RU2327263C2 - Single-layer microstrip antenna - Google Patents

Abstract

FIELD: radio engineering.

SUBSTANCE: invention relates to antenna engineering, namely, to single-layer microstrip antennas intended to be used in SDMB frequency range. Concept of the invention is that single-layer microstrip antenna comprises 1) base, 2) emitter in the form of ring or polygon, and 3) feed strip, separated from emitter by a constant value interval; emitter and feed strip are located at the antenna base. Thickness of single-layer microstrip antenna base can be from 1 mm to 1.9 mm. Single-layer microstrip antenna can have a chip resistor for impedance match.

EFFECT: providing optimal circular polarisation at minimal size.

8 cl, 26 dwg, 2 tbl

Description

Field of Invention

The present invention relates to the field of a single-layer microstrip antenna, and more particularly, to the field of a single-layer microstrip antenna for use in the SDMB (Satellite Digital Multimedia Broadcasting) frequency range.

State of the art

The need for light, thin and inexpensive antennas designed for use in mobile electronic devices and vehicles has led to the development of antenna elements based on microstrip technology.

There are well-known circular-polarized microstrip antennas that are manufactured as bimodal fragments. These antennas have high-quality circular polarization in a fairly narrow frequency band. For wider frequency bands, multilayer antennas are made on a thick base, which leads to a significant increase in their size and, thus, to complicate production and increase production costs. This case is described in J.R. James, P. S. Hall. Handbook of Microstrip Antennas, Peter Peregrinus Ltd., London, UK, 1989.

Printed antennas, which are based on a traveling-wave ring resonator, also have high-quality circular polarization, but in a wider frequency band. Capacitively coupled antennas of this type are described in US Pat. No. 4,554,549 dated November 19, 1985 to Microstrip antenna with circular ring. An even higher quality of circular polarization was obtained by using a directional connector in the antenna to power the ring resonator. A known antenna of this type was realized only with the use of multilayer thick bases. [Links: VMBogod, VNDiki, DVKorolkov, VESorel "Multiwave radiator, based on traveling wave resonator with unified phase center for use in astronomy" ), Astrophysics researches, 1983, 17; D.V.Diki "Printed Antennas Based on Traveling Wave Resonators". Proceedings of JINA-98, Nice, France, November, 1998.

Thus, there is the problem of obtaining optimal circular polarization with a minimum antenna size.

Disclosure of invention

In accordance with the first aspect of the present invention, the solution of this problem is achieved by creating a single-layer microstrip antenna having a minimum thickness while maintaining compliance with the requirements of the operating conditions (G _RHCP ≥2.5 dBi in the required range, working bandwidth Δf = 25 MHz).

A second aspect of the present invention is to provide a single layer antenna, which also includes a frame resistor connected to one end of the supply strip to match the impedance.

The length of the perimeter of the emitter is essentially equal to the wavelength of the radio frequency.

The length of the supply strip is approximately equal to a quarter of the wavelength of the radio frequency.

The supply strip excites current in the emitter through the gap due to electromagnetic coupling.

Changing the gap length leads to a change in polarization and antenna bandwidth.

One end of the supply strip is connected to the coaxial line, the other end of the supply strip is free.

The base consists of a dielectric material, the thickness of the base is approximately 1 mm to 1.9 mm.

The gap between the supply strip and the radiator remains unchanged.

The radio frequency is within the SDMB frequency range.

Brief Description of Drawings

The aforementioned features and advantages of the present invention will become apparent from the following description, which contains references to the accompanying drawings describing certain exemplary embodiments of the present invention. In the drawings:

1 shows a single layer microstrip antenna according to a first embodiment of the present invention;

figure 2 shows a single-layer microstrip antenna according to the second embodiment of the present invention;

on figa-3C shows the measurement results for the antenna according to option 1.2.1;

on figa is a diagram describing the right circular polarization (RHCP) of the antenna according to option 1.2.1, on figv is a diagram describing the parameter S11 of the antenna according to option 1.2.1, on figs is a diagram describing the transverse polarization of the main lobe antennas according to option 1.2.1.

On figa-4B shows the simulation results for the antenna according to option 1.2.1.

On figa shows graphs of parameters S11 and S21 for the antenna according to option 1.2.1. Parameter S21 reflects the insertion loss between the input of the antenna and the output of the connector loaded with a resistance of 50 Ohms. On figv depicts radiation patterns of the antenna according to option 1.2.1.

On figa-5D shows the results of modeling electromagnetic fields in graphical form for the antenna according to option 1.2.2. Fig. 5A shows a graph of the parameter S11 for the antenna according to option 1.2.2, Fig. 5B shows the gain (RHCP) diagram for the antenna according to option 1.2.2, Fig. 5C shows the transverse polarization of the main lobe of the antenna according to 1.2.2, fig.5D shows the radiation patterns of the antenna according to option 1.2.2.

On figa-6D shows the results of modeling electromagnetic fields in graphical form for the antenna according to option 1.2.3, figure 6E shows the experimental test results of the antenna according to option 1.2.3. On figa shows graphs of parameters S11 and S21 for the antenna according to option 1.2.3. Parameter S21 reflects a decrease in the transfer coefficient between the antenna input and the output of the connector, loaded with a resistance of 50 Ohms. On figv shows the gain (RHCP) of the antenna according to option 1.2.3 obtained in the simulation, on figs shows the transverse polarization of the main lobe of the antenna according to option 1.2.3, on fig.6D shows radiation patterns of the antenna according to option 1.2.3 , FIG. 6E shows the measured antenna gain (RHCP) according to embodiment 1.2.3.

On figa-7D shows the results of modeling electromagnetic fields in graphical form for the antenna according to option 1.2.4, Fig.7E-7F shows the experimental results of testing the antenna according to option 1.2.4. Fig. 7A is a graph of the antenna parameter S11 according to embodiment 1.2.4; Fig. 7B shows the antenna gain according to embodiment 1.2.4 obtained from the simulation; Fig. 7C shows the transverse polarization of the main antenna lobe according to embodiment 1.2.4 obtained from simulation, Fig.7D shows radiation patterns of the antenna according to option 1.2.4.

FIG. 7E is a graph of the measured antenna gain according to embodiment 1.2.4; FIG. 7F is a graph of the measured antenna parameter S11 according to embodiment 1.2.4.

On figa and 8B shows the results of modeling electromagnetic fields in graphical form for the antenna according to option 1.2.5. On figa shows graphs of parameters S11 and S21 for the antenna according to option 1.2.5, on figv shows radiation patterns of the antenna according to option 1.2.5.

On figa and 9B shows the results of the simulation of electromagnetic fields in graphical form for the antenna according to option 1.2.6. On figa shows a graph of the parameter S of the antenna according to option 1.2.6, figv shows radiation patterns of the antenna according to option 1.2.6.

The implementation of the invention

The following describes exemplary embodiments of the present invention with reference to the accompanying drawings.

1 shows a single layer microstrip antenna according to an embodiment of the present invention.

The single layer microstrip antenna 100 according to the embodiment of the present invention shown in FIG. 1 includes a dielectric base 10, a supply strip 20, and an emitter 30.

The dielectric base 10 is a single layer of material metallized on both sides, and the area of the dielectric base 10 is preferably 38 × 38 mm ² . In addition, the thickness of the dielectric base 10 in an exemplary embodiment of the present invention should be from 1 mm to 1.9 mm. The base thickness t = 1 mm is the maximum permissible thickness if the antenna must meet the parameters of the requirements of the operating conditions (sensitivity G = 2.5 dBi, operating frequency Δf = 25 MHz). However, it is preferable that the thickness of the dielectric base 10 can be increased to 1.3 mm, taking into account that technological errors can occur during the manufacturing process of the antenna, affecting the antenna parameters to a critical degree.

The dielectric base 10 consists of a base material FLAN or a base material RO3003, which is a dielectric material manufactured by Rogers Corporation (Chandler, Arizona). The relative dielectric constant (ε) of the FLAN base is 3.8, the tangential loss (tan δ) of the FLAN base is approximately 0.0012; the relative dielectric constant (ε) of the base RO3003 10 is 3.0, the tangential loss (tan δ) of the base RO3003 is approximately 0.0013.

The formed feed strip 20 consists of metal material and is located on the upper side of the dielectric base 10. One end of the feed strip 20 is connected to the coaxial cable via a microstrip connector 40, the other end of the feed strip 20 is free. Preferably, the length of the feed strip 20 is from λ / 4 to λ.

The supply strip 20 is separated from the emitter 30 by a certain gap formed on the dielectric base 10. The supply strip 20 excites currents in the emitter 30 due to electromagnetic coupling through the gap.

In order to improve the characteristics of the electromagnetic coupling between the supply strip 20 and the emitter 30, the gap between the supply strip 20 and the emitter 30 in the communication region 50 preferably remains constant. If the gap remains constant, the shape of the supply strip 20 is most likely to be similar or similar to the shape of the emitter 30, as shown in FIG.

If the emitter 30 has an annular shape, the gap between the supply strip 20 and the emitter 30 should preferably remain constant to improve the electromagnetic coupling performance. Thus, the shape of the feed strip 20 in the communication region 50 should preferably be circular.

The emitter 30, formed on a dielectric base 10, has the shape of an octagonal ring with an empty center. The emitter 30 can be not only an octagonal ring, but also a circular or polygonal ring. The perimeter length of the emitter 30 is equal to or approximately equal to one wavelength λ of the radio frequency of the reception and transmission. Formed emitter 30 consists of a metal material.

The circular polarization and broadband characteristics of the antenna 100 can be improved by changing the gap, i.e. the distance between the emitter 30 and the feed strip 20.

Table 1 summarizes the main parameters of a single layer microstrip antenna 100 according to a first embodiment of the present invention. The single-layer microstrip antenna 100, the parameters of which are given in Table 1, has a FLAN base (ε = 3.8, tan δ = 0.0012) 38 × 38 mm2 in size and 1.9 mm thick.

Figure 2 shows a single-layer microstrip antenna according to another embodiment of the present invention.

In a single-layer microstrip antenna 200 according to another embodiment of the present invention shown in FIG. 2, one end of the supply strip 120 is connected to a frame resistor 160 for impedance matching, unlike the design of the antenna 100 shown in FIG. 1, in which the end of the supply strip is free. The resistance of the housing resistor 160 in the exemplary embodiment is 50 Ohm [Ω].

The frameless resistor 160 somewhat reduces the circular polarization characteristic of the antenna 200, but increases the impedance matching characteristic of the antenna 200 in a wide frequency band. The circular polarization characteristic of the antenna 200 can be increased by changing the gap between the emitter 130 and the feed strip 120 or the length of the feed strip 120.

With a frame resistor 160, the manufacturing costs of the antenna 200 according to the second embodiment of the present invention become higher compared to the antenna 100 according to the first embodiment of the present invention, but the transverse polarization parameters of the antenna 200 according to the second embodiment of the present invention are superior to the transverse polarization parameters of the antenna 100 according to the first an embodiment of the present invention.

Table 1 summarizes the main characteristics of a single layer antenna according to the present invention.

Table 1 Variable design parameters Antenna Specifications for the specified band 25 MHz 2.5 dBi gain band Option t mm Load presence E Casing RHCP gain (min. Over the entire band) Petal Width at 3 dB Transverse polarization of the main lobe Return radiation S11 dBi degrees Db Db Db MHz 1.2.1 *) 1.9 + 3.8 - 4.0 95 -26 -7.5 -13 62 1.2.2 1.9 - 3.8 - 4.4 96 -12 -7.5 -16 65 1.2.3 *) 1.27 + 3.0 + 3.2 93 -19 -8.4 -13 38 1.2.4 *) 1.27 - 3.0 + 3.3 93 -8.5 -7.9 -17 40 1.2.5 1.0 + 3.0 + 2.3 93 -8.1 -8.1 - 22 13.5 1.2.6 1.0 - 3.0 + 2.3 93 -9 -7.6 -eleven 22

In table 1, the parameter t denotes the thickness of the base. The base area is 38 × 38 mm ² . The emitter, the supply strip, the metal coating on the opposite side of the base are made of copper and have a thickness of 0.017 mm. The antenna cover, if placed on the surface of the base, is made of polystyrene (ε = 2.6). The base material used is FLAN (ε = 3.8, tang. Δ = 0.0012) or RO3003.

Table 2 shows the main characteristics of a single-layer antenna according to option 1.

table 2 Options*) Measured By model Gain RHCP (min.), DBi 3.6 (minimum) 4.0 The width of the petal, degrees one hundred 95 Transverse polarization of the main lobe, dB -twenty -26 Back radiation, dB -8 -7.5 S11, dB -13 -13

All parameters of the antenna 100 in table 2 are given for a bandwidth of 25 MHz.

On figa-3C shows the measured results for the antenna according to option 1.2.1.

On figa shows a diagram describing the gain (RHCP) of the antenna according to option 1.2.1, on figv is a diagram describing the parameter S11 of the antenna according to option 1.2.1, on figs is a diagram describing the transverse polarization of the main lobe of the antenna according to option 1.2.1.

On figa-4B shows the results for the antenna according to option 1.2.1 obtained in the simulation.

On figa shows graphs of parameters S11 and S21 for the antenna according to option 1.2.1. Parameter S21 reflects the insertion loss between the input of the antenna and the output of the connector loaded with a resistance of 50 Ohms.

FIG. 4B shows radiation patterns of an antenna according to embodiment 1.2.1.

On figa-5D shows the results of modeling electromagnetic fields in graphical form for the antenna according to option 1.2.2.

FIG. 5A is a graph of the parameter S11 for the antenna according to embodiment 1.2.2, FIG. 5B is a gain (RHCP) diagram of the antenna according to embodiment 1.2.2, FIG. 5C shows the transverse polarization of the main antenna lobe according to 1.2.2, FIG. .5D shows radiation patterns of the antenna according to option 1.2.2.

On figa-6D shows the results of modeling electromagnetic fields in graphical form for the antenna according to option 1.2.3, figure 6E shows the experimental test results of the antenna according to option 1.2.3.

On figa shows graphs of parameters S11 and S21 for the antenna according to option 1.2.3. Parameter S21 means a reduction in the transfer coefficient between the antenna input and the output of the connector loaded with a 50 Ohm resistor.

FIG. 6B shows a gain graph (RHCP) of an antenna according to embodiment 1.2.3 obtained by simulation, FIG. 6C shows the transverse polarization of the main lobe of the antenna according to embodiment 1.2.3, FIG. 6D shows radiation patterns of the antenna according to embodiment 1.2. 3, FIG. 6E is a gain graph (RHCP) of an antenna according to embodiment 1.2.3.

On figa-7D shows the results of modeling electromagnetic fields in graphical form for the antenna according to option 1.2.4, Fig.7E-7F shows the experimental results of testing the antenna according to option 1.2.4.

On figa shows a graph of parameter S11 for the antenna according to option 1.2.4, on figv shows a graph of the gain of the antenna according to option 1.2.4 obtained in the simulation, on figs shows a graph of the transverse polarization of the main lobe of the antenna according to option 1.2.4 obtained in the simulation, Fig.7D shows the radiation patterns of the antenna according to option 1.2.4.

Fig. 7E shows the results of measuring the antenna gain according to option 1.2.4; Fig. 7F shows a graph of the measured parameter S11 for the antenna according to option 1.2.4.

On figa and 8B shows the results of modeling electromagnetic fields in graphical form for the antenna according to option 1.2.5.

In particular, on figa graphs of parameters S11 and S21 for the antenna according to option 1.2.5 are shown, on figv radiation patterns of the antenna according to option 1.2.5 are shown.

On figa and 9B shows the results of the simulation of electromagnetic fields in graphical form for the antenna according to option 1.2.6.

In particular, FIG. 9A shows the antenna parameter S according to embodiment 1.2.6; FIG. 9B shows radiation patterns of the antenna according to embodiment 1.2.6.

As described above in exemplary embodiments of the present invention, a single-layer microstrip antenna has a thin, flat base made using microstrip technology. When using edge power, no additional antenna thickness is required. Consequently, the feeder can be easily connected to a flexible cable (coaxial or flat cable). Therefore, the single-layer microstrip antenna according to the embodiments of the present invention has a minimum thickness while maintaining compliance with the requirements of the operating conditions (G _RHCP ≥2.5 dBi in the desired range, operating bandwidth Δf = 25 MHz).

The above exemplary embodiments and aspects of the invention are merely exemplary and should not be construed as limiting the claimed scope of protection. The principles described can be directly applied to other types of devices. In addition, the description of exemplary embodiments of the present invention is intended to illustrate and not limit the scope of the claims; A person skilled in the art will recognize many of its alternatives, modifications, and variations.

Claims (8)

1. The antenna, which includes the following components: base; a ring or polygon shaped radiator formed on the base; formed on the basis of the supply strip, separated from the emitter by a gap of a predetermined constant value, which excites current in the emitter through the specified gap due to electromagnetic coupling, and the shape of the supply strip is similar or similar to the shape of the emitter. 2. The antenna according to claim 1, characterized in that it further includes a frame resistor connected to one of the ends of the supply strip to match the impedance. 3. The antenna according to claim 1, characterized in that the length of the perimeter of the emitter is essentially equal to the wavelength of the radio frequency. 4. The antenna according to claim 1, characterized in that the length of the supply strip is essentially equal to one quarter of the wavelength of the radio frequency. 5. The antenna according to claim 1, characterized in that the change in the length of the gap leads to a change in the polarization characteristics and the antenna bandwidth. 6. The antenna according to claim 1, characterized in that one end of the supply strip is connected to the coaxial line, and the other end of the supply strip is free. 7. The antenna according to claim 1, characterized in that the base consists of a dielectric material, and the thickness of the base is essentially from 1 to 1.9 mm 8. The antenna according to claim 4, characterized in that the radio frequency falls within the frequency range of SDMB.

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