RU164860U1 - DIRECTED DIRECTOR ANTENNA - Google Patents

Abstract

An omnidirectional director antenna, consisting of one active loop vibrator in the form of a conductor coil having a shape of a rectangle with rounded corners, the length of the larger side of which is about half the length of the electromagnetic wave, open in the middle of one larger side and connected at the break points to the power line, and many passive vibrator directors in the form of segments of a conductor having a length less than the length of the large side of the active vibrator located parallel to them so that the midpoints b of the larger sides of the active and passive vibrators-directors are in the same plane, characterized in that the passive vibrators-directors are located so that their midpoints are located along circles whose center coincides with the center of the active vibrator, at the same distance from the midpoints along the arc of a circle neighboring passive vibrators-directors, while the lengths of passive vibrators-directors belonging to one circle are equal, and with an increase in the radius of the circle on which the midpoints are located passive vibrator directors, the lengths of passive vibrator directors remain the same, and at least three passive vibrator directors are located on each circle.

Description

The utility model is intended for use as part of radio engineering devices of television, broadcasting and radio communications in the decameter, meter, decimeter and centimeter wave ranges. A known antenna with a controlled radiation pattern [1], consisting of asymmetric vibrators with a length of about a quarter of the electromagnetic wavelength, mounted perpendicular to a flat conductive surface and connected to it via controlled p-i-n diodes. In such an antenna, the central vibrator is active and is driven by a coaxial cable. The remaining vibrators are passive and, when the diode is on, play the role of reflectors. Vibrators with a disabled diode are electrically transparent and have practically no effect on the resulting daylight rate. Due to this, radiation directed in two planes is formed, and the main lobe is deviated from the conducting plane by a certain angle. With all the diodes turned on, it is theoretically possible to obtain radiation omnidirectional in the same plane. However, in another plane it will not be focused and the gain will be low, since passive vibrators in this case screen the radiation of the central vibrator.

However, in the angle sector between the directors, partial compensation of the fields is possible, leading to irregularity of the radiation pattern.

The disadvantage of the antenna is the inability to form a circular radiation pattern in the same plane with an increased directional coefficient.

The technical result of the utility model is to increase the directional coefficient of the antenna with omnidirectionality in one of the planes.

To achieve this technical result, an omnidirectional director antenna is proposed, consisting of one active loop vibrator in the form of a coil of a conductor having the shape of a rectangle with rounded corners, the length of the larger side of which is about half the length of the electromagnetic wave, open in the middle of one larger side and connected at the break points to the power line, and many passive vibrator directors in the form of segments of the conductor having a length less than the length of the large side of the active a loop vibrator located parallel to them so that the midpoints of the large sides of the active and passive vibrator directors are in the same plane, while the passive vibrator directors are located so that their midpoints are located along circles whose center coincides with the center of the active loop -vibrator, at the same distance along the arc of a circle from the midpoints of adjacent passive vibrators, and the lengths of the passive directors-vibrators related to one circle are equal, and for each circle ditsya least three passive vibrators. As the radius of the circles along which the passive vibrators directors grows, that is, as the passive vibrators directors move away from the active loop vibrator, the lengths of the passive vibrators directors do not change.

To reduce the unevenness of the pattern in the proposed utility model, the directors are placed not along radial rays, but along diverging circles. Moreover, the number of directors on circles and their mutual displacements can be different. Due to the increase in the number of directors on a circle, the number of circles or the rotation of directors of one circle relative to directors of another circle, it is possible to partially focus radiation also in intermediate (relatively radial) directions. Due to this, the non-uniformity of the pattern in the plane perpendicular to the vibrators will decrease, and the shape of the pattern approaches a circular pattern and this leads to an increase in the directional coefficient of the antenna with omnidirectionality in one plane in a wider frequency band due to the rectangular shape of the active vibrator with rounded corners, the length is longer the side of which is about half the length of the electromagnetic wave, open in the middle of one larger side

In FIG. 1 shows an omnidirectional director antenna with an active vibrator in the form of a Pistolkors loop - vibrator.

The active antenna vibrator is a Pistolkors loop vibrator made in the form of a coil of a conductor 1 having the shape of a rectangle with rounded corners, the length of the large sides of which is about half the length of the electromagnetic wave. One of the large sides of the loop opens in its middle. At break points 14 and 15, the conductor loop is connected to the power line.

In this case, the passive vibrator directors 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 and 13 are located on circles whose centers coincide with each other and with the active vibrator 1. The distances between adjacent passive vibrators -directors 2 and 3, 3 and 4, 4 and 5, 5 and 2, located on the smaller circle are equal. Also equal are the distances between the passive vibrator directors 6 and 7, 7 and 8, 8 and 9, 9 and 10, 10 and 11, 11 and 12, 12 and 13, 13 and 6, located on a larger circle.

The lengths of directors 2, 3, 4, and 5 are equal to each other. The lengths of directors 6, 7, 8, 9, 10, 11, 12, and 13 are also equal. The lengths of directors 6, 7, 8, 9, 10, 11, 12, and 13 are equal to the lengths of directors 2, 3, 4, and 5

Omnidirectional director antenna works as follows.

When the power is connected at points 14, 15 to the active vibrator 1, a standing current wave forms in it, and the active vibrator starts emitting electromagnetic waves. Since the length of the active vibrator is close to half the length of the electromagnetic wave, the maximum radiation is oriented normal to the axis of the active vibrator.

The electromagnetic field of the active vibrator excites currents in the passive vibrator directors 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 and 13, setting in motion the available free electrons in them. The length of the passive vibrator directors is less than the length of the active vibrator, so they also generate a standing current wave. As a result, the passive director vibrators create secondary electromagnetic waves, the maximum radiation intensity of which falls on the direction perpendicular to the axis of the vibrators.

The length of the passive vibrator directors 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 and 13 is less than the length of the active vibrator 1. Due to this, the capacitive resistance of the passive vibrator directors is achieved, and therefore , the current in the passive vibrator directors lags behind the current in the active vibrator.

The field of the omnidirectional director antenna in the far zone is a superposition of the primary and secondary electromagnetic fields created by the active vibrator 1 and passive vibrator directors 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, respectively. In the plane perpendicular to the passive vibrator directors, in the direction from the active vibrator 1 to any of the passive vibrator directors, for example 2, the phase shifts obtained by the fields as a result of the passage of distances from one vibrator to another will be compensated by phase shifts arising from the difference phases between currents in vibrators 1 and 2, 1 and 3, 1 and 4, etc. As a result, all fields will be added in phase. By virtue of symmetry, this situation will take place in the direction of any of the passive vibrator directors. However, in the angle sector between passive directors, partial field compensation is possible, resulting in irregular patterns.

Due to the mutual influence of active 1 and passive vibrator directors 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and 13, the input impedance of the active vibrator may be low, which makes it difficult to coordinate with the power line. Since the directivity pattern of a loop vibrator is the same as that of an active vibrator in the form of a conductor section, a directional antenna with an active vibrator in the form of a Pistolkors loop vibrator has the same directivity as an omnidirectional directional antenna with an active symmetrical half-wave vibrator.

In a plane passing through an active vibrator, an omnidirectional director antenna works like a wave channel antenna. In the direction perpendicular to the vibrators 1 and 2, 1 and 3, 1 and 4, etc. the primary and secondary fields of such passive vibrators add up in phase, which leads to an increase in directivity in the plane in question compared to a single active vibrator 1.

The performance of the proposed omnidirectional antenna is confirmed by the results of computer simulation of this antenna in the MMANA-GAL Pro 2.5.5.30 program:

- FIG. 2 is a radiation pattern of an antenna with 4 passive vibrators directors (Fig. 2, active vibrator 1 and passive vibrators directors 2, 3, 4, 5) in a plane perpendicular to the vibrators (in the omnidirectional plane);

- FIG. 3 is a radiation pattern of an antenna with 4 passive vibrator directors (Fig. 2, active vibrator 1 and passive vibrator directors 2, 3, 4, 5) in a plane passing through the active vibrator;

- FIG. 4 is a radiation pattern of an antenna with 12 passive vibrators directors (Fig. 2, active vibrator 1, passive vibrators directors 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13) located along two circles, in a plane perpendicular to the vibrators (in the omnidirectional plane);

- FIG. 5 is a radiation pattern of an antenna with 12 passive vibrator directors (Fig. 2, active vibrator 1, passive vibrator directors 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13) located along two circles, in a plane passing through an active vibrator.

According to computer simulation, the gain in directional coefficient from the use of 4 passive directors-vibrators in comparison with a single vibrator is about 1.9 dB.

The proposed omnidirectional director antenna in the plane perpendicular to the vibrators, remains omnidirectional, and in the plane parallel to it, has an increased coefficient of directional action of the antenna compared to a single vibrator.

LITERATURE

1. Fedun I.V. Vibrator antenna of vertical polarization ... / Patent UA 88309 C2 of 12.10.2009

Claims (1)

An omnidirectional director antenna consisting of one active loop vibrator in the form of a conductor coil having a shape of a rectangle with rounded corners, the length of the larger side of which is about half the length of the electromagnetic wave, open in the middle of one larger side and connected at the break points to the power line, and many passive vibrator directors in the form of segments of a conductor having a length less than the length of the large side of the active vibrator located parallel to them so that the midpoints b of the larger sides of the active and passive vibrators-directors are in the same plane, characterized in that the passive vibrators-directors are located so that their midpoints are located along circles whose center coincides with the center of the active vibrator, at the same distance from the midpoints along the arc of a circle neighboring passive vibrators-directors, while the lengths of passive vibrators-directors belonging to one circle are equal, and with an increase in the radius of the circle on which the midpoints are located passive vibrator directors, the lengths of passive vibrator directors remain the same, and at least three passive vibrator directors are located on each circle.

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