CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Chinese Patent Application No.CN201510084101.6 filed on February 15, 2015 in the State Intellectual Property Office of China, the whole disclosure of which is incorporated herein by reference. BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a technical field of antenna, more particularly, relates to a folding dipole antenna, a wireless communication module and a method of constructing the same.

Description of the Related Art By connecting internet home appliances to the Internet, interconnection among the home appliances, as well as among the home appliances, the Internet and users is achieved. Generally, the home appliances may be connected to the Internet in a wire or wireless connection mode. The wireless connection mode is widely used because it avoids the complicated cables.

Since signals of the antenna are to be blocked by metal, a wireless communication module cannot be installed in a chamber enclosed by a metal housing. On the other hand, it is desirable to install the wireless communication module in any position of the home appliance as required. Generally, there are three kinds of ways to install the wireless communication module as follows.

(1)· The antenna and the wireless communication module are made in the same PCB and installed in the home appliance. A portion of the housing of the home appliance near the wireless communication module is removed. Taking into account the robustness of the overall structure of the home appliance, it is impossible to remove too much metal. Thereby, the signal of antenna will become poor.

(2). The wireless communication module is installed in the home appliance, and the antenna is installed on the outer wall of the housing (or on the inner wall of the housing, in this case, it is also needed to remove a portion of the housing). The antenna is connected to the wireless communication module by a radio-frequency cable. Obviously, using radio-frequency cable will increase the cost and the wireless signal loss.

(3). The wireless communication module and the antenna are integrated into a single piece, installed on the outer wall of the housing of the home appliance, and connected to a main circuit board in the home appliance by a connector and cables.

The above way (3) has advantages of convenient installation, convenient updating, and excellent signals without being blocked. Hereafter, it will describe the antenna in the wireless communication module installed in the above way (3).

There are many kinds and brands of home appliances, and these kinds and brands of home appliances have different sizes and shapes. Thereby, these wireless communication modules may be required to be installed on different positions on these home appliances, and the design of the antenna is very challenging.

For example, in prior art, there is solution to use inverted F antenna, planar inverted F antenna, monopole antenna and dipole antenna, widely used in mobile terminal equipment, for example, mobile telephone, as the antenna used in the internet home appliance. But these antennas each is a non-balanced antenna, therefore, a current is produced in the metal near the antenna in work, and its performance is affected by the metal housing of the home appliance. Even installed in the central or the corner of the home appliance, the performance of the antenna also varies greatly. SUMMARY OF THE INVENTION

It would be advantageous to provide an antenna and a wireless communication module, wireless transmission performances of which are not or less affected by installation positions of them on a home appliance, and a method of constructing the antenna and the wireless communication module.

According to an aspect of the present invention, there is provided a folding dipole antenna, comprising: a first conductor segment; a first feed conductor with one end connected to the first conductor segment and the other end connected to a radio frequency signal receiving/transmitting terminal of a radio frequency processing circuit; a second conductor segment with a length substantially equal to that of the first conductor segment; a second feed conductor with one end connected to the second conductor segment and the other end connected to another radio frequency signal receiving/transmitting terminal or a ground terminal of the radio frequency processing circuit; a third conductor segment; a first connection segment configured to connect the first conductor segment and the third conductor segment; and a second connection segment configured to connect the second conductor segment and the third conductor segment, wherein the first connection segment is configured to have a length equal to that of the second connection segment, wherein the first conductor segment and the second conductor segment are separated by the first feed conductor and the second feed conductor, wherein the third conductor segment is connected in series between the first conductor segment and the second conductor segment and parallel to a composite structure composed of the first conductor segment and the second conductor segment.

According to another aspect of the present invention, there is provided a wireless communication module, comprising: a housing; a radio frequency processing circuit provided in the housing; and the above folding dipole antenna provided in the housing and connected to the radio frequency processing circuit.

According to another aspect of the present invention, there is provided a method of constructing a folding dipole antenna, comprising steps of: providing a first conductor segment; providing a first feed conductor, one end of which is connected to the first conductor segment, the other end of which is connected to a radio frequency signal receiving/transmitting terminal of a radio frequency processing circuit; providing a second conductor segment with a length equal to that of the first conductor segment; providing a second feed conductor, one end of which is connected to the second conductor segment, the other end of which is connected to another radio frequency signal receiving/transmitting terminal or a ground terminal of the radio frequency processing circuit; providing a third conductor segment; providing a first connection segment configured to connect the first conductor segment and the third conductor segment; and providing a second connection segment configured to connect the second conductor segment and the third conductor segment, wherein the first connection segment is configured to have a length substantially equal to that of the second connection segment, wherein the first conductor segment and the second conductor segment are separated by the first feed conductor and the second feed conductor, wherein the third conductor segment is connected in series between the first conductor segment and the second conductor segment and parallel to a composite structure composed of the first conductor segment and the second conductor segment.

According to another aspect of the present invention, there is provided a method of constructing a wireless communication module, comprising steps of: providing a housing; providing a radio frequency processing circuit in the housing; and providing the above constructed folding dipole antenna in the housing, wherein the folding dipole antenna is connected to the radio frequency processing circuit.

In the above various exemplary embodiments of the present invention, there is provided an antenna and a wireless communication module, wireless transmission performances of which are not or less affected by installation positions of them on a home appliance.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings, in which:

Fig.1 is an illustrative view of installing a wireless communication module with a built-in IFA antenna on a metal housing of a home appliance;

Fig. 2 shows return losses of the IFA antenna when it is placed on the centers of metal plates with different sizes;

Fig.3 is an illustrative view of placing the IFA antenna on the top corner of the metal housing with sizes of 300mmx300mmx300mm;

Fig. 4 shows return losses of the IFA antenna when it is placed on different positions of the metal housing with sizes of 300mmx300mmx300mm;

Fig.5 is a diagram of showing a radiation direction of the IFA antennas placed on the top center of the metal housing with sizes of 300mmx300mmx300mm;

Fig.6 is a diagram of showing a radiation direction of the IFA antennas placed on the top corner of the metal housing with sizes of 300mm x 300mm x 300mm;

Fig.7 is an illustrative view of a wireless communication module, in which an arc shaped folding dipole antenna is disposed, installed on the metal housing of the home appliance;

Fig.8 shows an illustrative structure of the arc shaped folding dipole antenna of Fig.7;

Fig.9 shows return losses of the arc shaped folding dipole antenna of Fig.8 when it is placed on the centers of the metal plates with different sizes;

Fig.10 shows return losses of the arc shaped folding dipole antenna of Fig.8 when it is placed on different positions of the top of the metal housing with sizes of 300mmx300mmx300mm;

Fig.11 is a diagram of showing a radiation direction of the arc shaped folding dipole antenna of Fig.8 placed on the top center of the metal housing with sizes of 300mmx300mmx300mm;

Fig.12 is a diagram of showing a radiation direction of the arc shaped folding dipole antenna of Fig.8 placed on the top corner of the metal housing with sizes of 300mmx300mmx300mm;

Fig.13 is another illustrative structure view of an arc shaped folding dipole antenna; Fig.14 is an illustrative structure view of a half I-shaped folding dipole antenna;

Fig.15 is another illustrative structure view of a half I-shaped folding dipole antenna;

Fig.16 is a flow chart showing a method of constructing a folding dipole antenna; and

Fig.17 is a flow chart showing a method of constructing a wireless communication module.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE

IVENTION

Exemplary embodiments of the present disclosure will be described hereinafter with reference to the attached drawings, wherein the like reference numerals refer to the like elements. The present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein; rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the concept of the disclosure to those skilled in the art.

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed

embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.

In prior art, the performance of a built-in IFA antenna (and a wireless communication module) used in this art is greatly affected by installation position of the antenna on the home appliance and the size of a metal plate on which the antenna is installed. As for this, it is shown in detail in Figs.1-6. In order to facilitate the description, herein, it will describe the antenna and the wireless communication module with a work frequency of 2.45GHz. But the present invention is not limited to the antenna and the wireless communication module with the work frequency of 2.45GHz, the present invention may be applied to the antenna and the wireless communication module with any work frequency.

Fig.1 is an illustrative view of installing a wireless communication module with a built-in IFA antenna on a metal housing of a home appliance (for example, a refrigerator). As shown in Fig. l, in order to clearly show the inside structure of the wireless communication module, a case of the wireless communication module is removed. In the following description of the present invention, a spherical coordinate system is used to describe the spatial characteristics of the antenna signal. As shown in Fig. l, the symbol 'phi' represents a horizontal plane angle in the spherical coordinate system; the symbol 'theta' represents an elevation angle in the spherical coordinate system, and a positive direction of Y-axis in Fig. l represents an angle equal to zero degree.

Fig. 2 shows return losses of the IFA antenna (and the wireless communication module thereof) when it is placed on the centers of metal plates with different sizes. Fig.3 is an illustrative view of placing the IFA antenna 210 on the top corner of the metal housing 10 with sizes of 300mmx300mmx300mm. Fig. 4 shows return losses of the IFA antenna when it is placed on different positions of the metal housing with sizes of 300mmx300mm><300mm. Fig.5 is a diagram of showing a radiation direction of the IFA antennas placed on the top center of the metal housing with sizes of 300mm x 300mm x 300mm, in which the frequency point is equal to 2.45GHz, the gain is equal to 3.98dBi, and the 3dB beam width is equal to 117.1 degrees. Fig.6 is a diagram of showing a radiation direction of the IFA antennas placed on the top corner of the metal housing with sizes of 300mm x 300mm x 300mm, in which the frequency point is equal to 2.45GHz.

It shows that the antenna gain in the upper half space is reduced to 0.82dB, the 3dB beam width is 158.5 degrees, and the antenna gain in the lower half space is increased to 0.49dB. When the antenna (wireless communication module) is placed on the corner of the metal housing, it shows that the antenna gain is decreased by -3.2dB in the upper half space that is required to be covered by signal, and a strong radiation is appeared in the lower half space that is not required to be covered by signal. In actual use, it will interference indoor electrical appliances or other home appliances.

Concerning the above, according to a general concept of the present invention, there is provided a folding dipole antenna, a wireless communication moudle and a method of constructing the same.

In an embodiment, the folding dipole antenna, at least comprises: a first conductor segment; a first feed conductor with one end connected to the first conductor segment and the other end connected to a radio frequency signal receiving/transmitting terminal of a radio frequency processing circuit; a second conductor segment with a length equal to that of the first conductor segment; a second feed conductor with one end connected to the second conductor segment and the other end connected to another radio frequency signal receiving/transmitting terminal or a ground terminal of the radio frequency processing circuit; a third conductor segment; a first connection segment configured to connect the first conductor segment and the third conductor segment; and a second connection segment configured to connect the second conductor segment and the third conductor segment. The first connection segment is configured to have a length substantially equal to that of the second connection segment. The first conductor segment and the second conductor segment are separated by the first feed conductor and the second feed conductor. The third conductor segment is connected in series between the first conductor segment and the second conductor segment and parallel to a composite structure composed of the first conductor segment and the second conductor segment.

In an embodiment, the wireless communication module at least comprises: a housing; a radio frequency processing circuit provided in the housing; and the above folding dipole antenna provided in the housing and connected to the radio frequency processing circuit.

Fig.7 is an illustrative view of a wireless communication module 20, in which an arc shaped folding dipole antenna 220 is disposed, installed on the metal housing 10 of the home appliance according to an embodiment of the present invention. As shown in Fig.7, in order to clearly show the inside structure of the wireless communication module, the housing of the wireless communication module is removed. But it is well known for those skilled in this art that the wireless communication module of Fig.7 should have a housing for protecting the inside circuit and the antenna.

Fig.8 shows an illustrative structure of the arc shaped folding dipole antenna 220 of Fig.7.

As shown in Figs. 7 and 8, a composite structure (an inner arc shown in Fig.8) composed of a first conductor segment 221 and a second conductor segment 222 exhibits an arc shape. A third conductor segment 223 (an outer arc shown in Fig.8) is configured as an outer arc that is concentric to the composite structure and has an arc sector angle equal to that of the composite structure.

As shown in Fig.8, if the work frequency of the antenna is equal to 2.4GHz, a total length of the inner and outer arcs and the connection segments between them is equal to about 1/2 wavelength of electromagnetic wave of 2.4GHz, that is, about 62.5mm. The antenna input impedance is varied with the changing of a width of the outer arc and the inner arc, a distance between them (or a length of the connection conductor segment), and a height of the arc surface relative to a ground surface thereof (for example, PCB below the arc surface in Fig.8).

Generally, the input impedance decreases with the increase of the width of the outer arc and the inner arc, and the input impedance bandwidth decreases with the decrease of the antenna height. Those skilled in this art may design parameters according to specific requirements, so as to produce the antenna input impedance matched with an output impedance of a radio frequency processing circuit (for example, a wireless RF chip used in the wireless communication module). In this way, it does not need to adopt passive components, for example, capacitance and inductance, to achieve the impedance matching. As shown in Fig.8, two metal pins (feed points or the above first and second feed conductors 224, 225) perpendicular to the arc surface are provided to connect the first conductor segment 221 and the second conductor segment 222 to two radio frequency signal receiving/transmitting terminals of the radio frequency processing circuit (in a case where the radio frequency processing circuit uses the differential form of input/output), respectively, or connected to a radio frequency signal receiving/transmitting terminal and a ground terminal of the radio frequency processing circuit (in a case where the radio frequency processing circuit uses the non-differential form of input/output), respectively.

Figs.9- 12 shows the performances of the wireless communication module of Fig.7 and the folding dipole antenna of Fig.8. Fig.9 shows return losses of the arc shaped folding dipole antenna of Fig.8 when it is placed on the centers of the metal plates with different sizes; Fig.10 shows return losses of the arc shaped folding dipole antenna of Fig.8 when it is placed on different positions of the top of the metal housing with sizes of 300mmx300mmx300mm;

Fig- 11 is a diagram of showing a radiation direction of the arc shaped folding dipole antenna of Fig.8 placed on the top center of the metal housing with sizes of 300mm x 300mm x 300mm, in which, the frequency point is 2.45GHz, the gain is equal to 7.58dB, and the 3dB beam width is equal to 100.1 degrees. Fig.12 is a diagram of showing a radiation direction of the arc shaped folding dipole antenna of Fig.8 placed on the top corner of the metal housing with sizes of 300mm x 300mm x 300mm, in which, the frequency point is 2.45GHz, the gain is equal to 6.28dB, and the 3dB beam width is equal to 102.1 degrees. Compared with the IFA antenna shown in Figs.2 and 4, the matching characteristics of the antenna according to the embodiments of the present invention is less affected by the installation position of the antenna, as shown in Figs.9-10. Compared with the IFA antenna shown in Figs.5 and 6, the antenna according to the embodiments of the present invention may achieve excellent radiation performance, that is, a higher gain and a higher lobe ratio, as shown in Figs.1 1 and 12, when it installed on different positions of the metal housing.

The shape shown in Figure 8 is only an example of a folding dipole antenna of the present invention, and the present invention is not limited to this. For example, the folding dipole antenna 320 may have the shape shown in Fig.13. As shown in Fig.13, the composite structure (the lower arc) composed of the first conductor segment 321 and the second conductor segment 322 also exhibits an arc shape, the third conductor segment 323 (the upper arc) is located above the composite structure and overlapped with the composite structure in a direction perpendicular to a surface where the composite structure is located. In the embodiment shown in Fig.8, the third conductor segment 223 is overlapped with (coplanar with) the composite structure in a direction perpendicular to the surface where the composite structure is located. Two metal pins (feed points or the above first and second feed conductors 324, 325) are provided to connect the first conductor segment 321 and the second conductor segment 322 to two radio frequency signal receiving/transmitting terminals of the radio frequency processing circuit, respectively.

However, in other embodiments, the third conductor segment 323 may be not coplanar with the composite structure, but parallel to each other. Similarly, the antenna input impedance may be varied with the changing of a width of the outer arc and the inner arc, a distance between them (or a length of the connection conductor segment), and a height of the arc surface relative to a ground surface thereof (for example, PCB below the arc surface in Fig.9). Generally, those skilled in this art may design parameters according to specific requirements, so as to produce the antenna input impedance matched with an output impedance of a radio frequency processing circuit.

The arc shaped folding dipole antenna in the above embodiments has characteristics of good conformal on other components of the wireless communication module or modules, or less affects the spatial layout of the other components of the wireless communication module or modules, it makes the design of the wireless communication module and the integrated circuit becomes more simple and convenient.

Also, the shape shown in Figs. 8 and 13 is also an example of the folding dipole antenna of the present invention. According to the shape of the wireless communication module, the folding dipole antenna of the embodiments of the present invention may be flexibly designed into different shapes. For example, the folding dipole antenna 420, 520 of the embodiments of the present invention may be designed to have the shape shown in Figs.14 and 15.

As shown in Fig.14, in the folding dipole antenna 420, the composite structure composed of the first conductor segment 421 and the second conductor segment 422 exhibits a half I-shape (an outer half I-shaped segment), the third conductor segment 423 (an inner half I-shaped segment) is located in a recess defined by the composite structure and forms a hollow half I-shape together with the composite structure. Two metal pins (feed points or the above first and second feed conductors 424, 425) are provided to connect the first conductor segment 421 and the second conductor segment 422 to two radio frequency signal receiving/transmitting terminals of the radio frequency processing circuit, respectively.

As shown in Fig.15, in the folding dipole antenna 520, the composite structure composed of the first conductor segment 521 and the second conductor segment 522 exhibits a half I-shape (a lower half I-shaped segment), the third conductor segment 523 (an upper half I-shaped segment) is located above the composite structure and overlapped with (that is, coplanar with) the composite structure in a direction perpendicular to the surface where the composite structure is located. Two metal pins (feed points or the above first and second feed conductors 524, 525) are provided to connect the first conductor segment 521 and the second conductor segment 522 to two radio frequency signal receiving/transmitting terminals of the radio frequency processing circuit, respectively.

Similar as the arc shape, the third conductor segment may also be parallel to the composite structure but not in the same plane.

In the embodiments shown in Figs.14 and 15, the width of the third conductor segment is equal to that of the composite structure. However, in other embodiments, the width of the third conductor segment may be different from that of the composite structure.

Similarly, the antenna input impedance is varied with the changing of a width of the inner/outer half I-shaped segment (or the upper/lower half I-shaped segment), a distance between them (or a length of the connection conductor segment), and a height of the half I-shaped segment relative to a ground surface thereof (for example, PCB below the half I-shaped segment). Generally, those skilled in this art may design parameters according to specific requirements, so as to produce the antenna input impedance matched with an output impedance of a radio frequency processing circuit.

Thereby, the folding dipole antenna of the present invention may be not limited to the shapes shown in Figs.8, 13-15. The folding dipole antenna of the embodiments of the present invention may have any suitable shape as long as it uses a balanced antenna structure.

Also, as shown in Fig.16, it is a flow chart showing a method of constructing a folding dipole antenna according to an embodiment of the present invention. In the embodiment shown in Fig.16, the method mainly comprising steps of:

providing a first conductor segment (S 1610);

providing a first feed conductor, one end of which is connected to the first conductor segment (S 1620), the other end of which is connected to a radio frequency signal receiving/transmitting terminal of a radio frequency processing circuit;

providing a second conductor segment with a length substantially equal to that of the first conductor segment (S I 630);

providing a second feed conductor (S I 640), one end of which is connected to the second conductor segment, the other end of which is connected to another radio frequency signal receiving/transmitting terminal or a ground terminal of the radio frequency processing circuit;

providing a third conductor segment (S I 650);

providing a first connection segment configured to connect the first conductor segment and the third conductor segment (S I 660); and

providing a second connection segment configured to connect the second conductor segment and the third conductor segment (S I 670),

wherein the first connection segment is configured to have a length substantially equal to that of the second connection segment, the first conductor segment and the second conductor segment are separated by the first feed conductor and the second feed conductor, and the third conductor segment is connected in series between the first conductor segment and the second conductor segment and parallel to a composite structure composed of the first conductor segment and the second conductor segment.

In some embodiments, as shown in Fig. 8, the composite structure may exhibit an arc shape, the third conductor segment 223 may be configured to be an outer arc that is concentric to the composite structure and has an arc sector angle substantially equal to that of the composite structure.

In some embodiments, as shown in Fig. 13, the composite structure exhibits an arc shape, the third conductor segment 323 is located above the composite structure and overlapped with or not overlapped with the composite structure in a direction perpendicular to the surface where the composite structure is located.

In some embodiments, as shown in Fig. 14, the composite structure may exhibit a half I-shape, the third conductor segment 423 is located in a recess defined by the composite structure and forms a hollow half I-shape together with the composite structure.

In some embodiments, as shown in Fig. 15, the composite structure may exhibit a half

I-shape, the third conductor segment 523 is located above the composite structure and overlapped with or not overlapped with the composite structure in a direction perpendicular to the surface where the composite structure is located. In the above embodiments of the antenna, a width of the composite structure, a width of the third conductor segment, a distance between the composite structure and the third conductor segment, a distance between the composite structure and a ground plane, and a distance between the third conductor segment and the ground plane are selected as required, so as to produce an antenna input impedance matched with an output impedance of the radio frequency processing circuit, so as to achieve the impedance matching.

Please be noted that the step number is only for ease of description of the embodiment of the invention, and does not represent the actual implementation order. For example, firstly providing a first feed conductor (S I 620); then providing the first conductor segment (S 1610); providing the first connection segment (1660); providing the third conductor segment (S I 650); providing the second connection segment(S 1670); providing the second conductor segment (S I 630); and finally providing the second feed conductor (S I 640). In addition, those skilled in this art may implement the method in any other order. In some cases where the antenna is formed in a single processing, the above steps may be carried out simultaneously. Thereby, the present invention is not limited to the order shown in Fig.16.

Also, as shown in Fig.17, in an embodiment of the present invention, there is provided a method of constructing a wireless communication module. The method mainly comprises steps of:

providing a housing (S 1710);

providing a radio frequency processing circuit in the housing (S I 720); and

providing the folding dipole antenna, constructed according to the solution shown in Fig.16, in the housing (S I 730),

wherein the folding dipole antenna is connected to the radio frequency processing circuit.

Similarly, as described above, the present invention is not limited to the step order shown in Fig.17.

The wireless communication module provided in the present invention has a balanced folding dipole antenna, therefore, an induction current produced in adjacent metal in use is far less than the non-balanced antenna. As a result, its performance is less affected by the metal housing of the home appliance and has very high stability.

The wireless communication module with such antenna has good universality, and may be installed on different positions of different outer surfaces of different home appliances while maintaining excellent performance, such as, low antenna return loss, high antenna efficiency and excellent radiation pattern. Also, it can meet the requirements of the home appliance of Internet of things, for example, small size and low profile of the wireless module.

It should be appreciated for those skilled in this art that the above embodiments are intended to be illustrated, and not restrictive. For example, many modifications may be made to the above embodiments by those skilled in this art, and various features described in different embodiments may be freely combined with each other without conflicting in configuration or principle.

Although several exemplary embodiments have been shown and described, it would be appreciated by those skilled in the art that various changes or modifications may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.

As used herein, an element recited in the singular and proceeded with the word "a" or "an" should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to "one embodiment" of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments "comprising" or "having" an element or a plurality of elements having a particular property may include additional such elements not having that property.