JP2000338212A - Azimuth and position detecting equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detecting equipment capable of azimuth detection and position detection of a radio wave transmitting source with high precision. SOLUTION: This detecting equipment is provided with two directional antennas 1, 2 different in the plane of polarization which can interlock and rotate in the state that a desired angle of elevation is maintained, a phase sum and difference synthesizing circuit 3 outputting the sum and the difference of antenna patterns of the two antennas 1, 2, a differential gain adjusting unit 4 adjusting the gain of difference component, a receiver 5 receiving the sum component of the synthesizing circuit 3, a receiver 6 receiving an output of the adjusting unit 4, a subtractor 7 subtracting detected signal outputs of the receivers 5, 6, and a calculating unit 8 determining the azimuth and the position of an arrival radio wave on the basis of an output of the subtractor 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an azimuth / position detecting device capable of receiving a radio wave and specifying its arrival direction and position with high accuracy.

[0002]

2. Description of the Related Art As a basic azimuth detecting device for detecting the direction of arrival of a radio wave, there is a device for detecting the direction of arrival of a radio wave using a directional antenna such as a Yagi antenna.
Further, there is a direction detection device using an omnidirectional antenna and a directional antenna, such as a direction detection device proposed in Japanese Patent Application No. 3-67789.

[0003]

Since the conventional azimuth detecting device is configured as described above, it can detect only the arrival direction of the radio wave. Further, since the azimuth detection accuracy is limited by the beam width of the directional antenna, high-precision detection cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is intended to detect the direction of arrival of radio waves with high accuracy, and to detect not only the azimuth but also the position with high accuracy. It is an object of the present invention to provide an azimuth / position detection device that can perform the operation.

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, an azimuth / position detecting apparatus according to the present invention comprises two directional antennas having different polarization planes which can rotate in conjunction with each other with a desired elevation angle. Phase sum difference synthesizing means for outputting the sum and difference of the antenna patterns of the two directional antennas;
Differential gain adjusting means for adjusting the gain of the differential component of the antenna pattern; first receiving means for receiving the sum component of the phase sum / difference combining means; and second receiving means for receiving the output of the differential gain adjusting means. The apparatus comprises a receiving means, a subtracting means for subtracting detection signal outputs of the first and second receiving means, and a calculating means for determining an azimuth and a position of an incoming radio wave from an output of the subtracting means. With this configuration, the direction of arrival of the radio wave can be detected with high accuracy, and the position of the radio wave emission source can be specified with high accuracy.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention according to claim 1 of the present invention provides two directional antennas having different polarization planes that can rotate in conjunction with each other with a desired elevation angle, and the two directional antennas. Phase sum difference combining means for outputting the sum and difference of the antenna pattern, difference gain adjusting means for adjusting the gain of the difference component of the antenna pattern, and a first sum receiving means for receiving the sum component of the phase sum difference combining means. Receiving means, a second receiving means for receiving the output of the differential gain adjusting means, a subtracting means for subtracting the detection signal outputs of the first and second receiving means, and a radio wave arriving from the output of the subtracting means. Azimuth / position detecting device comprising a calculation means for determining the azimuth and the position of the radio wave, and determining the azimuth and the position of the emission source of the radio wave from the sum output and the difference output of the antenna patterns of two directional antennas. Action A.

According to a second aspect of the present invention, in the azimuth / position detecting device according to the first aspect, the azimuth / position detecting device in which the polarization planes of the two directional antennas are horizontal polarization and vertical polarization. This has the effect of determining the azimuth and position of the emission source of the radio wave from the sum output and the difference output of the antenna pattern of the directional antenna of horizontal polarization and the antenna pattern of the directional antenna of vertical polarization.

According to a third aspect of the present invention, in the azimuth / position detecting apparatus according to the first aspect, the phase sum / difference synthesizing means combines the positions of the two directional antennas when synthesizing the sum and the difference. An azimuth / position detecting device capable of setting a phase difference, and determines an azimuth and a position of a radio wave emitting source from a sum output and a difference output of an antenna pattern of two directional antennas synthesized by shifting a phase difference. It has the action of:

According to a fourth aspect of the present invention, in the azimuth / position detecting apparatus according to the first aspect, the azimuth / position determining the position of the radio wave emitting source by adjusting the gain of the difference component of the antenna pattern. This is a detection device that determines the direction of arrival of the radio wave by rotating the two directional antennas in conjunction so as to maximize the sum output, and adjusts the elevation angle while adjusting the gain of the differential output to determine the radio wave. Has the effect of determining the position of the launch source.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a position / azimuth detecting apparatus to which the present invention is applied. This position / direction detection device
Directional antenna 1 for horizontal polarization and directional antenna 2 for vertical polarization
And The directional antenna 1 and the directional antenna 2 can rotate in conjunction with each other with a predetermined elevation angle. The phase sum difference combining circuit 3 receives the received signal of the directional antenna 1 and the received signal of the directional antenna 2 and generates and outputs a sum signal and a difference signal of the two received signals. Here, when combining the sum signal and the difference signal, the phase sum difference combining circuit 3 can set the phase difference between the two directional antennas 1 and 2 to a desired value. The gain adjustment circuit 4 adjusts the gain of the difference signal output from the phase sum difference synthesis circuit 3. The receiver 5 detects the sum signal output from the phase sum / difference synthesizing circuit 3, and the receiver 6 detects the sum signal.
The differential signal after the gain adjustment output from is detected. The subtractor 7 calculates the difference between the detection output of the receiver 5 and the detection output of the receiver 6. The calculator 8 calculates the arrival direction and position of the radio waves received by the directional antennas 1 and 2 based on the output of the receiver 5 and the output of the subtractor 7.

FIG. 2 shows a phase sum difference combining circuit 3 in FIG. 1 in which the phases of the reception signals of the directional antennas 1 and 2 are shifted by λ / 4 from each other to synthesize a sum signal, and the difference signals are shifted by 3λ / 4 from each other. Shows the case where is synthesized. Hereinafter, the operation will be described with reference to FIG.

In FIG. 2, a horizontally polarized directional antenna 1 and a vertically polarized directional antenna 2 which rotate in an interlocking direction, which are directed in the same direction and have a predetermined directivity and whose elevation angle can be adjusted, are respectively connected. A received signal (hereinafter, an antenna pattern) corresponding to the polarization pattern is output.

The antenna patterns of the directional antennas 1 and 2 are input to a phase-sum-difference synthesizing circuit 3 and mutually λ /
A sum output (hereinafter referred to as a Σ pattern) synthesized by shifting by four,
This is divided into a difference output (hereinafter, Δ pattern) synthesized by shifting by 3λ / 4 from each other. Each pattern is shown in FIG. In FIG. 3, α is an azimuth angle.

The Δ pattern output from the phase sum / difference synthesizing circuit 3 is input to a gain adjusting circuit 4 where the gain is adjusted and then input to a receiver 7. On the other hand, the Σ pattern is directly input to the receiver 5. The receivers 5 and 6 output the detection signals of the sum output and the difference output to the subtracter 7, respectively. The subtractor 7 subtracts the detection signal of the difference output from the detection signal of the sum output, generates an angular characteristic (hereinafter, Σ−Δ pattern) of the difference, and outputs the angle characteristic to the calculator 8.

As is clear from the Σ pattern and the Δ pattern shown in FIG. 3, the Σ-Δ pattern, which is the difference between them, has a sharp level change near the front of the antenna. This means that the beam width of the antenna is equivalently narrower than the Σ pattern. Therefore, by using the output corresponding to the Σ-Δ pattern, it is possible to perform azimuth detection with higher accuracy. Further, by adjusting the gain of the Δ pattern in the gain adjustment circuit 4, the Σ-Δ pattern can be shifted. An example is shown in FIG. By this gain adjustment, it is possible to detect the maximum point of the arrival position of the radio wave.

Next, an example of a procedure for detecting the arrival direction and position of a radio wave will be described. The calculator 8 calculates the level of the Σ pattern while rotating the directional antenna 1 and the directional antenna 2 and determines the azimuth at which the level becomes maximum,
Detect the direction of arrival of radio waves. Further, the output of the Δ pattern is adjusted using the gain adjuster 4 and the elevation angle of the directional antennas 1 and 2 is adjusted at the same time to determine the position.

FIG. 5 shows an embodiment in which the azimuth / position of a radio wave emission source in the direction of extension of a road is measured by the azimuth / position detecting device to which the present invention is applied. In this figure, the upper part is a plan view and the lower part is a side view. As shown in this figure, when a directional antenna is installed on the lane of a road and the direction of extension of the road is measured, the directional antenna has an elevation angle to determine the measurement zone of the road surface. Then, by adjusting the azimuth angle so as to maximize the 位置 pattern, the position of the radio wave emission source can be measured.
If the range (width) of the road is wide, the position of the radio wave emitting source can be measured by rotating the directional antenna to the left and right in the horizontal direction.

FIG. 6 is a plan view showing another embodiment. For example, when it is desired to specify the position of the radio wave emission source on the lane from one measurement point away from a certain road, the measurement range of the road surface is determined by giving the directional antenna an elevation angle. Then, by adjusting the azimuth angle so as to maximize the Σ pattern of the directional antenna, the position range of the radio wave emission source can be measured. Further, by adjusting the elevation angle of the directional antenna and rotating the antenna horizontally to the left and right, it becomes possible to measure the position of the radio wave emission source in a wide range of the lane.

[0020]

As described above, according to the present invention, the direction of arrival of radio waves is determined by rotating the two directional antennas in conjunction with each other so as to maximize the Σ pattern of the two directional antennas, Since the position of the emission source of the radio wave is determined by adjusting the elevation angle while adjusting the gain of the output of the Δ pattern, the effect that high accuracy azimuth detection and position detection can be performed with a simple antenna configuration is obtained. Can be

[Brief description of the drawings]

FIG. 1 is a block diagram showing an azimuth / position detecting apparatus to which the present invention is applied;

FIG. 2 is a block diagram of a phase sum difference synthesis circuit for calculating Σ and Δ patterns of two directional antennas, and a block diagram before and after the phase sum difference synthesis circuit;

FIG. 3 is an explanatory diagram showing an example of a Σ pattern and a Δ pattern;

FIG. 4 is an explanatory view showing adjusting a gain of a Δ pattern;

FIG. 5 is a diagram showing an embodiment in which the position is determined by adjusting the gain of the Σ-Δ pattern,

FIG. 6 is a diagram showing another embodiment in which the position is determined by adjusting the gain of the Σ-Δ pattern.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 directional antenna for horizontal polarization 2 directional antenna for vertical polarization 3 phase sum difference synthesis circuit 4 gain adjustment circuit 5, 6 receiver 7 subtractor 8 calculator

Claims (4)

[Claims] 1. A phase-sum difference for outputting a sum and a difference of two directional antennas having different polarization planes rotatable in association with each other with a desired elevation angle, and an antenna pattern of the two directional antennas. Combining means, differential gain adjusting means for adjusting the gain of the difference component of the antenna pattern, first receiving means for receiving the sum component of the phase sum / difference combining means, and receiving the output of the differential gain adjusting means Second receiving means, subtracting means for subtracting detection signal outputs of the first and second receiving means, and calculating means for determining an azimuth and a position of an incoming radio wave from an output of the subtracting means. An azimuth / position detection device characterized by the following. 2. The azimuth / position detecting apparatus according to claim 1, wherein the polarization planes of the two directional antennas are horizontal polarization and vertical polarization. 3. The azimuth / position detecting device according to claim 1, wherein the phase sum / difference synthesizing means can set a phase difference between two directional antennas when synthesizing the sum and the difference. . 4. The azimuth / position detecting device according to claim 1, wherein the position of the radio wave emitting source is determined by adjusting the gain of the difference component of the antenna pattern.