JPS62201380A - Azimuth measuring instrument - Google Patents

Abstract

PURPOSE:To measure the arrival azimuth of a radio wave twice at every turn of antennas by composing and sending a received signal obtained by rotating two antennas together to a single receiver and processing the output of the receiver by two processing circuit. CONSTITUTION:A transmit signal generated by a transmitter 31 is divided into two through a circulator 30 and a synthesizer 7, supplied to the sum beam terminals of the two antennas 1 and 2, and radiated in the air as sum beams 3 and 5. A reflected signal from the target, on the other hand, is received as a sum and a difference beam when the antennas 1 and 2 are directed to a target and they are sent to the receiver 9 through synthesizers 7 and 8 and a circulator 30. A receive signal from the same target is received by the antennas 1 and 2 once at every turn of the antennas and their receiving signals are processed by processing circuits 10a and 10b to measure their azimuths, so the same target is measured twice at every turn of the antennas.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a device for measuring the direction of arrival of received radio waves in radar, etc., and in particular to direction measurement that acquires data on the direction of arrival at a frequency greater than the number of rotations of an antenna. 〇 Regarding Apparatus (Prior Art) Conventionally, this type of direction measuring apparatus has a configuration shown in the block diagram in FIG. 3. 4(a) to 4(c) show each part (signal waveform) of the device in FIG. 3, and FIG. 4(d) shows the waveform of the
It is a figure which shows the measurement direction of the radio wave arrival direction in a figure device. In this device, the antenna 21 has two beams, an oro beam 22 and a differential beam 23, which rotate in a horizontal plane. Received on oro beam 22 and difference beam 23 (1
Nos. 26 and 27 are sent to the receiver 24. The receiver 24 is
A video signal 28 is generated whose amplitude corresponds to the ratio of the received signals by the Oro beam and the difference beam, ie, the gain ratio of the Oro beam and the difference beam, and whose polarity corresponds to the phase inversion of the difference beam phase. This video signal is sent to a processing circuit 25 where it is
The absolute value of the declination between the antenna pointing center azimuth and the received radio wave arrival direction is determined from the video amplitude, and the direction of the left or right is determined from the video (reliability) to determine the 4 angle 29.Next, this declination and The direction of arrival 30 for each pulse is determined from the antenna rotation angle, and the direction of arrival of the target radio wave is determined by averaging the series of pulse trains.Figure 4 (a)
In ~(d), the vertical axis indicates the signal amplitude, and the horizontal axis indicates the antenna rotation angle. The solid lines in the vertical direction in the figures (a) to (c) represent the amplitude and polarity of each signal at each reception pulse timing. The vertical broken line in FIG. 10(d) indicates the video signal 28 at the same reception pulse timing as in FIG. 2(a) to (c). In FIG. 4(d), the deflection angle 29 of each received pulse fσ is represented by a horizontal arrow. If the arrival direction of the received radio wave is 61, the video signal 28 is negative while the antenna rotation angle approaches 01, and the video signal 28 is positive when the antenna rotation angle is less than θ. The processing circuit 25 determines the declination angle 29 for each received pulse, and adds the declination angle 29 to the antenna rotation angle at that time (during a period in which the video signal 28 is negative) or subtracting it (during a period in which the video signal 28 is positive). , find the radio wave arrival direction 30 for each received pulse, and calculate the most likely received radio wave arrival direction θ by averaging the received command wave arrival direction 30 for each received pulse.
Find 1.

(Problems to be Solved by the Invention) In the conventional direction measuring device described above, the direction of arrival of the received radio waves is measured only once per one rotation of the antenna. A common method is to increase the However, since the number of revolutions is limited by the strength of the antenna, etc., there is a limit to the shortening of the measurement cycle.

(Means for making m points between points 4P) In order to solve the above-mentioned problems, the direction measuring device d provided by the present invention is a first
1 beam, and first and second beams whose axes of the directional characteristic pattern are approximately symmetrical in the azimuth direction with the beam as the center.
first and second antennas each having two beams with a difference beam consisting of a beam of generating video signals for the received signals of the first and second antennas independently of each other corresponding to the amplitude ratio of the received signals of the difference beams and whose polarity represents the phase of the difference beams; a receiver that outputs a video signal; and first and second processing circuits that receive the first and second video signals, respectively, the phase of the specified characteristic of the difference beam in the first and second antennas; are both about 180 degrees different from each other in the first and second beams;
The phases of the beam and the second beam are substantially the same as the second beam and the first beam of the optical difference beam in the second antenna, and the first and second antennas are attached to a common mount, the orobeams of the first and second antennas are in different directions, the difference beams of the first and second antennas are in different directions, and the first and second processing circuits and the second video signal [1] Determine the deflections of the axes of the 7-channel beams of the first and second antennas and the direction of arrival of the receiving radio waves, and determine the deflection of the first and second antennas at the time of generation of the video signal. The direction of arrival of the received radio waves is determined for each received pulse from the rotation angle of the second antenna and the deflection of these antennas, and the average direction information obtained by averaging the directions for a series of the received pulses is output. It is characterized by

(Example) Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing one implementation of the present invention,
2(a) to 2(C) are diagrams showing the 1M waveforms of each part of the embodiment in FIG. It is a figure explaining the measuring method of a wave arrival direction. In this implementation row, the first antenna 1 and the second antenna 2 are Orobeam 3,
5 and a differential beam 4°6, which are mounted on the same frame and rotate together in a horizontal plane. The respective Orobeam outputs of the first antenna 1 and the second antenna 2 are combined by a combination word 7 and sent to a receiver 9. The waveform of the signal output by the synthesizer 237 is shown in FIG. 2(a). In this figure, 11 is a received signal by the first antenna, and 12 is a received signal by the second antenna. On the other hand, the difference beam outputs of the first and second antennas 1 and 2 are combined by a combining cooler 8 and also sent to a receiver (receiving unit 9).

The waveform of this signal is shown in FIG. 2(b). In this figure,
13 is a first antenna, 14 is a second antenna, and the right and left phases of the beams of the rain antenna are opposite to each other.

Moreover, FIG. 2(c) shows the output of the receiver 9, and the first
Reception output by antenna 1 of 15 and second antenna 2
In the received output video 16, the increase/decrease in video amplitude as the antenna rotation angle advances is reversed.

This video output is sent to a first processing circuit LOa and a second processing circuit tab.

FIG. 2(d) explains the operation of the first processing circuit. Since the first processing circuit 10a performs processing in accordance with the differential beam phase of the first antenna 1, as shown in FIG. The direction of arrival of the radio wave determined from the declination angle and the angle of rotation of the antenna for each pulse approximately coincides with each other, and these are averaged and output as the direction of arrival of the radio wave. On the other hand, as shown in 18, for the received signal from the second aerial +W2 input to the second processing circuit 10a, the correction direction of the opening angle is reversed left and right, and the radio wave arrival directions determined for each pulse do not match, and the correlation is Since this is impossible, it is not detected as a vote.Similarly, the second processing circuit t
In ab, as shown in FIG. 2 (8), only the received signal 20 from the second antenna 2 is processed and output, while the received signal 19 from the first antenna 1 is not output. That is =
The angle measurement result from the aerial 5j11 of gt is sent from the processing circuit LOa of gt, and the angle measurement result from the second antenna 2 is sent to the second
Each is output from the processing circuit tab.

An example of a radar to which the embodiment shown in FIG. 1 is applied is shown in block form in FIG. In this radar, first, a transmission signal generated by a transmitter 31 is sent to a circulator 30, and then sent to a combiner 7 via this.

In the synthesis 2-diagnosis 7, the transmitted signal is divided into two parts, supplied to the to-beam terminals of the first antenna 1 and the second antenna 2, and radiated into space by the respective oro-beams 3 and 5. On the other hand, the reflected signals from the target are received by the combiner 7 and the output beam when each antenna is directed toward the target.
8 and the circulator 30 to the receiver 9.

The received 1d signal for the same target is received 1'd once each by the first and second antennas each time the antenna rotates once,
These received signals are processed by the processing circuit L for each type.
The orientation is measured by Oa and the processing circuit tab and output. That is, for each rotation of the antenna, the measurement for the same -0 yen is carried out twice.

(Effects of the Invention) As explained above, the present invention rotates two antennas together, combines the received signals obtained, sends this to a single receiver, and processes the output of the receiver in two ways. By processing in a circuit, the direction is measured by separating each two antennas again, so that the direction of arrival of the received radio waves can be measured twice for each rotation of the antenna.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 (
a) to (c) are waveform diagrams of various signals in the embodiment shown in FIG.
Figures (d) and (,) show the processing circuit 10 in this embodiment.
Fig. 3 is a block diagram showing a conventional azimuth measuring device a, and Fig. 4 (a) to (c) are waveforms of signals of various parts of the device jf in Fig. 3. FIG. 4(d) is a diagram showing the processing circuit 2 in the device shown in FIG.
FIG. 5 is a block diagram showing a radar using the fourth embodiment of FIG. 1. Agent Patent Attorney Shinsuke Honjo Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A sum beam whose directional characteristic pattern has a single axis; and a difference beam consisting of a first beam and a second beam whose directional characteristic pattern axis is substantially symmetrical in the azimuth direction about the sum beam. first and second antennas each having two types of beams, and a received signal from the sum and difference beams of the first and second antennas, and the received signal has an amplitude of the sum beam and the difference beam. and a polarity of which corresponds to an amplitude ratio of and whose polarity represents the phase of the difference beam is generated independently from each other for the received signals of the first and second antennas, and outputs the video signals as first and second video signals. and first and second processing circuits receiving the first and second video signals, respectively, wherein the phases of the directional characteristics of the difference beams in the first and second antennas are both equal to the first and second processing circuits.
and a second beam differing from each other by about 180 degrees, the first beam
The phases of the first beam and the second beam of the difference beam in the antenna are substantially the same as the second beam and the first beam of the difference beam in the second antenna, and
and a second antenna are mounted on a common mount,
The sum beams of the first and second antennas are in different directions, the difference beams of the first and second antennas are in directions A, and the first and second processing circuits are Determine the deflections of the oro beam axes of the first and second antennas and the direction of arrival of the received radio waves from the first and second video signals, and determine the deflections of the first and second antennas at the time when the video signals are generated. The azimuth of arrival of the received radio waves is determined for each received pulse from the rotation angle of the antenna and the polarization of these antennas, and the average azimuth information obtained by averaging the azimuths for a series of the received pulses is output. mullion measuring device.