JPH0332203A - Reflecting mirror antenna - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

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

(Prior Art) Conventionally, in this type of reflector antenna, sharing of different frequencies has been realized by configuring its feeding system as shown in FIGS. 2 and 3.

That is, the feeding system shown in FIG. 2 is a branching system having first and second input/output ends 3a and 3b for the base of a primary radiator 2, called a feeding horn, which is placed at the focal point of a reflecting mirror 1. A demultiplexer 3 is provided, and first and second input/output ends 3a, 3b of this demultiplexer 3 are provided.
Input and output of different frequencies fl and f2 are performed through the input and output terminals.

Then, the electromagnetic waves of frequencies fL and f2 which are manually inputted from these first and second input terminals 3a and 3b are guided to the primary radiator 2 via the branching filter 3, and excite the primary radiator 2. Close.

In addition, the power feeding system shown in FIG. 3 has a plurality of horn antennas 4 arranged around the primary radiator 2, and the horn antenna 4 and the primary radiator 1 feed power at different frequencies fl and f2, respectively. .

However, when the above-mentioned reflector antenna is provided with the former feeding system, its beam width is determined by the horn aperture diameter of the primary radiator 1 due to its configuration. One problem is that it is difficult to ensure an optimal beam width for each beam width.

In addition, in the case where the latter feeding system is provided, the horn antenna 4 is usually determined by determining the shape and size of the feeding system in accordance with the shape and size of the reflecting mirror 1 and the desired beam width.
Since the aperture diameter is limited by the upper limit of the aperture diameter, it is extremely troublesome to design and manufacture a feed system to ensure an optimal beam width depending on the frequency. This is especially true when mounted on a space vehicle such as an artificial satellite, which poses a major problem in the design and production of the power supply system, since the shape and dimensions of the reflector are restricted.

(Problems to be Solved by the Invention) As described above, with conventional reflector antennas, if the frequencies to be trained differ greatly, it may be difficult to secure the optimum beam width for each frequency. Alternatively, if there are restrictions on the shape and dimensions, it becomes difficult to secure an optimal beam width, and both have the problem of being troublesome to design and manufacture.

This invention was made in view of the above circumstances, and aims to provide a reflector antenna that is simple, can secure an optimal beam width, and can be made smaller. .

[Structure of the Invention] (Means for Solving the Problems) The present invention includes a first power feeding system having a primary radiator disposed at the focal point of a ring 1 (mirror and feeding power at a first frequency); a second feeding system having a plurality of array elements in which a plurality of parasitic elements are stacked at a predetermined interval on a patch antenna arranged at a predetermined interval around the primary radiator; A reflector antenna is constructed by comprising:

(Function) According to the above configuration, the first and second power supply systems first
The feeding system of the second feeding system is set to correspond to the first frequency, the arrangement interval of the array elements of the second feeding system is set correspondingly, and the number and shape and size of the parasitic elements of the array element are then set. By setting the distance between the first and second frequencies so as to correspond to the second frequency, optimum beam widths corresponding to the first and second frequencies are ensured. Therefore, by appropriately setting the parasitic elements of the second power supply system, the second power supply system can be
Since it is possible to set the optimum beam width corresponding to the frequency of
It becomes possible to aim at miniaturization.

(Example) Hereinafter, an example 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, in which a primary radiator 11 constituting a first feed system is connected to a focal point of a reflector 10, for example, to a communication device (not shown). It is arranged via a waveguide 12. This primary radiator 11 is set corresponding to a desired frequency fl, and around it, for example, □
, first to fourth patch antennas 13a to 13d are arranged. First to fourth patch antennas 13'a~~1
3d is connected to the main power divider 16 which is connected to the communication equipment (not shown) through the first and second power dividers 14 and 15, and has an abbreviation made of, for example, a metal material on its upper surface. A plurality of disk-shaped parasitic elements 17 are stacked and attached at predetermined intervals in substantially the same manner via pillars 18 . The number, shape, and mutual spacing of the parasitic elements 17 are set in accordance with the desired beam width at the frequency f2.

In the above configuration, when transmitting and receiving at frequency 11, power is supplied to the primary radiator 1 to perform transmission and reception.

When transmitting and receiving the frequency f2, the array element composed of the first to fourth patch antennas 13a to 13d and the parasitic element]7 is supplied with power, and for example, when transmitting, the main power divider 16 distributes the electromagnetic waves. After that, the array elements are excited via the first and second power dividers 1415, respectively.

In this way, the reflector antenna has a first radiator around the primary radiator 11 constituting the first feeding system corresponding to the frequency fl.
A second power feeding system corresponding to the frequency fl in which a plurality of array elements in which a plurality of parasitic elements 17 are stacked at predetermined intervals on fourth batch antennas 3a to 13d are arranged at predetermined intervals. It was configured to provide . According to this, the primary radiator 11 is first set to correspond to the frequency fl, and the first to fourth patch antennas 1.
3 Set the arrangement spacing of parasitic elements 17 a to 13d, and then adjust the number, shape, and spacing of the parasitic elements 17 according to the frequency f.
By setting it to correspond to l, it is possible to secure an optimal beam width corresponding to frequencies fl and f2. Therefore, when creating the second feeding system, set the parasitic element appropriately. As a result, the design and manufacture can be made as simple as possible. Also, according to this, by configuring the second feeding system using a batch antenna, the size can be reduced as much as possible compared to the conventional configuration using a horn antenna. Therefore, it is expected to have an effective effect especially when installed on a space vehicle such as an artificial satellite.

Note that in the above embodiment, a case has been described in which four array elements constituting the second feed system are arranged around the primary radiator 11, but the present invention is not limited to this number and can be applied. be.

Therefore, it goes without saying that the present invention is not limited to the above embodiments, and that various modifications can be made without departing from the spirit of the invention.

[Effect of the invention] As detailed above, according to the present invention, it is possible to simplify the
It is possible to provide a reflector antenna that can ensure an optimal beam width and can be made smaller.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the main parts of a reflector antenna according to an embodiment of the present invention, and FIGS. 2 and 3 are diagrams showing the main parts of a conventional reflector antenna. 10... Reflector, 11... Primary radiator, 12...
Waveguide, 13a to 13d... First to fourth patch antenna, 1415... First and second power divider, 1
6... Main power divider, 17... Parasitic element, 1
8... Prop. 3rd Figure 15-

Claims (1)

[Claims] a first feed system having a primary radiator placed at the focal point of the reflector and feeding at a first frequency; and a plurality of patch antennas placed around the primary radiator at predetermined intervals. A reflector antenna comprising: a second feeding system having a plurality of array elements in which parasitic elements are stacked at predetermined intervals.