RU2505837C1 - Apparatus for processing signals of pulsed navigation radar - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: apparatus, having a pulsed transmitter of an antenna switch, a high frequency amplifier antenna, a mixer and an intermediate frequency amplifier, also includes a directional coupler, a frequency divider, a phase synchroniser and a frequency synthesiser, wherein the second output o the pulsed transmitter is connected through the coupler, through the frequency divider to the first input of the frequency synthesiser, having a second input connected through the phase synchroniser to the output of said frequency divider and having an output connected to the second input of the mixer.

EFFECT: enabling output of a coherent signal.

Description

The invention relates to the field of radar and can be used in a search system for objects.

A device for processing signals from a pulsed radar, which can be navigation, is presented in the book by Yu.M. Kazarinov. Radio engineering systems. M., Higher School, 1990, p. 194-197. In it, using a pulsed magnetron type transmitter, the formation of electromagnetic pulses is carried out, which through the antenna switch enters the antenna and is emitted into space. The electromagnetic energy reflected from the objects again enters the antenna and then through the aforementioned antenna switch into a high-frequency amplifier, where electromagnetic energy is converted into electrical signals. The latter enter the intermediate frequency amplifier through a mixer and an incoherent signal is produced. However, the device cannot provide a coherent signal.

A device is known for signal processing of a navigation pulse radar Pal-N1, presented in the book "Armament and Naval Equipment of Russia", Moscow, Publishing House Military Parade, 2003, p. 177.

It includes the same nodes as in the aforementioned analogue. However, it also cannot provide a coherent signal.

Using the proposed device provides the issuance of a coherent signal.

This is achieved by introducing a directional coupler, a frequency divider, a phase synchronizer and a frequency synthesizer, while the second output of the pulse transmitter is connected through a directional coupler, through a frequency divider to the first input of the frequency synthesizer having a second input connected through the phase synchronizer to the output of this frequency divider and having output connected to the second input of the mixer.

In figure 1 and in the text the following notation:

1 - pulse transmitter

2 - antenna switch

3 - antenna

4 - directional coupler

5 - high frequency amplifier

6 - frequency divider

7 - frequency synthesizer

8 - mixer

9 - phase synchronizer

10 - intermediate frequency amplifier.

 In this case, the first output of the pulse transmitter 1 is connected to the first input of the antenna switch 2, having a first output combined with the second input, and a second output, respectively connected to the combined input and output of the antenna 3, and through a high-frequency amplifier 5 with the first input of the mixer 8, having an output and a second input, respectively connected to the input of the intermediate frequency amplifier 10 and to the output of the frequency synthesizer 7, the first and second inputs of which are respectively connected through a frequency divider 6, a directional coupler 4 with the second output of the pulse transmitter 1 and through a phase 9 synchronizer with the output of the frequency divider 6.

The device operates as follows. Using a magnetron-type pulse transmitter 1, electromagnetic pulses are generated, which through the antenna switch 2, which prevents these pulses from entering the receiving nodes, enter the antenna 3 and are emitted into space. Electromagnetic energy reflected from surface or coastal objects is again supplied to the antenna 3 and then through the aforementioned antenna switch 2 to the high-frequency amplifier 5, where electromagnetic energy is converted into high-frequency electric signals and amplified. The latter are supplied to the first input of mixer 8. At the same time, the pulse transmitter 1, through a directional coupler 4, provides part of the energy to ensure the operation of newly introduced nodes that are not in the main analogue. Energy enters the frequency divider 6. The latter serves to obtain the necessary frequency for the local oscillator, whose functions are performed by the frequency synthesizer 7, where the pulse from the divider 6 is supplied. The frequency synthesizer 7 serves to reproduce the specified frequency, which can vary from pulse to pulse. The second input of the synthesizer 7 receives the signal of the phase 9 synchronizer, the input of which is connected to the output of the frequency divider 6 and the phase of the transmitter is linked to the phase of the synthesizer 7. The nature of the frequency change in the synthesizer 7 is similar to the nature of the frequency change in the amplifier 5. Therefore, at the output of the mixer 8 there is a coherent pulse signal that goes further into the intermediate frequency amplifier 10. Further, the signal can be further processed. An example of a specific implementation of the frequency synthesizer is presented in the aforementioned source by Yu.M. Kazarinov on page 312, Fig. 14.9. An example of the execution of a phase synchronizer is shown in Fig. 14.10.

Using the proposed device improves the functionality of the navigation radar, as it creates the ability to highlight the signals of moving objects against a background of passive interference. Thus, the efficiency of use of the device is increased.

Claims (1)

A signal processing device for a navigation pulsed radar, consisting of a pulsed transmitter, an antenna switch, an antenna of a high-frequency amplifier, a mixer and an intermediate frequency amplifier, where the output of the pulse transmitter is connected to the first input of the antenna switch having a first output combined with a second input and a second output, respectively connected to the combined input and output of the antenna, and through a high-frequency amplifier with the input of the mixer, the output of which is connected to the input of the amplifier daily frequency, characterized in that the following are introduced: a directional coupler, a frequency divider, a phase synchronizer and a frequency synthesizer, while the second output of the pulse transmitter is connected through a coupler, through a frequency divider to the first input of the frequency synthesizer having a second input connected through a phase synchronizer to the output this frequency divider and having an output connected to the second input of the mixer.