JPH01254007A - Stationary antenna for radar - Google Patents

Abstract

PURPOSE:To provide 360 deg. scanning to the radar by arranging plural element antennas perpendicularly in radial direction at an equal interval on a circumference, providing a printed board provided in parallel with a print power supply circuit and a switching circuit to the element antenna in the circumferential face and covering the board by a radio wave absorbing body from both the sides. CONSTITUTION:The plural element antennas 4 each made of a printed circuit board 2 are arranged perpendicularly in radial direction at an equal interval nearly on a circumference, number of the circuits each being a feeding circuit 5 and a switching circuit 6 provided on the printed circuit board 2 provided in a face forming circumference as the feeding means to the element antenna 4 is provided by the number of the element antennas 4. Then both the sides of the printed circuit board 2 is covered by a radio wave absorbing body 3 and a radio wave reaching the element antenna 4 from the feeder circuit 5 is interrupted. With the switching circuit 6 turned on/off in time series in the adjacent order, the directivity pattern of the element antenna 4 itself is turned by 360 deg.. Thus, this is equivalent to the turning of one element antenna by 360 deg., then the 360 deg. search is given to the radar.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to an antenna for a direction measurement or detection device using radio waves.

[Summary of the invention]

In order to obtain a simple radar antenna, a plurality of element antennas are arranged approximately on the circumference at equal intervals and perpendicular to the radial direction, and each element antenna is arranged in a plane formed by the circumference. A printed circuit board with a printed power supply circuit and a switching circuit arranged in parallel is installed.
A fixed antenna for radar that covers the board with radio wave absorbers from the front and back.

[Conventional technology]

° As the antenna for conventional high-grade radar equipment, the fifth
As shown in the figure, a rotating parabolic antenna using an electromagnetic horn or a dipole (not shown) as a -order radiator, and a planar array antenna whose arrangement is shown in FIG. 6 are known. A rotating parabolic antenna scans a beam by mechanically rotating it. In a planar array antenna, the direction of the beam can be set to a desired position by supplying a feeding current to each element antenna with appropriate consideration of phase and amplitude. Of course, the beam can also be swung periodically. In addition to these antennas, there are also known antennas that use diode switching to set the direction of the beam to a desired location (see, for example, Japanese Patent Laid-Open No. 55-96703).

[Problem to be solved by the invention]

In recent years, consumer transmitter/receiver devices have become increasingly popular due to the combination of advances in communication technology and social demands. It has become commonplace for vehicles to be equipped with communication devices to communicate with each other.

However, a simple radar antenna device that can confirm the direction of the other party's communication and concentrate radio waves in that direction is not yet known. An object of the present invention is to provide a simple fixed radar antenna for a mobile communication device within several hundred meters to confirm the direction of the other party and communicate with the other party.

[Means to solve the problem]

In order to achieve the above object, a plurality of element antennas made of printed circuit boards are arranged approximately on a circumference in a radial direction perpendicularly and at regular intervals, and the circumference is configured as a means for feeding power to the element antennas. The number of feeder circuits and switching circuits connected in series on a printed circuit board provided within the plane is arranged in parallel in the same number as the element antennas, and both sides of the printed circuit board are covered with a radio wave absorber, and the power reaches the element antennas from the feeder circuit side. Block radio waves.

[Effect]

All the input side terminals of the switching circuit of the radar fixed antenna configured as described above are connected in common and a signal is supplied. Then, by turning on and off each of the switching circuits in adjacent order in time series, the directivity pattern of a single element antenna rotates 360 degrees. Isometrically, one element antenna rotates 360 degrees, so the radar's 36
It will have a 0 degree search function.

〔Example〕

An embodiment of the radar fixed antenna of the present invention will be described with reference to the drawings. In FIG. Mount vertically. Printed circuit board 2
is covered with radio wave absorbers 3 from above and below, and radio waves arriving at the element antenna from the feeding circuit side are blocked. FIG. 2 is a perspective view of essential parts of this embodiment. The radio wave absorber 3 is excluded. In the figure, the element antenna 4 is constructed of metal foil on the surface of the element antenna substrate 1, and the printed circuit board 2 is fabricated and used with metal foil stretched on both sides. Two output leads made of metal foil of the element antenna 4 are pulled out to the back side of the element antenna board 1 by through-hole plating, and connected to one end of the printed power supply circuit 5 configured on the printed board 2 and the conductor 8 of the printed board 2. connected to. The other end of the printed power supply circuit 5 is led and connected to a switching circuit 6. In this embodiment, the switching circuit 6 is constructed by connecting a capacitor and a diode, and an inductor 7 having a predetermined inductance is connected to a connection point between the capacitor and the diode. The output side of the switching circuit 6 is connected to a printed feed circuit 9 provided on the printed circuit board 2, and furthermore, the printed feed circuits 9 from the individual element antennas 4 are all connected together to form one output (or input) line. become. The inductor 7.10 serves to prevent signals traveling through the printed feed circuit 5.9 from being shunted to the switching control circuit (not shown).

FIG. 3 shows a circuit diagram of the radar fixed antenna of this embodiment. In the figure, the inductor L! By applying a predetermined positive voltage output from a switching control circuit (not shown) to the anode of the switching diode D, the switching diode D is turned on, and the antenna A1 is turned on.
The received signal from is obtained as output. At this time, other switching diodes are turned off.

In this radar fixed antenna, the element antennas 4 are arranged approximately on the circumference, and the radio wave absorber 3 is installed inside the circle formed by the element antenna group, so the directivity pattern is as shown in Fig. 4. It becomes like Pl. That is, there is no sensitivity to radio waves from the radio wave absorber side in the figure-eight directivity characteristic in free space. Next, in FIG. 3, when the voltage applied to the switching diode D1 is made zero and a predetermined positive voltage is applied to the switching diode D2 to turn it on, the directivity pattern becomes as shown at P2 in FIG. 4. By sequentially switching on the switching diodes and turning them on, the directivity of this radar fixed antenna is rotated by 360 degrees.

When this radar fixed antenna, transceiver, and azimuth distance measurement calculation device are combined into one device (not shown), and equipped with a transceiver device (not shown) that sends out the rear response signal received by the other party. By repeating signal transmission and reception and switching antenna directivity, the direction and distance of the other party can be determined.

[Effects of the Invention] Since the present invention is configured as described above, it produces the effects described below.

A simple fixed antenna for radar that can electrically scan 360 degrees in the circumferential direction can be obtained by the configuration of a group of element antennas arranged approximately on the circumference, a switching circuit attached to each element antenna, and a radio wave absorber. Ta. A simple radar device can be obtained by combining the antenna of the present invention with a transceiver equipped with an azimuth/distance measurement calculation device. It is also possible to use the simple radar device as a navigation device by mounting it on a car. or,
Individuals with small portable transceivers can be located.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway perspective view of a fixed antenna for radar;
The figure is a perspective view of the main part, FIG. 3 is a circuit diagram, and FIG. 4 is a directivity pattern diagram. FIG. 5 shows a conventional rotating parabolic antenna for radar, and FIG. 6 shows an example of the arrangement of a conventional planar array antenna. 1-・---111--Element antenna board 2-・-・
--- Printed circuit board 3 --- Radio wave absorber 4 --- Element antenna 5 --- Printed power supply circuit 6 --- Switching circuit 7---------Inductor 8-----One conductor 9----Printed power supply circuit 10----
--- Inductor it --- Insulator 12 - --- Signal line hole -- Figure 1 A5 0 Route diagram Figure 4 Radar rotary knob baller antenna life 5 Braca array antenna arrangement η11 Figure 6

Claims (1)

[Claims] It has a plurality of element antenna boards each having an element antenna formed on a printed circuit board, it has a printed power feeding circuit and a switching circuit for feeding power to the element antenna, it has a radio wave absorber, and the element antenna board is abbreviated as A printed power feeding circuit and a switching circuit for feeding power to the element antenna are arranged on a circumference at equal intervals and perpendicular to the radial direction of the circumference, and are arranged in series in a plane formed by the circumference. A fixed antenna for radar, comprising a board on which a plurality of circuits are arranged in parallel, and the board is covered with radio wave absorbers from the front and back sides, and radio waves from the feeding circuit side to the element antenna are blocked.