Multi-frequency and broadband short-circuit inverted-F-shaped antenna

Abstract

The invention discloses a multi-frequency and broadband short-circuit inverted F-shaped antenna, which comprises a radio frequency circuit area with a function of improving the efficiency of the antenna; the feed-in point is arranged in the radio frequency circuit area and is used for welding a preset cable; the signal line is arranged in the radio frequency circuit area, two sides of the signal line are respectively spaced from the radio frequency circuit area, and one end of the signal line is electrically connected to the feed-in point; the radiation area is arranged on at least one side edge of the radio frequency circuit area, the radiation area comprises a low / intermediate frequency common path extending from the other end of the grounding wire to the first direction, an intermediate frequency radiation part extending from the tail end of the low / intermediate frequency common path to the second direction and a low frequency radiation path extending to the third direction and allowing a low frequency signal to pass through; the low-frequency path extends towards a fourth direction through a turn to form a low / high-frequency radiation part, and a short circuit area for high-frequency signals to pass through is formed on the inner side surrounded by the low / high-frequency radiation part, the low / intermediate-frequency common path and the low-frequency path.

Description

Technical Field

[0001] The present invention relates to a multi-band and broadband short-circuit inverted F-shaped antenna, and more particularly to a miniaturized multi-band and broadband antenna, which realizes an antenna with high isolation and omnidirectional radiation field in a limited space of a wireless communication electronic device and in an environment with multiple antennas. Background Art

[0002] Wireless communication technology is an indispensable part of today's convenient life. In addition to the comprehensive deployment of wired and wireless local area networks, wireless communication devices must also be equipped with wireless antennas to receive and transmit signals. Only then can mobile electronic devices use the Internet and transmit data through wireless local area networks.

[0003] The antenna of the wireless communication electronic device mentioned above is usually a single entity or integrated with other antennas with different functions. Its volume is usually relatively large, which affects the circuit layout of the wireless communication electronic device. In the past, the antenna can only have a bandwidth utilization rate of about 7%, which cannot achieve broadband and multi-band performance. The radiation field of the antenna cannot achieve a complete broadband frequency band due to the limited space of the wireless communication electronic device, and cannot have good isolation in the wireless communication electronic device with multiple antennas. According to the above, the operating bandwidth of the wireless antenna is required to be designed towards the multi-band and broadband frequency band. How to increase the frequency band and improve the bandwidth without occupying too much space inside the wireless communication electronic device has become a goal that those engaged in this industry are eager to work hard for. Summary of the invention

[0004] Therefore, in view of the above problems and deficiencies, the main object of the present invention is to provide a multi-band and broadband short-circuited inverted-F antenna.

[0005] The present invention provides a multi-band and broadband short-circuit inverted F-type antenna, comprising: a radio frequency circuit area, which has the function of improving antenna performance; a feeding point, which is arranged in the radio frequency circuit area and is provided with a preset cable for welding; a signal line, which is arranged in the radio frequency circuit area, and there is a spacing between the two sides of the signal line and the radio frequency circuit area, and one end of the signal line is electrically connected to the feeding point; a radiation area, which is arranged at least one side of the radio frequency circuit area, the radiation area includes a low / medium frequency common path extending from the other end of the ground line toward the first direction, an intermediate frequency radiation part extending toward the second direction at the end of the low / medium frequency common path and a low frequency radiation path extending toward the third direction for low frequency signals to pass through, the low frequency path extends toward the fourth direction through a turn to have a low / high frequency radiation part, and a short circuit area for high frequency signals to pass through is formed inside the low / high frequency radiation part, the low / medium frequency common path and the low frequency path. The above-mentioned antenna has a simple structure and good performance, and the antenna can be made in a planar or three-dimensional form. The antenna also has a single feed structure of a coplanar waveguide (CPW). The signal line of the short-circuited inverted F-type antenna is electrically connected to the ground area through a ground wire, so that broadband and multi-band performance from MHz to mmWave (millimeter wave) can be achieved; at the same time, it is easy to make multiple antennas with high isolation in the multi-sided RF circuit area.

[0006] The shortest path from the low / medium frequency common path to the low / high frequency radiation part in the short-circuit area forms a high frequency short-circuit area, and the length of the high frequency short-circuit area is one wavelength divided by one quarter of the high frequency center frequency.

[0007] The preferred implementation shape of the short-circuit area is a triangle, and the high-frequency short-circuit area is formed on the hypotenuse of the triangle.

[0008] The intermediate frequency radiation portion is provided with a top loading portion protruding toward at least one side for impedance matching of the resonance frequency band, and the top loading portion is in a rectangular shape.

[0009] The low / medium frequency common path is provided with a first open-circuit stub and a second open-circuit stub at the other side of the short-circuit region, and the first open-circuit stub is in a rectangular shape and the second open-circuit stub is in a straight line shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a structural diagram of the short-circuited inverted-F antenna of the present invention from a first perspective.

[0011] Figure 2 This is a structural diagram of the short-circuited inverted-F antenna of the present invention from a second viewing angle.

[0012] Figure 3 It is a schematic diagram of the conduction and radiation paths of the low-frequency, medium-frequency and high-frequency paths of the short-circuited inverted-F antenna of the present invention.

[0013] Figure 4 FIG. 4 is another structural diagram of the short-circuit region of the short-circuit inverted-F antenna of the present invention.

[0014] Figure 5 This is another structural diagram of a shortcut area of ​​a short-circuited inverted-F antenna according to the present invention.

[0015] Figure 6 The present invention is a structural diagram of an implementation of arranging a plurality of short-circuited inverted-F antennas in a radio frequency circuit area.

[0016] Figure 7 Another embodiment of the present invention is to set a plurality of short-circuited inverted-F antennas in the radio frequency circuit area.

[0017] Figure 8 The figure is a table showing the 3D radiation efficiency of the short-circuited inverted-F antenna of the present invention at each frequency band.

[0018] Explanation of the reference numerals: 1-short-circuited inverted-F antenna; 11-RF circuit area; 110-spacing; 12-coupling surface; 13-feeding point; 14-signal line; 15-radiation area; 151-low / medium frequency common path; 152-medium frequency radiation part; 153-low frequency path; 154-low / high frequency radiation part; 155, 155a, 155b-short-circuit area; 1551-high frequency short circuit; 156-top loading part; 157-first open-circuit section; 158-second open-circuit section. DETAILED DESCRIPTION

[0019] In order to achieve the above-mentioned purpose and effect, the technical means and structures adopted by the present invention are illustrated in detail with reference to the preferred embodiments of the present invention, and their features and functions are described as follows for a complete understanding.

[0020] See also Figure 1-2 As shown in the figure, the first perspective structure diagram and the second perspective structure diagram of the short-circuited inverted F-type antenna of the present invention are respectively shown. It can be clearly seen from the figure that the main components and features of the multi-band and broadband short-circuited inverted F-type antenna of the present invention are described in detail as follows, which include:

[0021] A radio frequency circuit area 11 has the function of improving the antenna performance.

[0022] A feeding point 13 is disposed in the RF circuit area 11 and is provided for welding a preset cable (not shown).

[0023] A signal line 14 is disposed in the RF circuit area 11 . A gap 110 exists between two sides of the signal line 14 and the RF circuit area 11 . One end of the signal line 14 is electrically connected to the feeding point 13 .

[0024] A radiation area 15 is provided at at least one side of the RF circuit area 11, the radiation area 15 includes a low / medium frequency common path 151 extending from the other end of the signal line 14 toward the first direction, an intermediate frequency radiation portion 152 extending toward the second direction at the end of the low / medium frequency common path 151 and a low frequency path 153 extending toward the third direction for a low frequency resonant signal to pass through, the low frequency path 153 extends toward the fourth direction through a turn to have a low / high frequency radiation portion 154, and a short circuit area 155 for a high frequency signal to pass through is formed inside the low / high frequency radiation portion 154, the low / medium frequency common path 151 and the low frequency path 153; the first direction differs from the fourth direction by 180 degrees; and the second direction differs from the third direction by 180 degrees.

[0025] The short-circuited inverted F-type antenna 1 is a planar antenna printed on a printed circuit board (PCB). The RF circuit area 11 and the radiation area 15 are arranged on the first surface of the printed circuit board, and the second surface of the printed circuit board is also provided with a coupling surface 12 (such as Figure 2 As shown), the coupling surface 12 corresponds to the RF circuit area 11, and the RF circuit area 11 covers the signal line 14, which can increase the high-frequency bandwidth of the antenna; alternatively, the short-circuited inverted-F antenna 1 is composed of a three-dimensional metal antenna, but the three-dimensional metal antenna does not include the coupling surface 12 like a planar antenna, and a general technician familiar with this technology can use the circuit board grounding area or the metal shell of the wireless communication electronic device (not shown) as the coupling surface 12 to achieve the matching coupling or frequency band adjustment of the three-dimensional metal antenna.

[0026] The RF circuit area 11 and the coupling surface 12 are rectangular with similar or same areas.

[0027] The shortest path from the low / medium frequency common path 151 to the low / high frequency radiation portion 154 in the short-circuit area 155 forms a high frequency short circuit 1551 , and the length of the high frequency short circuit 1551 is one quarter wavelength (1 / 4λ) of the high frequency center frequency.

[0028] The preferred embodiment of the short-circuit region 155 is a triangle, and the high-frequency short circuit 1551 is formed on the hypotenuse of the triangle; however, the present invention does not limit the shape of the short-circuit region. Figure 4 The shortcut area 155a provided is in a stepped shape; or Figure 5The shortcut areas 155b provided in the shape of multiple arc edges are all feasible structures. As long as the high-frequency short circuit (the short circuit area 155a in the shape of a step or the oblique edge of the short circuit area 155b in the shape of multiple arc edges) can meet the length of one quarter wavelength (1 / 4λ) of the high-frequency center frequency, the effect of the high-frequency short circuit can be achieved. Not only the high-frequency resonance part, but also the path length of other parts such as the low-frequency resonance or the intermediate-frequency resonance must also meet the low-frequency center frequency or the intermediate-frequency center frequency One quarter wavelength (1 / 4λ) to achieve broadband and multi-frequency performance optimization.

[0029] The intermediate frequency radiation portion 152 is provided with a top-loading portion 156 protruding toward at least one side thereof for impedance matching of the frequency band, and the top-loading portion 156 is in a rectangular shape.

[0030] The low / medium frequency common path 151 has a first open-stub 157 and a second open-stub 158 protruding from the other side of the short-circuit region 155 , and the first open-stub 157 is a rectangle and the second open-stub 158 is a straight line.

[0031] The low frequency operating frequency band of the short-circuited inverted F-shaped antenna 1 is 2.4 to 2.5 GHz; the medium frequency operating frequency band is 5.15 to 5.85 GHz; and the high frequency operating frequency band is 5.925 to 7.125 GHz. Figure 3 As shown, the conduction and radiation path of the low frequency signal is from the signal line 14, the low / medium frequency common path 151, the low frequency path 153 and the low / high frequency radiation part 154; the conduction and radiation path of the medium frequency resonance signal is from the signal line 14, the low / medium frequency common path 151 and the medium frequency radiation part 152; the conduction and radiation path of the high frequency resonance signal is from the signal line 14, the high frequency short circuit 1551 of the short circuit area 155 and the low / high frequency radiation part 154. The above three different conduction and radiation paths are used to form a multi-band and wideband antenna frequency band.

[0032] See also Figure 6 , Figure 7 As shown in FIG. 1 , there are respectively an implementation structure diagram of the present invention in which a plurality of short-circuited inverted F-type antennas are arranged in the radio frequency circuit area and another implementation structure diagram, wherein Figure 6 A radiation area 15 is provided on each of the two adjacent sides of the RF circuit area 11, and the intermediate frequency radiation parts 152 of the two radiation areas 15 intersect with the forward virtual extension line (not shown in the figure); furthermore, Figure 7 Each of the four sides of the RF circuit area 11 is provided with a radiation area 15, and the forward virtual extension lines (not shown) of the intermediate frequency radiation parts 152 of the four radiation areas 15 are divided into two groups to form an intersection. Through the above, an omnidirectional antenna with high isolation is formed and can be applied to different wireless communication electronic devices.

[0033] See also Figure 8 As shown, it is a 3D radiation efficiency table of the short-circuited inverted-F antenna of the present invention in each frequency band. The peak gain range of each sampling point in the low, medium and high frequency operating bands of the short-circuited inverted-F antenna 1 of the present invention is between 1.13 and 3.34 dBi; and the efficiency range is between 49.28 and 76.07%. Both the peak gain and the efficiency are within the applicable range of each frequency band of the short-circuited inverted-F antenna 1.

[0034] The short-circuited inverted-F antenna 1 provided by the present invention has the following characteristics:

[0035] 1. The signal feeding structure of the short-circuited inverted-F antenna 1 adopts a symmetrical (or asymmetrical) coplanar waveguide (CPW) feeding method. By making the coupling surface 12 of the short-circuited inverted-F antenna 1 correspond to the RF circuit area 11, and the RF circuit area 11 covers the signal line 14, the high-frequency bandwidth of the antenna can be increased.

[0036] 2. A top-loading portion 156 is provided on the intermediate frequency radiation portion 152; a first open-stub 157 and a second open-stub 158 are provided on the other side of the short-circuit region 155 on the low / intermediate frequency common path 151. The aforementioned structures can improve the impedance matching and bandwidth of the antenna's operating frequency band.

[0037] 3. A plurality of radiation areas 15 are provided on at least two sides of the radio frequency circuit area 11 to form an omnidirectional antenna with high isolation and applicable to different wireless communication electronic devices.

[0038] 4. The short-circuited inverted-F antenna 1 can be manufactured in a planar or three-dimensional form to achieve antenna manufacturing diversity for application in various wireless communication electronic devices, and can also achieve broadband and multi-band performance from MHz to mmWave (millimeter wave).

[0039] The above are only preferred embodiments of the present invention, which do not limit the scope of the present invention. Therefore, all simple modifications and equivalent structural changes made using the contents of the present invention's specification and drawings should be included in the protection scope of the present invention and are hereby stated.

[0040] In summary, the multi-band and broadband short-circuited inverted-F antenna of the present invention can truly achieve its efficacy and purpose when used, so the present invention is truly an invention with excellent practicality.

Claims

1. A multi-band and broadband short-circuited inverted-F antenna, characterized in that: include: A radio frequency circuit area, which has the function of improving antenna performance; A feed point, which is located in the radio frequency circuit area and is used for welding a preset cable; A signal line is arranged in the radio frequency circuit area, with a distance between two sides of the signal line and the radio frequency circuit area, and one end of the signal line is electrically connected to the feeding point; as well as A radiation zone is arranged on at least one side of the radio frequency circuit zone, the radiation zone includes a low / medium frequency common path extending from the other end of the signal line toward the first direction, an intermediate frequency radiation portion extending toward the second direction at the end of the low / medium frequency common path and a low frequency path extending toward the third direction for low frequency signals to pass through, the low frequency path extends toward a fourth direction through a turn to have a low / high frequency radiation portion, and a short circuit zone for high frequency signals to pass through is formed inside the low / high frequency radiation portion, the low / medium frequency common path and the low frequency path.

2. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 1, characterized in that: The inverted F-shaped antenna is a planar antenna printed on a printed circuit board. The radio frequency circuit area and the radiation area are arranged on the first surface of the printed circuit board, and a coupling surface is also arranged on the second surface of the printed circuit board.

3. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 2, wherein: The radio frequency circuit area and the coupling surface are formed by a rectangle or a long rectangle with a similar or same area.

4. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 1, wherein: The short-circuit inverted-F antenna is composed of a three-dimensional metal antenna.

5. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 1, wherein: The shortest path from the low / medium frequency common path to the low / high frequency radiation portion in the short-circuit area forms a high-frequency short circuit, and the length of the high-frequency short circuit is one quarter of the wavelength of the high-frequency center frequency.

6. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 4, characterized in that: The preferred implementation shape of the short-circuit area is a triangle, and the high-frequency short circuit is formed on the hypotenuse of the triangle.

7. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 1, wherein: The intermediate frequency radiation part is provided with a top loading part protruding toward at least one side for impedance matching of the frequency band, and the top loading part is in a rectangular shape.

8. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 1, wherein: The low / medium frequency common path is provided with a first open circuit stub and a second open circuit stub protrudingly on the other side of the short circuit area, wherein the first open circuit stub is in a rectangular shape and the second open circuit stub is in a straight line shape.

9. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 1, wherein: The short-circuit inverted F-shaped antenna has a low-frequency operating band of 2.4 to 2.5 GHz, a medium-frequency operating band of 5.15 to 5.85 GHz, and a high-frequency operating band of 5.925 to 7.125 GHz.

10. The multi-band and broadband short-circuited inverted-F antenna as claimed in claim 1, wherein: The first direction differs from the fourth direction by 180 degrees; and the second direction differs from the third direction by 180 degrees.

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