CN104051853A - communication device - Google Patents

Abstract

A communication device includes a grounding element and an antenna element. The antenna element is adjacent to the ground element and does not overlap with the ground element. The antenna element includes a first portion and a second portion. The first portion has a first end and a second end, wherein the first end is a first feeding point of the antenna element. The second portion has a third end and a fourth end, wherein the third end is a second feeding point of the antenna element, and the fourth end is an open end. A first switch is coupled between the second end of the first portion and the third end of the second portion. The first switch is also coupled to a communication module via the first portion and a first reactive circuit. A second switch is coupled to the third terminal of the second portion. The second switch is also coupled to the communication module via a second reactance circuit. The total length of the antenna element of the present invention will be much less than 0.25 wavelength of the lowest operating frequency required for a typical antenna element, and thus has the advantage of small size.

Description

communication device

technical field

The present invention relates to a communication device, in particular to a communication device including a reconfigurable dual-feed Ground Plane Antenna Element (Reconfigurable Dual-feed Ground Plane Antenna Element).

Background technique

In recent years, with the vigorous development of the wireless communication industry, the functions of mobile communication devices are also improving day by day in order to meet the diversified needs of users. Generally speaking, the mobile communication device must be in line with the trend of thinning and add related components at the same time. Therefore, how to design an antenna element with more functions in the limited space of the mobile communication device, and how to make the antenna element achieve the practical performance is an important challenge for antenna designers.

In view of this, it is necessary to design a mobile communication device including a small-sized antenna to solve the problem that the design space of the antenna element is shrinking day by day.

Contents of the invention

The object of the present invention is to provide a communication device and its reconfigurable dual-feed ground plane antenna element (Reconfigurable Dual-feed Ground Plane Antenna Element). The ground plane antenna element mainly includes an antenna element and a ground element in the communication device. The antenna element includes a first part and a second part. A switching switch is provided between the first part and the second part, so that the antenna element can obtain a combination of different current resonance paths. The switch can also be used to control the excitation of multiple different resonant modes of the antenna element, thereby achieving multi-frequency operation of the antenna element. The total length of the first portion and the second portion may be less than 0.15 wavelengths of the lowest operating frequency of the antenna element. In other words, the total length of the antenna element of the present invention is much smaller than 0.25 times the wavelength of the minimum operating frequency required by general antenna elements, thus having the advantage of small size.

In a preferred embodiment, the present invention provides a communication device, comprising: a ground element; and an antenna element, adjacent to the ground element, and not overlapping with the ground element, wherein the antenna element includes: a first part , having a first end and a second end, wherein the first end is a first feeding point of the antenna element; and a second part, having a third end and a fourth end, wherein the third end is a second feeding point of the antenna element, and the fourth end is an open end; wherein, a first switch is coupled to the second end of the first part and the third end of the second part Between terminals, the first switch is also coupled to a communication module via the first part and a first reactance circuit (reactive circuit), a second switch is coupled to the third terminal of the second part, and The second switch is also coupled to the communication module via a second reactance circuit.

In some embodiments, the antenna element generally extends along a first edge of the ground element, or extends approximately along two adjacent edges of the ground element. In some embodiments, the antenna element is adjacent to a corner of the ground element. The second portion extends approximately along a first edge of the ground element, the first portion approximately extends along a second edge of the ground element, and the first edge is adjacent to and perpendicular to the second edge.

In some embodiments, when the first switch is closed (closed, conduction) and the second switch is open (open, non-conduction), the antenna element receives feed energy via the first feed point , and operate in a first frequency band. In some embodiments, when the second switch is closed and the first switch is open, the antenna element receives feed energy through the second feed point and operates in a second frequency band. In some embodiments, the first frequency band is approximately between 704 MHz and 960 MHz, and the second frequency band is approximately between 1710 MHz and 2690 MHz.

In some embodiments, the first portion of the antenna element is roughly L-shaped or straight. In some embodiments, the second portion of the antenna element is roughly L-shaped or straight.

In the present invention, the antenna element and the ground element form an asymmetric dipole antenna (Dipole Antenna) structure, and by controlling these switches, different feeding points of the antenna element can be selectively coupled to a signal source. The antenna element can use a combination of the first part and the second part, or only the second part, to obtain different current resonance paths. The antenna element can also control the excitation of its multiple different resonant modes. In more detail, the antenna element can operate in multiple frequency bands in the following manner. When the first switch is closed and the second switch is open, the antenna element uses the combination of the first portion plus the second portion to generate resonance. In addition, with the first impedance provided by the first reactance circuit, the antenna element can resonate in the first frequency band. The total length of the first portion and the second portion is less than 0.15 times the wavelength of the lowest frequency of the first frequency band. At this time, the antenna element can generate a resonant mode to cover the low frequency operation of the antenna element. When the second switch is closed and the first switch is open, the antenna element only uses the second part to generate resonance. In addition, with the second impedance provided by the second reactance circuit, the antenna element can resonate in the second frequency band. The length of the second portion is less than 0.15 wavelengths of the lowest frequency of the second frequency band. At this point, the antenna element can generate another resonant mode to operate at the high frequency of the encompassing antenna element.

In some embodiments, the antenna element is substantially a planar structure with a total area of only about 10×30 mm ² . In some embodiments, the antenna element is switchable to operate in a low frequency band of LTE700/GSM850/900 and a high frequency band of GSM1800/1900/UMTS/LTE2300/2500. In other words, the antenna element may cover the first frequency band approximately between 704 MHz to 960 MHz, and cover the second frequency band approximately between 1710 MHz to 2690 MHz to achieve LTE/WWAN multi-band operation.

Description of drawings

FIG. 1 is a schematic diagram showing a communication device according to a first embodiment of the present invention;

Fig. 2 is a diagram showing the return loss of the antenna element according to the first embodiment of the present invention when energy is fed from the first feeding point;

Fig. 3 is a diagram showing the return loss of the antenna element according to the first embodiment of the present invention when energy is fed from a second feeding point;

Fig. 4 is a graph showing the antenna efficiency when the antenna element according to the first embodiment of the present invention is fed with energy from the first feeding point;

Fig. 5 is a graph showing the antenna efficiency when the antenna element is fed with energy from the second feeding point according to the first embodiment of the present invention;

FIG. 6 is a schematic diagram showing a communication device according to a second embodiment of the present invention;

FIG. 7 is a schematic diagram showing a communication device according to a third embodiment of the present invention.

[Description of reference signs of main components]

100, 600, 700～communication device;

10 ~ grounding element;

101～the first edge of the grounding element;

102～the second edge of the grounding element;

11, 61, 71 ~ antenna elements;

12, 62, 72 ~ the first part of the antenna element;

13, 63, 73 ~ the second part of the antenna element;

121, 621, 721～the first end of the first part (the first feeding point);

122, 622, 722 ~ the second end of the first part;

131, 631, 731 ~ the third end of the second part (the second feeding point);

132, 632, 732 ~ the fourth end of the second part;

14, 64, 74 ~ the first switch;

15, 65, 75 ~ the second switch;

16, 66, 76 ~ the first reactance circuit;

17, 67, 77 ~ the second reactance circuit;

18～communication module;

21 ~ the first frequency band;

31 ~ the second frequency band;

41, 51～antenna efficiency curve.

Detailed ways

In order to make the above objects, features and advantages of the present invention more comprehensible, specific embodiments of the present invention are listed below, together with the accompanying drawings, for a detailed description as follows.

FIG. 1 is a schematic diagram showing a communication device 100 according to a first embodiment of the present invention. The communication device 100 can be a smart phone (Smart phone), a tablet computer (Tablet Computer), or a notebook computer (Notebook Computer). As shown in FIG. 1 , the communication device 100 includes at least a ground element 10 and an antenna element 11 . The antenna element 11 generally extends along a first edge 101 of the ground element 10 . The ground element 10 can be a metal plane laid on a dielectric substrate (not shown), such as an FR4 substrate or a system circuit board. The antenna element 11 is adjacent to the ground element 10 and does not overlap with the ground element 10 . The antenna element 11 includes a first portion 12 and a second portion 13 . In this embodiment, the first portion 12 is roughly L-shaped, and the second portion 13 is roughly straight. The present invention is not limited thereto. In other embodiments, any one of the first part 12 and the second part 13 can be roughly straight, L-shaped, J-shaped, U-shaped, W-shaped, or An S shape and so on. The first part 12 has a first end 121 and a second end 122 , wherein the first end 121 is a first feeding point of the antenna element 11 . The second part 13 has a third end 131 and a fourth end 132 , wherein the third end 131 is a second feeding point of the antenna element 11 , and the fourth end 132 is an open end. The first switch 14 is coupled between the second end 122 of the first part 12 and the third end 131 of the second part 13 . The first switch 14 is also coupled to a communication module 18 via the first portion 12 and a first reactance circuit 16 . A second switch 15 is also coupled to the third terminal 131 of the second part 13 . The second switch 15 is also coupled to the communication module 18 via a second reactance circuit 17 . The first reactance circuit 16 provides a first impedance value, and the second reactance circuit 17 provides a second impedance value, wherein the first impedance value may be different from the second impedance value. In some embodiments, the first reactance circuit 16 and the second reactance circuit 17 each include one or more inductors and capacitors, such as chip inductors and chip capacitors. The communication module 18 can be regarded as a signal source of the antenna element 11 . By controlling the first switch 14 and the second switch 15, the antenna element 11 selectively uses the first feed point or the second feed point to receive the feed energy from the signal source to operate in different frequency band. The types of the first switch 14 and the second switch 15 are not limited in the present invention. For example: the first switch 14 and the second switch 15 can be implemented with a PIN diode (PIN diode) respectively. In some embodiments, the communication device 100 further includes a control unit (not shown), which can selectively turn on or off the first switch 14 and the first switch 14 according to a user input signal or a detection signal. Any one of the second switch 15. In some embodiments, the communication device 100 further includes a sensor (not shown), which can detect the frequency of a nearby electromagnetic signal and generate the detection signal accordingly. It should be noted that the communication device 100 may also include other components, such as a touch panel, a processor, a speaker, a battery, and a casing (not shown).

FIG. 2 is a diagram showing the return loss (Return Loss) of the antenna element 11 according to the first embodiment of the present invention when energy is fed from the first feeding point (the first end 121 of the first part 12 ). In this embodiment, the total area of the ground element 10 is about 100×150 mm ² , which is the size of the ground element of a typical tablet computer, while the total area of the antenna element 11 is only about 10×30 mm ² . When the first switch 14 is closed and the second switch 15 is open, the antenna element 11 uses the combination of the first part 12 and the second part 13 to generate resonance to form a first frequency band 21 . In a preferred embodiment, the first frequency band 21 may cover LTE700/GSM850/900 frequency bands (approximately between 704 MHz and 960 MHz). In this embodiment, the total length of the first part 12 and the second part 13 is less than 0.15 times the wavelength of the lowest frequency of the first frequency band 21 .

FIG. 3 is a diagram showing the return loss of the antenna element 11 according to the first embodiment of the present invention when energy is fed from the second feeding point (the third end 131 of the second part 13 ). When the second switch 15 is closed and the first switch 14 is open, the antenna element 11 only uses the second part 13 to generate resonance to form a second frequency band 31, wherein the second frequency band 31 can cover GSM1800/1900/UMTS/ LTE2300/2500 frequency band (approximately between 1710MHz and 2690MHz). In this embodiment, the length of the second portion 13 is less than 0.15 times the wavelength of the lowest frequency of the second frequency band 31 .

FIG. 4 is a diagram showing the antenna efficiency (Antenna Efficiency) when the antenna element 11 according to the first embodiment of the present invention is fed with energy from the first feeding point. In this embodiment, the first switch 14 is closed, and the second switch 15 is open. As shown in FIG. 4 , the antenna efficiency curve 41 represents the antenna efficiency of the antenna element 11 operating in the LTE700/GSM850/900 frequency bands. From the results, it can be seen that the antenna element 11 has good antenna efficiency (radiation efficiency taking the S parameter into consideration) when operating in each frequency band of LTE700/GSM850/900, which meets the requirements of practical applications.

FIG. 5 is a diagram showing the antenna efficiency of the antenna element 11 according to the first embodiment of the present invention when energy is fed through the second feeding point. In this embodiment, the second switch 15 is closed, and the first switch 14 is open. As shown in FIG. 5 , the antenna efficiency curve 51 represents the antenna efficiency of the antenna element 11 operating in the GSM1800/1900/UMTS/LTE2300/2500 frequency bands. From the results, it can be seen that the antenna element 11 has good antenna efficiency (radiation efficiency with S parameters taken into consideration) when operating in GSM1800/1900/UMTS/LTE2300/2500 frequency bands, which meets the requirements of practical applications.

FIG. 6 is a schematic diagram showing a communication device 600 according to a second embodiment of the present invention. In the second embodiment, an antenna element 61 may be adjacent to a corner of the ground element 10 and substantially extend along two adjacent edges of the ground element 10 , so as to save the internal design space of the communication device 600 . In the second embodiment, a first portion 62 of the antenna element 61 is roughly L-shaped, and a second portion 63 of the antenna element 61 is also roughly L-shaped. The remaining features of the second embodiment are similar to those of the first embodiment, so both embodiments can achieve similar operational effects.

FIG. 7 is a schematic diagram showing a communication device 700 according to a third embodiment of the present invention. In the third embodiment, an antenna element 71 is adjacent to a corner of the ground element 10 . A second portion 73 of the antenna element 71 extends substantially along a first edge 101 of the ground element 10, and a first portion 72 of the antenna element 71 extends approximately along a second edge 102 of the ground element 10, so as to save the communication device The interior design space of 700 , wherein the first edge 101 is adjacent to and perpendicular to the second edge 102 . In the third embodiment, the first portion 72 of the antenna element 71 is substantially straight, and the second portion 73 of the antenna element 71 is also substantially straight. The remaining features of the third embodiment are similar to those of the first embodiment, so the two embodiments can achieve similar operational effects.

It should be noted that the above-mentioned element sizes, element shapes, and frequency ranges are not limitations of the present invention. Antenna designers can adjust these settings according to different needs.

The ordinal numbers in this description and the scope of the patent application, such as "first", "second", "third" and so on, have no sequential relationship with each other, and are only used to mark and distinguish between two different elements of the name.

Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the scope of the present invention. Any skilled person familiar with the common knowledge in the art may make some changes without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims (10)

1. A communication device, comprising: a grounding element; and An antenna element is adjacent to the ground element and does not overlap with the ground element, wherein the antenna element includes: a first portion having a first end and a second end, wherein the first end is a first feed point of the antenna element; and a second portion having a third end and a fourth end, wherein the third end is a second feeding point of the antenna element, and the fourth end is an open end; Wherein, a first switching switch is coupled between the second terminal of the first part and the third terminal of the second part, and the first switching switch is also coupled to A communication module, a second switch is coupled to the third end of the second part, and the second switch is also coupled to the communication module via a second reactance circuit. 2. The communication device as claimed in claim 1, wherein the antenna element extends approximately along a first edge of the ground element, or approximately extends along two adjacent edges of the ground element. 3. The communication device according to claim 1, wherein the antenna element is adjacent to a corner of the ground element, the second portion extends substantially along a first edge of the ground element, the first portion substantially extends along the ground element A second edge of the ground element extends, and the first edge is adjacent to and perpendicular to the second edge. 4. The communication device as claimed in claim 1, wherein when the first switch is closed and the second switch is open, the antenna element receives feed energy through the first feed point, and operates at a first feed point a frequency band. 5. The communication device as claimed in claim 4, wherein when the second switching switch is closed and the first switching switch is open, the antenna element receives fed energy via the second feeding point, and operates at a first Second band. 6. The communication device as claimed in claim 5, wherein the first frequency band is approximately between 704 MHz to 960 MHz, and the second frequency band is approximately between 1710 MHz to 2690 MHz. 7. The communication device as claimed in claim 4, wherein the first reactance circuit provides a first impedance value so that the antenna element resonates in the first frequency band, and the total length of the first part and the second part is less than the 0.15 times the wavelength of the lowest frequency of the first frequency band. 8. The communication device as claimed in claim 5, wherein the second reactance circuit provides a second impedance value so that the second part resonates in the second frequency band, and the length of the second part is less than that of the second frequency band 0.15 times the wavelength of the lowest frequency. 9. The communication device as claimed in claim 1, wherein the first portion is roughly L-shaped or straight. 10. The communication device as claimed in claim 1, wherein the second portion is roughly L-shaped or straight.