CN209880806U - A Square Helical Antenna with Helical Slots - Google Patents

Abstract

The utility model provides a square six-arm slot helical antenna, which comprises an antenna main body, wherein a feed network of the antenna is connected with N helical arm units which are parallel to each other; the spiral arm unit extends spirally towards the direction far away from the grounding plate; the overlooking direction of the spiral surface of the spiral arm unit is rectangular; the spiral surface of each spiral arm unit is formed by bending the spiral arm unit four times, and the bending angles of the spiral arm units are the same each time so as to excite circular polarization waves to realize the circular polarization of the antenna; the utility model discloses do not need the electric bridge, with low costs, functional, simple structure, small in size, be fit for using in satellite navigation terminal navigation equipment.

Description

A Square Helical Antenna with Helical Slots

technical field

The utility model relates to the technical field of antennas, in particular to a square six-arm slot helical antenna.

Background technique

With the rapid development of wireless communication technology, antennas, as an indispensable component in various wireless communication devices, have been widely used and made important technological progress.

Directional antenna refers to an antenna that transmits and receives electromagnetic waves particularly strongly in one or several specific directions, while transmitting and receiving electromagnetic waves in other directions is zero or extremely small. The purpose of using a directional transmitting antenna is to increase the effective utilization of radiation power and increase confidentiality; the main purpose of using a directional receiving antenna is to enhance signal strength and increase anti-interference ability.

In many radar systems, navigation systems, satellite systems, and remote control telemetry systems, circularly polarized antennas are a commonly used antenna form. Circularly polarized antennas are beneficial to the reception of space electromagnetic waves, and can also suppress the interference of rain and fog reflection clutter. It is of great practical significance to carry out research on low-cost, miniaturized, and low-profile circularly polarized antennas.

Nowadays, Global Navigation Satellite System (GNSS) plays an important role in daily military, civilian and commercial applications, and a circularly polarized antenna with good performance and good directionality is the key to these applications.

The traditional quadrifilar helical antenna has been widely used due to its excellent performance. With the rapid development of satellite communication and navigation technology, the market has higher and higher requirements for antenna products. Traditional helical antennas must be equipped with complex bridges and are not easy to miniaturize. Therefore, a new type of helical antenna must be proposed to simplify and miniaturize the antenna structure while ensuring the performance of the antenna.

Contents of the invention

The utility model proposes a square six-arm slot helical antenna, which does not need an electric bridge, has low cost, good performance, simple structure and small size, and is suitable for use in satellite navigation terminal navigation equipment.

The utility model adopts the following technical solutions.

A square six-arm slot helical antenna, comprising an antenna main body (1), the feed network (6) of the antenna is connected to N mutually parallel helical arm units (2); the helical arm units move away from the ground plate ( 4) extends spirally in the direction of the spiral arm unit; the top view of the helical surface of the helical arm unit is rectangular; the helical surface of each helical arm unit is formed by bending the helical arm unit four times, and the angle of each bending is the same to excite the circular pole The wave is used to realize the circular polarization of the antenna.

The spiral arm units have a slit structure, and each spiral arm unit is located at the wall of a metal rectangular cylinder; the length of each spiral arm unit is the same, the rotation direction is the same, and the distance between each spiral arm unit is the same.

The N is six, and the helical surface of each helical arm unit is a slotted gap provided on the wall of the rectangular cylinder.

Each spiral arm unit bends upwards and the upward inclination angle preferably ranges from 15° to 30°.

The feed network includes a feed line that is bent at the lower part of the rectangular cylinder wall and extends to the upper surface of the ground plate, and the feed input end (31) of the feed network is located at the ground plate at the bottom of the rectangular cylinder Line (7) is connected to excitation port (51).

The grounding plate is a grounding plate with a thickness ranging from 0.5mm to 2mm; the metal strip width of the feed network is 1-2.5mm.

A bent and formed annular reflective patch (52) is provided on the lower surface of the grounding plate; the outer edge of the reflective patch is in contact with the gap of the patch.

The resonance frequency of the antenna can be adjusted by adjusting the length of the helical arm unit.

The resonant frequency of the antenna is located in the GPSL1 receiving frequency band of the Global Positioning System, or in the receiving frequency band B1 of the Beidou Satellite Navigation System BDS.

The antenna adopts coupling feeding, and the size of the antenna is preferably 23mm*23mm*53mm.

Compared with the prior art, the utility model has the following advantages: the utility model adopts grooves on the metal surface instead of traditional metal strips, and can effectively realize broadband and antenna directivity. Compared with the traditional helical antenna, it does not need complex electric bridges, and the antenna structure is simpler. The main body of the helical antenna and the bent-shaped feeding network structure are all built on the Lianmao IT-8350G board. The cost of the antenna is low and Easy to manufacture. The size of the antenna is preferably 23mm*23mm*53mm. The antenna has good performance, simple structure and small size, and is suitable for use in satellite navigation terminal equipment.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail:

FIG. 1 is a perspective view of a slot helical antenna;

Figure 2 is a front view of the slot helical antenna;

Figure 3 is a top view of the slot helical antenna;

Figure 4 is a schematic diagram of the plane expansion of Figure 1;

FIG. 5 is a schematic diagram of the lower surface of the ground plate at the bottom of the slot helical antenna;

Fig. 6 is the simulation result graph of the reflection coefficient of the slot helical antenna;

Fig. 7 is the circular polarization axial ratio bandwidth simulation result diagram of the slot helical antenna;

Figure 8 is a right-handed square diagram of the slot helical antenna;

Fig. 9 is a left-handed square diagram of the slot helical antenna;

In the figure, 1. Antenna main body, 2. Spiral arm unit, 3. Rectangular tube, 4. Ground plate, 5. Air layer, 6. Feed network, 7. Coaxial cable, 31. Feed input terminal, 51, Excitation port, 52, annular reflection patch, 53, patch gap.

Detailed ways

As shown in Figures 1-9, a square six-arm slot helical antenna includes an antenna main body 1, and the feed network 6 of the antenna is connected to N spiral arm units 2 that are parallel to each other; The direction of the floor 4 extends spirally; the top view of the helical surface of the helical arm unit is rectangular; the helical surface of each helical arm unit is formed by bending the helical arm unit four times, and the angle of each bending is the same to excite the circular pole The wave is used to realize the circular polarization of the antenna.

The spiral arm units have a slit structure, and each spiral arm unit is located at the wall of a metal rectangular cylinder; the length of each spiral arm unit is the same, the rotation direction is the same, and the distance between each spiral arm unit is the same.

The N is six, and the helical surface of each helical arm unit is a slotted gap provided on the wall of the rectangular cylinder.

An air layer 5 is provided at the gap of the slot; each spiral arm unit is bent upwards and the upward inclination angle preferably ranges from 15° to 30°.

The feed network includes a feed line that is bent at the lower part of the rectangular cylinder wall and extends to the upper surface of the ground plate. The feed input end 31 of the feed network is located at the ground plate at the bottom of the rectangular cylinder and passes through the coaxial line Connect to the excitation port 51.

The grounding plate is a grounding plate with a thickness ranging from 0.5mm to 2mm; the metal strip width of the feed network is 1-2.5mm.

The lower surface of the grounding board is provided with a bent and formed annular reflective patch 52 ; the outer edge of the reflective patch is in contact with the patch gap 53 .

The resonance frequency of the antenna can be adjusted by adjusting the length of the helical arm unit.

The resonant frequency of the antenna is located in the GPSL1 receiving frequency band of the Global Positioning System, or in the receiving frequency band B1 of the Beidou Satellite Navigation System BDS.

The antenna adopts coupling feeding, and the size of the antenna is preferably 23mm*23mm*53mm.

In this example, the antenna adopts the form of slotting on the outer surface of the medium to form six groups of helical arm unit gaps, and the feeding network is attached to the inner surface of the square tube medium, and the coupled feeding method is adopted, no bridge is needed, and the structure is simple , compact size.

In this example, the size of the antenna is 23mm*23mm*53mm, and the size of the bottom FR4 ground plate is 35mm*35mm*0.8mm.

The specific dimensions are: the thickness of Lianmao IT-8350G plate 3 is 0.5mm, the height of the helical antenna main body 1 is 53mm, the circumference of the helical antenna main body 1 is 92mm, the length of the six sets of helical arm unit 2 is 91mm, and the width is 3.2mm , the angle of upward inclination along the horizontal plane is 23°, the width of the bent feed network 6 is 1.5 mm, the radius of the coaxial line 7 is 0.45 mm, the radius of the excitation port 51 is 1.3 mm, and the lower surface of the bottom FR4 ground plate 4 The patch slit 52 of the bent annular reflective patch 52 has a slit width of 1 mm.

The rectangular cylinder is preferably formed by Lianmao IT-8350G plate; the ground plate is preferably formed by FR4 ground plate.

The preferred embodiments of the present utility model have been described above with reference to the accompanying drawings, and the scope of rights of the present utility model is not limited thereto. Any modifications, equivalent replacements and improvements made by those skilled in the art without departing from the scope and essence of the present invention shall fall within the scope of rights of the present invention.

Claims (10)

1. A square six-arm slot helical antenna, comprising an antenna main body (1), characterized in that: the feed network (6) of the antenna is connected to N mutually parallel helical arm units (2); the helical arm The unit spirally extends away from the grounding plate (4); the top view of the spiral surface of the spiral arm unit is rectangular; the spiral surface of each spiral arm unit is formed by bending the spiral arm unit four times, and each bending The angles are the same to excite circularly polarized waves to realize the circular polarization of the antenna. 2. A kind of square six-arm slot helical antenna according to claim 1, characterized in that: the helical arm unit is a slit structure, and each helical arm unit is positioned at a metal rectangular cylinder wall; The units have the same length and the same direction of rotation, and the spacing between the individual helical arm units is the same. 3 . The square helical antenna with six-arm slots according to claim 1 , wherein the N is six, and the helical surface of each helical arm unit is a slotted slot provided on the wall of the rectangular tube. 4 . 4. A square six-arm slot helical antenna according to claim 3, characterized in that each helical arm unit bends upwards and the upward inclination angle preferably ranges from 15° to 30°. 5. A square six-arm slot helical antenna according to claim 3, characterized in that: the feed network includes a feed line bent at the lower part of the wall of the rectangular cylinder and extended to the upper surface of the ground plate, feeding The feed input end (31) of the network is located at the grounding plate at the bottom of the rectangular cylinder and is connected to the excitation port (51) via the coaxial line (7). 6. A square helical helical antenna with six arms according to claim 5, characterized in that: the ground plate is a ground plate with a thickness ranging from 0.5 mm to 2 mm; the metal strip width of the feed network is 1 -2.5mm. 7. A square six-arm slot helical antenna according to claim 5, characterized in that: the lower surface of the ground plate is provided with a bent and formed annular reflective patch (52); the reflective patch The outer edge is in contact with the patch gap. 8 . A square helical helical antenna with six arms according to claim 5 , wherein the resonant frequency of the antenna can be adjusted by adjusting the length of the helical arm unit. 9. A square helical helical antenna with six arms according to claim 8, characterized in that: the resonant frequency point of the antenna is located in the GPSL1 receiving frequency band of the Global Positioning System, or in the receiving frequency band B1 of the Beidou Satellite Navigation System BDS. 10. A square helical helical antenna with six arms according to claim 8, characterized in that: the antenna adopts coupling feeding, and the size of the antenna is preferably 23mm*23mm*53mm.