RU188741U1 - Microstrip antenna with circular polarization - Google Patents

Abstract

The invention relates to radio engineering and can be used in radiolocation, radio navigation, communications, antenna systems and radio measurements, as an independent antenna, and as a basic radiating element in printed phased antenna arrays. The antenna contains a dielectric substrate, a slit, a radiator and a power line placed on it. In addition, three dielectric substrates were added, on which dipole emitters of identical form, supply lines and slots are located. Moreover, all the substrates are oriented mutually perpendicular to each other and are aligned with one side wall with each other. The technical result consists in the possibility of obtaining circular polarization. 4 il.

Description

The proposed microstrip antenna with circular polarization relates to radio engineering and can be used in radiolocation, radio navigation, communications, antenna systems and radio measurements, both as an independent antenna, and as a basic radiating element in printed phased antenna arrays.

Known ultra wideband antenna of circular polarization (Patent No. 2206160. "Ultra wideband antenna of circular polarization". IPC H01Q 21/24), which forms a field of radiation of circular polarization in the ultra-wide frequency band. The disadvantage of this antenna is the formation of a field of circular polarization in a small sector of angular directions.

Known dual-band microstrip antenna with circular polarization, containing a metal screen, two radiating elements in the form of square metal plates arranged one above the other parallel to the metal screen and separated by dielectric substrates, and a coaxial transmission line (coaxial feeder) with two excitation points [USSR USSR Certificate No. 1771016, IPC H01Q 1/38, publ. 10/23/1992]. To increase the bandwidth of the working frequencies and the scanning sector, according to the ellipticity factor, the plates have discontinuities in the form of slots cut from the corners of the plates along the diagonal and discontinuities in the form of protrusions designed to adjust the operating frequencies. However, the implementation of irregularities in the plates of this antenna complicates its manufacture.

Closest to the proposed antenna is a microstrip dipole antenna, the shoulders of a dipole are made on one side, and the feeding element in the form of a strip is made on the other side (Patent CLLJA N 3845490, cl. 343-821, 1974). However, the known antenna cannot work with circular polarization, which is especially important in antenna systems of meteorological radars for tracking upper-air radiosondes (ARZ) and meteorological rockets.

The utility model is aimed at obtaining circular polarization at the microstrip antenna. The technical result is the creation of a compact microstrip antenna with circular polarization.

The technical result is achieved due to the fact that identical antennas are added to the inventive microstrip antenna with circular polarization and thus it will consist of four identical dipole emitters aligned orthogonal to each other by one side wall. Power to the radiators can be supplied separately for each using coaxial cable or microwave connectors, or using a power divider. The signal divider input is the antenna input.

Microstrip antenna with circular polarization, containing a dielectric substrate, a slit, an emitter and a power line placed on it, characterized in that three dielectric substrates are additionally introduced, on which are located, dipole emitters, power lines and slots of identical shape, all of which are oriented mutually perpendicular to each other and aligned with one side wall with each other.

The invention is illustrated by the figures, which depict:

in fig. 1 - the preferred topology of the proposed microstrip antenna with circular polarization, implemented on a dielectric substrate with a relative dielectric constant of 4.4 and a thickness of 1 mm; where 1, 2, 3, 4 are antenna inputs, 5, 6, 7, 8 are microstrip resonators, 9, 10, 11, 12 are power lines;

in fig. 2 is a graph of the CWS versus frequency;

in fig. 3 is a graph of the gain versus frequency, expressed in decibels;

in fig. 4 is a graph of the radiation pattern at the center frequency (2100 MHz).

The microstrip dipole antenna of circular polarization has one 50-ohm input, a power divider for four outputs, 4 emitters with radiators, a power line and a slit. The number of emitters can be 2 ^N , where N is an integer greater than one.

The input signal is divided in the signal divider into four signals equally and without reflection. The signal from the first output enters the input of the first dipole emitter 1, which emits it in free space. The second, third and fourth dipole emitters 2, 3, 4 signals fall from the second, third and fourth output of the signal divider, respectively. With this arrangement, the two emitters emit a linear polarization signal into space, the second two rotated relative to the first ones at an angle of 90 degrees, also emit a linear polarization. However, due to the fact that the radiators are rotated by 90 degrees relative to the first pair, the field of circular polarization is obtained in total. All the resulting construction can be placed in a radio transparent case. Also at the bottom you can leave a gap of the required width for the power connection. It is necessary to ensure the absence of contacts of electrically conductive elements in all dipole antennas, thus avoiding distortion of the frequency characteristics of the entire antenna.

As a result of electromagnetic modeling of a microstrip antenna with circular polarization, it was possible to receive a signal in free space (far field). The data obtained as a result of electromagnetic modeling of the antenna, confirmed the receipt of circular polarization.

For the inventive antenna, the ellipticity coefficient calculated by the above method turned out to be equal to 0.84, which allows to conclude that the antenna in question has the ability to transmit and receive a signal with circular polarization.

The following specifications were also obtained:

The operating frequency band is 67%, in terms of the CWS = 2, in accordance with the data in FIG. 2;

the gain in the frequency band is not lower than 5 dB, in accordance with the data in FIG. 3

Claims (1)

Microstrip antenna with circular polarization, containing a dielectric substrate, a slit, an emitter and a power line placed on it, characterized in that three dielectric substrates are additionally introduced, on which dipole emitters of identical form, power lines and slots are located, all substrates are oriented mutually perpendicular to each other and aligned with one side wall with each other.

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