JP2740007B2 - Reflector antenna - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a reflector antenna mounted on, for example, an artificial satellite and used for transmitting and receiving radio waves of different frequencies.

(Prior Art) Conventionally, in a reflector antenna of this type, the feed system is configured as shown in FIGS. 2 and 3, thereby realizing common use at different frequencies.

That is, the feed system shown in FIG. 2 is a splitter having first and second input / output terminals 3a and 3b with respect to a base of a primary radiator 2 called a feed horn disposed at the focal point of the reflecting mirror 1. A duplexer 3 is provided to input and output different frequencies f1 and f2 via first and second input / output terminals 3a and 3b of the duplexer 3. And
The frequency f input from these first and second input terminals 3a, 3b
The electromagnetic waves 1 and f2 are guided to the primary radiator 2 via the duplexer 3 to excite the primary radiator 2.

In the feed system of FIG. 3, a plurality of horn antennas 4 are arranged around the primary radiator 2, and the horn antenna 4 and the primary radiator 2 have different frequencies f1 and f1, respectively.
Power supply of f2 is performed.

However, in the reflector antenna, when the former feed system is provided, the beam width is determined by the horn aperture diameter of the primary radiator 2 due to its configuration. There has been a problem that it is difficult to secure an optimum beam width for each time.

In addition, when the latter power supply system is provided, usually,
Since the shape and size of the feed system are determined in accordance with the shape and size of the reflector 1 and the desired beam width, the upper limit of the aperture diameter of the horn antenna 4 is restricted. There was a problem that the design and production of the power supply system for securing the power supply were very troublesome. In particular, when it is mounted on a space vehicle such as an artificial satellite, the design and production of the power supply system become a serious problem because the shape and size of the reflector are restricted.

(Problems to be Solved by the Invention) As described above, in the conventional reflector antenna, if the shared frequencies are significantly different, it is difficult to secure an optimum beam width for each frequency, Alternatively, if the shape and dimensions are restricted, it is difficult to secure an optimum beam width, and all of them have a problem that designing and manufacturing are troublesome.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a reflector antenna which can realize an optimum beam width easily and can be made smaller. .

[Means for Solving the Problems] According to the present invention, a primary radiator for feeding power at a first frequency is arranged opposite to a focal point of a reflecting mirror, and the first radiator is arranged via the reflecting mirror. A first power supply system for transmitting and receiving a signal of a frequency, and a plurality of array elements in which a plurality of parasitic elements are stacked on a patch antenna for feeding at a second frequency on a mirror surface of the reflecting mirror at a predetermined interval. And a second feeding system for transmitting and receiving the signal of the second frequency via the plurality of array elements to constitute a reflector antenna.

(Operation) According to the above configuration, the first and second power supply systems first set the first power supply system to correspond to the first frequency, and accordingly, the second power supply system By setting the arrangement intervals of the array elements, and then setting the number, shape and size of the parasitic elements of the array elements and the interval between them to correspond to the second frequency, The corresponding optimum beam width is secured. Therefore, by appropriately setting the parasitic element of the second power supply system, it is possible to set the second power supply system to an optimum beam width corresponding to the second frequency, so that a simple design and manufacture is possible. Is realized, and the size can be reduced.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a reflector antenna according to an embodiment of the present invention. At a focal point of a reflector 10, a primary radiator 11 constituting a first feed system is connected to, for example, a communication device (not shown). It is arranged via a waveguide 12. The primary radiator 11 is set corresponding to a desired frequency f1, and a surrounding mirror is provided.
On the mirror surface of 10, for example, first to fourth patch antennas 13a to 13d constituting an array element of a second feeding system are arranged. The first to fourth patch antennas 13a to 13d are connected to a main power distributor 16 connected to the communication device (not shown) via first and second power distributors 14 and 15, and On the upper surface, a plurality of substantially disk-shaped parasitic elements 17 made of, for example, a metal material are stacked and attached at predetermined intervals substantially in the same manner via a support column 18. The number, shape and size of the parasitic elements 17 are set in accordance with the desired beam width at the frequency f2.

In the above configuration, the primary radiator 11 is supplied with power when transmitting and receiving at the frequency f1. And the frequency f2
When transmitting / receiving the first to fourth patch antennas 13a to 13a-1
An array element composed of the 3d and the parasitic element 17 is supplied with power. For example, at the time of transmission, after the electromagnetic wave is distributed by the main power distributor 16, the array is transmitted through the first and second power distributors 14, 15. The elements are each excited.

As described above, the reflector antenna has a plurality of parasitic elements on the first to fourth patch antennas 13a to 13d around the primary radiator 11 constituting the first feed system corresponding to the frequency f1.
The second power supply system corresponding to the frequency f2 in which a plurality of array elements 17 are stacked at predetermined intervals is arranged at predetermined intervals. According to this, first the primary radiator
11 is set so as to correspond to the frequency f1, the arrangement intervals of the first to fourth patch antennas 13a to 13d are set accordingly, and then the number, shape, size and mutual By setting the interval between them so as to correspond to the frequency f2, the optimum beam width corresponding to the frequencies f1 and f2 can be ensured. Since the device can be manufactured by appropriately setting the elements, design and manufacture as simple as possible are realized. In addition, according to this, since the second power supply system is configured using a patch antenna, compared with a conventional configuration using a horn antenna,
Since the size can be reduced as much as possible, an effective effect can be expected particularly when it is mounted on a spacecraft such as an artificial satellite.

In the above embodiment, the case where four array elements constituting the second power supply system are arranged around the primary radiator 11 has been described. However, the present invention is not limited to this number but can be applied. is there.

Therefore, it is needless to say that the present invention is not limited to the above-described embodiment, and that various modifications can be made without departing from the scope of the present invention.

[Effects of the Invention] As described above in detail, according to the present invention, it is possible to provide a reflector antenna that can easily secure an optimum beam width and can be downsized. Can be.

[Brief description of the drawings]

FIG. 1 is a view showing a main part of a reflector antenna according to an embodiment of the present invention, and FIGS. 2 and 3 are views showing a main part of a conventional reflector antenna. 10 ... Reflector, 11 ... Primary radiator, 12 ... Waveguide, 13a
... 13d... First to fourth patch antennas, 14, 15... First and second power dividers, 16.
…… parasitic element, 18 …… post.

Claims (1)

(57) [Claims] A first radiator for feeding power at a first frequency at a focal point of a reflecting mirror, and a first feeding system for transmitting and receiving a signal of the first frequency via the reflecting mirror; On the mirror surface of the reflector, a plurality of array elements in which a plurality of parasitic elements are stacked on a patch antenna that feeds at a second frequency are arranged at predetermined intervals, and the plurality of array elements are arranged via the plurality of array elements. And a second power supply system for transmitting and receiving a signal of a second frequency.