the increasing popularity of wireless communication, today's wireless transmission interface has gradually evolved from the third generation (3G) mobile communication system to the fourth generation (4G) mobile communication system, and Long Term Evolution (LTE) is the fourth generation. One of the communication protocols for mobile communication systems.

Compared with the Wireless Wide Area Network (WWAN), the Long Term Evolution (LTE) technology has a higher amount of data transmission and is therefore more practical. The operating bandwidth of LTE can be divided into three types: the operating bandwidth of LTE 700 is between 698 and 787 MHz, the operating bandwidth of LTE 2300 is between 2300 and 2400 MHz, and the operating bandwidth of LTE 2500 is between 2,500. Between 2690MHz, since LTE is regarded as the mainstream specification for next-generation mobile communication devices, quite a number of prior technologies have been developed. For example, KLWong et al. have recently proposed in Microwave and Optical Technology Letters. "WWAN/LTE printed loop tablet computer antenna and its body SAR analysis", "Bandwidth enhancement of small-size planar tablet computer antenna using a parallel-resonant spiral slit", "Bandwidth enhancement of small-Size internal WWAN laptop computer antenna using a resonant open slot embedded in the ground plane In the literature, an antenna device suitable for the WWAN/LTE specification is proposed.

The above-mentioned technical methods proposed by KL Wong et al. are mainly based on inverted L-type microstrip lines. However, from the aspects of antenna area, Radiation Efficiency or coverage band, The radiation efficiency of the technology is mostly between 60% and 80%, or it does not effectively cover the overall frequency band of LTE, or the antenna area is not small enough, and there is still considerable room for improvement, so that it can be applied to more applications. There is considerable room for improvement.

Therefore, the object of the present invention is to provide a multi-band monopole antenna for WWAN/LTE, which is suitable for electrically connecting with a grounding unit of an electronic device to transmit and receive an antenna signal, comprising: a substrate; a first resonance The unit is disposed on the substrate and electrically connected to the grounding unit, and is configured to feed the antenna signal; a second resonating unit is disposed on the substrate and electrically connected to the grounding unit, and includes: a first line segment, Parallel to and spaced apart from the first resonating unit; a second line segment, one end of which is electrically connected to one end of the first line segment and disposed perpendicular to the first line segment; a third line segment, and the second line segment The line segments are parallel and spaced apart; a fourth line segment is electrically connected to one end of the third line segment and perpendicular to the third line segment; a fifth line segment is parallel to the second line segment and the third line segment And phase a sixth line segment, one end is electrically connected to one end of the fifth line segment, and is disposed perpendicular to the fifth line segment; and a connecting portion, and one end of the second line segment, the third line segment, and the fifth line segment Electrically connecting; and wherein the first resonant unit receives the antenna signal, resonates with the first line segment, and passes through the first line segment, the second line segment, the connecting portion, the third line segment, and the fourth line segment Radiating the antenna signal; and the first resonating unit resonates with the sixth line segment and radiates the antenna via the sixth line segment, the fifth line segment, the connecting portion, the second line segment, and the first line segment signal.

Therefore, the effect of the present invention is that compared with the prior art, the volume is relatively small, the radiation efficiency is high, and all the frequency bands of the WWAN/LTE can be completely covered, so that it can be applied to the antenna signals of the WWAN/LTE specifications.

The details of the related patents and the technical contents of the present invention will be apparent from the following detailed description of a preferred embodiment of the drawings.

Referring to FIG. 1, a preferred embodiment of the present invention is adapted to be electrically connected to an electronic device for transmitting and receiving an antenna signal, comprising: a substrate 5, a first resonating unit 1, a second resonating unit 2, and a ground. The unit 9, wherein the first resonating unit 1 and the second resonating unit 2 are disposed on the same surface of the substrate 5, and preferably, the substrate 5 is an FR4 base having a thickness of 0.8 mm. board.

It should be noted that the grounding unit 9 includes an L-shaped slit 91, and the slit has a width of 0.2 mm, a length L1 of 19 mm, and another length L2 of 47 mm. The slit 91 can be used to increase the low frequency bandwidth. Preferably, the grounding unit 9 can be shared with the electronic device.

The first resonating unit 1 includes a feeding portion 11 and a first resonating portion 12, the first resonating portion 12 is a rectangle, and the feeding portion 11 is electrically connected to one end of the first resonating portion 12 and protrudes The first resonating portion 12 is electrically connected to the ground unit 9.

The second resonating unit 2 includes a first line segment 21, a second line segment 22, a third line segment 23, a fourth line segment 24, a fifth line segment 25, a sixth line segment 26, and a connecting portion 27; The connecting portion 27 has a first connecting portion 271 , a second connecting portion 272 , and a third connecting portion 273 , and the first line segment 21 is electrically connected to the grounding unit 9 .

The first line segment 21 is parallel to and spaced apart from the feeding portion 11, and one end thereof is electrically connected to the second line segment 22 in a vertical manner and has an inverted L shape. Similarly, the third line segment 23 and the fourth line segment are similarly 24 is electrically connected in a vertical manner and is in an inverted L shape. The fifth line segment 25 and the sixth line segment 26 are electrically connected in a vertical manner and also have an inverted L shape, and the second line segment 22, the third line segment 23, and the fifth line segment are 25 is arranged in parallel and in a spaced manner, and the first line segment 21, the fourth line segment 24, and the sixth line segment 26 are arranged in parallel and at intervals.

The connecting portion 27 is electrically connected to the second line segment 22, the third line segment 23, and the fifth line segment 25, respectively, and the second line segment 22 and the fifth line segment 25 are respectively The second connecting section 272 is electrically connected to the second connecting section 272, and the third connecting section 273 is electrically connected to the first connecting section 271, and the third connecting section 273 is used for connecting the first connecting section 271 with The second connecting section 272 is disposed in parallel and spaced apart from the second connecting section 272.

It should be noted that, in the preferred embodiment, the first resonating unit 1 is interposed between the first line segment 21 and the sixth line segment 26. Therefore, the preferred embodiment includes an inverted L-shaped single Inverted-L monopole strip and a parasitic shorted strip.

Therefore, after the antenna signal is input by the feeding portion 11, the antenna signal is radiated into the air via the parasitic short-circuit strip line and the inverted L-type monopolar strip line transmission path: according to the inverted L-type unipolar strip Transmission path of the line: after the antenna signal is fed by the feed portion 11 (node A), it is coupled to the second line unit 21 via the first line segment 21 (node B), and then the antenna signal passes through the line The first line segment 21 is transmitted to the joint portion 27 (node C), and then transmitted to the third line segment 23 (node D) via the first joint segment 271, and finally to the fourth line segment 24 (node E). Radiating out, that is, one of the antenna signals is transmitted in the order of ABCDE; or

According to the transmission path of the parasitic short-circuiting line: the antenna signal is fed by the feeding portion 11 (node A), and then transmitted to the first resonating portion 12 (node H), and then the first resonating portion 12 and the first The six line segment 26 is coupled for transmission to the second resonating unit 2 (node G), and then transmitted via the fifth line segment 25 And sent to the second connecting segment 272 (node F), and finally transmitted to the first line segment 21 (node B) via the second line segment 22 to radiate, that is, the other transmission path of the antenna signal is The node order is AHFFB.

In fact, the preferred embodiment of the preferred embodiment has a small size of 45 x 15 mm ² , i.e., a width W of 45 mm and a length L of 15 mm.

Preferably, the preferred embodiment is applicable to a tablet computer, and the grounding unit 9 is a grounding unit of the tablet device. For example, the preferred embodiment is applied to a 7-inch tablet. When the computer device is mounted, the size of the grounding unit 9 is 195×122 mm ² . Referring to FIG. 2 , the analog waveform and the actual measurement waveform of the preferred embodiment have little error, and have a bandwidth of 255 MHz at a low frequency (690). ~965MHz), and has a bandwidth of 980MHz (1710~2690MHz) at high frequencies. Therefore, the preferred embodiment can cover LTE700, LTE2300, LTE2500, and GSM850 (824~894MHz), GSM900 (870~935MHz). ), DCS1800 (1710~1879MHz), PCS1900 (1850~1989MHz) and other frequency bands, so it can be used to transmit and receive antenna signals of WWAN/LTE specifications.

Referring to FIG. 3, the preferred embodiment and a technique having only a transmission path of an inverted L-type monopole strip line (hereinafter referred to as prior art A), and a technique having only a transmission path of a parasitic short-circuit strip line (hereinafter referred to as In comparison with the prior art B), it can be clearly seen that the preferred embodiment can excite another resonant mode (about 720 MHz), so the preferred embodiment is compared to prior art A, prior art B. It is more suitable for transmitting and receiving antenna signals of WWAN/LTE specifications.

Referring to FIG. 4 and FIG. 5 together, in the low frequency and high frequency, the radiation efficiency of the preferred embodiment can be maintained between 88% and 90%, and the antenna gain can be maintained between 2.5 and 3 dBi. The performance of the preferred embodiment can be increased by more than 50% over the prior art.

In summary, the volume of the present invention is about 45×15×0.8 mm ³ , so the volume is relatively small compared to the antenna device of the technical method proposed by KL Wong et al. In addition, the radiation efficiency of the present invention is relatively large. It can be maintained at 80%~85% or above. Therefore, it is better than the previous technology. At the same time, most importantly, the low frequency band and high frequency band of the present invention can completely cover LTE700, LTE2300, LTE2500, GSM850, The frequency bands such as GSM900, DCS1800, and PCS1900 are fully applicable to the antenna signals of the WWAN/LTE specifications. It is indeed possible to achieve the object of the invention.

The above is only the preferred embodiment of the present invention, and the scope of the invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are All remain within the scope of the invention patent.

1‧‧‧First Resonance Unit

11‧‧‧Feeding Department

12‧‧‧First Resonance Department

2‧‧‧Second Resonance Unit

21‧‧‧First line

22‧‧‧second line

23‧‧‧ third line segment

24‧‧‧ fourth line

25‧‧‧ fifth line

26‧‧‧ sixth line

27‧‧‧Connecting Department

271‧‧‧ first link

272‧‧‧Second link

273‧‧‧3rd link

5‧‧‧Substrate

9‧‧‧ Grounding unit

91‧‧‧ slit

1 is a circuit diagram of a preferred embodiment of the present invention; FIG. 2 is a reflection loss waveform diagram of the present invention; FIG. 3 is a comparison diagram of reflection loss of the present invention and the prior art; and FIG. 4 is an antenna for operating at a low frequency according to the present invention; Waveform of gain and radiation efficiency; and Figure 5 is the antenna gain and radiation efficiency of the present invention operating at high frequencies Waveform diagram.

1‧‧‧First Resonance Unit

11‧‧‧Feeding Department

12‧‧‧First Resonance Department

2‧‧‧Second Resonance Unit

21‧‧‧First line

22‧‧‧second line

23‧‧‧ third line segment

24‧‧‧ fourth line

25‧‧‧ fifth line

26‧‧‧ sixth line

27‧‧‧Connecting Department

271‧‧‧ first link

272‧‧‧Second link

273‧‧‧3rd link

5‧‧‧Substrate

9‧‧‧ Grounding unit

91‧‧‧ slit

Claims (7)

A multi-band monopole antenna for WWAN/LTE, suitable for transmitting and receiving an antenna signal with an electronic device, comprising: a substrate; a first resonating unit disposed on the substrate and configured to feed the antenna signal a second resonating unit disposed on the substrate, comprising: a first line segment parallel to and spaced apart from the first resonating unit; and a second line segment, one end electrically connected to one end of the first line segment And being disposed in a vertical direction with the first line segment; a third line segment parallel to and spaced apart from the second line segment; a fourth line segment, one end electrically connected to one end of the third line segment, and the third line The segment is disposed in a vertical direction; a fifth segment is parallel to and spaced apart from the second segment and the third segment; and a sixth segment is electrically connected to one end of the fifth segment and to the fifth segment a vertical direction; and a connecting portion electrically connected to one end of the second line segment, the third line segment, and the fifth line segment; and wherein the first resonant unit receives the antenna signal, resonates with the first line segment and The first line The second segment, the connecting portion The third line segment and the fourth line segment radiate the antenna signal; and the first resonating unit resonates with the sixth line segment and passes through the sixth line segment, the fifth line segment, the connecting portion, the second line segment, and The first line segment radiates the antenna signal. The multi-band monopole antenna for WWAN/LTE according to claim 1, wherein the first resonating unit comprises: a feeding portion for feeding the antenna signal, and a feeding portion a first resonating portion connected to resonate with the sixth line segment. The multi-band monopole antenna for WWAN/LTE according to claim 1 further includes a grounding unit electrically connected to the first line segment and the first resonating unit. The multi-band monopole antenna for WWAN/LTE according to claim 3, wherein the grounding unit is disposed on the electronic device. The multi-band monopole antenna for WWAN/LTE according to claim 3, wherein the grounding unit comprises a slot. The multi-band monopole antenna applied to WWAN/LTE according to claim 5, wherein the slot is an L-shape. The multi-band monopole antenna for WWAN/LTE according to claim 1, wherein the connecting portion includes a first connecting segment electrically connected to the third segment, and a second segment, a second connecting section electrically connected to the five-wire segment and a third connecting section electrically connected to the first connecting segment and the second connecting segment respectively.