JPH0674979U - Wireless direction finding device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a direction detection device capable of performing direction detection with a small site error even in a relatively small site. [Structure] A large number of directional antennas with different directivity directions are arranged in a straight line or in an arbitrarily curved band-shaped zone,
The arrival direction of the radio wave is measured using the phase of the amplitude change of the signal of the detection signal obtained by switching the output of each antenna in a predetermined order.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a radio direction detecting antenna device in which a plurality of antennas having unidirectional directivity are arranged, and the direction of arrival of a radio wave is detected by an azimuth component in a detection signal obtained by switching the output of each antenna. Is.

[0002]

[Prior art]

 Such an antenna device has a disturbance error due to its arrangement condition, that is, a site error, and a method of reducing the error by increasing the outer diameter of the arrangement of the antenna device is described in, for example, Japanese Patent Laid-Open No. 60-80780. It is disclosed.

[0003]

[Problems to be solved by the device]

 The method of enlarging the layout of antennas as described above is effective as such, but it is necessary to secure a vast site. For this reason, there was a problem that it was difficult to put it into practical use because it was not possible to procure the necessary site easily due to problems such as land reclamation or location conditions.

[0004]

[Means for Solving the Problems]

 In this invention, a large number of directional antennas having different directivity directions are arranged at intervals in a linear or arbitrary curved band-like area, and the output of each antenna is switched in a predetermined order to obtain a change in signal amplitude of the detection signal. The above problem can be solved by a means for measuring the arrival direction of the radio wave using the phase of the as the azimuth component.

[0005]

【Example】

 Examples will be described below with reference to the drawings. In the figure, the area sandwiched between the boundary lines 1a and 1b is the outer line of the linear belt 3 or the curved belt-shaped belt 3. The antennas A1, A2, A3, A4, A7, and A8 are a group of antennas having a unidirectional directivity in the direction of the arrow in FIG. The antenna elements 101a, 101b, 102a, 102b, 103a, 103b, 104a, 104b, 105a, 105b, 106a, 106b, 107a, 107b, 108a, 108b of the antennas A1 to A8 are outside the boundary lines 1a, 1b. It is arranged as far as possible from the so-called disturbance interference installations 4a and 4b which disturb the direction detection by disturbing the propagation of radio waves or directly interfering with each antenna element.

Each of the antennas A1 to A8 is a unidirectional directional antenna such as the one described below. (1) A terminal resistor 201c is provided with one end 201a of the conductor plate 201 arranged parallel to the installation surface as shown in FIG. 2A as a termination point, and the other end 201b is used as a signal extraction point to obtain an output signal 201d. Flat type directional antenna. (This type of antenna is based on the "radiodirectional detection antenna" filed on September 25, 1986 by the applicant of this application.)

(2) The phase difference between the delayed output 202d delayed by the delay circuit 202c and the other output 202e on one output of the antenna elements 202a and 202b spaced apart as shown in FIG. 2B is taken out by the transformation circuit 202f. A delay-synthesizing directional antenna configured to obtain a phase difference output 202g. (This type of antenna is based on "Radio Direction Detecting Antenna Device" filed on Sep. 29, 1986 by the present applicant.) The antenna elements 202a and 202b may be configured by a loop antenna. Further, instead of taking out the phase difference as a phase difference output by the transformation circuit, it may be taken out as a detection signal by switching by the switching circuit. (This type of antenna is based on Japanese Patent Application No. 61-181237 “Simple type wireless direction finder” by the present applicant.)

(3) An output 203e obtained by synthesizing the phase difference output 203c by the well-known Adkkok antenna or loop antenna 203a as shown in FIG. 2C and the 90 ° phase output 203d of the output of the sense antenna 203b is obtained. Sense combining type directional antenna.

Here, a detection operation when the antenna of FIG. 2B is configured as each of the antennas A1 to A8 will be described. Looking at one of the antennas A1 to A8, the directivity is as shown in FIG. 3, and each antenna has a directivity line 101f, 102f, 103f, 104f, 105f, 106f, 107f, 108f. Since the directions are arranged differently, assuming that the differences are 45 ° each and the direction D of the incoming radio wave is 45 ° from the reference direction S 1, the output signals of the antennas A1 to A8 show the magnitude of the figure. This corresponds to the outputs 1c to 8c shown in FIG.

In FIG. 1, a switching circuit 11 switches and connects the respective antenna output signals 1c to 8c in a predetermined order (in the case of 1c, 2c ... 8c in the figure) by a switching signal 12a described later. The output thus obtained is output as the switching detection signal 11a. The switching wave circuit 12 is a signal for switching and connecting the antenna output signals 1c to 8c, and is a time series according to the above definition in the rectangular wave signal group (in the case of the figure, the pulse trains sequentially succeeding as shown in FIGS. ) Signal is output as the switching signal 12a. The switching detection signal 11a can be amplified and detected by the reception amplification circuit 13 and the AM detection circuit 14 to obtain the detection signal 14a (output signal of the detection circuit 14) of FIG.

The detection signal 14a has a size in each direction shown in FIG. 3 indicated by 1c to 8c and is arranged according to the switching signal 12a. The adjusting circuit 15 obtains the detection signal 14a from the switching detection signal 11a by the reception amplification circuit 13 or the like at the time point of the time-series signal from the switching wave circuit 12 so that the sampling timing described later is accurately performed. The sampling pulse signal is supplied to the sampling circuit 16 by adjusting the delay time up to. The sampling circuit 16 samples and outputs the analog value of the amplitude of the detection signal 14a at an appropriate time point near the middle of each of the above switching times, outputs the analog value by the A / D conversion circuit 17, and converts it into a digital value. 18 as an azimuth component data signal 17a.

The reference circuit 21 detects a signal time point when the time-series signal corresponding to the reference direction S in the switching signal 12 a of the switching wave circuit 12 is delay-adjusted by the adjusting circuit 15 and detects the signal time point as the reference time point data signal 21 a and outputs it to the processing circuit 18. give. The processing circuit 18 samples the azimuth component data signal 17a as the sampling value of the fundamental component of the signal waveform, that is, the azimuth component of the detection signal 14a shown in FIG. 93363 "Radio azimuth measuring method" and the like, and free phase expansion is performed to calculate the phase point of the fundamental wave component and output as the azimuth value signal 18a, which is displayed on the display circuit 19. The calculation of this phase point is performed using the reference time point signal 21a as a reference point. That is, the phase delay value of the waveform signal of the Sin wave or the Cos wave obtained by the azimuth component data signal 17a is calculated as the azimuth value with respect to the waveform signal of the Sin wave or the Cos wave having the reference time point data signal 21a as the starting point. ing.

[0013]

[Modified Example]

 This invention can be modified as follows. (1) The number of the antennas A1 to A8 to be arranged may be three or more, an appropriate number, and other circuit parts are modified according to the number. (2) The switching order of the antenna output signals 1c to 8c is appropriately changed to form an irregular or regular order such as 1c → 6c → 2c → 3c → 5c → 4c → 7c → 8c, and the processing circuit 18 In this case, the selection of the direction component data signal 17a is performed to replace the regular or irregular switching order with the normal order data.

(3) When installing on a moving body such as an automobile or a ship or on the roof of a building, the same arrangement as described above is applied with these places as the strip zones. (4) If the frequency of the radio wave is high such as 30 MHZ or higher, install a flat directional antenna or a delay-combined directional antenna when installing it on the roof of a car, etc., and on the ground or on the roof of a building at 30 MHZ or lower. When installing, a delay combining type directional antenna or a sense combining type directional antenna is applied.

[0015]

[Effect of device]

 According to the present invention, the height of a straight line or an arbitrary curved strip crosses the longitudinal direction, and in the arrangement of FIG. 1, there is little site error for radio waves coming from the left or right direction of the figure. Since it is possible to detect the direction of accuracy, it is only necessary to arrange so as to arrange according to the direction in which high accuracy is desired (in the case of a moving body, rotate the moving body in a direction that matches that direction). Even if there is, there is a feature that it is possible to perform direction detection with less detection error due to disturbing objects, that is, site error, even in a relatively small site, and in the case of a moving object, even at an equipment location corresponding to it.

[Brief description of drawings]

FIG. 1 is a block diagram of an installation example of an antenna and a device.

FIG. 2A is a diagram of a configuration example of an antenna that obtains unidirectional directivity.

FIG. 2B is a diagram of a configuration example of an antenna that obtains unidirectional directivity.

FIG. 2C is a diagram of a configuration example of an antenna that obtains unidirectional directivity.

[Fig. 3] Antenna directivity diagram

FIG. 4 is a signal waveform diagram of essential parts.

[Explanation of symbols]

 11 switching circuit 12 switching wave circuit 13 reception amplification circuit 14 AM detection circuit 15 adjustment circuit 16 sampling circuit 17 A / D conversion circuit 18 processing circuit 19 display circuit 21 reference circuit

Claims (4)

[Scope of utility model registration request] 1. A wireless direction finding device for locating a direction of arrival of a radio wave by arranging a plurality of antennas having unidirectional directivity, and switching an output of each antenna to detect an arrival direction of a radio wave by an azimuth component in a detection signal. a. Arranging means for arranging the antenna in a linear or curved strip-shaped zone or place with different directivities; b. Switching extraction means for obtaining the detection signal by switching and extracting the output of the antenna in a predetermined order, and c. Detecting signal means for obtaining a signal for detecting the arrival direction of a radio wave using the phase of the amplitude change of the signal in the detecting signal obtained by the switching extracting means as the azimuth component, and the site for arranging the antenna. A wireless direction finding device characterized by being able to reduce a site error in a direction range that is a main object even if there is the above restriction. 2. The apparatus according to claim 1, wherein the antenna is a flat plate type directional antenna. 3. The radio direction finding apparatus according to claim 1, wherein the antenna is a delay combining type directional antenna. 4. The device according to claim 1, wherein the antenna is a sense combining type directional antenna.