CN106785463A - A kind of single trap ultra-wideband monopole antenna - Google Patents

Abstract

The invention discloses a single-notch ultra-broadband monopole antenna, which comprises a dielectric substrate, a ground plate is arranged on the lower surface of the dielectric substrate, a radiation patch is arranged on the upper surface of the dielectric substrate and a microstrip feeder connected to the radiation patch , a bandstop resonant unit is etched on the microstrip feeder; a through hole penetrating the radiation patch is opened at the lower part of the radiation patch. The single-notch ultra-wideband monopole antenna of the present invention etches a bandstop resonant unit on the microstrip feeder, has good notch characteristics, can effectively suppress the mutual interference between the ultra-wideband system and the WLAN system, and avoids using The deterioration of antenna radiation characteristics caused by etching grooves on the chip. The structure of the band-stop resonant unit is simple, compact, and easy to integrate without additionally increasing the size of the entire antenna, so that the antenna can be miniaturized. The antenna has the advantages of wide frequency band, small size, low cost and easy processing, and has a good pattern in the whole frequency band.

Description

A single-notch ultra-wideband monopole antenna

technical field

The invention belongs to the technical field of antennas, and in particular relates to a single-notch ultra-wideband monopole antenna.

Background technique

Ultra-Wide Band (UWB, Ultra-Wide Band) technology is a new type of wireless communication technology. According to regulations of the US Federal Communications Commission (FCC, Federal Communications Commission), the frequency band of UWB communication is 3.1 GHz to 10.6 GHz. However, this frequency range with a bandwidth of 7.5 GHz includes the operating frequencies of 5.2 GHz (5.15 GHz-5.35 GHz) and 5.8 GHz (5.725 GHz-5.825 GHz) of the current wireless local area network (WLAN). In order to avoid the interference of signals in these frequency bands, the ultra-wideband antenna is required to generate blocking in the frequency band in the range of 5 GHz to 6 GHz, that is, it has a notch (band rejection) characteristic. In addition, the current communication system tends to be more and more miniaturized and highly integrated, which also puts forward higher requirements for the miniaturized design of the antenna.

As an important type of ultra-wideband antenna, planar monopole antenna has been widely used in short-distance wireless communication systems due to its simple structure, low profile, low cost, broadband, and omnidirectional radiation.

At present, there are two main methods for planar monopole ultra-wideband antennas to realize the notch function: (1) slotting the antenna or loading parasitic elements to form a resonant structure, such as the Chinese patent application No. 201510218287. An ultra-wideband monopole antenna with trapping characteristics. The antenna etches H-shaped grooves and cross-shaped grooves on the radiation patch, thereby generating trapping characteristics in the two frequency bands of 3.3GHz to 3.7GHz and 3.7GHz to 4.2GHz. The method is to etch slots of different shapes on the antenna radiation patch, and then adjust the size of the slot to make it equal to a quarter or half of the corresponding wavelength of the center frequency to be suppressed, and then introduce Band-stop characteristics. The disadvantage of this design is that slotting in the radiation part of the antenna will cause the generation of high-order modes, so that the antenna pattern (the graphical representation of the antenna direction function is the pattern of the antenna) is distorted in the high frequency band; at the same time, the surface current is changed The flow path of the antenna also increases the cross-polarization of the antenna, which deteriorates the pattern; (2) carry out band-stop filter design on the feeder, such as the Chinese patent application No. The notch antenna implements the band-stop characteristic by using a broken-line electromagnetic band-gap (EBG, Electromagnetic Band-gap) structure symmetrically distributed on both sides of the impedance matching input microstrip line. The advantage of this method is that the designed band stop structure can be directly embedded into the microstrip line (feeder line), and better band trap performance can be achieved without optimizing other structures; the disadvantage is that the EBG structure additionally adds The size of the antenna is reduced, which is not conducive to miniaturization, and the complex structure puts forward higher requirements for processing.

Therefore, it is necessary to provide a single-notch ultra-wideband monopole antenna with good notch characteristics and a simple structure that is conducive to miniaturized design.

Contents of the invention

The purpose of the present invention is to provide a single-notch ultra-wideband monopole antenna, which can meet the requirements of good notch characteristics, simple structure and miniaturization design.

In order to solve the above-mentioned technical problems, a technical solution adopted by the present invention is: a single-notch ultra-wideband monopole antenna, comprising a dielectric substrate, the lower surface of the dielectric substrate is provided with a grounding plate, and the upper surface of the dielectric substrate is provided with A radiation patch and a microstrip feeder connected to the radiation patch, the dielectric substrate is a rectangular dielectric substrate, the radiation patch covers the upper part of the dielectric substrate, and the microstrip feeder is connected to the center of the lower edge of the radiation patch And extending downward along the long side of the rectangular dielectric substrate, a band-stop resonant unit is etched in the middle of the microstrip feeder.

In another embodiment of the single-notch ultra-broadband monopole antenna of the present invention, the lower part of the radiation patch is provided with a through hole penetrating the radiation patch.

In another embodiment of the single-notch ultra-broadband monopole antenna of the present invention, the radiation patch and the through hole are respectively an elliptical radiation patch and an elliptical through hole whose long axis extends along the broadside direction of the rectangular dielectric substrate , and the center of the elliptical radiation patch does not coincide with the center of the elliptical through hole, the minor axis of the elliptical radiation patch is collinear with the minor axis of the elliptical through hole and the long side of the rectangular dielectric substrate parallel; the ratio of the major axis to the minor axis of the elliptical radiation patch is the same as the ratio of the major axis to the minor axis of the elliptical through hole.

In another embodiment of the single-notch ultra-wideband monopole antenna of the present invention, the band stop resonant unit includes a slot that is etched through the microstrip feeder and extends along the length direction of the microstrip feeder, and in the slot along The length direction of the microstrip feeder line is extended with a first coupling line and a second coupling line parallel to each other with a coupling interval. end, the lower end of the second coupling line is integrally connected to the lower side of the slit, and the upper end of the second coupling line is an open free end.

In another embodiment of the single-notch ultra-broadband monopole antenna of the present invention, the ground plate covers the lower part of the lower surface of the dielectric substrate, and the ground plate includes a semi-ellipse whose long axis extends along the width direction of the rectangular dielectric substrate. A grounding plate and a rectangular grounding plate integrally connected with the semi-elliptical grounding plate, the semi-elliptical grounding plate is equal to the long axis and the short axis of the elliptical radiation patch; the short axis apex of the semi-elliptical grounding plate The tangent of is coincident with the projection of the tangent of the vertex of the short axis of the lower part of the elliptical radiation patch on the plane of the medium substrate.

In another embodiment of the single-notch ultra-broadband monopole antenna of the present invention, a groove is formed at the apex of the minor axis of the semi-elliptical ground plate to the center of the semi-elliptical ground plate.

In another embodiment of the single-notch ultra-broadband monopole antenna of the present invention, the long side of the dielectric substrate is 30mm, the wide side is 20mm, and the thickness is 1mm; The upper wide side of the dielectric substrate is tangent, and the two vertices of the long axis of the elliptical radiation patch are respectively tangent to the long sides of the two sides of the dielectric substrate; the long axis of the elliptical radiation patch is 20mm, and the short axis is 16mm; the major axis of the elliptical through hole is 10mm, the minor axis is 8mm, the distance between the center of the elliptical radiation patch and the center of the elliptical through hole is 3.5mm; the length of the microstrip feeder is 14mm , the width is 2mm; the etched slit on the bandstop resonant unit is a rectangular slit, the length of the rectangular slit is 5mm, the width is 1.6mm, the distance between the upper edge of the rectangular slit and the upper edge of the microstrip feeder line and The distance between the lower edge of the rectangular slot and the lower edge of the microstrip feeder is 4.5mm; the length of the first coupled line and the second coupled line are both 4.8mm and 0.2mm in width, and the first coupled line and the second coupled line The coupling interval between the coupling lines is 0.1mm; the distance between the right side of the first coupling line and the right side of the rectangular slit and the distance between the left side of the second coupling line and the left side of the rectangular slit The distance is 0.55mm.

In another embodiment of the single-notch ultra-broadband monopole antenna of the present invention, the groove is a rectangular groove with a width of 4mm and a depth of 2mm.

In another embodiment of the single-notch ultra-wideband monopole antenna of the present invention, the operating frequency range of the single-notch ultra-wideband monopole antenna is 3.1 GHz-10.6 GHz, and the notch range is 5 GHz-6 GHz.

In another embodiment of the single-notch ultra-broadband monopole antenna of the present invention, the material of the dielectric substrate is an epoxy resin material, and its relative permittivity is 4.1, and the dielectric loss tangent value is 0.02; the microstrip feeder The characteristic impedance is 50 ohms.

The beneficial effects of the present invention are: the single-notch ultra-wideband monopole antenna of the present invention etches the band-stop resonant unit on the microstrip feeder, has band-stop and slow-wave characteristics, and has good notch wave characteristics, and can effectively suppress super Interference between the broadband system and the WLAN system is avoided, and the deterioration of the antenna radiation characteristics caused by etching slots on the radiation patch is avoided. The structure of the band-stop resonant unit is simple, compact, and easy to integrate without additionally increasing the size of the entire antenna, so that the antenna can be miniaturized. The antenna has the advantages of wide frequency band, small size, low cost, and easy processing, and has a good pattern in the entire frequency band, and can also select the required notch frequency band by adjusting the length of the band-stop resonant unit. It has high application value in the application of communication system.

Description of drawings

Fig. 1 is the structural representation of the single-notch ultra-wideband monopole antenna embodiment of the present invention;

Fig. 2 a is the right view of the embodiment of the single-notch ultra-wideband monopole antenna of the present invention shown in Fig. 1;

Fig. 2b is a left view of the embodiment of the single-notch ultra-wideband monopole antenna of the present invention shown in Fig. 1;

Fig. 3 is a combined schematic diagram of the embodiment of the single-notch ultra-wideband monopole antenna shown in Fig. 2a and Fig. 2b;

Fig. 4 is a schematic structural view of the band-stop resonant unit in the embodiment of the single-notch ultra-wideband monopole antenna of the present invention shown in Fig. 3;

Fig. 5 is a comparison graph of the measured standing wave between the embodiment of the single-notch ultra-wideband monopole antenna of the present invention and the ultra-wideband monopole antenna without a resonant unit;

Fig. 6 is the xz plane radiation pattern actually measured by the embodiment of the single-notch ultra-broadband monopole antenna of the present invention;

Fig. 7 is a yz-plane radiation pattern actually measured in the embodiment of the single-notch ultra-wideband monopole antenna of the present invention.

detailed description

In order to facilitate the understanding of the present invention, the present invention will be described in more detail below in conjunction with the accompanying drawings and specific embodiments. Preferred embodiments of the invention are shown in the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

It should be noted that, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the technical field of the present invention. Terms used in the description of the present invention are only for the purpose of describing specific embodiments, and are not used to limit the present invention. The term "and/or" used in this specification includes any and all combinations of one or more of the associated listed items.

In describing specific embodiments of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", " The orientation or positional relationship indicated by "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is for convenience only The present invention is described and simplified descriptions do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and thus should not be construed as limiting the present invention. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, a feature defined as "first", "second", etc. may expressly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, the meaning of "plurality" refers to two or more than two. The term "and/or" used in this specification includes any and all combinations of one or more of the associated listed items.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be interpreted in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary; connected. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention based on specific situations.

The present invention at first explains related nouns:

Antenna pattern: the graphical representation of the antenna direction function is the antenna pattern;

Voltage standing wave ratio VSWR (Voltage Standing Wave Ratio): VSWR refers to the ratio of the voltage peak value to the voltage valley value of the standing wave (the wave formed by the superposition of two columns of traveling waves with the same frequency and amplitude, the same vibration direction, and opposite propagation direction) , when the standing wave ratio is equal to 1, it means that the impedance of the feeder and the antenna are completely matched. At this time, all the high-frequency energy is radiated by the antenna, and there is no energy reflection loss; when the standing wave ratio is infinite, it means total reflection, and the energy is not radiated at all. . In other words, the larger the standing wave ratio, the higher the reflected power, that is, the impedance mismatch;

Passband: refers to the frequency range of signals that can pass through the filter without attenuation;

Stopband: The frequency range in which the attenuation in a certain frequency range is greater than a specified value; the difference between the upper limit frequency and the lower limit frequency of the stopband is called the stopband bandwidth, which is the frequency range that prevents the signal from passing through in a certain frequency range; stopband characteristics That is, the out-of-band suppression characteristic indicates the ability of the filter to filter out clutter and is one of the most important indicators for evaluating the filter.

Center frequency: It is the frequency in the middle of the passband or stopband of the filter. It is generally used as a parameter equalization standard to calculate some parameters; the wavelength corresponding to the center frequency is the center wavelength.

As shown in Figures 1 to 4, it is a structural diagram of an embodiment of a single-notch ultra-broadband monopole antenna of the present invention. The antenna includes a dielectric substrate 6, which is a rectangular dielectric substrate. Floor 2, the grounding plate 2 is a structure equal to the width of the dielectric substrate 6; the upper surface of the dielectric substrate 6 is provided with a radiation patch 1 and a microstrip feeder 4 connected to the radiation patch 1, and the radiation patch 4 covers the dielectric substrate The upper part of the microstrip feeder 4 is connected to the center of the lower edge of the radiating patch 1 and extends downward along the long side of the rectangular dielectric substrate, and the band stop resonant unit 5 is etched on the microstrip feeder 4 .

The single-notch ultra-broadband monopole antenna of the present invention is produced on the dielectric substrate 6 by an etching method, the ground plate 2 is printed on the lower surface of the dielectric substrate 6, and the radiation patch 1 and the microstrip feeder 4 are printed on the upper surface. , and then etch the band-stop resonant unit 5 for trapping on the microstrip feeder 4 . The band-stop resonant unit 5 has band-stop and slow-wave characteristics, and good notch wave characteristics, which can effectively suppress the mutual interference between the ultra-wideband system and the WLAN system, and avoid the problem caused by etching and slotting on the radiation patch 1. The deterioration of the radiation characteristics of the antenna caused by it. The band-stop resonant unit 5 has a simple structure, and its length can be less than a quarter of the center wavelength of the stop band. It is compact and easy to integrate, so it does not increase the size of the entire antenna, so that the antenna can be miniaturized. The antenna has the advantages of wide frequency band, small size, low cost, and easy processing, and has a good pattern in the entire frequency band, and can also select the required notch frequency band by adjusting the length of the band-stop resonant unit 5 .

In order to improve the pass-band characteristics of the antenna, the microstrip feeder 4 in this embodiment is preferably a feeder with a characteristic impedance of 50 ohms; the dielectric substrate 6 is made of epoxy resin material with a relative permittivity of 4.1 and a dielectric loss tangent of 0.02. The dielectric substrate 6 has a long side of 30 mm, a wide side of 20 mm, and a thickness of 1 mm.

Further, a through hole 8 penetrating through the radiation patch 1 is opened at a position adjacent to the microstrip feeder line 4 on the radiation patch 1 , and the through hole is etched on the radiation patch 1 . In this embodiment, the radiation patch 1 and the through hole 8 are respectively an elliptical radiation patch and an elliptical through hole whose major axis extends along the width direction of the rectangular dielectric substrate. are R ₁ and R ₂ respectively, and the semi-major axis and semi-minor axis of the elliptical through hole 8 are r ₁ and r ₂ respectively. The center O a of the elliptical radiation patch 1 does not coincide with the center O _b of the elliptical through hole 8, and has _a distance L, and L is not equal to 0; The straight line where the minor axis of is located is collinear and parallel to the long side of the rectangular dielectric substrate. In addition, the vertex of the short axis on the upper part of the elliptical radiation patch 1 is tangent to the upper broadside of the dielectric substrate 6 , and the two vertices of the long axis of the elliptical radiation patch 1 are tangent to the long sides of the dielectric substrate 6 respectively. The ratio of the major axis to the minor axis of the elliptical radiation patch 1 is the same as the ratio of the major axis to the minor axis of the elliptical through hole 8 , that is, R ₂ /R ₁ =r ₂ /r ₁ . The elliptical through-hole 8 increases the effective path of the radiation current on the radiation patch 1 , which contributes to the miniaturization of the antenna.

In this embodiment, the major axis of the elliptical radiation patch 1 is preferably 20 mm, and the minor axis is preferably 16 mm; the major axis of the elliptical through hole is preferably 10 mm, and the minor axis is preferably 8 mm, and the ratio of the major axis to the minor axis of the elliptical radiation patch 1 is equal to The ratio of the major axis to the minor axis of the elliptical through hole 8 is R ₂ /R ₁ =r ₂ /r ₁ =0.8. The distance L between the center of the elliptical radiation patch 1 and the center of the elliptical through hole 8 is preferably 3.5 mm. In this embodiment, the radiation patch is designed as an ellipse whose long axis extends along the width direction of the dielectric substrate, which is conducive to reducing the size of the long side of the dielectric substrate and further contributes to the miniaturization of the antenna.

In order to improve the band-stop characteristics of the single-notch ultra-wideband monopole antenna, the structure of the band-stop resonance unit 5 of this embodiment is shown in Figure 2a, Figure 3 and Figure 4. The slot 9 on the feeder 4 and extending along the length direction of the microstrip feeder line is provided with a parallel first coupled line 71 and a second coupled line 72 extending along the lengthwise direction of the microstrip feeder line 4 in the slot 9 . The slit 9 of the present embodiment is preferably a rectangular slit, and the long side of the rectangular slit extends along the length direction of the microstrip feeder 4; the lengths of the two coupling lines are equal and less than the length of the long side of the rectangular slit, and the upper end of the first coupling line 71 is integrated Connecting the upper side of the rectangular slit, the lower end of the first coupling line 71 is an open free end, the lower end of the second coupling line 72 is integrally connected to the lower side of the rectangular slit, and the upper end of the second coupling line 72 is an open free end.

In the present embodiment, the length of the microstrip feeder 4 is 14mm, and the width is _2mm . The rectangular slit is arranged in the middle of the microstrip feeder 4. _The preferred length L2 is 5mm, and the preferred width W2 is 1.6mm. The distance between the upper side of the feeder 4 and the distance between the lower side of the rectangular slot and the lower side of the microstrip feeder ₄ are both 4.5mm; the dimensions of the two coupling lines are equal, the length L3 is 4.8mm, and the width _W3 is 0.2 mm, the coupling interval between the first coupling line 71 and the second coupling line 72 is 0.1mm, and the distance between the free ends of the two coupling lines and the corresponding upper/lower sides of the rectangular slit is 0.2mm; the first coupling line 71 and the second coupling line The two coupling lines 72 are arranged in the middle of the rectangular slit, the distance between the right side of the first coupling line 71 and the right side of the rectangular slit and the distance between the left side of the second coupling line 72 and the left side of the rectangular slit The distance between them is 0.55mm.

By adjusting the length of the rectangular slot of the band-stop resonant unit and the length of the two coupling lines, the frequency band to be suppressed can be adjusted. When the length of the rectangular slit of the band-stop resonant unit and the length of the coupling line increase, the center of the stop band of the frequency band to be suppressed will shift to the low frequency direction; conversely, when the length of the rectangular slit of the band-stop resonant unit and the length of the coupling line decrease, The center of the stop band of the frequency band to be suppressed will be shifted to the high frequency direction.

It should be noted that the shape of the slit 9 is not limited to a rectangle, but can also be any shape that has a certain extension length and can realize the above-mentioned notch function.

Further, the ground plate 2 of this embodiment covers the lower part of the lower surface of the dielectric substrate 6, and includes a semi-elliptical ground plate 21 whose long axis extends along the width direction of the dielectric substrate 6 and a semi-elliptical ground plate 21 integrally connected The rectangular ground plate 22, the long axis of the semi-elliptical ground plate 21 and the long side of the rectangular ground plate 22 are equal to the width of the dielectric substrate 6; the size of the semi-elliptical ground plate 21 is the same as that of the elliptical radiation patch 1, namely The semi-elliptical ground plate 21 is equal to the long axis and the short axis of the elliptical radiation patch. A semi-ellipse design is made on the half of the ground plate to match the shape of the radiation patch, which can increase the effective electrical length of the ground, increase the current path, and further contribute to the miniaturization of the antenna.

In addition, the tangent line of the apex of the minor axis of the semi-elliptical ground plate 21 coincides with the projection of the tangent line of the vertex of the minor axis of the lower part of the elliptical radiation patch 1 on the plane of the dielectric substrate. Further, the minor axis of the semi-elliptical ground plate in this embodiment The apex coincides with the projection of the short-axis apex of the lower part of the elliptical radiation patch on the plane of the medium substrate.

Further, in this embodiment, a groove 3 is formed at the apex of the short axis of the semi-elliptical ground plate 21, which is depressed toward the center of the semi-elliptical ground plate, and the grooves extend along the long side and the wide side of the dielectric substrate respectively. . The groove 3 in this embodiment is preferably a rectangular groove, and the rectangular groove is symmetrical about the minor axis of the semi-elliptical grounding plate. The width W ₁ of the rectangular groove extending along the wide side of the dielectric substrate is 4 mm, and the depth L ₁ of the depression extending along the long side of the dielectric substrate is 2 mm. The rectangular groove can further improve the impedance matching characteristic of the antenna, and better impedance matching can be achieved in a wide frequency range by adjusting the size of the rectangular groove.

What needs to be explained here is that the shapes of the radiation patch 1, the through hole 8 and the grounding plate 2 are not limited to ellipse, and may also be rectangular or circular, as long as the distribution characteristics of the current on the radiation patch can be changed and according to the applicable occasion Shapes that are conducive to miniaturized design are within the protection scope of the present invention.

Based on the material selection and size of the dielectric substrate 6 in this embodiment, when the notch frequency band (stop band) is 5 GHz to 6 GHz, the corresponding center frequency is 5.5 GHz, according to the relevant calculation formula: The speed of light c=3×10 ⁸ m/s, and the relative permittivity is 4.1, so the center wavelength of the stop band can be calculated as: Then a quarter of the central wavelength of the stop band is about 6.7 mm, and the preferred value of the length of the band stop resonant unit in this embodiment is 5 mm, which is less than a quarter of the central wavelength of the stop band.

The single-notch ultra-broadband monopole antenna of the present invention can increase the path of radiation current by using the through hole 8 on the radiation patch, the ground plate 2 and the groove 3, and improve the antenna impedance matching characteristics, thereby realizing the miniaturization and Broadband design; the band-stop resonant unit 5 has a simple structure, is easy to integrate, and is easy to process, and its length is less than a quarter wavelength of the center of the stop band, without additionally increasing the size of the entire antenna. The working frequency range of the antenna is 3.1GHz～10.6GHz, and the notch range is 5GHz～6GHz. The required notch frequency band can be selected by adjusting the length of the resonant unit 5. It has a high application in the application of short-distance communication systems. value.

It should be noted that in the present invention, the ground plate, the radiation patch and the microstrip feeder are all general-purpose profiles used in the industry, and their thickness complies with the industry standard, so details will not be repeated here.

Fig. 5 is the actual measurement standing wave comparison curve figure of single notch ultra-broadband monopole antenna embodiment of the present invention and no band-stop resonance unit antenna, wherein K1 is the standing wave curve figure of band-stop resonance unit antenna embodiment in the present invention , K2 is the standing wave curve of the non-bandstop resonant element antenna. It can be seen from this figure that in the 4.9GHz to 6GHz frequency band (stop band) within the frequency range of 3.0GHz to 11.3GHz, the value of the voltage standing wave ratio VSWR of the band stop resonant unit antenna in this embodiment is relatively high, and the highest value is even It reaches about 7.5, which shows that the antenna has good notch characteristics in this frequency band, avoiding mutual interference with the WLAN system, and the VSWR in other ranges is less than 2, which can meet the requirements of the FCC working frequency band. However, for an antenna without a band-stop resonant unit, the VSWR value in the entire frequency band is less than 2, which means that the antenna does not have notch characteristics in the range of 5GHz to 6GHz.

As shown in Figure 6 and Figure 7 is the radiation pattern measured by the embodiment of the notch ultra-broadband monopole antenna of the present invention, first define a three-dimensional coordinate system, take the plane where the dielectric substrate is located as the horizontal reference plane, and this embodiment stipulates that the wide side of the dielectric substrate The extending direction is the x-axis, the long-side extending direction is the y-axis, and the axis extending perpendicular to the plane where the dielectric substrate is located is the z-axis. According to the above coordinate system, Fig. 6 shows the radiation pattern of the xz plane, and Fig. 7 shows the radiation pattern of the yz plane. Taking Figure 6 as an example, the circle in Figure 6 is divided into 360 degrees, where 30, 60, etc. represent angle marks, and the radial direction represents normalized field strength values in decibels (dB). The solid line q1 in Figure 6 represents the radiation pattern when the antenna’s operating frequency is 4GHz, the dotted line q2 represents the radiation pattern when the antenna’s operating frequency is 7GHz, and the dotted line q3 represents the radiation pattern when the antenna’s operating frequency is 10GHz , it can be seen that these three frequency points all have good circumferential omnidirectional radiation characteristics. 4GHz, 7GHz and 10GHz are three frequency points selected at medium intervals in the 3.1GHz-10.6GHz frequency band, and are not within the notch range of 5GHz-6GHz. The low, medium and high frequencies of this frequency range are representative. It can be seen from Fig. 6 and Fig. 7 that the antenna has a good pattern, meets the application requirements of ultra-wideband wireless systems, and has good radiation characteristics.

The trap ultra-broadband monopole antenna of the present invention adopts the method of etching the band-stop resonant unit 5 on the microstrip feeder 4 to realize the trap. The antenna can be miniaturized; in addition, the radiation patch and the ground plate adopt a transverse elliptical structure, which is more conducive to reducing the length of the antenna, and at the same time increases the effective electrical length of the ground plate, increases the current path, and also contributes to the miniaturization of the antenna ; The rectangular groove on the ground plate can further improve the impedance matching characteristics of the antenna, and better impedance matching can be achieved in a wide frequency range by adjusting the size of the groove.

The above is only an embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural transformations made by using the description of the present invention and the accompanying drawings, or directly or indirectly used in other related technical fields, are included in the Within the scope of patent protection of the present invention.

Claims (10)

1. a kind of single trap ultra-wideband monopole antenna, including medium substrate, the lower surface of the medium substrate is provided with ground connection Plate, the upper surface of the medium substrate is provided with radiation patch and the microstrip feed line being connected with the radiation patch, its feature It is that the medium substrate is rectangle medium substrate, the radiation patch covers the top of the medium substrate, the micro-strip Feeder line be connected with the center of the lower edge of the radiation patch and along the rectangle medium substrate long side direction to downward Stretch, band resistance resonant element is etched with the middle part of the microstrip feed line.

2. single trap ultra-wideband monopole antenna according to claim 1, it is characterised in that open the radiation patch bottom It is provided with the open-work for penetrating the radiation patch.

3. single trap ultra-wideband monopole antenna according to claim 2, it is characterised in that the radiation patch and open-work Oval radiation patch and oval open-work that respectively major axis extends along the broadside of rectangle medium substrate, and it is described ellipse The center of circular radiation paster is misaligned with the center of the oval open-work, the short axle of the oval radiation patch with it is described The short axle of oval open-work is conllinear and parallel with the side long of the rectangle medium substrate；The major axis of the oval radiation patch Ratio with short axle is identical with the ratio of short axle with the major axis of the oval open-work.

4. single trap ultra-wideband monopole antenna according to claim 3, it is characterised in that the band resistance resonant element bag Etching is included on the microstrip feed line and along the gap of microstrip feed line length direction extension, along described micro- in the gap Ribbon feeder length direction is extended the first coupling line and the second coupling line parallel and be spaced with coupling, first coupling The top in gap described in the upper end integrally connected of zygonema, the lower end of first coupling line is the free end of open circuit, described second Gap is following described in the lower end integrally connected of coupling line, and the upper end of second coupling line is the free end of open circuit.

5. single trap ultra-wideband monopole antenna according to claim 4, it is characterised in that the earth plate covering is described The bottom of medium substrate lower surface, the earth plate includes the semiellipse that major axis extends along the broadside of rectangle medium substrate Shape earth plate and the rectangle earth plate being connected with half elliptic earth plate one, the half elliptic earth plate are ellipse with described The major axis of circular radiation paster is equal, and short axle is also equal；The tangent line of the minor axis vertex of the half elliptic earth plate is ellipse with described Projection of the tangent line of circular radiation paster bottom minor axis vertex in the medium substrate plane overlaps.

6. single trap ultra-wideband monopole antenna according to claim 5, it is characterised in that the half elliptic earth plate Minor axis vertex at open up the oriented half elliptic earth plate central concave groove.

7. single trap ultra-wideband monopole antenna according to claim 6, it is characterised in that the side long of the medium substrate For 30mm, broadside be 20mm, thickness be 1mm；

The minor axis vertex on the oval radiation patch top is tangent with the top broadside of the medium substrate, the oval spoke Two summits for penetrating the major axis of paster are tangent with the both sides of medium substrate side long respectively；The length of the oval radiation patch Axle is 20mm, short axle is 16mm；The major axis of the oval open-work is 10mm, short axle is 8mm, the oval radiation patch Spacing between the center of center and the oval open-work is 3.5mm；

The length of the microstrip feed line is 14mm, and width is 2mm；The gap with being etched on resistance resonant element is rectangular slits Gap, the length of the rectangular aperture is 5mm, width is 1.6mm, the top of the top of the rectangular aperture and the microstrip feed line The distance between and the distance between following of following and microstrip feed line of rectangular aperture be 4.5mm；First coupling The length of line and the second coupling line is 4.8mm, width and is 0.2mm, between first coupling line and the second coupling line Coupling is at intervals of 0.1mm；The distance between the right edge of first coupling line and right edge of the rectangular aperture and The distance between the left side of two coupling lines and the left side of rectangular aperture are 0.55mm.

8. single trap ultra-wideband monopole antenna according to claim 7, it is characterised in that the groove is that rectangle is recessed Groove, the width of the rectangular recess is 4mm, cup depth is 2mm.

9. single trap ultra-wideband monopole antenna according to claim 8, it is characterised in that single trap ultra wide band list The operating frequency range of pole sub-antenna is 3.1GHz~10.6GHz, and trap scope is 5GHz~6GHz.

10. the single trap ultra-wideband monopole antenna according to any one of claim 1~9, it is characterised in that the medium The material of substrate is epoxide resin material, and its relative dielectric constant is 4.1, and dielectric loss tangent value is 0.02；The micro-strip feedback The characteristic impedance of line is 50 ohm.