JPS5820006A - Antenna device - Google Patents

Abstract

PURPOSE:To eliminate the effect of an undesired wave in a short time, by composing a zero pattern of a radiation pattern in the arriving direction of a desired wave and then composing a zero point of the radiation pattern to an angle in the arriving direction of the undesired wave which is detected by another angle. CONSTITUTION:A detecting circuit 8 detects first the interference of an undesired wave in case when the arriving direction is known for a desired wave. If the interference is detected, a judging circuit 10 applies a judging signal to an angle indicating circuit 10 to detect the arriving direction of the undesired wave. The circuit 10 indicates the arriving direction thetaS of the desired wave and an optional angle thetaN other than thetaS to the next arithmetic circuit 12. The circuit 12 forms a zero point in the direction thetaS based on the above-mentioned judging signal and an angle indication and then calculates an oscillating distribution to form a zero point also to the angle thetaN. The circuit 10 replaces successively the angle thetaN and detects the angle thetaN in the arriving direction of the undesired wave where the electric power received at a signal receiver 7. For a radiation pattern obtained under such conditions, a main beam is turned toward the desired wave and a zero point is composed in the arriving direction of the undesired wave. As a result, the effect of the undesired wave can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION Jin's invention relates to a front antenna device that is susceptible to unnecessary radio waves in communications, broadcasting, radar, and the like.

The conventional adaptive array antenna that automatically removes unnecessary radio wave tubes optimizes the signal-to-noise ratio by adjusting the excitation amplitude and excitation phase of each element antenna, correlating the signal component and noise component (fk), and optimizing the signal-to-noise ratio. Adjustments are made to synthesize the zero point of the radiation pattern in the direction of arrival of unwanted waves. In such a method, when the number of element antennas is large, it takes a long time to converge to provide an optimal excitation distribution, and the configuration of one circuit is complicated, so it is difficult to realize it from the viewpoint of reliability during 11-hour processing.

In order to eliminate these drawbacks, this invention first synthesizes the zero points of the radiation pattern in that direction under the condition that the direction of arrival of the desired wave is known, and then scans the zero points of the radiation pattern at another angle. In particular, it is characterized by detecting the arrival direction of the cine essential wave and synthesizing the zero points of its angular fK radiation pattern, and its purpose is to remove unnecessary waves in a short time using a simple table construction. A detailed explanation will be given below with reference to the drawings.

FIG. 1 shows the operating procedure of this invention.

FIG. 1(a) is a diagram showing a radiation pattern before the direction of arrival of Fi unnecessary waves is known], in which unnecessary waves arriving from an angle θ1 are received as side lobes. Figure 1 (In order to detect the arrival direction of unwanted waves, the zero point of the radiation pattern θBK is formed in the direction of arrival of the desired wave, and only unnecessary waves are received, and another angle gK zero point is formed. This is the radiation pattern at .The zero point of the radiation pattern is kept in the arrival direction of the desired wave, and the zero point of the radiation pattern is scanned at a different angle.
The angle f at which the received power is minimum is the arrival direction of the unnecessary wave 0
According to the above procedure, if the arrival direction θN of the unnecessary waves is detected, the zero point of the angle f IN K radiation pattern is established as shown in Figure 1 (C), and the main beam is placed in the arrival direction 08 of the rare waves. Adjust the excitation amplitude and excitation phase to obtain a radiation pattern with .

Next, we will explain how to obtain the excitation distribution to obtain the radiation pattern having the desired angle [K zero point] as shown in Figure 1.
Show the diagram by hanging it. Figure 2 ←) shows the initial state.
Let the angle f ax IIC zero be synthesized. Figure 2(b)' is a radiation pattern with main beam at angle θNK,
This reception level a1 is taken to be equal to the side rope level a1 at the angle θMeIC of the radiation pattern in FIG. 2(a). If this radiation pattern in Fig. 2) is superimposed with the radiation pattern in Fig. 2 (1) in opposite phase, a radiation pattern with a zero point at the angle f01 can be obtained as shown in the radiation pattern in Fig. 2(e). Figure 3 shows an embodiment of the present invention, in which rII is an array antenna constructed by arranging a plurality of element antennas (2), and 蜀 is a plurality of amplitude variable devices (4I).

An excitation distribution adjuster consisting of a phase shifter (5), C6) is a sum circuit, an ff1ij receiver, and (8I is an unnecessary wave detection circuit).

(9) is a judgment circuit that generates a judgment signal to determine whether the direction of arrival of unnecessary waves should be detected (unwanted wave arrival direction detection mode) or whether a zero point should be combined with the direction of arrival of unnecessary waves (unwanted wave removal mode); aS is the main circuit; This is an angle indicating circuit that indicates the direction angle to direct the beam and the direction angle to synthesize the zero points. It was. An unnecessary wave arrival direction detecting device am is constituted by the receiver (η), the unnecessary wave detection circuit (81), the judgment circuit (1), and the angle indicating circuit a-.

aS is an excitation distribution calculation circuit □, αl is a control circuit, and a- is a drive circuit.

The original operating procedure under the condition that the rare wave arrival direction is known is that the detection circuit (III) first detects whether or not unnecessary waves are interfering, and if there is interference, K1-4. The circuit provides a judgment signal for detecting the arrival direction of unwanted waves to the angle indication circuit section.The angle indication circuit... selects any angle f0M other than the desired wave arrival direction θs1!-08 to the next excitation distribution calculation circuit. Instruct Q!IK.Based on the judgment signal and angle instruction, the arithmetic circuit O calculates the excitation distribution to form a zero point in the direction of arrival of the desired wave 08, and also form a zero table at the angle θNK. Based on the result of the calculation, the control circuit controls the drive circuit αΦ to control the amplitude variable device (4I,
Phase shifter body) K is required! ! gives a distribution.

In this state, the angle indicating circuit updates the hitting angle f-axis one after another, and selects the angle ON1 at which the received power at the receiver ff) is the minimum.
Detect. This angle is the unwanted wave arrival direction. If the arrival direction elN of unnecessary waves is detected, 1 judgment circuit (9)
is the direction of arrival of the desired wave, θB, based on the judgment signal that directs the main beam in the direction of arrival of the desired wave and the zero point in the direction of arrival of the unwanted wave. The direction θN1 is instructed to the next stage circuit. Based on this instruction and the above judgment signal, the excitation distribution calculation circuit (
In 2), the required excitation distribution is calculated.

Based on this calculation result, the control circuit oh drive circuit a- is controlled to give the amplitude variable device (4I, phase shifter 151) the necessary amplitude distribution. In this state, the radiation pattern of the antenna is such that the main beam is directed in the direction of the desired wave. is directed.

This is because zero points are synthesized in the direction of arrival of the unnecessary waves.

The detection circuit (8) does not detect unnecessary waves and obtains a signal from which the influence of unnecessary waves has been removed. If the unwanted wave arrival direction deviates from θN and unnecessary wave interference is detected, the mode is immediately switched to the unwanted wave arrival direction detection mode, and the above operation is repeated to remove the influence of the unnecessary waves.

As described above, according to the present invention, the influence of unnecessary waves can be eliminated in a short time using a simple structure mainly consisting of main beam operation and switching.

Although the case where the direction of arrival of unnecessary waves is one is described above, the present invention is not limited to this, and even when there are a plurality of directions of arrival of unnecessary waves, a zero point can be formed in the direction of arrival of unnecessary waves by the same procedure. That is, by detecting the angle f that is the minimum point of the received power of the receiver (7) within the angle θN instructed by the angle indicating circuit +10, the direction of arrival of a plurality of unnecessary waves can be detected, and the second As shown in the figure, by superimposing a pattern with a main beam in the direction of arrival of desired waves and the direction of arrival of unnecessary waves, a zero point can be formed in the direction of arrival of unwanted waves.

As described above, with the antenna device according to the present invention, a zero point can be formed in the arrival direction of unnecessary waves with a simple circuit configuration, and accurate signals can be obtained for communication and broadcasting in harsh radio wave environments. It has the effect that can be obtained.

[Brief explanation of drawings]

FIGS. 1(a), 1(b), and 1(c) are diagrams showing the operating procedure of the present invention. Figures 2 (a), (b), and (c) are diagrams showing the procedure for forming a zero point at a desired angle, and Figure 3 is a basic configuration diagram of an embodiment of the present invention. Antenna*(2+#i element antenna, (3) is an excitation distribution adjuster, (41 is an amplitude variable device, (5) is a phase shifter, (81ij sum circuit, (7) is a receiver, (81H detection circuit, (9) is a judgment circuit, ao is an unwanted wave arrival direction detection device, 01 is an arithmetic circuit, 匝 is a control circuit, and aS is a drive circuit. Agent Makoto Kuzuno - Figure 111 [C] Rattan 2aα)

Claims (1)

[Claims] (II) A plurality of element antennas, a phase shifter J connected to the element antennas, a control device for controlling each of the phase shifters, and an unnecessary wave arrival direction detection device l7. A circuit that calculates the excitation phase of each of the element antennas in order to form a zero point of a radiation pattern in the direction of arrival of unwanted waves using the radiation characteristics of the element antennas that are stored in advance and falsified as the detection results by the unwanted wave arrival direction detection device. In the antenna device having the unnecessary wave arrival direction detection device, the first zero point of the radiation pattern is formed at 7% in the direction of arrival of the desired wave, and the second zero point is formed in other directions, and As the second zero point scans the space, a signal for continuously calculating the excitation phase of the element antenna is sent to the arithmetic circuit @p, and a second point where the reception level of unnecessary waves is minimized is □. An antenna device characterized by using a device that knows the direction of arrival of unwanted waves from the direction of the zero point. An antenna device according to claim (1), which is defined as a symptom of a failure.