A new inverted F antenna

Abstract

The present invention discloses a novel inverted F antenna, comprising a substrate, an antenna body arranged on the substrate and a reference ground arranged on the substrate, wherein the antenna body specifically comprises a first branch and a second branch, the first side of the first branch is parallel to the reference ground, and the second side and the third side are respectively in different parabolic shapes. Through this technical solution, the overall structure of the inverted F antenna can be adjusted to achieve a significant increase in bandwidth. Actual measurements show that the bandwidth of the novel inverted F antenna obtained through this technical solution can be increased by 30% compared with the traditional inverted F antenna.

Description

Technical Field

[0001] The invention relates to the field of antennas, and in particular to a novel inverted-F antenna. Background Art

[0002] The traditional inverted F antenna is similar to the mirror image F shape, including reference ground, ground branch, feed branch, short circuit branch and open circuit branch, and each component structure is a routing type. This inverted F antenna has a simple structure, is easy to process and can be directly etched on the PCB substrate, and is currently widely used.

[0003] However, the existing inverted-F antennas are all resonant antennas with a narrow bandwidth, usually only about 5%. This is a major factor limiting the application of inverted-F antennas and is also a problem that needs to be overcome and solved urgently at the application level. Summary of the invention

[0004] In view of the above problems existing in the prior art, a new inverted F antenna is now provided, and the specific technical solution is as follows:

[0005] A novel inverted F antenna comprises a substrate, an antenna body arranged on the substrate and a reference ground arranged on the substrate;

[0006] The antenna body specifically includes:

[0007] A first branch, the first branch includes an open circuit end, a short circuit end and a feeding end, and the open circuit end, the short circuit end and the feeding end are integrated;

[0008] The feeding end includes a feeding point, and the feeding point is connected to an external radio frequency module through a connecting piece;

[0009] The open end includes an open end point;

[0010] The short-circuit terminal includes a short-circuit endpoint;

[0011] The first branch includes a first side, a second side and a third side, the first side connects the open circuit endpoint and the short circuit endpoint, the second side connects the open circuit endpoint and the feed point, and the third side connects the short circuit endpoint and the feed point;

[0012] The first side is parallel to the reference ground;

[0013] The second side is in the shape of a first parabola, and the feeding point is the vertex of the first parabola;

[0014] The third side is in the shape of a second parabola, and the feeding point is the vertex of the second parabola;

[0015] The first parabola and the second parabola have opening directions opposite to each other;

[0016] The second branch has one end connected to the short-circuit end of the first branch and the other end connected to the reference ground; the second branch is perpendicular to the first side.

[0017] Preferably, in the novel inverted-F antenna, a plane rectangular coordinate system is established with the feed point as the origin, the X-axis of the plane rectangular coordinate system is perpendicular to the first side, and the Y-axis of the plane rectangular coordinate system is perpendicular to the X-axis;

[0018] Then the first parabola satisfies the following functional relationship:

[0019] Y=0.2X 2

[0020] in:

[0021] X is the distance from any point on the second side to the Y axis;

[0022] Y is the distance from any point on the second side to the X axis.

[0023] Preferably, in the novel inverted-F antenna, a plane rectangular coordinate system is established with the feed point as the origin, the X-axis of the plane rectangular coordinate system is perpendicular to the first side, and the Y-axis of the plane rectangular coordinate system is perpendicular to the X-axis;

[0024] Then the second parabola satisfies the following functional relationship:

[0025] Y=0.05X 2

[0026] in:

[0027] X is the distance from any point on the third side to the Y axis;

[0028] Y is the distance from any point on the third side to the X axis.

[0029] Preferably, in the novel inverted-F antenna, the feed point is connected to an external radio frequency module via a copper column wire;

[0030] The copper column line includes an outer layer and an inner core, the outer layer is connected to the reference ground, one end of the inner core is connected to the first branch, and the other end of the inner core is connected to the radio frequency module.

[0031] Preferably, in the novel inverted-F antenna, the length of the first side is 60 mm.

[0032] Preferably, the impedance value of the novel inverted-F antenna is 50 ohm.

[0033] Preferably, the center frequency of the new inverted-F antenna is 490Mhz.

[0034] Preferably, the theoretical bandwidth of the new inverted-F antenna is 32Mhz.

[0035] This technical solution has the following advantages and beneficial effects:

[0036] Through this technical solution, the overall structure of the inverted F antenna can be adjusted to achieve a significant increase in bandwidth. Actual measurements have shown that the bandwidth of the new inverted F antenna obtained through this technical solution can be increased by 30% compared to the traditional inverted F antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a structural schematic diagram of a novel inverted F antenna of the present invention;

[0038] Figure 2 A schematic diagram of the functional relationship of the second side in a novel inverted-F antenna of the present invention;

[0039] Figure 3 A schematic diagram of the functional relationship of the third side in a novel inverted-F antenna of the present invention;

[0040] Figure 4 It is a structural schematic diagram of a traditional inverted F antenna in a specific embodiment of a novel inverted F antenna of the present invention;

[0041] Figure 5 A schematic diagram of simulation data of a traditional inverted-F antenna in a specific embodiment of a novel inverted-F antenna of the present invention;

[0042] Figure 6 It is a schematic diagram of simulation data of a novel inverted-F antenna in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0045] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0046] In view of the above problems existing in the prior art, a new inverted F antenna is now provided, and the specific technical solution is as follows:

[0047] A new type of inverted F antenna, such as Figure 1 As shown, it includes a substrate 1, an antenna body 2 arranged on the substrate 1 and a reference ground 3 arranged on the substrate 1;

[0048] The antenna body 2 specifically includes:

[0049] The first branch 21 includes an open circuit end 211, a short circuit end 212 and a feeding end 213, and the open circuit end 211, the short circuit end 212 and the feeding end 213 are integrated;

[0050] The feeding end 213 includes a feeding point c, and the feeding point c is connected to an external RF module 5 through a connecting member 4;

[0051] The open end 211 includes an open end point a;

[0052] The short-circuit end 212 includes a short-circuit end point b;

[0053] The first branch 21 includes a first side 2101, a second side 2102 and a third side 2103, the first side 2101 connects the open-circuit endpoint a and the short-circuit endpoint b, the second side 2102 connects the open-circuit endpoint a and the feed point c, and the third side 2103 connects the short-circuit endpoint b and the feed point c;

[0054] The first side 2101 is parallel to the reference ground;

[0055] The second side 2102 is in the shape of a first parabola, and the feeding point c is the vertex of the first parabola;

[0056] The third side 2103 is in the shape of a second parabola, and the feeding point c is the vertex of the second parabola;

[0057] The first parabola and the second parabola have opening directions opposite to each other;

[0058] The second branch 22 has one end connected to the short-circuit end 212 of the first branch 21 , and the other end connected to the reference ground 3 ; the second branch 22 is perpendicular to the first edge 2101 .

[0059] In a preferred embodiment of the present invention, the novel inverted-F antenna is arranged on a PCB substrate by etching, wherein the antenna body includes an open end 211, a short end 212 and a feeding end 213, and the open end 211, the short end 212 and the feeding end 213 are integrated into a whole, and the second branch 22 is a grounding branch of the antenna body, one end of which is connected to the short end 212, and the other end is connected to the reference ground 3.

[0060] In the above preferred embodiment, the novel inverted-F antenna modifies the vertical routing design of the traditional inverted-F antenna into a tapered transmission line: According to the principle of scaling, if all dimensions of the antenna are changed in proportion to the wavelength, the working characteristics of the antenna will remain unchanged. The principle of scaling can be used to produce a non-frequency-variant antenna whose radiation pattern and impedance characteristics do not change with frequency. The non-frequency-variant antenna is usually infinite in size, but truncating the non-frequency-variant antenna can expand the antenna bandwidth. Based on the above principle, a tapered transmission line that can effectively expand the frequency response of the impedance is applied to the inverted-F antenna, and the feed point branch and the open branch in the traditional inverted-F antenna are gradually modified into a parabolic style, which can effectively increase the bandwidth of the antenna.

[0061] As a preferred embodiment, the novel inverted F antenna, such as Figure 2 As shown, a plane rectangular coordinate system is established with the feed point c as the origin, the X axis of the plane rectangular coordinate system is perpendicular to the first side 2101, and the Y axis of the plane rectangular coordinate system is perpendicular to the X axis;

[0062] Then the first parabola satisfies the following functional relationship:

[0063] Y=0.2X 2

[0064] in:

[0065] X is the distance from any point on the second side 2102 to the Y axis;

[0066] Y is the distance from any point on the second side 2102 to the X axis.

[0067] In another preferred embodiment of the present invention, Figure 2 A plane rectangular coordinate system is established as shown, and the first parabola corresponding to the second side 2102 satisfies the following functional relationship:

[0068] Y=0.2X 2

[0069] The second side 2102 corresponds to the open end 211 of the antenna body 2. After many tests, it is believed that setting the coefficient of the first parabola corresponding to the open end 211 to 0.2 is an optimal solution.

[0070] As a preferred embodiment, the novel inverted F antenna, wherein a plane rectangular coordinate system is established with the feed point c as the origin, the X-axis of the plane rectangular coordinate system is perpendicular to the first side 2101, and the Y-axis of the plane rectangular coordinate system is perpendicular to the X-axis;

[0071] Then the second parabola satisfies the following functional relationship:

[0072] Y=0.05X 2

[0073] in:

[0074] X is the distance from any point on the third side 2103 to the Y axis;

[0075] Y is the distance from any point on the third side 2103 to the X-axis.

[0076] In another preferred embodiment of the present invention, Figure 3 A plane rectangular coordinate system is established as shown, and the first parabola corresponding to the third side 2103 satisfies the following functional relationship:

[0077] Y=0.05X 2

[0078] The second side 2103 corresponds to the short-circuit end 213 of the antenna body 2. After many tests, it is believed that setting the coefficient of the second parabola corresponding to the short-circuit end 213 to 0.05 is an optimal solution.

[0079] As a preferred embodiment, the novel inverted F antenna, such as Figure 1 As shown, the feed point c is connected to an external RF module 40 via a copper column line 4;

[0080] The copper column line 4 includes an outer layer 41 and an inner core 42 . The outer layer 41 is connected to the reference ground 3 , one end of the inner core 42 is connected to the first branch 21 , and the other end of the inner core 42 is connected to the RF module 40 .

[0081] In another preferred embodiment of the present invention, the connector 4 of the novel inverted-F antenna is a copper column wire, the outer layer 41 of the copper column wire is connected to and passes through the reference ground 3, isolating the inner core 42 from the reference ground 3, one end of the inner core 42 of the copper column wire is connected to the first branch 21 and guides the RF signal to the open end 211 of the antenna body 2 through the feeding end 213 to realize the basic function of the antenna, and the other end of the inner core 42 is connected to an external RF module 40 for transmitting related RF signals.

[0082] As a preferred implementation, in the novel inverted-F antenna, the length of the first side 2101 is 60 mm.

[0083] In another preferred embodiment of the present invention, the length of the first side 2101 is the total length of the short-circuited end 213 and the open-circuited end 211 in the new inverted-F antenna, which needs to be approximately one-fourth of the corresponding wavelength of the antenna. The user can adjust the precise length of the first side according to actual needs and the usage effect, and is not limited here.

[0084] As a preferred implementation, the impedance value of the novel inverted-F antenna is 50 ohm.

[0085] In another preferred embodiment of the present invention, the impedance value of the new inverted-F antenna can be adjusted by adjusting the setting position of the second branch 22 to adjust the distance from the feed point c to the second branch 22. The standard impedance value required for the new inverted-F antenna is 50 ohm.

[0086] As a preferred implementation, the center frequency of the new inverted-F antenna is 490Mhz.

[0087] As a preferred implementation, the theoretical bandwidth of the novel inverted-F antenna is 32 MHz.

[0088] A specific embodiment is now provided to further illustrate and describe the beneficial effects of this technical solution:

[0089] In a specific embodiment of the present invention, a comparative test is conducted by comparing with the existing traditional inverted F antenna: Figure 2 The figure shows a traditional special-shaped inverted F antenna, in which the reference ground is set to an L shape according to the application scenario. The antenna body includes an open branch, a feed point branch and a ground branch. The feed point branch passes through the reference ground through a connector and is connected to an external RF unit. The traditional inverted F antenna is simulated and tested. Figure 5 As shown, when its center frequency is 490Mhz, its bandwidth is 24Mhz; and the same simulation test is performed on the new inverted F antenna in the technical solution, such as Figure 6 As shown, when its center frequency is 490Mhz, its bandwidth is 32Mhz, which is 33% higher than the bandwidth of the prior art. In the actual measurement process, the bandwidth of this new inverted F antenna can reach 30Mhz, which is consistent with the simulation test results, and has the beneficial effect of greatly improving the antenna bandwidth.

[0090] In summary, through this technical solution, the overall structure of the inverted F antenna can be adjusted to achieve a significant increase in bandwidth. Actual measurements have shown that the bandwidth of the new inverted F antenna obtained through this technical solution can be increased by 30% compared with the traditional inverted F antenna.

[0091] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A novel inverted F antenna, comprising a substrate, an antenna body arranged on the substrate, and a reference ground arranged on the substrate; It is characterized in that The novel inverted-F antenna is disposed on the substrate by etching; The antenna body specifically includes: A first branch, wherein the first branch comprises an open circuit end, a short circuit end and a feeding end, wherein the open circuit end, the short circuit end and the feeding end are integrated into one; The feeding end includes a feeding point, and the feeding point is connected to an external radio frequency module through a connecting piece; The open end includes an open end point; The short-circuit end includes a short-circuit endpoint; The first branch includes a first side, a second side and a third side, the first side connects the open circuit endpoint and the short circuit endpoint, the second side connects the open circuit endpoint and the feed point, and the third side connects the short circuit endpoint and the feed point; The first side is parallel to the reference ground; The second side is in the shape of a first parabola, and the feeding point is the vertex of the first parabola; The third side is in the shape of a second parabola, and the feeding point is the vertex of the second parabola; The first parabola and the second parabola have opening directions opposite to each other; A second branch, one end of the second branch is connected to the short-circuit end of the first branch, and the other end of the second branch is connected to the reference ground; the second branch is perpendicular to the first side.

2. The novel inverted-F antenna as claimed in claim 1, characterized in that: Establishing a plane rectangular coordinate system with the feed point as the origin, wherein the X-axis of the plane rectangular coordinate system is perpendicular to the first side, and the Y-axis of the plane rectangular coordinate system is perpendicular to the X-axis; Then the first parabola satisfies the following functional relationship: Y=0.2X 2 in: X is the distance from any point on the second side to the Y axis; Y is the distance from any point on the second side to the X axis.

3. The novel inverted-F antenna as claimed in claim 1, characterized in that: Establishing a plane rectangular coordinate system with the feed point as the origin, wherein the X-axis of the plane rectangular coordinate system is perpendicular to the first side, and the Y-axis of the plane rectangular coordinate system is perpendicular to the X-axis; Then the second parabola satisfies the following functional relationship: Y=0.05X 2 in: X is the distance from any point on the third side to the Y axis; Y is the distance from any point on the third side to the X axis.

4. The novel inverted-F antenna as claimed in claim 1, characterized in that: The feed point is connected to an external radio frequency module via a copper column wire; The copper column line includes an outer layer and an inner core, the outer layer is connected to the reference ground, one end of the inner core is connected to the first branch, and the other end of the inner core is connected to the radio frequency module.

5. The novel inverted-F antenna as claimed in claim 1, characterized in that: The length of the first side is 60 mm.

6. The novel inverted-F antenna as claimed in claim 1, characterized in that: The impedance value of the novel inverted-F antenna is 50 ohm.

7. The novel inverted-F antenna as claimed in claim 1, characterized in that: The central frequency of the novel inverted-F antenna is 490Mhz.

8. The novel inverted-F antenna as claimed in claim 1, characterized in that: The theoretical bandwidth of the novel inverted-F antenna is 32Mhz.

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