KR20040047059A - Apparatus for generating imitation target of radar - Google Patents

Abstract

PURPOSE: An apparatus for generating a simulated target of radar is provided to perform a simulation of a moving target by using a simulated target signal generated from the radar. CONSTITUTION: An apparatus for generating a simulated target of radar includes a time gate signal generation unit, a first directional coupler, an RF switch, a phase shifter, a variable attenuator, an isolator, and a second directional coupler. The time gate signal generation unit(110) receives a TX-TRIG signal, transmits a target TX-TRIG signal to a transmission unit, outputs an RF switching signal and a phase shift switching signal. The first directional coupler(120) is used for separating a radar pulse modulation signal from the transmission unit. The RF switch(130) is switched according to the RF switching signal in order to transmit only a simulated target signal. The phase shifter(140) is used for shifting periodically a phase of the radar pulse modulation signal. The variable attenuator(150) is used for attenuating the intensity of the phase-shifted pulse signal. The isolator(160) is used for transmitting signals to the traveling direction and removing the signals opposite to the traveling direction. The second directional coupler(170) is used for transmitting the output signals of the isolator to a front-end part of an antenna.

Description

Radar simulated target generator {APPARATUS FOR GENERATING IMITATION TARGET OF RADAR}

The present invention relates to a radar, and more particularly, to a simulated target generator of a radar that enables the simulation of the radar without the need to radiate a high power RF signal of the radar using a transceiver in the radar.

In general, radar (Radar Detection and Ranging) is a sensor that detects the presence of objects at a distance beyond human visual field limits, and has all-weather functions regardless of weather conditions or day and night, and from a short distance to the horizon beyond the horizon. Because of the unique signal characteristics that can detect long-range objects, it is a completely different electromagnetic sensor than conventional methods.

Radar is an all-weather electronic eye that uses electromagnetic waves to see long-range targets. Early warning, port monitoring, as well as civil use, such as air navigation and control, earth and space exploration, meteorological observation, ship navigation, vehicle speed measurement, and collision avoidance. It is used for military purposes such as air defense, air defense, and missile guidance control.

On the other hand, such a radar simulates by launching a real target for simulation, or simulates by installing a mock target outside a certain distance, or generates a mock target signal from an external dedicated device and inputs a signal to the radar input terminal. Proceed with the simulation.

However, this simulation has a problem in that it costs a lot of money because it simulates a real target or installs a mock target and uses an external dedicated equipment using expensive high-frequency components.

In addition, when mock targets are installed externally, they are fixed to two types for 100m and 4km, and detection by various distance changes is impossible, and target signals cannot be measured because the target signals are fixed, and high-power RF signals can be detected from actual radar. Another problem is that electromagnetic waves leak due to transmission.

Accordingly, an object of the present invention is to solve the above problems, and generates a simulated target signal in the radar by the distance control signal, and converts a low output RF signal by the distance control signal to an appropriate level in the simulated target generator. Since the radar does not actually transmit a high power RF signal by inputting the radar, the risk of electromagnetic waves is reduced, and the target speed can be changed freely according to the distance control signal, thereby enabling the simulation of the moving target.

In addition, another object of the present invention is to provide a low-cost, compact, lightweight mock target generator without separately using external dedicated equipment using expensive high-frequency components.

1 is a block diagram schematically showing the configuration of a radar system to which the simulated target generator of the radar is applied according to the present invention;

Figure 2 is a timing diagram showing the output signal of each component of the simulated target generator of the radar according to the present invention

<Description of the symbols for the main parts of the drawings>

10 radar 11: signal processing unit

12: transmitting unit 13: power amplifying unit

14 antenna front end 15 receiver

100: simulated target generator 110: time gate signal generator

120: first directional coupler 130: RF switch

140: phase shifter 150: variable attenuator

16: Isolator 170: Second Directional Coupler

180: signal check terminal

Features of the present invention for achieving the above object,

In a radar comprising a signal processor, a transmitter, a power amplifier, an antenna front end, and a receiver,

The target TX_TRIG signal, which is a simulated target pulse signal to be tested, is received from the transmitter by a TX_TRIG signal, which is a transmission command pulse, and is output to the transmitter, and the simulation target radar pulse modulated signal is output from the transmitter due to the input of the target TX_TRIG signal. Outputs a RF switching signal to pass only the simulated target signal included in the time gate signal, and outputs a phase shifted switching signal to make the simulated target radar pulse modulation signal generated by passing only the simulated target signal to the Doppler signal. Generation part,

A first directional coupler for separating a mock target radar pulse modulated signal output from the transmitter;

An RF switch switched according to an RF switching signal output from the time gate signal generator and configured to pass only a simulated target signal among the simulated target radar pulse modulation signals output from the first directional coupler;

The mock target radar pulse is switched according to a phase shift switching signal output from the time gate signal generator to convert the mock target radar pulse modulated signal passed through the RF switch into a Doppler signal similar to an actual moving target signal. A phase shifter for periodically changing a phase of a modulated signal,

A variable attenuator for reducing the intensity of the phase modulated pulse signal output from the phase shifter to enable a minimum detection test of the radar;

An isolator for transmitting only the signals necessary for the test by passing a signal in a traveling direction among the pulse signals output from the variable attenuator and removing leakage power in a reverse direction;

And a second directional coupler for transmitting a signal output through the isolator to a reception path of the front end of the antenna.

Here, at one output end of the first directional coupler,

The signal check terminal used for fault and check is connected.

Hereinafter, the configuration of the simulated target generator of the radar according to the present invention will be described in detail with reference to FIG.

1 is a block diagram schematically showing the configuration of a radar system to which a simulated target generator of a radar is applied according to the present invention.

First, the radar 10 includes a signal processor 11, a transmitter 12, a power amplifier 13, an antenna front end 14, and a receiver 15.

Referring to FIG. 1, the simulated target generator 100 of the radar according to the present invention includes a time gate signal generator 110, a first directional coupler 120, an RF switch 130, and a phase shifter. 140, a variable attenuator 150, an isolator 160, a second directional coupler 170, and a signal check terminal 180.

The time gate signal generator 110 receives the TX_TRIG signal, which is a transmission command pulse, from the radar transmitter 12 and outputs a target TX_TRIG signal, which is a simulated target pulse signal, to be tested to the transmitter 12. In addition, the time gate signal generator 110 outputs an RF switching signal to pass only the simulated target signal included in the simulated target radar pulse modulation signal output from the transmitter 12 due to the input of the target TX_TRIG signal. In addition, the time gate signal generator 110 outputs a phase shift switching signal to make the simulated target radar pulse modulation signal generated by passing only the simulated target signal as a Doppler signal. Here, the time gate signal generator 110 uses a digital circuit using a digital element therein to perform signal generation, time delay, etc. according to timing.

The first directional coupler 120 separates the simulated target radar pulse modulated signal output from the transmitter 12.

The RF switch 130 is switched according to the RF switching signal output from the time gate signal generator 110 and passes only the simulated target signal among the simulated target radar pulse modulation signals output from the first directional coupler 120.

The phase shifter 140 is switched in accordance with the phase shift switching signal output from the time gate signal generator 110 and a Doppler signal similar to a target signal that actually moves a simulated target radar pulse modulation signal that has passed through the RF switch 130. The phase of the mock target radar pulse modulated signal is periodically changed to vary with.

The variable attenuator 150 reduces the intensity of the phase modulated pulse signal output from the phase shifter 140 to allow for the minimum detection test of the radar.

The isolator 160 transmits only a signal necessary for the test by passing a signal in a traveling direction among the pulse signals output from the variable attenuator 150 and removing leakage power in the reverse direction.

The second directional coupler 170 transmits the signal output through the isolator 160 to the reception path of the antenna front end ().

The signal checking terminal 180 is connected to one output terminal of the first directional coupler 120 to enable a fault and check.

Hereinafter, the configuration of a simulated target generator of a radar according to the present invention will be described in detail with reference to FIGS. 1 and 2.

Figure 2 is a timing diagram showing the output signal of each component of the simulated target generator of the radar according to the present invention.

First, the transmitting unit 12 of the radar is to generate a pulse modulated signal as a transmitting command pulse, but the transmission command pulse as shown in FIG. 2A of FIG. The TX_TRIG signal is input to the time gate signal generator 110. Here, A of FIG. 2 is a transmission pulse (TTL) signal.

Then, the signal is converted into a target TX_TRIG signal, which is a simulated target pulse signal to be tested as shown in B of FIG. 2, by the internal digital circuit of the time gate signal generator 110, and then input to the transmitter 12. Here, B of FIG. 2 is a signal in which a pulse corresponding to a moving target (approach / retreat) is received using an internal digital circuit of the time gate signal generator 110 when an existing transmission pulse is input as a transmission pulse signal in a simulation test. .

In this case, the radar pulse modulation signal is generated by the TX_TRIG signal of the transmitter 12 in the actual operation mode, not the test mode. In the simulated test mode, the radar pulse is generated by the target TX_TRIG signal of the time gate signal generator 110. Since the modulated signal is generated, the low output transmitter of the transmitter 12 outputs a simulated target radar pulse modulated signal such as C of FIG. 2. 2C is an RF signal in which pulse modulation is generated at the transmitter 12 by the moving target (access / retreat) pulse signal.

The simulated target radar pulse modulated signal is input to the RF switch 130 through the first directional coupler 120.

Then, the RF switch 130 is switched according to the RF switching signal as shown in FIG. 2D output from the time gate signal generator 110 and FIG. 2 of the mock target radar pulse modulation signals output from the first directional coupler 120. Only simulated target signals such as E are passed through and input to the phase shifter 140. Here, D of FIG. 2 is a signal for operating the RF switch 130 to pass only the simulated target signal because the existing transmission signal and the simulated movement target (access / retreat) signal coexist, and FIG. It is a pulse modulated RF signal.

In addition, the phase shifter 140 is switched according to a phase shift switching signal as shown in FIG. 2F output from the time gate signal generator 110 to simulate the radar pulse modulation signal for the simulated target passing through the RF switch 130. The phase of the simulated target radar pulse modulated signal is periodically changed to vary the Doppler signal similar to the actual moving target signal to output a phase modulated pulse signal as shown in FIG. Here, F of FIG. 2 is a command signal for turning on / off a phase shifter to produce a Doppler signal, and G of FIG. 2 is a simulated moving pulse modulated signal including a Doppler signal 25k.

Then, the variable attenuator 150 reduces the intensity of the phase modulated pulse signal output from the phase shifter 140 so as to enable the minimum detection test of the radar as shown in FIG. Here, H of FIG. 2 is a transmission pulse signal that is 10 to -110 dBm variable to allow the minimum detection test of the radar.

Since the isolator 160 receives the intensity-reduced pulse signal and passes the signal in the forward direction and removes the leakage power in the reverse direction, only the transmission pulse signal necessary for the test is transmitted. This signal is again passed through the second directional coupler 170 and then input to the antenna front end () of the radar through the receiving path of the antenna front end 14 to the receiver 15 and the same as the normal operation mode of the radar. Radar simulation is performed by performing signal processing.

Therefore, by using the pulse signal generated from the radar to generate the desired target target signal, through the radar itself to generate a simulated target signal and output it by amplifying a certain level in the simulated target generator and then input to the antenna side of the radar again The desired simulated moving target can be easily measured.

As described above, according to the simulated target generator of the radar according to the present invention, the simulated target signal is generated by the radar by the distance control signal, and the low output RF signal by the distance control signal is converted to an appropriate level by the simulated target generator. Since the radar does not actually transmit a high power RF signal by inputting it to the radar again, the risk of electromagnetic waves is reduced, and the target speed can be changed freely according to the distance control signal, so that the simulation of the moving target can be performed. It is possible to provide a low cost, small sized mock target generator without separately using external equipment using high frequency components.

Claims (2)

In a radar comprising a signal processor, a transmitter, a power amplifier, an antenna front end, and a receiver, The target TX_TRIG signal, which is a simulated target pulse signal to be tested, is received from the transmitter by a TX_TRIG signal, which is a transmission command pulse, and is output to the transmitter, and the simulated target radar pulse modulation signal is output from the transmitter due to the input of the target TX_TRIG signal. Outputs a RF switching signal to pass only the simulated target signal included in the time gate signal, and outputs a phase shifted switching signal to make the simulated target radar pulse modulation signal generated by passing only the simulated target signal to the Doppler signal. Generation part, A first directional coupler for separating a mock target radar pulse modulated signal output from the transmitter; An RF switch switched according to an RF switching signal output from the time gate signal generator and configured to pass only a simulated target signal among the simulated target radar pulse modulation signals output from the first directional coupler; The mock target radar pulse is switched according to a phase shift switching signal output from the time gate signal generator to convert the mock target radar pulse modulated signal passed through the RF switch into a Doppler signal similar to an actual moving target signal. A phase shifter for periodically changing a phase of a modulated signal, A variable attenuator for reducing the intensity of the phase modulated pulse signal output from the phase shifter to enable a minimum detection test of the radar; An isolator for transmitting only the signals necessary for the test by passing a signal in a traveling direction among the pulse signals output from the variable attenuator and removing leakage power in a reverse direction; And a second directional coupler for transmitting a signal output through the isolator to a receiving path of the front end portion of the antenna. The method of claim 1, At one output end of the first directional coupler, Simulated target generator of the radar, characterized in that the terminal for checking the signal used in the failure and inspection is connected.