JPH0362603A - Elevation inductive antenna - Google Patents

Abstract

PURPOSE:To select a radiation characteristic within a horizontal plane, thereby reducing the effect of a different reflecting substance from each installation site. and to improve angular accuracy by providing a multi-terminal power distribution circuit and selecting plural input terminals of the multi-terminal power distribution circuit. CONSTITUTION:An arranged radiation element 1 is connected to a multiterminal power distribution circuit 2 to select a beam direction within a horizontal plane and one terminal among 3 terminals of the circuit 2 is connected to a phase shifter 3 to scan the beam within a vertical plane depending on the beam direction. That is, radiation elements of 2-dimension arrangement in which plural radiation elements are arranged also in the horizontal direction in addition to the vertical direction and the multi-terminal power distribution circuit 2 having plural input terminals corresponding to radiation elements arranged in the horizontal direction are provided and the plural input terminals of the circuit 2 are selected. Then the horizontal plane radiation characteristic is selected to reduce the effect of a reflecting object different from each installation site to improve the angular accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an altitude guidance antenna of a microwave landing guidance system, and more particularly to switching scanning of horizontal plane radiation characteristics in an altitude guidance antenna.

[Prior Art] Conventional high-low guidance antennas of this type consist of linear arrays arranged in a line in the vertical direction in order to scan the beam in a vertical plane, and their radiating elements ensure coverage. For this purpose, printed dipole antennas with reflectors have been used.

[Problems to be Solved by the Invention] The radiation characteristics in the horizontal plane of the altitude guidance antenna of the conventional microwave landing guidance system described above are determined by the mechanical structure of the radiating element and the reflector. Therefore, in order to control the radiation characteristics in the horizontal plane, a method can be considered in which the reflector or the like is made mechanically variable, but this method has the problem of being structurally complicated.

In particular, when considering the high-low guidance antenna of a mobile microwave landing guidance system, the angle etc. of the reflector installation should be made variable for each installation site in order to avoid reflective objects that affect angular accuracy and obtain maximum effective obliteration. is extremely difficult.

[Means for Solving the Problems] The present invention has been made in view of the above problems, and makes it possible to switch the radiation characteristics in the horizontal plane to reduce the influence of reflecting objects that vary depending on the installation site. The purpose is to improve the angular accuracy, and to achieve this purpose, a two-dimensional array in which multiple radiating elements are arranged horizontally as well as vertically is used in the altitude guidance antenna of the microwave landing guidance system. A multi-terminal power distribution circuit having a radiating element and a plurality of input terminals corresponding to the radiating elements arranged in a horizontal direction is provided,
The horizontal plane radiation characteristics can be switched by selecting a plurality of input terminals of the multi-terminal power distribution circuit.

[Example] Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows the RF of a height guidance device according to an embodiment of the present invention.
It is a system diagram showing a yarn system. The number of elements arranged in the vertical direction is the same as the conventional one, but the number of elements arranged in the horizontal direction is four elements.

In FIG. 1, the array radiating element is connected to a multi-terminal power distribution circuit 2 in order to switch the beam direction in the horizontal plane, and depending on the beam direction, one of the three terminals of the multi-terminal power distribution circuit 2 is connected. is connected to a phase shifter 3 for scanning the beam in the vertical plane. Furthermore, the phase shifter 3 is connected to a vertical power divider 4 for distribution to the vertical elements.

Next, the system of the aperture 5 including the multi-terminal power distribution circuit 2 for switching the beam direction in the horizontal plane will be explained with reference to FIG.

The multi-terminal power distribution circuit 2 includes a Patler matrix composed of four 3 dB-90° hybrid couplers 6 and five delay lines 7, and an attenuator 8 that provides an aperture distribution. When each of the array radiating elements 11 to 13 is selected, the beam direction is switched and scanned by setting the power supply voltage as shown in Table 1.

Note that the phase shifter 3 and the vertical power divider 4 have the same configurations as conventional ones.

The radiating elements A to D in Table 1 are the radiating elements A shown in FIG.
- Compatible with D.

FIG. 3 schematically shows the structure of the opening 5. As shown in FIG. The opening 5 is
It is composed of a 4-layer board. The first layer is a microstrip antenna, which is a radiating element l, forming a patch antenna. The second to fourth layers are the multi-terminal power distribution circuit 2
is formed. The third layer implements the trip rate structure interlayered by the ground patterns of the second and fourth layers.

FIG. 4 shows an example of calculation of radiation characteristics in the horizontal plane.

This calculation was performed under the conditions that the horizontal array element spacing was "1/2 wavelength", the element directivity was "Co52θ", and the power supply voltage was in accordance with Table 1.

[Effects of the Invention] As explained above, the present invention provides a two-dimensional array of radiating elements in which a plurality of radiating elements are arranged in the horizontal direction as well as in the vertical direction in the elevation guidance antenna of the microwave landing guidance system. and a multi-terminal prepower distribution circuit having a plurality of input terminals corresponding to the radiating elements arranged in the horizontal direction, and configured so that horizontal plane radiation characteristics can be switched by selecting the plurality of input terminals of the multi-terminal power distribution circuit. has been done.

With this configuration, by selecting multiple input terminals of the multi-terminal power distribution circuit and switching the horizontal plane radiation characteristics, it is possible to reduce the influence of reflecting objects that vary depending on the installation site and improve angular accuracy. becomes.

[Brief explanation of drawings]

FIG. 1 shows the RF of a height guidance device according to an embodiment of the present invention.
A system diagram showing the thread system, FIG. 2 is a system diagram of the opening 5 shown in FIG. 1, and FIG. 3 is a system diagram showing the thread system.
FIG. 4 is a schematic structural diagram of the opening 5, and is a radiation characteristic diagram during horizontal plane switching scanning. 1...Array radiating element 2...Multi-terminal power distribution circuit 3...Phase shifter 4...Vertical power divider opening 3dB-90' hybrid day-lay line attenuator docoupler

Claims (1)

[Claims] In the high-low guidance antenna of the microwave landing guidance system,
A multi-terminal power distribution circuit is provided, which has a two-dimensional array of radiating elements in which a plurality of radiating elements are arranged in the horizontal direction as well as the vertical direction, and a plurality of input terminals corresponding to the radiating elements arranged in the horizontal direction. A high-low induction antenna characterized in that horizontal plane radiation characteristics can be switched by selecting a plurality of input terminals of a multi-terminal power distribution circuit.