CN106067596A - Miniaturization broadband medium resonator antenna based on coplanar wave guide feedback - Google Patents

Abstract

The invention discloses a miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding, which includes a dielectric substrate, a coplanar waveguide and a ring dielectric resonator, and the coplanar waveguide includes a ground floor, a radiation patch and a feeding part , the feeding part includes a circular patch and a central strip line, the grounding floor consists of two parts and the two parts have a symmetrical structure with respect to the central strip line, there are two symmetrical L-shaped notches and a rectangular notch on the grounding floor, and the radiation patch It consists of four pairwise symmetrical quarter-ring patches, and the ring dielectric resonator is located in the middle of the feeding part of the ring patches. The present invention excites multiple working modes of the resonator by adopting the hybrid radiation mechanism of the coplanar waveguide feeding ring printed monopole antenna and the dielectric resonator antenna, thereby expanding the bandwidth, and having good impedance matching, radiation efficiency and peak gain , to ensure that the antenna can obtain broadband working performance under the premise of small size.

Description

Miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding

technical field

The invention relates to an antenna, in particular to a miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding.

Background technique

At present, with the rapid development of microwave circuits, miniaturization, high efficiency, and broadband have become the development trend of antennas. Therefore, realizing the miniaturization and broadband of antennas has become an important content of antenna design. Many applications, such as digital broadcasting, video conferencing, satellite communications, wireless and radar, require relatively wide bandwidth. However, in previous designs, to achieve the miniaturization of the antenna, its bandwidth must be sacrificed. With the development of wireless communication technology, researchers have been trying to design antennas with small size and broadband characteristics, and the dielectric resonator antenna is undoubtedly a good choice. Compared with the traditional antenna, the dielectric resonator antenna not only has the advantages of high efficiency, convenient feeding, and simple structure, but also can control the radiation pattern of the antenna by changing the shape or selecting the appropriate mode excitation. At present, the dielectric resonator with high dielectric constant can realize the miniaturization of the antenna, but at the same time, the bandwidth of the antenna will be reduced. How to obtain the antenna with small size and broadband characteristics still needs to be further studied.

Contents of the invention

The invention aims at at least solving the technical problems existing in the prior art, and particularly innovatively proposes a miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding.

In order to achieve the above object of the present invention, the present invention provides a miniaturized wide-band dielectric resonator antenna based on coplanar waveguide feeding, including a dielectric substrate and coplanar antennas arranged on the dielectric substrate and distributed in an axisymmetric structure. A waveguide and a ring dielectric resonator, the coplanar waveguide includes a ground floor, a radiation patch and a feeder part, the feeder part includes a ring patch and a central strip line, the ground floor includes two parts and the two parts are opposite It has a symmetrical structure on the central strip line, and has two symmetrical L-shaped notches and a rectangular notch on the ground floor. The radiation patch is composed of four symmetrical quarter-ring patches. The ring patch is arranged in the upper left, lower left, upper right, and lower right directions of the annular patch of the feeding part, and the circular arc is opposite to the annular patch of the feeding part; the ring dielectric resonator is located in the ring patch of the feeding part. Right in the middle of the patch.

The present invention excites multiple working modes of the resonator by adopting the hybrid radiation mechanism of the coplanar waveguide feeding ring printed monopole antenna and the dielectric resonator antenna, thereby extending the bandwidth, and having good impedance matching, radiation efficiency and peak gain . It is guaranteed that the antenna can obtain broadband working performance under the premise of small size.

Compared with the current technical solution for extending the bandwidth of the dielectric resonator antenna, the present invention adopts the design method of the mixed structure of the circular printed monopole antenna fed by the coplanar waveguide and the dielectric resonator antenna, which not only has a significant advantage in expanding the impedance bandwidth, but also Improving other structural properties and indicators of the antenna includes: 1) reducing the section height of the antenna, which is at least 4 times lower than the method of using a stacked structure; 2) preparing the antenna by planar printing, so that The antenna has a simple form, a compact structure, and is easy to integrate without significantly reducing the radiation performance of the antenna, such as the front-to-back ratio of radiated energy and the peak gain. Moreover, by changing the thickness of the substrate and the size of the ring dielectric resonator, the working frequency band of the antenna can be adjusted arbitrarily, and can be widely used in wireless communication systems such as WLAN and WiMAX.

In a preferred embodiment of the present invention, the L-shaped notch on the ground floor is located on two edges of the ground floor that are far from the central strip line of the feeder part, and the rectangular notch on the ground floor is located On the two edges that are closer to the central strip line of the feeder part.

The L-shaped notch design can effectively adjust the matching degree of the antenna, especially in the working frequency band of 2.6GHZ-3.6GHZ, the impedance matching is significantly improved. The rectangular notch design is mainly for impedance matching of the coplanar waveguide feeder, so that the overall matching degree of the antenna is improved. Compared with the ordinary cylindrical dielectric resonator, the ring dielectric resonator increases the working bandwidth of the antenna.

Description of drawings

Fig. 1 is the overall structural diagram of the miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding of the present invention;

Fig. 2 is the top view of the coplanar waveguide part of the miniaturized broadband dielectric resonator antenna based on the coplanar waveguide feeding of the present invention;

Fig. 3 is the side view of the miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding of the present invention;

Fig. 4 is the relationship diagram between frequency and reflection coefficient |S 11| of the miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding in the present invention;

Fig. 5 is the radiation pattern on the XOZ plane and the YOZ plane obtained by the simulation of the miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding in the present invention, the dotted line represents the cross polarization pattern, and the solid line represents the coplanar polarization direction Figure; sub-figures (a), (b), (c), (d), (e), (f) respectively represent the XOZ plane at the frequency point of 4GHz, the YOZ plane at the frequency point of 4GHz, and the frequency point of 5.5GHz The XOZ plane when the frequency is 5.5GHz, the XOZ plane when the frequency is 6.3GHz, and the radiation pattern of the YOZ plane when the frequency is 6.3GHz.

Reference signs: 1 ring patch; 2 central strip line; 3 ground floor; 4 radiation patch; 5 L-shaped notch; 6 rectangular notch; 7 circular dielectric resonator; 8 dielectric substrate.

detailed description

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

In describing the present invention, it should be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", The orientation or positional relationship indicated by "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than Nothing indicating or implying that a referenced device or element must have a particular orientation, be constructed, and operate in a particular orientation should therefore not be construed as limiting the invention.

In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be mechanical connection or electrical connection, or two The internal communication of each element may be directly connected or indirectly connected through an intermediary. Those skilled in the art can understand the specific meanings of the above terms according to specific situations.

As shown in Fig. 1, Fig. 2 and Fig. 3, the present invention provides a miniaturized wide-band dielectric resonator antenna based on coplanar waveguide feeding, including a dielectric substrate and an axisymmetric structure arranged on the dielectric substrate. Coplanar waveguides and toroidal dielectric resonators. In this embodiment, both the coplanar waveguide and the annular dielectric resonator have an axisymmetric structure, and the coplanar waveguide is printed on the upper layer of the dielectric substrate 8 .

The coplanar waveguide includes a metal ground floor 3 , a radiation patch 4 and a feed part, wherein the feed part includes a ring feed patch 1 and a central strip line 2 . In this embodiment, one side of the central strip line 2 is connected to the loop feed patch 1 , and the side opposite to the loop feed patch 1 is aligned with the edge of the dielectric substrate 8 . In this embodiment, the central strip line 2 may be, but not limited to, a 50-ohm central strip line.

The grounding floor 3 includes two parts and the two parts have a symmetrical structure relative to the central strip line 2. There are two symmetrical L-shaped notches 5 and rectangular notches 6 on the grounding floor. Each part of the grounding floor 3 has an L-shaped notch 5 and a rectangular notch 6. The radiation patch 4 is composed of four symmetrical quarter-circle patches, and the four circular patches are arranged in the upper left, lower left, upper right, and lower right positions of the annular patch 1 of the feeding part. The circular arc is opposite to the annular patch 1 of the feeding part. The annular dielectric resonator 7 is located in the middle of the annular patch 1 of the feeding part. In this embodiment, the length L1 of the central strip line 2 of the feeding part is 15-17 mm, the width W1 is 2.5-3.5 mm, the inner radius R1 of the circular patch 2 of the feeding part is 6.5-7.5 mm, and the outer ring The radius R2 is 7.5 to 8.5 mm. Preferably, the length L1 is 15 mm, the width w1 is 3 mm, the inner radius R1 of the ring is 7 mm, and the outer radius R2 is 8 mm.

In this embodiment, the L-shaped notch 5 on the ground floor is located on two edges of the ground floor that are far from the central strip line 2 of the feeder part. As shown in Figure 2, the L-shaped notch is divided into two parts, which are formed by splicing two rectangles with different lengths and widths. Strip line 2), part of which is located on the vertical edge far from the center strip line 2 of the feeder part on the ground floor (parallel to the center strip line 2). Among them, the length L3 of the rectangle perpendicular to the central belt line 2 is 6.5-7.5 mm, and the width W3 is 1.2-1.7 mm; the length L of the rectangle parallel to the central belt line 2 is 35-45 mm, and the width W5 is 3-45 mm. 4mm. In a more preferred embodiment, L3 is selected as 7mm, W3 is 1.5mm; the length L of the longitudinal rectangle is 40mm, and the width W5 is 3.5mm. The L-shaped notch design and the above dimensions can effectively adjust the matching degree of the antenna, especially in the working frequency band of .6GHZ-3.6GHZ, the impedance matching is significantly improved.

The rectangular notch of the grounding floor is located on the two edges of the grounding floor that are close to the center strip line 2 of the feeder part, that is, on the corner of the grounding floor that is close to the ring patch 1 of the feeder part, and the length L4 of the rectangular notch is 1.5 ~2.5mm, the width W2 is 3~4mm, preferably the length L4 is 2mm, and the width W2 is 3.5mm. The rectangular notch design and size selection are mainly for impedance matching of the coplanar waveguide feeder, so that the overall matching degree of the antenna is improved.

For the four symmetrical quarter-ring patches in the coplanar waveguide part, the inner radius R4 of the ring is 4.5-5.5 mm, and the outer radius R5 is 5.5-6.5 mm. The preferred ring inner radius R4 is 5 mm, and outer radius R5 is 6 mm. The design of the quarter-circle patch is mainly to excite the two resonant frequency points in the high-frequency band, thereby expanding the overall bandwidth of the antenna.

The thickness of the dielectric substrate is uniform, the length L of the dielectric substrate is 36-42 mm, the width W is 30-40 mm, the thickness H1 of the dielectric substrate is 1.2-1.6 mm, and the relative dielectric constant ε ₁ of the material is between 4-5. The preferred length L of the dielectric substrate is 40 mm, the width W is 35 mm, the thickness of the dielectric substrate is 1 mm, and the relative dielectric constant of the material is 4.4.

The thickness H2 of the ring dielectric resonator is 0.5-1.5 mm, the inner radius R5 of the ring is 2.5-3.5 mm, the outer radius R6 of the ring is 5.5-6.5 mm; the relative permittivity ε ₂ is between 9 and 15. For a preferred ring dielectric resonator, the height of the resonator is 1 mm, the inner radius of the ring is 3 mm, the outer radius is 6 mm, and the relative permittivity of the material is 10.2. Compared with the ordinary cylindrical dielectric resonator, the ring dielectric resonator is chosen to increase the working bandwidth of the antenna.

Moreover, by changing the thickness of the substrate and the size of the ring dielectric resonator, the working frequency band of the antenna can be adjusted arbitrarily, and can be widely used in wireless communication systems such as WLAN and WiMAX.

After completing the above-mentioned initial design, in a preferred embodiment of the present invention, the present invention uses the high-frequency electromagnetic simulation software HFSS13.0 to carry out the simulation experiment, and the simulation research shows that the antenna can be well applied in the current wireless communication system , the optimal size of each parameter obtained through the HFSS optimization function is shown in Table 1.

Table 1. Optimum size table for each parameter

parameter mm parameter mm L 40 L1 16 W 35 L2 14 W1 3 L3 7 W2 3.5 L4 2 W3 1.5 L5 14.5 W4 4.7 L6 0.8 W5 3.5 R1 8 W6 0.5 R2 7 R3 5 R4 6 R5 3 R6 6

In this embodiment, the thickness of the metal-coated copper on the surface of the dielectric substrate is 0.017mm, the thickness of the dielectric substrate is 1mm, the material used is FR4, and the relative permittivity is 4.4.

The height of the ring dielectric resonator is 1 mm, the inner radius of the ring is 3 mm, the outer radius is 6 mm, and the relative permittivity of the material is 10.2.

According to the above parameters, the antenna of the present invention is simulated and calculated by using HFSS, and the reflection coefficient curve of the antenna and the radiation pattern of the antenna are obtained. As shown in Figure 4 and Figure 5.

Fig. 4 is a simulation curve diagram of the reflection coefficient of the present invention. It can be seen from the figure that there are three resonant frequency points, namely 4GHz, 5.5GHZ and 6.3GHz. Under the condition of |S 11|<-10dB, the impedance bandwidth frequency range of the antenna is 2.92-7.16GHz, and the relative bandwidth reaches 84.8%.

Figure 5 is the radiation pattern of the antenna on the XOZ plane and YOZ plane at 4GHz, 5.5GHZ and 6.3GHz, where (a) shows the radiation pattern of the antenna on the XOZ plane at 4GHz, and (b) shows The radiation radiation pattern of the antenna on the YOZ plane at 4GHz, (c) shows the radiation radiation pattern of the antenna on the XOZ plane at 5.5GHZ, and (d) shows the radiation radiation pattern of the antenna on the YOZ plane at 5.5GHZ , Figure (e) shows the radiation pattern of the antenna on the XOZ plane at 6.3GHz, and Figure (f) shows the radiation pattern of the antenna on the YOZ plane at 6.3GHz. Dashed lines indicate cross-polarization patterns, and solid lines indicate co-planar polarization patterns. According to Figures (a)(c) and (b)(d), it can be seen that the antenna is at 4GHz, and the radiation pattern of the antenna is similar to that of the basic dipole antenna. The radiation pattern of the XOZ plane is a typical two-way radiation, and the YOZ plane of the antenna radiates The pattern is approximately an omnidirectional radiation pattern with little cross-polarization in the direction of maximum radiation. As the frequency increases, the radiation pattern of the antenna is deformed, and the cross polarization becomes serious, which deteriorates the performance of the antenna and affects the work of the antenna. This situation is unavoidable for dielectric resonator antennas, and the main reason for this situation is the appearance of high-order modes, which destroy the antenna radiation pattern. But overall, the antenna radiation pattern is good.

In the description of this specification, descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications, substitutions and modifications can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the invention is defined by the claims and their equivalents.

Claims (8)

1. A miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding, characterized in that: it comprises a dielectric substrate and is arranged on the dielectric substrate in an axisymmetric structure distribution of coplanar waveguides and circular ring dielectric resonators device, the coplanar waveguide includes a ground floor, a radiation patch and a feeder part, the feeder part includes a ring patch and a central strip line, and the ground floor includes two parts and the two parts are symmetrical with respect to the central strip line The structure has two symmetrical L-shaped notches and a rectangular notch on the ground floor, and the radiation patch is composed of four pairwise symmetrical quarter-ring patches, and the four ring patches are arranged on the The upper left, lower left, upper right, and lower right directions of the annular patch of the feeding part, and the arc is opposite to the annular patch of the feeding part; The annular dielectric resonator is located in the middle of the annular patch of the feeding part. 2. The miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding according to claim 1, wherein the L-shaped notch on the ground floor is located at a distance from the center strip line of the feed part on the ground floor On the two farther edges, the rectangular notches of the grounding floor are located on the two edges of the grounding floor that are closer to the central strip line of the feeder part. 3. The miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding according to claim 1 or 2, characterized in that: the L-shaped notch on the ground floor consists of two rectangular shapes with different lengths and widths. It is formed by splicing, wherein the length L3 of the rectangle perpendicular to the rectangular feeder part is 6.5-7.5 mm, and the width W3 is 1.2-1.7 mm; the length L of the rectangle parallel to the rectangular feeder part is 35-45 mm, and the width W5 is 3-4 mm. 4. The miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding according to claim 1 or 2, characterized in that: the length L4 of the rectangular notch is 1.5-2.5mm, and the width W2 is 3-4mm . 5. The miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding according to claim 1, characterized in that: the length L1 of the central strip line of the feeding part is 15-17 mm, and the width W1 is 2.5-3.5 mm. mm, the inner radius R1 of the annular patch of the feeding part is 6.5-7.5 mm, and the outer ring radius R2 is 7.5-8.5 mm. 6. The miniaturized wide-band dielectric resonator antenna based on coplanar waveguide feeding according to claim 1, characterized in that: four pairwise symmetrical quarter ring patches of the coplanar waveguide part, the circle The inner radius R4 of the ring is 4.5-5.5mm, and the outer radius R5 is 5.5-6.5mm. 7. The miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding according to claim 1, characterized in that: the thickness of the dielectric substrate is uniform, the length L of the dielectric substrate is 36-42 mm, and the width W is 30 mm. ~40mm, the thickness H1 of the dielectric substrate is 1.2~1.6mm, and the relative dielectric constant ε1 ^of the material is between 4-5. 8. The miniaturized broadband dielectric resonator antenna based on coplanar waveguide feeding according to claim 1, characterized in that: the thickness H2 of the annular dielectric resonator is 0.5-1.5 mm, and the inner radius R5 of the annular ring is 2.5 ~ 3.5mm, the ring outer radius R6 is 5.5 ~ 6.5mm; its relative permittivity ε ² is between 9 and 15.