RU2530242C1 - Antenna - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: antenna containing a square metal plate located above a metal screen parallel to it, differing by the fact that in the middle of sides of the square metal plate there are slots perpendicular to its sides, which are smaller as to length than half length of a side of the square metal plate; to opposite laying slots there in-phase connected are two pieces of equal length of a coaxial cable, which are parallel connected in a central area of the square metal plate; to their common point there connected is an input cable passing to the metal screen through the centre of the square metal plate; besides, installation height of the square metal plate above the metal screen lies in the limits up to half of its side.

EFFECT: enlarging a working width range, enlarging coefficient of directed action and amplification coefficient at reduction of overall dimensions.

2 cl, 4 dwg

Description

The invention relates to the field of antenna-feeder devices and can be used, for example, as a directional bipolarization antenna with orthogonal polarizations in the decimeter wavelength range.

A known antenna, the fabric of which is made of a metal sheet (RF patent No. 2256983 C2, H01Q 9/00), provides operation with one linear polarization. The operation of such an antenna simultaneously with two orthogonal linear polarizations is impossible.

A known antenna containing a square metal plate located above a metal screen parallel to it (D.M. Sazonov, Antennas and microwave devices, Higher School, Moscow, 1988, pp. 258-262, Fig. 10-15, 10-18 ) emitting a field of two orthogonal polarizations, selected as a prototype.

The disadvantages of the known antenna are its narrowband (bandwidth ~ up to 3% of the average frequency) and low efficiency (50 ÷ 80%).

The technical result of the proposal is that while maintaining the technological simplicity of flat, including printed, antennas, an extension of the operating frequency range is achieved, an increase in the directional coefficient and gain while reducing the overall dimensions without using high-frequency dielectrics.

The expected technical result is achieved by the fact that in the antenna containing a square metal plate located above the metal screen parallel to it, slots are made in the middle of the sides of the square metal plate, perpendicular to its sides, shorter than half the length of the side of the square metal plate, to opposite slots two segments of equal length of a coaxial cable connected in parallel in the central region of a square metal plate are connected in phase to their common ochke attached input cable extending to the metal screen through the center of a square metal plate, wherein the mounting height of a square metal plate does not exceed half the length of its sides over the metal screen.

In addition, in the antenna above the sides of the square metal plate, passive vibrators are installed on insulators parallel to them and symmetrically relative to the slots, the length of which is less than the length of the side of the square metal plate.

Figure 1 is a side view of the antenna according to claim 1;

Figure 2 is a top view of the antenna according to claim 1;

Figure 3 is a side view of the antenna according to claim 2;

Figure 4 is a top view of the antenna according to claim 2.

Designations in the figures:

1 - square metal plate;

2 - input cables;

3 - metal screen;

4 - pieces of coaxial cable;

5 - slots;

6 - rack insulators;

7 - rack-insulators of passive vibrators;

8 - passive vibrators;

9 - sectors of a square metal plate;

10 - metal rack.

s is the width of the slots 5;

H is the height of the square metal plate 1 above the metal screen 3;

h is the height of the passive vibrators 8 over a square metal plate 1;

a is the side length of the square metal plate 1;

b is the length of the slots 5;

e is the width of the passive vibrators 8;

g is the length of the passive vibrators 8;

C is the distance of the point of attachment of the segments of the coaxial cable 4 from the edge of the square metal plate 1.

A square metal plate 1, in which slots 5 are made, the width of which S is much less than the wavelength of the working wave, is mounted, for example, on the insulator racks 6 above the metal screen 3. On the square metal plate 1, segments of the coaxial cable 4 are secured with electrical contact, central the conductors of which are connected to opposite sides of the slots 5. Also, on the surface of the square metal plate 1, input cables 2 are connected to the point of parallel connection of the segments to axial cable 4. Input cables 2 are output from a square metal plate 1 through its center (point of zero potential) to the metal screen 3.

A square metal plate 1 can be mounted on one metal rack 10 located in its center (Fig. 3), instead of the insulator racks 6 (Fig. 1).

Above the sides of the square metal plate 1 parallel to them and symmetrically relative to the slots 5, passive vibrators 8 are additionally mounted on the insulator racks 7 (Fig. 3, Fig. 4).

When the antenna is operating, the input signal is supplied to the input cables 2 and through the segments of the coaxial cable 4 in-phase excites opposite slots 5 and through them the currents on the sectors of the square metal plate 9, emitting energy into space. In this case, the square metal plate 1 resonates at the lower frequencies of the input signal, and its sectors 9 at high frequencies. The resonant size of the square metal plate 1 is reduced from the introduction of the slots 5 compared with the resonant size of the plate of the prototype, equal to half the length of the working wave.

Further improvement in matching the antenna with the input cable and increasing its gain at the higher frequencies of the operating range is achieved by introducing passive vibrators 8. Their length should be less than the length of the side of the square metal plate 1, because they should resonate at higher frequencies than a square metal plate.

By choosing a height within the specified limits, broadband is simultaneously achieved by matching the antenna with the input cable and a high gain. Exceeding the height leads to an expansion of the radiation pattern and a decrease in gain.

To obtain optimal antenna characteristics in a given frequency range, the antenna dimensions must be made within the following limits:

;a = (0.28-0.35) λ _max ; $$h<\frac{\lambda \max }{\mathrm{four}}$$

;

s << λ _max ; e << λ _max ; b <0.45a; c <0.5b;

Where

s is the width of the slots 5;

λ _max - the length of the maximum working wave;

a is the side length of the square metal plate 1;

h is the height of the passive vibrators 8 over a square metal plate 1;

b is the length of the slots 5;

e is the width of the passive vibrators 8;

g is the length of the passive vibrators 8;

C is the distance of the point of attachment of the segments of the coaxial cable 4 from the edge of the square metal plate 1.

The experiments showed that the working range of the proposed antenna is expanded to 30% or more.

When performing the antenna using passive vibrators 8, the working range of the antenna is further expanded and can be brought up to double, in which the ratio of the upper operating frequency to the lower is at least 2.

Claims (2)

1. An antenna containing a square metal plate located parallel to it above the metal screen, characterized in that, in the middle of the sides of the square metal plate, slots are made perpendicular to its sides, shorter in length than half the length of the side of the square metal plate, are connected in phase to the opposite slots two segments of equal length of a coaxial cable connected in parallel in the central region of a square metal plate, an input cable is connected to their common point Extending the metal screen through the center of a square metal plate, wherein the mounting height of a square metal plate above the metal screen is in the range up to half of its sides. 2. The antenna according to claim 1, characterized in that passive vibrators are installed on insulators parallel to them and symmetrically relative to the slots on the insulators, the length of which is less than the length of the side of the square metal plate.

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