JPH04110994U - radar receiver - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to effectively block unnecessary signals from the antenna when the automatic noise level control circuit is activated, and to improve the accuracy of receiving system gain setting. [Configuration] Amplifies the received signal from the antenna and
(Intermediate Frequency) signal
o Frequency) front end, an amplifier that amplifies the output signal of the RF front end, and an automatic noise level control circuit that is installed after the amplifier to prevent the signal noise level from changing due to fluctuations in the receiving system gain. Above RF
A power supply that supplies voltage to a low-noise amplifier in the front end, a local signal generator that supplies a local signal to a mixer in the RF front end, and a local signal generator to turn on and off the local signal to the RF front end and the power supply. It consists of a switch.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea is an automatic noise level control circuit (Automatic Noise Leveling, hereinafter referred to as A). When the NL circuit (called NL circuit) is activated, it effectively blocks unnecessary signals input from the antenna. The present invention relates to a radar receiver for cutting off signals.

0002

[Conventional technology]

A conventional device of this type is shown in FIG. In the figure, 1 is an antenna, and 2 is an IF signal for amplifying the signal from the antenna 1. The RF front end that converts the signal, 3, increases the signal from this RF front end 2. The amplifier 4, which increases the width of the signal, serves to keep the gain of the receiving system constant and prevent signal noise level fluctuations. 7 is the low ANL circuit that supplies the local signal to the RF front end 2. Cal signal generator.

0003 Next, the operation will be explained. The received signal from antenna 1 is amplified by RF front end 2 and converted into IF signal. The signal is converted and then amplified again by the IF amplifier 3 connected thereto. This I The ANL circuit 4 connected after the F amplifier 3 prevents electrical components from being affected by temperature. Because the performance of the receiving system changes, the gain of the receiving system changes and the level of signal noise changes. It can be prevented.

0004

[Problem that the idea aims to solve]

The conventional radar receiver as described above has the following problems. Sunawa In order to prevent ANL noise from changing due to AGC/STC voltage, ANL noise detection is During the output time, the AGC/STC voltage is maintained at 0V. Therefore, at the time of this detection, When receiving strong jamming, the ANL circuit detects only normal reception noise. Since it is impossible to do so, the receiving system gain will be set incorrectly. Note that the AGC voltage is the signal level In order to reduce tracking sensitivity fluctuations or tracking errors due to fluctuations in the search module, the STC voltage is These signals are applied to each mode to prevent saturation of the receiver at each mode.

[0005] This idea was made to solve the above problems, and it Provides a radar receiver that effectively blocks unnecessary signals from an antenna when the antenna is in motion. It is.

[0006]

[Means to solve the problem]

In the radar receiver according to this invention, the low noise amplifier in the RF front end The power supply that supplies voltage and the local signal to the RF front end are connected to the ANL circuit. By blocking during operation, the influence of unnecessary signals such as jamming signals and clutter signals is reduced. It was designed to be as small as possible.

[0007]

[Effect]

The radar receiver in this invention has an RF front end when the ANL circuit is activated. power supplies supplying voltage to low-noise amplifiers within the board and local to the RF front end. Since the signal is blocked, there is no need for jamming signals or clutter signals input to the receiving system. The signal is suppressed and the accuracy of receiving system gain setting is improved.

[0008]

【Example】

Example 1. An embodiment of this invention will be described below with reference to the drawings. In Figure 1, 1 is an antenna, 2 is an RF front end, 3 is an amplifier, and 4 is an A NL circuit, 5 is a switch, 6 is a power supply, 7 is a local signal generator, 8 is a control signal line It is.

[0009] The operation of this idea will be explained. When ANL circuit 4 operates, antenna 1 Unwanted signals such as jamming signals and clutter signals received by the RF front end 2 - Passes through amplifier 3 and inputs to ANL circuit 4, detecting only regular reception noise This prevents incorrect gain settings due to the impossibility of I made it possible to control. In other words, when ANL circuit 4 is activated, the control signal from 4 is controlled. The switch 5 is turned off via the control signal line 8, and low noise amplification within the RF front end 2 is performed. By cutting off the power supply to the device and the local signal to the RF front end. , the unnecessary signal from the antenna 1 is greatly suppressed, and the ANL circuit 4 receives it. This allows only the noise generated by the communication system to be detected.

0010

[Effect of the idea]

As described above, according to this invention, the low noise amplifier in the RF front end is When the ANL circuit is activated, the local signal to the power supply and RF front end is This prevents jamming when the ANL circuit is activated, compared to conventional radar receivers. Unnecessary signals such as traffic signals can be ignored. Therefore, by properly operating the ANL circuit, This has the effect of improving the accuracy of setting the desired value.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a radar receiver according to the invention.

FIG. 2 is a block diagram of a conventional radar receiver.

[Explanation of symbols]

1 antenna 2 RF front end 3 Amplifier 4 ANL circuit 5 switch 6 Power supply 7 Local signal generator 8 Control signal line

Claims (1)

[Scope of utility model registration request] Claim 1: An RF (R
adio Frequency) front end, an amplifier that amplifies the output signal of the RF front end, and an automatic noise level control circuit that is installed after the amplifier to prevent the signal noise level from changing due to fluctuations in the receiving system gain. A power supply that supplies voltage to a low noise amplifier in the RF front end, a local signal generator that supplies a local signal to a mixer in the RF front end, and a local signal generator that supplies a local signal to the RF front end and the power supply. A radar receiver characterized by an off switch.