JPS63212204A - Printed dipole antenna - Google Patents

Abstract

PURPOSE:To suppress the level reduction at a wide angle by providing a metallic piece to the rear face of a split gap of a split non-exciting element and connecting two split non-exciting elements electrically through a capacitance formed depending on the thickness of the dielectric. CONSTITUTION:Plate dipoles 2a, 2b are provided to both faces of a dielectric plate 1 as a printed radiation part, a split non-exciting element 10 is provided as elements 10a, 10b at an interval (d) with two split to the radiation side from one dipole of the dielectric plate, and a printed metallic piece 11 is provided to the rear face of the gap of the split non-exciting element. The interval of the split non-exciting elements 10a, 10b is connected electrically via a capacitance to obtain the effect of low coupling to obtain the printed dipole antenna suitable for wide beam scanning.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printed dipole antenna to which a parasitic element is added in order to reduce mutual coupling between element antennas.

[Conventional technology]

Figure 5 is a structural diagram of a conventional printed dipole antenna, as shown in, for example, Antenna Engineering Handbook, edited by the Institute of Electronics and Communication Engineers, Ohmsha (1980-10), p. 42. In the figure, 1 is a dielectric plate. , 2a.

2b is a dipole, 3a and 3b are two parallel wires, and the dipoles 2a and 2b and the two parallel wires 3 and 3b are printed on both sides of the dielectric plate 1 by etching, sandwiching the dielectric. 4 is a reflection plate for single-sided radiation. 6th
The figure shows an example of the structure of a Guiball array constructed by arranging a plurality of printed dipole antennas 5 shown in Fig. 5. For simplicity, four printed dipole antennas are arranged with gaps. It shows the case. Here, the plane on which the radiation beam is scanned is the ZX plane (φ=O°).

Figure 7 is a diagram showing the configuration of the feeder circuit for the four-element Guibor array shown in Figure 6, where 5 is a printed dipole antenna, 6 is a phase shifter, 7 is a power divider, and 8 is a signal generator. .

In FIG. 7, in order to direct the radiation beam in the direction of θ0 in the ZX plane, the radio waves from the signal generator 8 are divided into four by the power divider 7, and the difference in θ0 due to the deviation in the relative position of each printed dipole 5 is The amount of phase shift of each phase shifter 6 may be set so that the phase difference in the direction is corrected and plane waves are synthesized in the same phase.

The relationship between the element spacing and the beam scanning angle θ0 is based on R, C, Hansen (R, C
, ) lansen), “Microwave Scanning Antenna J”
ingAntennas Volume I [, Acs
demic Press (1966)) p.
As shown in 17, it is chosen so that the following holds true. Here, λ is the wavelength of the radio wave. For example, when scanning the beam up to 60°, D< 0.536λ...(
2).

[Problem that the invention seeks to solve]

As shown in equation (2), when scanning the beam over a wide angle, it is necessary to narrow the element spacing to about 0.5 wavelength. However, in the case of such an element spacing, the amount of mutual coupling between the dipole antennas is large, that is, the radio waves incident from other elements become large, and the impedance during operation of the printed dipole antenna 5 increases as the beam scans. There was a problem that the radiation pattern with the desired beam shape and side lobe level could not be obtained due to the change in the radiation pattern.

Therefore, in order to reduce the amount of mutual coupling, there is a method of adding a parasitic element 9 in front of the dipoles 2a and 2b as shown in FIG. 8, but according to this, the beam width of the element pattern of the dipole antenna is There was a problem in that the level of the main beam of the array antenna decreased when scanning the beam to a wide angle. Furthermore, in order to prevent this level drop, there is a method of adding divided parasitic elements 10a and 10b divided at an interval d as shown in FIG. 9, but there is a problem that it is difficult to obtain the desired effect of reducing coupling. Ta.

This invention was made to solve the above-mentioned problems, and provides a printed dipole antenna that can reduce coupling by adding a simple metal piece and is suitable for wide-angle beam scanning. The purpose is to

[Means for resolving the gap-lighting point]

In the printed dipole antenna according to the present invention, a metal piece is provided on the back side of the dividing gap of the divided parasitic elements, and the two divided parasitic elements are electrically connected through the capacitance formed by the thickness of the dielectric. It is.

[Effect]

The dipole according to the present invention to which split parasitic elements with metal pieces are added can achieve a state that is electrically closer to that when 11 parasitic elements are added than when only split parasitic elements are added. The amount of mutual coupling becomes smaller.

〔Example〕

An embodiment of this invention will be described below. In Fig. 1, 1 is a dielectric plate, 2a and 2b are plate-shaped gui poles as a radiation part printed on both sides of the dielectric plate 1, 3a is two parallel wires that are a power feeding part, and lOa and 10b are dielectrics. This is a split parasitic element provided on the radiation side of the dipole on one side of the plate, and is divided into two parts with an interval d.

Reference numeral 11 denotes a metal piece printed on the back surface of the spaced portion of the divided parasitic elements. In this way, in this embodiment, the metal piece 1
1, the divided parasitic elements 10a, 10b
are electrically connected via capacitance. FIG. 2 is a diagram of this printed dipole antenna seen from the back side. FIG. 3 is a diagram showing the distribution shape of the current induced on the back surface of the parasitic element, and FIG. 4 is a diagram showing the radiation pattern of the printed dipole antenna.

Next, the effects will be explained.

The current distribution on the divided parasitic elements toa and 10b of the printed die-ball antenna shown in FIGS. 1 and 2 has the shape shown at 21 in FIG. 3(a). This current distribution 21 is composed of a mode A1 shown in FIG. 3(b), that is, a current distribution 22 of one parasitic element 9, and a mode B shown in FIG. 3(C).
That is, the divided parasitic element 10a.

This is a distribution obtained by superimposing the current distribution 23 in the case of only 10b.

FIG. 4 shows the radiation pattern in the H plane (ZX plane) for each current distribution, and 30 is the radiation pattern when there is no parasitic element. When one parasitic element 9 is added, the radiation pattern becomes narrower as shown in 32, and the divided parasitic phases 10a, 1
When 0b is added, the radiation pattern shape 33 becomes close to that without the parasitic element. On the other hand, the radiation pattern of the printed dipole antenna according to the present invention is pattern 3.
1, the shape is between 32 and 33, and electrically 1
The characteristics approach the case where the parasitic element 9 of the book is added. Therefore, if a plurality of printed dipole antennas are arranged to form a Goupole array as shown in the conventional example in FIG. A low coupling effect similar to that of a Guypole array with the addition of the parasitic element 9 can be obtained. Further, the amount of level decrease during wide-angle beam scanning can be suppressed to be smaller than when using one parasitic element 9.

In addition, although the case where the dipole and two parallel wires are formed using both sides of the dielectric plate has been described above, the present invention is not limited to this, and the dipole and two parallel wires are formed on one surface of the dielectric. All (
It can be implemented in the same way.

Moreover, although the case where the Guipole array is a linear arrangement of four elements has been described, the same effect can be obtained even when a planar arrangement or a curved arrangement is used.

〔Effect of the invention〕

As described above, according to the present invention, a metal piece is provided on the back side of the dividing gap of the divided parasitic elements, and the two divided parasitic elements are electrically connected through the capacitance formed by the thickness of the dielectric. As a result, the amount of mutual coupling can be reduced, and the amount of level drop at a wide angle can be suppressed to a small level, which is highly effective as an element antenna for a guipole array.

[Brief explanation of the drawing]

1 and 2 are structural diagrams of a printed dipole antenna according to an embodiment of the present invention, FIG. 3 is a current distribution diagram on a parasitic dipole, and FIG. 4 is a radiation pattern diagram.
Figure 5 is a structural diagram of a conventional printed dipole antenna, Figure 6 is a structural diagram of a Guipole array, Figure 7 is a configuration diagram of a Guipole array, and Figures 8 and 9 are conventional printed cardboard antennas. FIG. l...Dielectric plate, 2a, 2b...Dipole, 3a
. 3b... Parallel two wires, 5... Printed dipole antenna, 6... Phase shifter, 10a, 10b... Division parasitic element, 11... Metal piece. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] (1) In a printed dipole antenna in which two parallel wires as a feeding part and a plate-shaped dipole as a radiating part are printed on both or one side of a dielectric plate, with respect to the plate-shaped dipole described above. On one surface of the dielectric plate on the radiation side, a divided parasitic element is printed and provided parallel to the plate dipole and divided into two with a predetermined gap, and on the other side of the dielectric, A printed dipole antenna characterized in that a printed metal piece is provided on a portion corresponding to the back surface of the portion, and the gap between the divided parasitic elements is electrically connected via a capacitance.