JPH0366629B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a monopulse angle measuring device using, for example, an SSR (secondary surveillance radar device).

[Technical background of the invention]

In general, an antenna with a monopulse radiation pattern (sum pattern and difference pattern) in the azimuthal plane is
A change in elevation changes the gain and the correlation between the sum-difference patterns.

With conventional monopulse angle measurement equipment, the relationship between the multi-system receiver output voltage and the deviation azimuth angle of the sum pattern from the beam nose direction is determined from the monopulse pattern (sum and difference pattern) in the maximum gain direction in the vertical plane of the antenna radiation pattern. (usually referred to as an S curve) and maintain this value as a table,
A method is used to detect the output of the received signal from a multi-system receiver and convert this voltage value into an azimuth.

[Problems with background technology]

However, since this method uses the horizontal radiation pattern at one elevation angle in the vertical plane as a reference, the accuracy of measuring the azimuth angle of an aircraft in this elevation angle direction is high, but it is difficult to measure the azimuth angle of an aircraft at a different elevation angle. The disadvantage is that the angle measurement accuracy is low.

[Purpose of the invention]

The present invention has been made to eliminate the above-mentioned conventional drawbacks, and an object of the present invention is to provide a monopulse angle measuring device in which the angle measuring accuracy does not deteriorate even at each elevation angle.

[Summary of the invention]

The monopulse angle measuring device of the present invention calculates the elevation angle of the target from the target's altitude information and distance information, and corrects the read azimuth angle value based on the calculated elevation angle information.

[Embodiments of the invention]

Embodiments of the monopulse angle measuring device of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of one embodiment.
The figure shows a system diagram when a monopulse angle measurement function is added to a conventional SSR device. 1 in FIG. 1 is a monopulse antenna, and a signal from an SSRR transmitter 2 is radiated into the air as radio waves through this monopulse antenna 1.

This monopulse antenna 1 has a monopulse angle measurement radiation pattern (sum pattern and difference pattern) within the azimuth plane, and rotates continuously within the azimuth plane.

An SSR multi-system receiver 3 is connected to the monopulse antenna 1, which transmits a signal containing response code information from a transponder mounted on the aircraft and a signal containing aircraft azimuth information to an information processing device 4 at the next stage. Send to. The information processing device 4 includes a code decoding section 5, a monopulse angle measurement section 6, and an elevation angle calculation section 7.
It is composed of.

Next, the operation of the monopulse angle measuring device of the present invention configured as described above will be explained. Radio waves emitted from the SSR transmitter 2 through the monopulse antenna 1 (an example of a horizontal radiation pattern is shown in FIG. 2) are received by a transponder mounted on an aircraft. The response signal from this transponder is
Received by the monopulse antenna 1, the received signal difference pattern Δ and the received signal sum pattern Σ are each independently supplied to the SSR multi-system receiver 3.

This SSR multi-system receiver 3 processes both the difference, sum Δ, and Σ signals of the received signals, and has a Σ signal with response code information (altitude information and identification information of the aircraft) and a azimuth information (Δ/ Σ) Generates a signal and supplies it to the next stage information processing device 4.

A code decoder 5 in the information processing device 4 decodes the response code (altitude and identification) from the Σ signal.
From this code decoding section 5, altitude information of the aircraft and distance information from the antenna to the aircraft are sent to an elevation angle calculation section 7.
supplied to The elevation angle calculation unit 7 calculates the elevation angle of the aircraft from the altitude information and the distance information, and supplies the calculation result to the monopulse angle measurement unit 6.

The monopulse angle measurement section 6 detects the azimuth of the aircraft from the (Δ/Σ) signal under the control of the code decoding section 5. At this time, the read azimuth angle is determined based on the elevation angle information obtained by the elevation calculation section 7. Give correction to the value.

This can be corrected by, for example, preparing multiple voltage and azimuth angle tables for each elevation angle and changing the table depending on the elevation angle, or changing the azimuth angle value obtained from the basic table depending on the elevation angle. There are methods such as multiplying by coefficients. This makes it possible to accurately obtain the azimuth angle of the aircraft at each elevation angle.

〔Effect of the invention〕

As described above, according to the monopulse angle measurement device of the present invention, the elevation angle of the target is calculated from the target altitude information and distance information, and the read azimuth angle value is corrected based on the calculated elevation angle information. As a result, it is possible to prevent the angle measurement accuracy from decreasing due to changes in the elevation angle of the target, which has a great practical effect.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the monopulse angle measuring device of the present invention, and FIG. 2 is a diagram showing an example of the horizontal radiation pattern of the monopulse antenna in the same monopulse angle measuring device. 1... Monopulse antenna, 2... SSR transmitter, 3... SSR multi-system receiver, 4... Information processing device, 5... Code decoding section, 6... Monopulse angle measuring section, 7... Elevation angle calculation Department.

Claims (1)

[Claims] 1. A monopulse antenna that has a monopulse angle measurement radiation pattern in the azimuth plane and receives a response signal from a target in response to the emitted radio waves, and a monopulse antenna that receives the signal from the monopulse antenna and receives the response code information of the target. a receiver for outputting a signal having the azimuth information and a signal having the azimuth information of the target; means to which the signal having the azimuth information is supplied and extracting the azimuth value of the target; a means of decoding the target's altitude information;
an elevation calculation unit that calculates the elevation angle of the target from this altitude information and distance information from the antenna to the target; and correcting the azimuth angle value to a value corresponding to the elevation angle based on the elevation angle information from the elevation calculation unit. A monopulse angle measuring device comprising means.