Abstract:
A microwave frequency converter for a radar receiver is provided in which a frequency of a local oscillator of the microwave frequency converter can be prevented from interfering with an oscillation frequency of a magnetron included in the radar receiver and which can receive a signal from a considerably short distance. A voltage of an RF amplifier connected to the microwave frequency converter is synchronized with an oscillation output of the magnetron. The gate and drain voltages of a FET used in the RF amplifier are simultaneously switched OFF only during times before and after the magnetron performs oscillation, thereby switching an amplification function of the FET to an attenuation function thereof to increase a switching loss of the microwave frequency converter. Thereby, an excessively large power RF signal directly input from the magnetron and an excessively large power RF signal reflected from a short distance are attenuated to prevent the microwave frequency converter from being saturated, and the frequency of the local oscillator from interfering with the oscillation frequency of the magnetron.
Abstract:
A radar apparatus having an integral ARPA function transmits at least two kinds of pulse signals, each of which has different pulselength, according to a specific transmission pattern and receives echoes of the transmitted pulse signal. The radar apparatus includes an echo data generator for generating display echo data for each range scale selected for on-screen presentation by using an echo signal obtained with each transmission pulselength, an ARPA processor for generating a single set of motion-related information on each tracked target to be superimposed on the display echo data by using echo signals obtained with the different pulselengths, a display output synthesizer for superimposing the motion-related information on each tracked target generated by the ARPA processor on the display echo data, and a display unit for displaying a superimposed picture produced by the display output synthesizer.
Abstract:
A radar device is disclosed, which includes an antenna for transmitting an electromagnetic wave and receiving an echo signal from a target object while rotating in a horizontal plane, a display module for displaying the target object so as to correspond the echo signal to a position of the target object with respect to the antenna, a speed calculation module for calculating a relative velocity of the antenna and the target object, and a risk level detection module for detecting a risk level of the target object based on the relative velocity of the target object calculated by the speed calculation module. The speed calculation module calculates the relative velocity of the target object based on a change in phases of at least two of the echo signals received at a different time. The display module controls a display mode of the target object based on the risk level.
Abstract:
A radar apparatus having an integral ARPA function transmits at least two kinds of pulse signals, each of which has different pulselength, according to a specific transmission pattern and receives echoes of the transmitted pulse signal. The radar apparatus includes an echo data generator for generating display echo data for each range scale selected for on-screen presentation by using an echo signal obtained with each transmission pulselength, an ARPA processor for generating a single set of motion-related information on each tracked target to be superimposed on the display echo data by using echo signals obtained with the different pulselengths, a display output synthesizer for superimposing the motion-related information on each tracked target generated by the ARPA processor on the display echo data, and a display unit for displaying a superimposed picture produced by the display output synthesizer.
Abstract:
A radar apparatus transmits a pulse signal including pulses having at least two different pulselengths in a specific transmit pulse pattern and receives a returning echo signal through a single antenna. A tuning voltage setting timing generator generates a timing of setting a tuning voltage according to a combination of transmission pulselengths and a tuning processor performs tuning operation in a manner suited to a current transmission pulselength based on the tuning voltage setting timing. The radar apparatus may include a tuning voltage alteration decider for deciding whether or not to alter the tuning voltage based on a combination of alternate pulselengths before altering the pulselength of the pulse signal generated by a transmitter and the tuning processor alters the tuning voltage based on the result of decision made by the tuning voltage alteration decider.
Abstract:
A microwave frequency converter for a radar receiver is provided in which a frequency of a local oscillator of the microwave frequency converter can be prevented from interfering with an oscillation frequency of a magnetron included in the radar receiver and which can receive a signal from a considerably short distance. A voltage of an RF amplifier connected to the microwave frequency converter is synchronized with an oscillation output of the magnetron. The gate and drain voltages of a FET used in the RF amplifier are simultaneously switched OFF only during times before and after the magnetron performs oscillation, thereby switching an amplification function of the FET to an attenuation function thereof to increase a switching loss of the microwave frequency converter. Thereby, an excessively large power RF signal directly input from the magnetron and an excessively large power RF signal reflected from a short distance are attenuated to prevent the microwave frequency converter from being saturated, and the frequency of the local oscillator from interfering with the oscillation frequency of the magnetron.
Abstract:
A radar device is disclosed, which includes an antenna for transmitting an electromagnetic wave and receiving an echo signal from a target object while rotating in a horizontal plane, a display module for displaying the target object so as to correspond the echo signal to a position of the target object with respect to the antenna, a speed calculation module for calculating a relative velocity of the antenna and the target object, and a risk level detection module for detecting a risk level of the target object based on the relative velocity of the target object calculated by the speed calculation module. The speed calculation module calculates the relative velocity of the target object based on a change in phases of at least two of the echo signals received at a different time. The display module controls a display mode of the target object based on the risk level.
Abstract:
A radar apparatus transmits a pulse signal including pulses having at least two different pulselengths in a specific transmit pulse pattern and receives a returning echo signal through a single antenna. A tuning voltage setting timing generator generates a timing of setting a tuning voltage according to a combination of transmission pulselengths and a tuning processor performs tuning operation in a manner suited to a current transmission pulselength based on the tuning voltage setting timing. The radar apparatus may include a tuning voltage alteration decider for deciding whether or not to alter the tuning voltage based on a combination of alternate pulselengths before altering the pulselength of the pulse signal generated by a transmitter and the tuning processor alters the tuning voltage based on the result of decision made by the tuning voltage alteration decider.
Abstract:
The portion corresponding to a main bang signal leaking from a transmission/reception switching unit is extracted as a frequency estimation signal from an IF signal from a mixer in a signal extracting unit, a frequency is estimated in a frequency estimating unit, and the frequency of a local oscillation signal of a local oscillator is controlled so that the frequency of the IF signal is equal to a target value. The frequency estimation in the frequency estimating unit is carried out by using Discrete Fourier Transform or Fast Fourier Transform.
Abstract:
The portion corresponding to a main bang signal leaking from a transmission/reception switching unit is extracted as a frequency estimation signal from an IF signal from a mixer in a signal extracting unit, a frequency is estimated in a frequency estimating unit, and the frequency of a local oscillation signal of a local oscillator is controlled so that the frequency of the IF signal is equal to a target value. The frequency estimation in the frequency estimating unit is carried out by using Discrete Fourier Transform or Fast Fourier Transform.