JPH046906A - Fan beam antenna in common use for two frequency bands - 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 [Industrial Field of Application] The present invention relates to a dual frequency band shared fan beam antenna used in a quasi-microwave band.

[Prior Art] FIG. 4 is a diagram showing a conventional fan beam antenna.
In the figure, ) is a die-ball antenna, and (2) is a reflector.

Next, the operation will be explained. Die ball antenna (1)
As shown in Figure 5, the radiation pattern of one element is uniform within the magnetic interface perpendicular to the die-ball antenna, and is figure-eight-shaped within the electric interface including the die-ball antenna, resulting in a so-called donut-shaped directivity. Become.

By arranging multiple elements of this die ball antenna in the vertical direction and installing a reflector (2) as shown in Fig. 4, the amplitude of each antenna is 1 due to the array effect of the die ball antennas in the vertical plane. By appropriately selecting the phase, the beam width can be narrowed to increase the gain, and the beam direction can be tilted from the direction perpendicular to the die ball antenna. In addition, in the horizontal plane, there are 9 reflectors (2
), the implementation is not uniform, resulting in a fan beam antenna with maximum radiation level in one direction. The beam width of the fan beam in the horizontal plane can be changed by changing the opening angle O of the reflector.

[Problems to be Solved by the Invention] Since the conventional fan-shaped beam antenna is configured as described above, when used in two frequency bands, a reflector and antenna connected to the two frequency bands are required. The same beam width cannot be obtained in the two frequency bands because the electrical dimensions of the positions are different. Furthermore, it is difficult to design a feeder circuit with a die-ball antenna over a wide band. There were problems such as:

This invention was made in order to solve the problems described in "-", and by making the beam widths equal in two frequency bands and separating the feed circuits in each frequency band, the feed circuit The purpose of this invention is to obtain a fan-shaped beam antenna that can be used for two frequency bands and which can be easily designed.

[Means for solving the problem] The fan beam antenna for dual frequency bands according to the present invention is as follows:
The radiating element for one frequency band is a die-ball antenna with one reflector, and the radiating elements for other frequency bands are microstrip array antennas provided on the reflector.

[Operation] In this invention, by changing the type of radiating element and separating the two frequency bands, it is possible to design the beam width independently for each, and the feeding circuit can also be separated and designed independently. .

[Example] An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1, (1) is a die ball antenna.

(2) is a reflector, (3) is a microstrip antenna, and (4) is a dielectric plate.

The operation of the die ball antenna (1) and the reflector (2) is similar to that of a conventional antenna. 2) Distance 1 Length of reflector! 11 Determine the reflector opening angle θ. The other frequency f2 radiating element is
The above reflector plate (2) for frequency f1 is used as a base plate, and microstrip antennas (3) are arranged and formed on a dielectric plate (4) mounted thereon. The beam width in the horizontal plane at frequency f2 can be changed by controlling the amplitude and phase of the power feeding to the plurality of microstop antennas (3) arranged in the horizontal plane. It is also possible to match.

Further, in the above embodiment, the dielectric plate (4) is placed on the reflection plate (2).
) and microstrip antenna (3), but if the characteristics as a reflector at frequency f1 are greatly affected by the dielectric plate (4) and microstrip antenna (3), the As shown in Figure 2, by forming a frequency selection plate (5) on the entire upper surface of the microstrip antenna (3), which reflects radio waves at frequency f1 and transmits them at frequency f2, the surface of the two-frequency selection plate (5) acts as a reflector and can reduce the influence of the dielectric plate (4) and microstrip antenna (3).

In addition, as shown in Fig. 3, in order to widen the band of the microstrip antenna (3), when using a microstrip antenna (3) with an A-sized parasitic element (6), the parasitic element (6) A similar effect can be obtained by providing a frequency selection plate (5) above.

[Effects of the Invention] As described above, according to the present invention, a dual frequency band common fan beam antenna is constructed by combining a die ball antenna with a reflector and a microstrip antenna array, so that beams can be transmitted independently in each of the two frequency bands. This has the effect that the width can be designed and the power supply circuit can be designed easily.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a dual frequency band common fan beam antenna according to one embodiment of the present invention, FIGS. 2 and 3 are diagrams showing other embodiments, and FIG. 4 is a diagram showing a conventional fan beam antenna. , FIG. 5 is a diagram showing the beam shape of the die ball antenna. (1) is a die ball antenna, (2) is a reflector,
(3) is a microstrip antenna, (4) is a dielectric plate, (5) is a frequency selection plate, (6) is a parasitic element, (7)
) is a directional pattern. In addition, in FIG. 9, the same reference numerals indicate the same or equivalent parts.

Claims (2)

[Claims] (1) In a fan beam antenna used in two frequency bands, the radiating element for one frequency band is a die-ball antenna with a reflector, and the radiating element for the other frequency band is a microstrip array antenna provided on the reflector. A fan-shaped beam antenna that can be used for two frequency bands. (2) In a fan beam antenna used in two frequency bands, the radiating element for one frequency band is a die-ball antenna with a reflector, and the radiating element for the other frequency band is a microstrip array antenna provided on the reflector. , and the microstrip antenna is provided on a frequency selection plate that reflects at the frequency used by the die ball antenna and transmits at the frequency used by the microstrip antenna.