CN211530188U - Novel end-fire antenna based on split ring resonator - Google Patents

Abstract

The utility model discloses a novel end-fire antenna based on a split resonant ring, which comprises a dielectric substrate and a metal patch. The metal patch includes a feed monopole patch, a rectangular reflector, a concave reflector, multiple pairs of split resonant rings and a ground plate; the signal end of the microstrip feeder is connected to the feed monopole patch , the ground end of the microstrip feed line is connected to the ground plate; a concave reflector is placed on the left side of the feed monopole patch, and a rectangular reflector is placed on the substrate surface on the back of the concave reflector; symmetrical along the end-fire direction load multiple pairs of split resonators. The antenna of the utility model adopts a concave reflector, which improves the matching of the antenna at low frequencies; the open resonant ring is used to load the antenna in the end-fire direction, so that the electromagnetic waves are converged and the antenna gain is improved. The utility model antenna has compact structure, small overall size and high application value.

Description

A new type of end-fire antenna based on split resonator

technical field

The utility model relates to an end-fire antenna, in particular to a novel end-fire antenna based on a split resonant ring, which belongs to the technical field of antennas.

Background technique

With the gradual deepening of social informatization and intelligence, electromagnetic technology has been widely used in communication, detection, navigation and other fields. Antenna is the bridge of energy conversion in wireless communication system. Modern wireless communication system puts forward higher and higher requirements on the structure and performance of antenna. In particular, broadband, high gain and directivity have become the most important performance indicators of the antenna. With the development of wireless technology, antennas with broadband, high gain, and unidirectional radiation patterns have a wide range of application requirements in systems such as satellite communication and point-to-point communication. Microstrip line-fed end-fire antennas have attracted extensive attention due to their high gain, low power consumption, wide frequency band and simple structure.

Compared with other antennas, end-fire antennas have high gain and good directivity. In daily applications, end-fire antennas have good directivity and higher gain than dipole antennas. It is particularly effective for direction finding and long-distance communication. End-fire antennas can be used in many occasions, such as drones, missiles, satellites and other aircraft systems engineering. Conventional broadband end-fire antenna structures mainly include logarithmic periodic antennas, Yagi antennas, and gradient slot-line antennas. Take Yagi antenna as an example, this antenna is widely used in wireless network card, TV reception, and signal transmission of radio stations. In military equipment, end-fire antennas are a research hotspot in the field of antennas, but traditional Yagi antennas have a narrow operating bandwidth, a low operating frequency band, and a slightly larger volume.

SUMMARY OF THE INVENTION

Purpose of the utility model: In view of the deficiencies of the prior art, the utility model proposes a novel end-fire antenna based on a split resonant ring.

Technical solution: The new type of end-fire antenna based on split resonant ring described in the present utility model includes a dielectric substrate and a metal patch; wherein: the metal patch includes a feed monopole patch, a rectangular reflector, and a concave surface. A reflector, multiple pairs of split resonator rings and a ground plate; the signal end of the microstrip feeder is connected to the feed monopole patch, and the ground end of the microstrip feeder is connected to the ground plate; the left side of the feed monopole patch A concave reflector is placed on the side, and a rectangular reflector is placed on the substrate surface on the back of the concave reflector; multiple pairs of split resonators are loaded symmetrically along the end-fire direction. Because the feed monopole radiates an omnidirectional field, there will be electromagnetic waves radiated backwards, so a concave reflector is placed on the left side of the monopole, and a rectangular reflector is placed on the substrate surface corresponding to the concave reflector to improve radiation. , so that the energy is concentrated to the right side of the feed monopole. As a kind of artificial electromagnetic material, the split resonator has the characteristics of near zero refractive index or low refractive index, which can make electromagnetic waves converge, thereby improving the directivity of the antenna. The new end-fire antenna improves the antenna gain by symmetrically loading multiple pairs of split resonator rings along the end-fire direction, while maintaining the antenna's broadband characteristics. The back of the dielectric substrate is covered with a ground plate as a part of the feeder, so as to realize the impedance matching of the antenna in the frequency band.

Further, the dielectric substrate is an FR4 dielectric substrate, which effectively reduces the antenna cost and environmental applicability.

Preferably, the novel end-fire antenna adopts six pairs of symmetrical split resonator rings, which can effectively improve the directivity of the end-fire antenna.

Further, a rectangular slot is opened on the top of the feed monopole patch.

Further, the concave surface of the concave reflector is arc-shaped.

Beneficial effects: The utility model is based on the special resonance effect of the split resonant ring (SRR) structure, which makes the utility model antenna compact in structure, small in overall size and high in application value. The antenna of the utility model adopts a concave reflector, which improves the matching of the antenna at low frequencies, and the impedance bandwidth reaches 73.6% (2-4.21G), which fully covers the S-band. The utility model adopts the split resonant ring to be loaded in the end-fire direction of the antenna, so that electromagnetic waves are converged, and the gain of the antenna is improved while maintaining a wide frequency band.

Description of drawings

1 is a schematic diagram of the structure of an antenna split resonator ring (SRR) of the present invention;

Fig. 2 is the front structure schematic diagram of the antenna of the present invention;

3 is a schematic view of the back structure of the antenna of the present invention;

Fig. 4 is the three-dimensional structure schematic diagram of the antenna of the present invention;

Fig. 5 is the return loss diagram of the present utility model antenna;

Fig. 6 is the E-plane radiation pattern when the frequency of the antenna of the present invention is 2.4GHz, 3GHz and 3.83GHz;

7 is the radiation pattern of the H plane when the antenna frequencies of the present utility model are 2.4GHz, 3GHz and 3.83GHz;

FIG. 8 is a gain diagram of the antenna of the present invention.

Detailed ways

The technical solution of the antenna of the present invention will be further introduced below with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a schematic structural diagram of an antenna split resonator ring (SRR) of the present invention. As a kind of artificial electromagnetic material, the split resonator can focus the beam and improve the directivity of the antenna. The split resonant ring is equivalent to an equivalent circuit, and the resonant frequency is determined by the inductance and capacitance of the resonant ring. Therefore, the inductance value in the equivalent circuit can be changed by changing the dimensions of the peripheral ring and the folded portion. Change the pitch of the bent parts to change the capacitance value in the equivalent circuit. The length of a of the split resonant ring is 5.5mm, the length b is 12mm, the bending length c is 8mm, the width s is 0.7mm, and the interval d is 0.6mm. The refractive index of the dielectric plate loaded with the split resonator structure is smaller than that of the dielectric plate without the split resonator structure. When the electromagnetic wave radiated by the monopole in the end-fire direction is incident on the loaded split resonator structure, it is incident from the medium with a large refractive index to the In a medium with a small refractive index, the electromagnetic waves are converged, which enhances the radiation characteristics, thereby increasing the gain.

FIG. 2 is a schematic view of the front structure of the antenna of the present invention. Including: FR4 dielectric substrate, its volume is 108mm*50mm*1.6mm; concave reflector 1, the concave surface is arc-shaped, its length is 50mm, its long axis width is 19mm, and its short axis width is 9mm; feed monopole 2, the size is 22mm*14mm; the split resonator ring 3, the spacing between them is 8mm.

FIG. 3 is a schematic view of the back structure of the antenna of the present invention. A rectangular reflector 4 with a length of 50mm and a width of 9mm and a ground plate 5 with a length of 14mm and a width of 13mm are included to ensure impedance matching. Two cells are printed on the bottom of the media board.

FIG. 4 is a schematic diagram of the three-dimensional structure of the antenna of the present invention. The concave reflector 1 and the rectangular reflector 4, as reflectors of the utility model antenna, play the role of reflecting electromagnetic waves and improve the directivity of the antenna. By increasing the size of the concave reflector 1, the resonance length of the excitation current on the surface of the antenna is increased, so that the matching of the antenna at low frequencies is improved. Therefore, by changing the size of the long axis of the concave reflector 1, the bandwidth at the low frequency is changed, and finally a broadband effect is achieved. The ground plate 5 is used as a part of the 50 ohm microstrip line to realize the impedance matching of the antenna in the 2GHz-4.21GHz frequency band, which can meet the impedance matching requirements below -10dB, and its size has a great impact on the impedance matching. influences. When the width of the ground plate increases, the high-frequency impedance matching is improved first, and when it reaches a certain value, the coupling between the ground plate 5 and the feed monopole 2 is too large, which makes the antenna work poorly at high frequencies. The width of the ground plate 5 is 13mm and the length is 14mm. The utility model also opens a large rectangular slot on the top of the feed monopole 2, the length and width of which are 4mm and 3mm, which further reduces the return loss and improves the radiation intensity.

Fig. 5 is the return loss diagram of the antenna of the present invention. It can be seen from Figure 5 that the impedance bandwidth reaches 73.6% (2-4.21G), which fully covers the S-band, and the return loss is as low as -47dB. The distance between the concave reflector 1 and the feed monopole 2 and the distance between the split resonator 3 and the feed monopole 2 also have a great influence on the antenna performance. The end-fire antenna is coupled to the reflector 1 and the split resonator 3 through the electromagnetic wave radiated by the feed monopole 2, so that the antenna has end-fire characteristics. If the spacing is too small, the end-fire effect will not be obvious; if the spacing is too large, it will increase the difficulty of coupling electromagnetic waves, making it inconvenient to transmit energy. After repeated simulations, the distance between the reflector 1 and the feed monopole 2 is set as 6mm, and the distance between the split resonator ring 3 and the driver is set as 5mm.

Fig. 6 is the E-plane radiation pattern when the frequency of the antenna of the present invention is 2.4GHz, 3GHz and 3.83GHz. It can be seen from Figure 6 that the electromagnetic energy is mainly concentrated in a fixed direction and has good end-fire characteristics.

7 is the radiation pattern of the H-plane when the frequencies of the antenna of the present invention are 2.4GHz, 3GHz and 3.83GHz. It can be seen from the figure that the electromagnetic energy is mainly concentrated in a fixed direction and has good end-fire characteristics.

FIG. 8 is a gain diagram of the antenna of the present invention. As the frequency increases, the beams on both sides also narrow, which means that the gain reaches a maximum of 10.3dB as the frequency gradually increases.

The embodiments of the present utility model are described in detail above with reference to the accompanying drawings, but the present utility model is not limited to the above-mentioned embodiments, and various changes can be made within the knowledge scope possessed by those of ordinary skill in the art. For example, in the above embodiment, the shape of the concave reflector is appropriately changed, and the shape and area of the docking floor are changed to adapt to other operating frequencies; the shape of the split resonator itself and its layout on the substrate are changed. Changes, such as the layout to be asymmetric to meet special requirements, etc.

Claims (5)

1. The utility model provides a novel end fire antenna based on split ring resonator which characterized in that: the metal patch comprises a dielectric substrate and a metal patch; wherein: the metal patch comprises a feed source monopole patch, a rectangular reflector, a concave reflector, a plurality of pairs of open resonant rings and a grounding plate; the signal end of the microstrip feeder line is connected with the feed source monopole patch, and the ground end of the microstrip feeder line is connected with the ground plate; a concave reflector is arranged on the left side of the monopole patch, and a rectangular reflector is arranged on the substrate surface on the back of the concave reflector; pairs of split ring resonators are loaded symmetrically along the endfire direction.

2. The novel end-fire antenna based on the split resonant ring as claimed in claim 1, wherein: the dielectric substrate is FR4 dielectric substrate.

3. The novel end-fire antenna based on the split resonant ring as claimed in claim 1 or 2, wherein: the antenna adopts six pairs of symmetrical split resonant rings.

4. The novel end-fire antenna based on the split resonant ring as claimed in claim 1, wherein: the top of the feed source monopole patch is provided with a rectangular groove.

5. The novel end-fire antenna based on the split resonant ring as claimed in claim 1, wherein: the concave surface of the concave reflector is arc-shaped.

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