RU2366970C1 - Radiolocator - Google Patents

Abstract

FIELD: physics, measurements.

SUBSTANCE: radiolocator is designed for searching of objects at large distances. Technical result is achieved due to introduction of receiving antenna with crossing directional patterns, giant-pulse metre of azimuth, permanent memory, subtractor and unit of secondary processing, besides receiving antenna with crossing directional patterns is rigidly connected to narrow-band transmitting antenna and has group of inputs connected via giant-pulse metre of azimuth with the second group of subtractor inputs and via permanent storage with the first group of inputs of secondary processing unit, having group of outputs and the second group of inputs, which are accordingly connected to the first group of indicator inputs and with group of subtractor outputs, which is also connected to the second group of indicator inputs and having group of inputs connected to group of azimuth detector outputs.

EFFECT: increased accuracy of definition of distance to object.

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Description

The invention relates to the field of radar and can be used to search for objects located at long ranges.

Known radar, presented as a device for processing radar signals, described in the patent of the author No. 2096798 of February 16, 1996. In it, using a single-frequency unmodulated continuous signal transmitter, the formation of electromagnetic energy entering the transmitting antenna is carried out. The antenna rotates in a circular view. The range is determined after the arrival of the signal reflected from the object by analyzing the envelope and displayed on the indicator. However, the accuracy of determining the range is not always sufficient.

Known radar set forth in the patent of the author No. 2161806. In it, with the help of a transmitter of a single-frequency unmodulated continuous signal, electromagnetic energy is generated that enters the transmitting antenna that is emitted into space. The antenna rotates in the circular viewing mode using a drive rigidly connected to the azimuth sensor. The range is defined as the difference in the duration of the signals from the object when the antennas rotate at one or the other speed. In this case, the range and direction are displayed on the indicator. However, the range is determined in a time equal to two space surveys.

Using the proposed device, the range is determined during one review without reducing the accuracy of its determination. This is achieved by introducing a receiving antenna with intersecting radiation patterns, a monopulse azimuth meter, read-only memory, a subtractor and a secondary processing unit, while a receiving antenna with intersecting radiation patterns is rigidly connected to a narrowly directed transmitting antenna and has a group of outputs connected via a monopulse azimuth meter to a second the group of inputs of the subtractor and through a read-only memory with the first group of inputs of the secondary processing unit, having a group of outputs and a second group of inputs, respectively connected to the first group of inputs of the indicator and to the group of outputs of the subtractor, also connected to the second group of inputs of the indicator and having the first group of inputs connected to the group of outputs of the azimuth sensor.

In the drawing and in the text, the following notation:

1 - transmitter single-frequency unmodulated continuous

signal;

2 - narrowly directed transmitting antenna;

3 - receiving antenna with intersecting diagrams

directionality;

4 - monopulse azimuth meter;

5 - drive;

6 - read-only memory;

7 - azimuth sensor;

8 - subtractor;

9 - block secondary processing;

10-indicator

in this case, the receiving antenna with intersecting radiation patterns 3 is rigidly connected to a narrowly directed transmitting antenna 2 and has a group of outputs connected via a monopulse azimuth meter 4 to the second group of inputs of the subtractor 8 and through read-only memory 6 to the first group of inputs of the secondary processing unit 9 having a group outputs and a second group of inputs, respectively connected to the first group of inputs of the indicator 10 and to the group of outputs of the subtractor 8, also connected to the second group of inputs of the indicator 1 0 and having a first group of inputs connected to the group of outputs of the azimuth sensor 7, rigidly connected to the drive 5, having a rigid connection with a narrowly directed transmitting antenna 2, having an input connected to the output of the transmitter of a single-frequency unmodulated continuous signal 1.

The operation of the device is as follows.

Using a transmitter of a single-frequency unmodulated continuous signal 1, a signal is generated that enters a narrowly directed transmitting antenna 2, which generates electromagnetic energy emitted into space. Electromagnetic energy reflected from the object enters rigidly connected to the transmitting receiving antenna with intersecting radiation patterns.

An example of a receiving antenna with intersecting radiation patterns is presented in the book "Radio Engineering Systems". Yu.M. Kazarinov. M., 1990, p. 252, 409. The antennas rotate using drive 5, rigidly connected with the azimuth sensor 7. Moreover, the receiving antenna 3 can be rotated relative to the transmitting antenna 2 in the opposite direction to rotation. The magnitude of the rotation of the receiving antenna depends on the speed of rotation of the antenna and on the maximum detection range, which determines the width of the intersection zone of the receiving antenna diagrams 3. The signals from the group of outputs of the receiving antenna 3 are fed to the group of inputs of the single-pulse azimuth meter 4, where they are converted into electrical signals, which can stand out according to the characteristics corresponding to the expected moving objects. By determining the ratio of the maximum amplitudes of the signals, the azimuthal position of the object is determined in the zone of intersection of the radiation patterns of the receiving antenna 3. The number of intersecting patterns can be two or more.

An example of the execution of a single-pulse azimuth meter is presented in the book by A.I. Leonov, K.I. Filippov. "Monopulse radar." 1984, Radio and Communications, pp. 12-14, Fig. 1.3 and 1.5c. It can be a part of a direction finding device with the aforementioned intersecting radiation patterns and can operate in a circular viewing mode, as well as provide encoded information for further processing, as noted in the aforementioned book by Yu.M. Kazarinova on pp. 412-413.

The azimuthal position of the object in the zone of intersection of the diagrams also characterizes the distance to the object. This is explained by the fact that the intersection zone of the diagrams at the moment of arrival of the maximum of the reflected signal will rotate by a value proportional to the distance to the object, since the maximum signal, coinciding in time with its amplitude, is formed as a result of irradiating the object with the maximum power of electromagnetic radiation when the object is on a vertical the plane on which the central axis of the transmitting antenna 2 is also located. Therefore, the direction to the object is characterized at the time of this exposure. It is defined as follows. The code from the group of outputs of the multipulse range meter 4 is supplied to the second group of inputs of the subtractor 8, where it is subtracted from the azimuth code from the azimuth sensor 7, and the difference from the group of outputs of the subtractor 8, characterizing the azimuthal direction to the object, is fed to the second group of inputs of the secondary processing unit 9. In addition, the code from the aforementioned group of outputs of the monopulse range meter 4 also arrives at the group of inputs of the permanent storage device 6. This code, in addition to the azimuthal direction in the zone of intersecting gram as bears and range information. At the same time, groups of codes that are sewn up to the corresponding specific encoded ranges enter the read-only memory. The number of codes in each group depends on the range resolution. The azimuth sensor 7 can be performed as noted in patent No. 2186406 under the name "Sensor of azimuth marks", where the information repetition rate should correspond to the azimuth resolution of the intersection zone of the radiation patterns of the receiving antenna 3. This resolution also characterizes the accuracy of determining the range. For example, if in the diagram crossing zone it is equal to 0.005 of the zone width, and the controlled range is 1000 km, then the accuracy of determining the range will be 2 km. However, it can be clarified during the secondary processing. The range code from the group of outputs of the permanent storage device 6 is supplied to the first group of inputs of the secondary processing unit 9, where the construction of the trajectories of the movement of targets. At the same time, their range is clarified, since an average trajectory is built and the accuracy of determining the distance at a distance of 1000 km can be 0.5-1 km.

An example of the execution of the secondary processing unit is presented in the book "Radio Engineering Systems". 1985, V.B. Pestryakov et al., P. 219, where it is noted that the secondary processing unit is part of the computer, where the range and azimuth can come in the form of parallel codes. It is also noted that in the secondary processing unit there is a smoothing out of errors received in the current and previous review cycles, which ensures the refinement of previously received range information.

The proposed device can be used to detect space objects, as well as in air traffic control systems at the expected sections of the ranges of extended paths. When using Doppler bandpass filters in a single-pulse azimuth meter that do not change the amplitude of the signals, a measurement of the distance to many objects with different radial velocities in the radiation pattern of the transmitting antenna is provided.

Compared to pulsed radars, the detection range increases when using a transmitter with increased signal emission power. At the same time, the weight and dimensions of the product are many times less than when using a pulse transmitter, which allows the device to be used in airborne and mobile carriers.

Thus, a positive effect is provided.

Claims (1)

A radar consisting of a transmitter of a single-frequency unmodulated continuous signal, a narrowly directed transmitting antenna, a drive, an azimuth sensor and an indicator, where the output of a transmitter of a single-frequency unmodulated continuous signal is connected to an input of a narrowly transmitted transmitting antenna, which is rigidly connected to the drive, which has a rigid connection with the azimuth sensor, characterized in that a receiving antenna is introduced with intersecting radiation patterns, a single-pulse azimuth meter, read-only memory in, a subtractor and a secondary processing unit, while the receiving antenna with intersecting radiation patterns is rigidly connected to a narrowly directed transmitting antenna and has a group of outputs connected via a monopulse azimuth meter with a second group of subtractor inputs and through a permanent storage device with the first group of inputs of the secondary processing unit, having a group of outputs and a second group of inputs, respectively connected to the first group of inputs of the indicator and to the group of outputs of the subtractor, also connected to Ora group indicator inputs and having an input group connected to the group azimuth sensor outputs.

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