JPH0414521B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a direction-finding antenna device constructed by integrally assembling direction-finding antennas that use different frequency bands.

[Conventional technology]

There are many types of direction finding antennas that are commonly used, such as loop antennas and adobe antennas, and each antenna is selected and used depending on its electrical characteristics, structure, and price.
Normally, due to electrical characteristics, loop antennas are used for long and medium wave bands, and whip antennas or dipole antennas are used for short waves and very high frequency bands, but for moving objects including ships, due to structure and dimensions. Loop antennas are often used for shortwave bands. However, in modern mobile bodies including ships, it has become necessary to detect directions from the long to medium wave band to the very high frequency band. . In such a case, two types of antennas are required: one for low frequency bands and one for high frequency bands. In particular, since the measurement accuracy of a direction finding antenna is determined by its directivity, in many cases a high mast is installed on top of the antenna to avoid the influence of the moving object itself. Therefore, increasing the number of antennas means
Since a location with good conditions is required, it is preferable to achieve the purpose with one antenna as much as possible.

[Problem to be solved by the invention]

It is conceivable to provide a structure in which the direction-finding antenna using a loop antenna as described above and the direction-finding antenna with different usage frequencies are assembled together, but it is possible to provide an antenna that is electrically and mechanically satisfactory. The problem is how to configure it to do so.

[Means to solve the problem]

The present invention provides a direction finding antenna in which a plurality of loop antennas as described above intersect at equal angular intervals on a plane and are held by providing a base at the lower intersection, that is, a first antenna; In a direction finding antenna consisting of a plurality of antennas used for direction finding in a frequency band different from that of a loop antenna, that is, a direction finding antenna configured integrally with a second antenna, each of the above equal angular intervals is divided into two. While arranging the dipoles in the angular direction, the projecting arm of each dipole is held by a base provided at the center to form the second
The above problem can be solved by providing a second antenna configuration means that configures an antenna, and a base integral configuration unit that integrally configures the base of the first antenna and the base of the second antenna. This is how it was done.

〔Example〕

Examples will be described below with reference to figures.

FIG. 1 shows a perspective view of an embodiment of the present invention, in which a base 4 of an antenna 3 formed by a four-element dipole is placed on a base 2 of a loop antenna 1 arranged orthogonally.
This is a direction-finding antenna device with an integrated structure, and as shown in the figure, the lower part can be fixed at an arbitrary height with a support 5. The planar arrangement is such that each element of the four-element dipole antenna, that is, each dipole, is located in the middle of each loop antenna 1, as shown in FIG.

To explain this configuration in detail, the loop antennas of the antenna 1 for direction finding using loop antennas are arranged intersectingly at equal angular intervals as shown in Figure 2 on a plane. At the same time, as shown in FIG. 1, a base 2 is provided at the lower intersection of the loop antenna 1 to hold it.

In addition, each dipole of the antenna 3 for direction finding using a four-element dipole is arranged in a second position on a plane.
As shown in the figure, the loop antennas 1 are arranged in the angular direction that bisects the above-mentioned equal angular intervals, and the horizontal support arms supporting each dipole, that is, the overhang arms, are provided at the center. It is held by the base 4.

The base 2 and the base 4 are integrated.

[Modification example]

The present invention can be modified and implemented as follows.

As shown in FIG. 3, the antenna 1 for direction finding using a loop antenna and the antenna 3 for direction finding using a four-element dipole are arranged in the same way as shown in FIG. 2 on a plane. At the intermediate position of the support 6 provided between the base 2 of the and the part where each loop antenna intersects above,
The base portion 4 of the antenna 3 described above is arranged and provided.

Further, the support column 6 is made of a material that does not affect the electrical characteristics of the loop antenna, such as an insulator.

The antenna 1 is made into a plurality of loop antennas, and the antenna 3 is made into a plurality of dipoles, and the dipoles are arranged at positions that maintain balance with respect to the loop antennas, as in the above embodiment.

〔Effect of the invention〕

In general, a direction finding antenna produces an error in direction measurement due to the presence of a nearby disturbing object, but it is a well-known fact that the degree of the error largely depends on the resonance condition of the disturbing object. In the case of the combination of antennas according to the present invention, since the frequency bands used are different, their mutual influence is relatively small. Furthermore, even if an error occurs, since the antennas are arranged so as to maintain a balance between them as shown in FIG. 2, the error caused by mutual influence will appear as an n-fold quadrant error. In this way, it is easy to correct the error that appears as a sine wave of an integral multiple, so it can be made almost non-problematic.

Furthermore, according to the present invention, in FIG.
The base 2 and the base 4 are integrated, and in the case of the one in FIG. 3, the base 4 is held by the support 6, so it has mechanical vibration resistance and has a single volume as a direction finding antenna. Since it can be formed to the same size, it can be installed in a high place where there are few nearby disturbing objects, and as a result, it has the advantage of being able to perform direction detection with less error.

[Brief explanation of drawings]

The drawings show an embodiment, and FIGS. 1 and 3 are perspective views, and FIG. 2 is a plan view. DESCRIPTION OF SYMBOLS 1... A direction finding antenna using a loop antenna, 2... Base, 3... A direction finding antenna using a dipole, 4... Base, 5... Support, 6... Support.

Claims (1)

[Scope of Claims] 1. A direction finding antenna (hereinafter referred to as a first antenna) in which a plurality of loop antennas are arranged in a plane and intersect at equal angular intervals, and a base is provided and held at the lower intersection portion; A direction-finding antenna (hereinafter referred to as a second
(referred to as an antenna); a) dipoles are arranged in each angular direction that bisects the above-mentioned equal angular intervals; a second antenna configuring means for holding and configuring the second antenna; and b) base integral configuring means for integrally configuring the base of the first antenna and the base of the second antenna. Antenna device for direction finding. 2. A direction finding antenna (hereinafter referred to as the "first antenna") in which a plurality of loop antennas are arranged in a plane and intersect at equal angular intervals and are held by providing a base at the lower intersection, and a use different from the above-mentioned loop antenna. A direction finding antenna (hereinafter referred to as a second direction finding antenna) consisting of multiple antennas used for direction finding in frequency bands.
(referred to as an antenna); a) dipoles are arranged in each angular direction that bisects the above-mentioned equal angular intervals; a second antenna constituting means that holds the base of the second antenna to configure the second antenna; b a support that is provided between the base of the first antenna and an upper intersection of the first antenna 1. A direction finding antenna device, comprising: base support strut means disposed at an intermediate position for support.