An antenna

Abstract

The present invention discloses an antenna, comprising a first radiating portion, a second radiating portion and a coaxial line, wherein the coaxial line comprises an inner conductor and an outer conductor insulated and isolated from the inner conductor; the first radiating portion comprises a feeding arm and a first radiating arm connected to the feeding arm, a feeding point is arranged on the feeding arm, and the inner conductor is electrically connected to the feeding arm through the feeding point; the second radiating portion comprises a grounding arm, a second radiating arm and a third radiating arm, the grounding arm is arranged at intervals from the feeding arm, the second radiating arm and the third radiating arm are respectively connected to the two ends of the grounding arm and both extend toward a side away from the feeding arm; a grounding point is arranged on the grounding arm, and the outer conductor is electrically connected to the grounding arm through the grounding point. The present invention makes the antenna less affected by the feeding cable, realizes the required standing wave bandwidth within the limited length of the antenna, reduces the size of the antenna, and has a simple structure.

Description

Technical Field

[0001] The present invention relates to the field of communications, and in particular to an antenna. Background Art

[0002] With the rapid development of wireless communications and the demand for various data services, antenna design is mainly developing towards miniaturization, multi-band and broadband. Miniaturization requires the antenna to reduce its own size to adapt to the development trend of increasing integration of communication equipment and smaller and smaller volume. The existing microstrip antenna is relatively long. When the antenna length is limited, the use of the antenna is affected to a certain extent. In addition, the two microstrip antennas of the antenna are fed simultaneously on the front and back sides of the substrate with two feeding coaxial lines, which makes the feeding structure of the antenna complex. In the application, the feeding network needs at least two ports to connect to the antenna. Summary of the invention

[0003] In order to overcome the problems of large size and complex structure of existing antennas, an object of the present invention is to provide an antenna.

[0004] In order to achieve the above object, the present invention provides an antenna, comprising a first radiating portion, a second radiating portion and a coaxial line, wherein the coaxial line comprises an inner conductor and an outer conductor insulated and isolated from the inner conductor;

[0005] The first radiating portion comprises a feeding arm and a first radiating arm connected to the feeding arm, a feeding point is provided on the feeding arm, and the inner conductor is electrically connected to the feeding arm through the feeding point;

[0006] The second radiating part includes a ground arm, a second radiating arm and a third radiating arm, the ground arm is spaced apart from the feeding arm, the second radiating arm and the third radiating arm are respectively connected to two ends of the ground arm and both extend toward a side away from the feeding arm; a grounding point is provided on the ground arm, and the external conductor is electrically connected to the ground arm through the grounding point.

[0007] Preferably, the first radiating arm includes a first dipole arm, a second dipole arm, an impedance transformation feeding strip arranged between the first dipole arm and the second dipole arm and connected to one end of the feeding arm away from the ground arm, a plurality of bent microstrip lines connected to the impedance transformation feeding strip, and a first connecting arm connected to the microstrip line; the first dipole arm and the second dipole arm are respectively connected to the two ends of the feeding arm and both extend toward a side away from the ground arm.

[0008] Preferably, the first dipole arm and the second dipole arm are symmetrically arranged about a central axis of the antenna, and the central axis of the antenna is a straight line where a midpoint of the feeding arm and a midpoint of the grounding arm are located.

[0009] Preferably, the first radiating arm also includes a first reverse loading line and a second reverse loading line, the first reverse loading line and the second reverse loading line are respectively connected to the two ends of the first connecting arm and both extend toward one side of the feeding arm, the end of the first reverse loading line and the end of the first dipole arm are spaced apart, and the end of the second reverse loading line and the end of the second dipole arm are spaced apart.

[0010] Preferably, the first reverse loading line and the second reverse loading line are symmetrically arranged about the central axis of the antenna, and the central axis of the antenna is a straight line where the midpoint of the feed arm and the midpoint of the ground arm are located.

[0011] Preferably, the impedance transformation feeding strip is rectangular, trapezoidal or elliptical.

[0012] Preferably, the second radiating arm includes a third dipole arm, a fourth dipole arm and a fifth dipole arm, the third dipole arm and the fourth dipole arm are spaced apart and both extend toward a side away from the feeding arm, one end of the third dipole arm and the fourth dipole arm are both connected to the ground arm, the fifth dipole arm is bent from the other end of the third dipole arm and extends toward one side of the ground arm, and one end of the fifth dipole arm and the other end of the fourth dipole arm are spaced apart.

[0013] Preferably, the third radiating arm includes a sixth dipole arm, a seventh dipole arm and an eighth dipole arm, the sixth dipole arm and the seventh dipole arm are spaced apart and both extend toward a side away from the feeding arm, one end of the sixth dipole arm and the seventh dipole arm are both connected to the ground arm, the eighth dipole arm is bent from the other end of the sixth dipole arm and extends toward one side of the ground arm, and one end of the eighth dipole arm and the other end of the seventh dipole arm are spaced apart.

[0014] Preferably, the second radiating arm and the third radiating arm are symmetrically arranged about the central axis of the antenna, and the central axis of the antenna is a straight line where the midpoint of the feeding arm and the midpoint of the grounding arm are located.

[0015] Preferably, the antenna further includes a substrate, and the first radiating portion and the second radiating portion are both arranged on the substrate.

[0016] Preferably, the first radiating portion and the second radiating portion are arranged on the same side of the substrate.

[0017] Preferably, the coaxial line is arranged between the second radiating arm and the third radiating arm.

[0018] Preferably, the substrate is a PCB board, a metal plate or an FPC board.

[0019] Preferably, the radiation frequency bands of the antenna include 900 MHz to 940 MHz and 2.35 GHz to 2.55 GHz.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: by setting a feeding point connected to the inner conductor of the coaxial line on the first radiating part, and setting a grounding point connected to the outer conductor of the coaxial line on the second radiating part, the second radiating part includes a second radiating arm and a third radiating arm which are respectively connected to the two ends of the grounding arm and extend toward a side away from the feeding arm, thereby forming an air-permeable structure between the second radiating arm and the third radiating arm, so that the antenna is less affected by the feeding cable, and the required standing wave bandwidth is achieved within the limited length of the antenna, the size of the antenna is reduced, and the structure is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of an antenna provided by an embodiment of the present invention;

[0022] Figure 2 A schematic diagram of assembling the first radiating portion and the second radiating portion of the antenna provided in the first embodiment of the present invention;

[0023] Figure 3 A schematic diagram of assembling a first radiating portion and a second radiating portion of an antenna provided in a second embodiment of the present invention;

[0024] Figure 4 A schematic diagram of assembling a first radiating portion and a second radiating portion of an antenna provided in a third embodiment of the present invention;

[0025] Figure 5 An S-parameter diagram of an antenna provided in an embodiment of the present invention;

[0026] Figure 6 The directional diagram of the antenna provided by the embodiment of the present invention at 900 MHz;

[0027] Figure 7 The directional diagram of the antenna provided by the embodiment of the present invention at 2.45 GHz;

[0028] In the figure: 10, antenna; 1, first radiating portion; 11, feeding arm; 12, first radiating arm; 121, first dipole arm; 122, second dipole arm; 123, impedance transformation feeding strip; 124, microstrip line; 1241, U-shaped bending portion; 125, first connecting arm; 126, first reverse loading line; 127, second reverse loading line; 13, feeding point; 2, second radiating portion; 21, grounding arm; 22, second radiating Arm; 221, third dipole arm; 222, fourth dipole arm; 223, fifth dipole arm; 2231, first extension arm; 2232, second extension arm; 23, third radiation arm; 231, sixth dipole arm; 232, seventh dipole arm; 233, eighth dipole arm; 2331, third extension arm; 2332, fourth extension arm; 24, grounding point; 3, coaxial line; 31, inner conductor; 32, outer conductor; 4, substrate. DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of the present invention, the present invention is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this specification are for illustrative purposes only.

[0030] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in this specification and in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0031] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0032] like Figure 1As shown, the antenna 10 provided in the embodiment of the present invention includes a first radiating portion 1, a second radiating portion 2 and a coaxial line 3, wherein the coaxial line 3 includes an inner conductor 31 and an outer conductor 32 insulated and isolated from the inner conductor 31; the first radiating portion 1 includes a feeding arm 11 and a first radiating arm 12 connected to the feeding arm 11, a feeding point 13 is provided on the feeding arm 11, and the inner conductor 31 is electrically connected to the feeding arm 11 through the feeding point 13 to feed the first radiating arm 12; the second radiating portion 2 includes a grounding arm 21, a second radiating arm 22 and a third radiating arm 23, the ground arm 21 and the feeding arm 11 are spaced apart, a grounding point 24 is provided on the ground arm 21, and the external conductor 32 is electrically connected to the ground arm 21 through the grounding point 24; the second radiating arm 22 and the third radiating arm 23 are respectively connected to the two ends of the ground arm 21 and both extend toward a side away from the feeding arm 11, thereby forming a hollow structure between the second radiating arm 22 and the third radiating arm 23, so that the antenna 10 is less affected by the feeding cable, and the required standing wave bandwidth is achieved within the limited length of the antenna 10, the antenna size is reduced, and the structure is simple.

[0033] like Figure 2 As shown, the antenna provided by the first embodiment of the present invention, the first radiating arm 12 includes a first dipole arm 121, a second dipole arm 122, an impedance conversion feeding strip 123 disposed between the first dipole arm 121 and the second dipole arm 122 and connected to the end of the feeding arm 11 away from the ground arm 21, a multi-section bent microstrip line 124 connected to the impedance conversion feeding strip 123, and a first connecting arm 125 connected to the microstrip line 124; the first dipole arm 121 and the second dipole arm 122 are respectively connected to the two ends of the feeding arm 11 and both extend toward the side away from the ground arm 21. The impedance conversion feeding strip 123 is rectangular in shape, the cross-sectional width of the impedance conversion feeding strip 123 is greater than the width of the microstrip line 124, and the microstrip line 124 includes four periodically arranged U-shaped bending portions 1241.

[0034] In one embodiment, the feeding point 13 is arranged at the midpoint of the feeding arm 11, the grounding point 24 is arranged at the midpoint of the grounding arm 21, and the first dipole arm 121 and the second dipole arm 122 are symmetrically arranged about the central axis of the antenna (not shown in the figure), and the central axis of the antenna is the straight line where the midpoint of the feeding arm 11 and the midpoint of the grounding arm 21 are located.

[0035] like Figure 3As shown, the antenna provided by the second embodiment of the present invention is different from the first embodiment in that the first radiation arm 12 further includes a first reverse loading line 126 and a second reverse loading line 127, the first reverse loading line 126 and the second reverse loading line 127 are respectively connected to the two ends of the first connecting arm 125 and both extend toward one side of the feeding arm 11, the first reverse loading line 126 and the first dipole arm 121 are on the same straight line, and the second reverse loading line 127 and the second dipole arm 122 are on the same straight line. The end of the first reverse loading line 126 and the end of the first dipole arm 121 are spaced apart, and the end of the second reverse loading line 127 and the end of the second dipole arm 122 are spaced apart.

[0036] In one embodiment, the first reverse loading line 126 and the second reverse loading line 127 are symmetrically arranged about the central axis of the antenna. The central axis of the antenna 10 is a straight line where the midpoints of the feed arm 11 and the ground arm 21 are located.

[0037] In one embodiment, the first dipole arm 121 and the second dipole arm 122 are high-frequency radiation arms, and the length of the first dipole arm 121 and the second dipole arm 122 is 1 / 8 to 3 / 4 of the high-frequency resonance wavelength. The impedance transformation feed strip 123, the microstrip line 124, the first reverse loading line 126 and the second reverse loading line 127 are low-frequency radiation arms, and the total length of the impedance transformation feed strip 123, the microstrip line 124, the first reverse loading line 126 and the second reverse loading line 127 is 1 / 8 to 3 / 4 of the low-frequency resonance wavelength. The low-frequency radiation band of the antenna 10 is 900 MHz to 940 MHz, and the high-frequency radiation band of the antenna 10 is 2.35 GHz to 2.55 GHz.

[0038] like Figure 4 As shown, the antenna provided by the third embodiment of the present invention is different from the second embodiment in that the impedance transformation feeding strip 123 is trapezoidal. It should be noted that in other embodiments, the impedance transformation feeding strip 123 may also be elliptical.

[0039] like Figure 2-4As shown, the second radiating arm 22 includes a third dipole arm 221, a fourth dipole arm 222 and a fifth dipole arm 223, the third dipole arm 221 and the fourth dipole arm 222 are arranged at intervals and both extend toward a side away from the feeding arm 11, one end of the third dipole arm 221 and the fourth dipole arm 222 are both connected to the ground arm 21, the fifth dipole arm 223 is bent from the other end of the third dipole arm 221 and extends toward one side of the ground arm 21, and one end of the fifth dipole arm 223 and the other end of the fourth dipole arm 222 are arranged at intervals. The fifth dipole arm 223 includes a first extension arm 2231 and a second extension arm 2232, the first extension arm 2231 is connected between the second extension arm 2232 and the third dipole arm 221, the second extension arm 2232 extends toward one side of the ground arm 21, and the fourth dipole arm 222 and the second extension arm 2232 are on the same straight line.

[0040] The third radiating arm 23 includes a sixth dipole arm 231, a seventh dipole arm 232 and an eighth dipole arm 233. The sixth dipole arm 231 and the seventh dipole arm 232 are arranged at intervals and both extend toward a side away from the feeding arm 11. One end of the sixth dipole arm 231 and the seventh dipole arm 232 are both connected to the ground arm 21. The eighth dipole arm 233 is bent from the other end of the sixth dipole arm 231 and extends toward one side of the ground arm 21. One end of the eighth dipole arm 233 and the other end of the seventh dipole arm 232 are arranged at intervals. The eighth dipole arm 233 includes a third extension arm 2331 and a fourth extension arm 2332. The third extension arm 2331 is connected between the fourth extension arm 2332 and the sixth dipole arm 231. The fourth extension arm 2332 extends toward one side of the ground arm 21. The seventh dipole arm 232 and the fourth extension arm 2332 are on the same straight line.

[0041] In one embodiment, the second radiation arm 22 and the third radiation arm 23 are symmetrically arranged about the central axis of the antenna 10, and the central axis of the antenna 10 is a straight line where the midpoint of the feed arm 11 and the midpoint of the ground arm 21 are located. The fourth dipole arm 222 and the seventh dipole arm 232 are high-frequency dipole arms, and the lengths of the fourth dipole arm 222 and the seventh dipole arm 232 are 1 / 8 to 3 / 4 of the high-frequency resonance wavelength. The third dipole arm 221, the second extension arm 2232, the sixth dipole arm 231 and the fourth extension arm 2332 are low-frequency radiation arms, and the total length of the third dipole arm 221 and the second extension arm 2232 is 1 / 8 to 3 / 4 of the low-frequency resonance wavelength; the total length of the sixth dipole arm 231 and the fourth extension arm 2332 is 1 / 8 to 3 / 4 of the low-frequency resonance wavelength.

[0042] like Figure 1As shown, the antenna further includes a substrate 4, on which the first radiating portion 1 and the second radiating portion 2 are both arranged, and the substrate 4 is a PCB board, a metal plate or an FPC board. Preferably, the first radiating portion 1 and the second radiating portion 2 are arranged on the same side of the substrate 4, and the coaxial line 3 is arranged between the second radiating arm 22 and the third radiating arm 23.

[0043] Figure 5 The S parameter diagram of the antenna provided in the embodiment of the present invention shows that the antenna 10 can operate at 900MHz~940MHz and 2.35GHz~2.55GHz, with bandwidths of 40MHz (4.3%) and 200MHz (8.0%) respectively, meeting the coverage of the commonly used 900MHz and 2.45GHz frequency bands.

[0044] Figure 6 The directional diagram of the antenna provided in the embodiment of the present invention at 900 MHz, Figure 7 The directional diagram of the antenna provided in the embodiment of the present invention at 2.45 GHz shows that the antenna 10 can achieve omnidirectional coverage at both 900 MHz and 2.45 GHz, and the maximum value of the antenna radiation direction is in the horizontal direction.

[0045] The antenna 10 provided by the embodiment of the present invention is provided with a feeding point 13 connected to the inner conductor 31 of the coaxial line 3 on the first radiating part 1 of the antenna 10, and a grounding point 24 connected to the outer conductor 32 of the coaxial line 3 is provided on the second radiating part 2. The second radiating part 2 includes a second radiating arm 22 and a third radiating arm 23 respectively connected to the two ends of the grounding arm 21 and extending toward a side away from the feeding arm 11, thereby forming a permeable structure between the second radiating arm 22 and the third radiating arm 23, so that the antenna is less affected by the feeding cable. Since the low-frequency part of the antenna adopts a continuously bent structure, the size of the antenna is reduced and the structure is simple. Different effective radiating parts of the antenna are used for different frequency bands so that it can work in dual frequencies, and effectively ensure the omnidirectional radiation of the directional pattern in the two frequency bands, and the maximum inclination angle is in the horizontal direction. The antenna adopts an asymmetric structure of the upper and lower arms so that the antenna has a larger standing wave bandwidth, so that the required standing wave bandwidth can be achieved within the limited length of the antenna.

[0046] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. An antenna, characterized in that: It comprises a first radiating portion, a second radiating portion and a coaxial line, wherein the coaxial line comprises an inner conductor and an outer conductor insulated and isolated from the inner conductor; The first radiating portion comprises a feeding arm and a first radiating arm connected to the feeding arm, a feeding point is provided on the feeding arm, and the inner conductor is electrically connected to the feeding arm through the feeding point; The second radiating portion includes a ground arm, a second radiating arm and a third radiating arm, the ground arm is spaced apart from the feeding arm, the second radiating arm and the third radiating arm are respectively connected to both ends of the ground arm and both extend toward a side away from the feeding arm; a grounding point is provided on the ground arm, and the external conductor is electrically connected to the ground arm through the grounding point; the first radiating arm includes a first dipole arm, a second dipole arm, an impedance transformation feeding strip provided between the first dipole arm and the second dipole arm and connected to one end of the feeding arm away from the ground arm, a multi-section bent microstrip line connected to the impedance transformation feeding strip, and a first connecting arm connected to the microstrip line; the first radiating arm also includes a first reverse loading line and a second reverse loading line, the first reverse loading line and the second reverse loading line are respectively connected to both ends of the first connecting arm and both extend toward one side of the feeding arm, an end of the first reverse loading line is spaced apart from an end of the first dipole arm, and an end of the second reverse loading line is spaced apart from an end of the second dipole arm.

2. The antenna according to claim 1, characterized in that The first dipole arm and the second dipole arm are respectively connected to two ends of the feeding arm and both extend toward a side away from the ground arm.

3. The antenna according to claim 2, characterized in that The first dipole arm and the second dipole arm are symmetrically arranged about the central axis of the antenna, and the central axis of the antenna is a straight line where the midpoint of the feeding arm and the midpoint of the grounding arm are located.

4. The antenna according to claim 1, characterized in that The first reverse loading line and the second reverse loading line are symmetrically arranged about the central axis of the antenna, and the central axis of the antenna is a straight line where the midpoint of the feeding arm and the midpoint of the grounding arm are located.

5. The antenna according to claim 1, wherein: The impedance transformation feeding strip is rectangular, trapezoidal or elliptical.

6. The antenna according to claim 1, characterized in that The second radiating arm includes a third dipole arm, a fourth dipole arm and a fifth dipole arm, the third dipole arm and the fourth dipole arm are spaced apart and both extend toward a side away from the feeding arm, one end of the third dipole arm and the fourth dipole arm are both connected to the ground arm, the fifth dipole arm is bent from the other end of the third dipole arm and extends toward one side of the ground arm, and one end of the fifth dipole arm and the other end of the fourth dipole arm are spaced apart.

7. The antenna according to claim 6, characterized in that The third radiating arm includes a sixth dipole arm, a seventh dipole arm and an eighth dipole arm, the sixth dipole arm and the seventh dipole arm are spaced apart and both extend toward a side away from the feeding arm, one end of the sixth dipole arm and the seventh dipole arm are both connected to the ground arm, the eighth dipole arm is bent from the other end of the sixth dipole arm and extends toward one side of the ground arm, and one end of the eighth dipole arm and the other end of the seventh dipole arm are spaced apart.

8. The antenna according to claim 7, characterized in that The second radiating arm and the third radiating arm are symmetrically arranged about the central axis of the antenna, and the central axis of the antenna is a straight line where the midpoint of the feeding arm and the midpoint of the grounding arm are located.

9. The antenna according to claim 1, wherein: The antenna further includes a substrate, and the first radiating portion and the second radiating portion are both disposed on the substrate.

10. The antenna according to claim 9, characterized in that The first radiating portion and the second radiating portion are disposed on the same side of the substrate.

11. The antenna according to claim 10, characterized in that The coaxial line is arranged between the second radiating arm and the third radiating arm.

12. The antenna according to claim 9, characterized in that The substrate is a PCB board, a metal board or an FPC board.

13. The antenna according to claim 1, wherein: The radiation frequency band of the antenna includes 900 MHz to 940 MHz and 2.35 GHz to 2.55 GHz.

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