JPS58113872A - Measuring device for direction of electric wave - Google Patents

Abstract

PURPOSE:To simplify the constitution of the device by a method wherein a false direction signal is removed based on the detected correlation of a plurality of directional angle scan reception levels and a directional angle whereat electric waves arrive is measured from the range of the true direction wherein the electric waves arrive. CONSTITUTION:While scanning the range of an object directional angle, a narrow beam aerial 11 catches an arriving electric wave and supplies the same to a receiver 13. An instantaneous reception level information is changed into a digital information, and a reception level is stored in a memory circuit 21 corresponding to an angle information sent from an angle encoder 17. Moreover, a correlation detecting circuit 22 reads out the stored data of the reception level in plural times from the reception level memory circuit 21 and when the true direction of the arrival of the electric wave is determined therefrom, the range of the true directional angle of the arrival of the electric wave is given as an instruction to the following operation circuit 23.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radio wave direction measuring device for measuring the direction of a radio wave emission source such as a radar. Conventionally, this type of radio wave arrival direction measuring device has been constructed as shown in the block diagram of FIG. It is configured.

That is, a signal received by a narrow beam directional antenna 11 whose pointing direction can be controlled is received and processed by a wide dynamic range receiver 13, and its reception level is supplied to a divider 15. On the other hand, the signal received by the omnidirectional antenna 12 is received and processed by a wide dynamic range receiver 14 having exactly the same characteristics as the reception a 13, and its reception level is supplied to a divider 15. Here, the signal level sent from the receiver 13 is divided by the signal level sent from the receiver 14. This divided signal is sent to the doubtful direction signal removal circuit 16, where if the signal level received by the receiver 13 is smaller than the signal level υ received by the receivers 4 & 14, the side lobe of the antenna 11 is detected. However, only when the signal level received by the receiver 13 is higher than the signal level received by the receiver 14 is the signal received by the main beam of the antenna 11. It is determined to be a signal and sent to the azimuth angle detection circuit 17.

The azimuth angle detection circuit 17 detects the radio wave arrival azimuth from the signal level received by the main beam of the antenna 11 and the antenna 1010 directional azimuth signal sent from the angle encoder 18.

This conventional azimuth detection device is a narrow beam directional aerial IVi
! 11, its wide dynamic range receiver 13, omnidirectional antenna 12, and its receiver 14, two systems of fc receivers are required, which have exactly the same characteristics, making the equipment extremely expensive. Since the difference in the gain of the antennas is used to remove doubtful orientations, there is a drawback that the characteristics of these antennas greatly limit the performance of removing doubtful orientations.

SUMMARY OF THE INVENTION An object of the present invention is to provide a radio wave direction measuring device which solves the above-mentioned drawbacks and is capable of measuring the direction of arrival of radio waves with a simple configuration of only one system of a narrow beam antenna and a receiver.

The radio wave direction measuring device of the present invention includes a directional antenna that can arbitrarily control the pointing direction and scans a predetermined angular range, an angle detection means for detecting the pointing direction of this antenna, and a detecting signal level received by the antenna. a memory circuit that stores signal level information of the receiver with respect to the directional direction of the antenna together with its angle information; and a correlation detection device that detects a correlation between the angle and signal level information of the memory circuit for each scan. and an angle calculation circuit which reads out the Th level information from the angular range of the output of the correlation detection circuit and calculates the arrival direction of the radio wave.

According to the configuration of the present invention, by scanning a narrow beam antenna multiple times in a predetermined angular range and correlating the changes in the reception level in each scan, suspicious bearings received by side lobes of the narrow beam antenna are detected. By determining the signal and finding the true direction of arrival of the radio wave, it is possible to calculate the central angle of the envelope of the piece in the air.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 2 is a block diagram of an embodiment of the invention. .

In the figure, a narrow beam aerial l# that can be controlled in any direction
A11, the wide dynamic range receiver 13 and the angle encoder 17 are the same as the conventional ones, and the reception level storage circuit 21, the correlation detection circuit 22, and the azimuth calculation circuit 2
3 is a new composition exploration.

Narrow beam aerial? The IM 11 captures incoming radio waves while scanning a target azimuth range and supplies them to the receiver 13. This receiving RGIF11IA performs reception processing over a wide dynamic range, converts instantaneous reception level information into digital information, and has a capacity that can store the received level by scanning the angle range for angle encoder multiple times. There is.

Furthermore, the correlation detection circuit 22 reads out the storage take of the reception level for each scan from the reception level storage circuit 21 for multiple times, and reads the reception level storage take for each scan multiple times, and reads the reception level for each scan over the angle range in which reception is received at a level equal to or higher than a preset threshold level. Alternatively, among the plurality of scans, the angle range in which more than a preset number of scans (b) are received is determined to be the true radio wave arrival direction, and the true radio wave arrival direction is determined for the next calculation (b) path 23. command the radio wave arrival azimuth angle range.

When the main beam of the antenna 11 faces the direction of the radio wave emission source,
While a signal that is higher than a preset threshold level is received each time, the reception level from the side lobe is higher than the threshold level due to radio wave emission source such as radar. Since this occurs at the instant when the main beam of the antenna directly faces the antenna 11, it is independent of the azimuth angle of the antenna 11. Therefore, the reception range for each scan of the antenna 11 is determined by the azimuth of arrival of the radio wave, and signals received from different azimuths for each scan are determined to be received from side lobes, and such received signals are excluded. In particular, doubtful bearing signals can be eliminated. The arithmetic circuit 23 reads information on the azimuth and reception level in the commanded angular range from the storage circuit 21, and calculates the center angle of the envelope of the directional characteristic of the narrow beam antenna to determine the accurate azimuth of arrival of the radio wave. I can do 6-.

As explained above, the present invention uses a narrow beam antenna that can be controlled in any direction, a wide dynamic receiver, a reception level storage circuit, a phase detection circuit, and an azimuth calculation circuit to perform multiple azimuth scans. It is possible to detect the correlation between reception levels, remove doubtful azimuth signals, and measure the radio wave arrival azimuth angle from the true radio wave arrival azimuth range. Therefore, compared to conventional devices, it can be configured more easily with one system of antennas and a receiving system. .

[Brief explanation of the drawing]

Figure 1 is a block diagram of a conventional receiving azimuth measurement device, Figure 2
The figure is a block diagram of an embodiment of the invention. In the figure, 11...Narrow heel tropic antenna, 1
2... Omnidirectional aerial deception, 13.14... Wide dynamic range receiver, 15... Divider, 1
6... Suspicious direction signal removal circuit, 17...
Angle encoder, 21... Reception level storage circuit, 22... Correlation detection circuit, 23 Gloss 1 Ward No. 7

Claims (1)

[Claims] A directional antenna whose pointing direction can be controlled arbitrarily and which scans a predetermined angular range; an angle detection means for detecting the pointing direction angle of the antenna; a receiver that detects the level of a received signal received by the antenna; a storage circuit that stores signal level information of the receiver with respect to the pointing direction and its angle information; a correlation detection circuit that detects a correlation for each scan with respect to the stored angle versus signal level information; A radio wave direction measuring device comprising: an angle calculation circuit that reads angle versus signal level information from the storage circuit from the output angle range and calculates a radio wave arrival direction.