KR102592703B1 - Radar apparatus - Google Patents

Abstract

A radar device according to an embodiment of the present invention includes a controller configured to generate a variable delay control signal whose value varies with time, a transmission clock, and a delay time that varies according to the variable delay control signal. A clock generator configured to generate a delayed receive clock, a transmitter configured to radiate a transmit pulse through a transmit antenna based on the transmit clock, receive a first echo pulse through a first receive antenna in which the transmit pulse is reflected from a target, and receive a receive clock. Receive a second echo pulse in which the transmission pulse is reflected from the target through a first receiver and a second receiving antenna configured to generate a first recovery signal corresponding to the first echo pulse based on the first echo pulse, and receive a second echo pulse based on the receiving clock A second receiver configured to generate a second recovery signal corresponding to the echo pulse, wherein the controller determines a first delay time between a transmit clock corresponding to the first recovery signal and a receive clock and a transmit clock corresponding to the second recovery signal. and obtain the distance of the target based on at least one of a second delay time between the received clock and the received clock.

Description

RADAR APPARATUS

The present invention relates to a radar device, and more specifically, to a pulse radar device that emits pulses based on a clock signal and obtains information about the target from the pulse reflected from the target.

A pulse radar apparatus can repeatedly emit a transmission pulse based on a transmission clock and restore an echo pulse that is returned by reflecting the transmission pulse to a target based on a reception clock. The pulse radar device can obtain information about the target by analyzing the restored echo pulse.

The pulse radar device can acquire target distance and target azimuth information by analyzing echo pulses. In order to accurately obtain the target's distance (i.e., to achieve high range resolution), the delay between the transmit clock and the receive clock must be finely adjusted. However, it is not easy to finely control the delay between the transmit clock and the receive clock. Additionally, in order to precisely acquire the azimuth of a target (i.e., to implement high azimuth resolution), a pulse radar device may include a plurality of receivers disposed at various locations. However, when a pulse radar device includes multiple receivers, the size of the radar device may be large and power consumption may be high.

The present invention is intended to solve the above-mentioned technical problems. The purpose of the present invention is to provide high range resolution by finely adjusting the delay between the transmit and receive clocks of a pulse radar device. Additionally, the goal is to provide high azimuth resolution while minimizing the size of the pulse radar device.

A radar device according to an embodiment of the present invention includes a controller configured to generate a variable delay control signal whose value varies with time, a transmission clock, and a delay time that varies according to the variable delay control signal. A clock generator configured to generate a delayed reception clock, a transmitter configured to radiate a transmission pulse through a transmission antenna based on the transmission clock, and receiving a first echo pulse through a first reception antenna where the transmission pulse is reflected from a target; , receiving a second echo pulse in which the transmission pulse is reflected from the target through a first receiver and a second reception antenna configured to generate a first recovery signal corresponding to the first echo pulse based on the reception clock, a second receiver configured to generate a second restored signal corresponding to the second echo pulse based on the received clock, and the controller configured to generate a second recovery signal between the transmit clock and the receive clock corresponding to the first restored signal. and obtain the distance of the target based on at least one of a delay time and a second delay time between the transmit clock and the receive clock corresponding to the second recovery signal.

In one embodiment, the controller may be further configured to obtain the azimuth of the target based on the separation distance between the first receiving antenna and the second receiving antenna, the first delay time, and the second delay time. You can.

In one embodiment, the separation distance may be more than half the wavelength of the center frequency of the transmission pulse.

In one embodiment, the variable delay control signal may continuously change between a preset minimum value and a preset maximum value.

In one embodiment, the clock generator includes a first delay element configured to generate the transmit clock by delaying a reference clock based on a first delay control signal, and delaying the reference clock based on a second delay control signal. A second delay element configured to generate the receive clock, a phase comparator configured to compare the phase of the transmit clock and the phase of the receive clock to output a phase comparison output signal, and the difference between the phase comparison output signal and the variable delay control signal. It may include an error amplifier configured to amplify and output the second delay control signal.

In one embodiment, the first receiver and the second receiver each include a low noise amplifier configured to amplify a received echo pulse of the first echo pulse and the second echo pulse, and the amplification in response to the received clock. A sampler configured to sample an echo pulse and output a sampled signal, a variable amplifier configured to amplify the sampled signal, and convert the amplified sampled signal into a digital signal to produce the first restored signal and the first restored signal. 2 may include an analog-to-digital converter configured to output one of the recovery signals.

In one embodiment, a transmitter may include an oscillator configured to change the center frequency and bandwidth of the transmit pulse.

In one embodiment, the variable delay control signal is generated according to a predetermined period, and the controller may be further configured to output a control period signal synchronized to the predetermined period.

A radar device according to an embodiment of the present invention includes a controller configured to generate a variable delay control signal whose value varies with time, a transmission clock, and a delay time that varies according to the variable delay control signal. A clock generator configured to generate a delayed receive clock, a first transmitter configured to radiate a first transmit pulse through a first transmit antenna based on the transmit clock, and a second transmit pulse through a second transmit antenna based on the transmit clock. Receive at least one echo pulse in which the first transmission pulse and the second transmission pulse are reflected from a target through a second transmitter and a reception antenna configured to radiate a pulse, and transmit the at least one echo pulse based on the reception clock. and a receiver configured to generate at least one recovery signal corresponding to, wherein the controller is configured to obtain the distance of the target based on a delay time between the transmit clock and the receive clock corresponding to the at least one recovery signal. It is more structured.

In one embodiment, the controller is further configured to obtain the azimuth of the target based on the information analyzed from the waveform of the at least one restored signal and the separation distance between the first and second transmit antennas. It can be.

In one embodiment, the variable delay control signal may continuously change between a preset minimum value and a preset maximum value.

In one embodiment, the clock generator includes a first delay element configured to generate the transmit clock by delaying a reference clock based on a first delay control signal, and delaying the reference clock based on a second delay control signal. A second delay element configured to generate the receive clock, a phase comparator configured to compare the phase of the transmit clock and the phase of the receive clock to output a phase comparison output signal, and the difference between the phase comparison output signal and the variable delay control signal. It may include an error amplifier configured to amplify and output the second delay control signal.

In one embodiment, the receiver includes a low noise amplifier configured to amplify the received echo pulse, a sampler configured to sample the amplified echo pulse in response to the reception clock and output a sampled signal, It may include a variable amplifier configured to amplify a sampled signal, and an analog-to-digital converter configured to convert the amplified sampled signal into a digital signal and output the restored signal.

A radar device according to an embodiment of the present invention includes a controller configured to generate a variable delay control signal whose value varies with time, a transmission clock, and a delay time that varies according to the variable delay control signal. A clock generator configured to generate a delayed reception clock, a transmitter configured to radiate a transmission pulse through a transmission antenna based on the transmission clock, and receiving a first echo pulse through a first reception antenna where the transmission pulse is reflected from a target; , receiving a second echo pulse in which the transmission pulse is reflected from the target through a first receiver and a second reception antenna configured to generate a first recovery signal corresponding to the first echo pulse based on the reception clock, a second receiver configured to generate a second recovery signal corresponding to the second echo pulse based on the received clock, and the controller is configured to generate the first recovery signal at a minimum distance detection point for a period of the variable delay control signal. of the target based on at least one of a first time ratio until the restoration time of the signal and a second time ratio from the minimum distance detection time to the restoration time of the second recovery signal for the period of the variable delay control signal. It is further configured to obtain distance.

In one embodiment, the controller determines the azimuth of the target based on the difference between the distance of the first target obtained using the first time ratio and the distance of the second target obtained using the second time ratio. It may be further configured to obtain.

In one embodiment, the clock generator includes a first delay element configured to generate the transmit clock by delaying a reference clock based on a first delay control signal, and delaying the reference clock based on a second delay control signal. A second delay element configured to generate the receive clock, a phase comparator configured to compare the phase of the transmit clock and the phase of the receive clock to output a phase comparison output signal, and the difference between the phase comparison output signal and the variable delay control signal. It may include an error amplifier configured to amplify and output the second delay control signal.

In one embodiment, the first receiver and the second receiver each include a low noise amplifier configured to amplify a received echo pulse of the first echo pulse and the second echo pulse, and the amplification in response to the received clock. A sampler configured to sample an echo pulse and output a sampled signal, a variable amplifier configured to amplify the sampled signal, and convert the amplified sampled signal into a digital signal to produce the first restored signal and the first restored signal. 2. It may include an analog-to-digital converter configured to output a corresponding restoration signal among the restoration signals.

In one embodiment, the variable delay control signal may be a sawtooth wave-shaped signal that linearly increases or decreases between the preset minimum value and the preset maximum value.

In one embodiment, the variable delay control signal may be a signal that non-linearly increases or decreases between the preset minimum value and the preset maximum value.

The pulse radar device according to an embodiment of the present invention can acquire the target distance and target azimuth with high resolution.

Additionally, according to an embodiment of the present invention, a miniaturized pulse radar device can be provided, and an integrated pulse radar device can be implemented with low power.

1 is a diagram showing the schematic operation of a radar device according to an embodiment of the present invention.
FIG. 2 is a block diagram showing an example of the radar device of FIG. 1.
3A and 3B show examples of variable delay control signals generated from the controller of FIG. 2.
FIG. 4 is a diagram showing examples of clocks and pulses generated according to the variable delay control signal of FIG. 3A.
FIG. 5 is a diagram showing examples of restoration signals received by the controller of FIG. 2 and a control period signal (CPS) output from the controller.
FIG. 6 is a diagram showing how the controller of FIG. 2 acquires the distance and azimuth of the target.
FIG. 7 is a block diagram showing the clock generator of FIG. 2.
FIG. 8 is a block diagram showing the receiver of FIG. 2.
Figure 9 is a flowchart showing the operation of a radar device according to an embodiment of the present invention.
Figure 10 is a flowchart showing the operation of a radar device generating a transmission clock and a reception clock according to an embodiment of the present invention.
FIG. 11 is a block diagram showing another embodiment of the radar device of FIG. 1.
FIG. 12 is a diagram showing an example of a restored signal generated from the radar device of FIG. 11.
FIG. 13 is a diagram showing how the controller of FIG. 11 obtains the distance and azimuth of the target.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. In the following description, details such as detailed configurations and structures are provided simply to facilitate an overall understanding of embodiments of the present invention. Therefore, modifications to the embodiments described in the text can be made by those skilled in the art without departing from the technical spirit and scope of the present invention. Furthermore, descriptions of well-known functions and structures are omitted for clarity and conciseness. The terms used in this specification are terms defined in consideration of the functions of the present invention, and are not limited to specific functions. Definitions of terms may be determined based on the details described in the detailed description.

Modules in the following drawings or detailed description may be connected to components other than those shown in the drawings or described in the detailed description. Connections between modules or components may be direct or non-direct, respectively. The connection between modules or components may be a communication connection or a physical connection, respectively.

Unless otherwise defined, all terms including technical or scientific meanings used in the text have meanings that can be understood by those skilled in the art to which the present invention pertains. In general, terms defined in dictionaries are interpreted to have a meaning equivalent to the contextual meaning in the relevant technical field, and are not interpreted to have an ideal or excessively formal meaning unless clearly defined in the text.

1 is a diagram showing the schematic operation of a radar device according to an embodiment of the present invention. Referring to FIG. 1, the radar device 100 may emit a transmission pulse (TP). Alternatively, the radar device 100 may transmit a transmission pulse (TP) toward the target. For example, the transmission pulse (TP) may include electromagnetic waves such as radio waves, infrared rays, visible rays, ultraviolet rays, X-rays, and gamma rays.

The radar device 100 may receive an echo pulse (EP) in which the transmission pulse (TP) is reflected and returned to the target. The radar device 100 may obtain information about the target by analyzing the echo pulse (EP). Illustratively, the radar device 100 is configured to measure the distance (R) from the radar device 100 to the target (hereinafter referred to as the distance (R) of the target) or the azimuth angle (θ) formed between the radar device 100 and the target. (hereinafter referred to as the azimuth angle (θ) of the target) can be obtained.

Targets may include stationary objects and moving objects. The radar device 100 can obtain the position information and speed information of the object by acquiring the distance (R) and azimuth (θ) of the fixed object and the moving object.

As an example, the radar device 100 may radiate a transmission pulse (TP) based on a transmission clock and restore the received echo pulse (EP) based on a reception clock. The radar device 100 can adjust the target range by controlling the delay time between the transmission clock and the reception clock. For example, a first delay time between a transmit clock and a receive clock may correspond to a first distance to a target, and a second delay time between a transmit clock and a receive clock may correspond to a second distance to a target. Accordingly, when the echo pulse (EP) is restored, the radar device 100 can obtain the distance (R) of the target based on delay information between the transmission clock and the reception clock.

The radar device 100 can obtain the distance (R) of the target with high resolution by finely controlling the delay time between the transmission clock and the reception clock. A detailed description of the operation of the radar device 100 to acquire the distance (R) of the target will be described with reference to the drawings described later.

By way of example, the radar device 100 may transmit a transmission pulse (TP) through a transmitter. The transmit pulse (TP) may hit the target and be reflected to become an echo pulse (EP). The radar device 100 may receive echo pulses (EP) from different locations through at least two receivers. The radar device 100 may acquire the azimuth angle (θ) of the target based on the time difference between the received echo pulses (EP).

In another example, the radar device 100 may emit transmission pulses TP at the same time through at least two transmitters. The radar device 100 may receive at least two echo pulses (EP) from which the transmission pulses (TP) are reflected and returned to the target through the receiver. The radar device 100 may acquire the azimuth angle (θ) of the target based on the time difference between the received echo pulses (EP).

The radar device 100 can acquire the azimuth angle (θ) of a target with high resolution through one transmitter and at least two receivers, or at least two transmitters and one receiver. A detailed description of the operation of the radar device 100 to acquire the azimuth angle (θ) of the target will be described with reference to the drawings described later.

FIG. 2 is a block diagram showing an example of the radar device of FIG. 1. Referring to FIG. 2, the radar device 100 may include a controller 110, a clock generator 120, a transmitter 130, a first receiver 140a, and a second receiver 140b.

The controller 110 may generate a variable delay control signal (DCS) and provide the variable delay control signal (DCS) to the clock generator 120 . The variable delay control signal (DCS) may be a signal corresponding to the delay time between the transmit clock (tCK) and the receive clock (dCK) generated by the clock generator 120. That is, the controller 110 can control the delay time between the transmit clock (tCK) and the receive clock (dCK) using the variable delay control signal (DCS).

The clock generator 120 may generate a transmission clock (tCK) and a reception clock (dCK) from the reference clock (rCK). The clock generator 120 may generate the transmission clock (tCK) by delaying the reference clock (rCK) by a certain time. The clock generator 120 may generate the reception clock (dCK) by delaying the reference clock (rCK) so that the reception clock (dCK) is delayed from the transmission clock (tCK) by the delay time corresponding to the variable delay control signal (DCS). there is. The clock generator 120 may provide a transmission clock (tCK) to the transmitter 130 and a reception clock (dCK) to the first receiver 140a and the second receiver 140b.

The transmitter 130 may radiate a transmission pulse (TP) through the transmission antenna 131 in response to the transmission clock (tCK). For example, the transmitter 130 may emit a transmission pulse (TP) at each rising edge of the transmission clock (tCK).

The transmitter 130 may generate a transmission pulse (TP) to be radiated. The transmitter 130 may generate transmission pulses (TP) having various center frequencies and bandwidths. To change the center frequency and bandwidth of the transmission pulse TP, the transmitter 130 may include an oscillator. The oscillator may generate a transmission pulse (TP) having a specific center frequency and a specific bandwidth according to a control signal provided from the controller 110. Accordingly, when the type of target to be detected changes or the situation in which the radar device 100 is applied changes, the radar device 100 can change the center frequency and bandwidth. For example, when detecting a target by penetrating a wall, the center frequency of the transmission pulse (TP) can be set low.

When the radiated transmission pulse (TP) is reflected to the target, the echo pulse (EP) may be received at various locations. As shown in FIG. 2, the first echo pulse EP1 may be received at the location of the first receiver 140a, and the second echo pulse EP2 may be received at the location of the second receiver 140b. there is. The time at which each of the first echo pulse EP1 and the second echo pulse EP2 are received may vary depending on the positions of the first receiver 140a and the second receiver 140b. For example, when the first receiver 140a is closer to the target than the second receiver 140b, the first echo pulse EP1 may be received before the second echo pulse EP2.

Hereinafter, for convenience of explanation, it is assumed that the echo pulse (EP) received by the first receiver (140a) is the first echo pulse (EP1), and the echo pulse (EP) received by the second receiver (140b) is assumed to be Assume it is the second echo pulse (EP2).

The first receiver 140a may receive a signal input through the first receiving antenna 141. The first receiver 140a may generate a first restored signal RS1 corresponding to the received signal value in response to the received clock dCK. For example, the first receiver 140a may generate the first recovery signal RS1 at the rising edge of the reception clock dCK. That is, the first receiver 140a may generate the first restored signal RS1 corresponding to the signal value received at a specific time in response to the reception clock dCK.

For example, if the first echo pulse EP1 is not received at the rising edge of the reception clock dCK (e.g., before the first echo pulse EP1 reaches the first reception antenna 141), (or when the first echo pulse (EP1) reaches the receiving antenna 141 and a time corresponding to the width of the first echo pulse (EP1) passes), the first receiver (140a) receives the first echo pulse (EP1) ) Instead, the first restored signal RS1 corresponding to the noise signal value may be generated. When the first echo pulse EP1 is received at the rising edge of the reception clock dCK (for example, when a specific value among the changing values of the first echo pulse EP1 is received), the first receiver 140a ) may generate a first recovery signal (RS1) corresponding to a specific value of the first echo pulse (EP1).

The second receiver 140b may receive a signal input through the second receiving antenna 142. The second receiver 140b may generate a second restored signal RS2 corresponding to the received signal value in response to the received clock dCK. For example, the second receiver 140b may generate the second recovery signal RS2 at the rising edge of the reception clock dCK. That is, the second receiver 140b may generate the second restored signal RS2 corresponding to the signal value received at a specific time in response to the reception clock dCK.

For example, if the second echo pulse EP2 is not received at the rising edge of the reception clock dCK (e.g., before the second echo pulse EP2 reaches the second reception antenna 142) or when the second echo pulse (EP2) reaches the receiving antenna 142 and a time corresponding to the width of the second echo pulse (EP2) elapses), the second receiver 140b receives the second echo pulse (EP2) Instead, a second restored signal RS2 corresponding to the noise signal value may be generated. When the second echo pulse EP2 is received at the rising edge of the reception clock dCK (for example, when a specific value among the changing values of the second echo pulse EP2 is received), the second receiver 140b ) may generate a second restoration signal (RS2) corresponding to a specific value of the second echo pulse (EP2).

Since the positions of the first receiver 140a and the second receiver 140b are different, the arrival times of the first echo pulse EP1 and the second echo pulse EP2 may be different. Accordingly, the first and second restored signals RS1 and RS2 generated from the first and second receivers 140a and 140b in response to the same reception clock dCK having a rising edge at the same time are different from each other. You can. For example, in response to the same reception clock (dCK), the first receiver (140a) generates a first recovery signal (RS1) corresponding to the noise signal value, and the second receiver (140b) generates a second echo pulse (EP2) ) can generate a second restored signal (RS2) corresponding to a specific value of ). Alternatively, in response to the same reception clock (dCK), the first receiver (140a) generates a first recovery signal (RS1) corresponding to the first value of the first echo pulse (EP1), and the second receiver (140b) A second recovery signal RS2 corresponding to the second value of the second echo pulse EP2 may be generated.

As shown in FIG. 2, the receiving antennas 141 and 142 may be located in a straight line with the transmitting antenna 131. The transmitting antenna 131 may be located in the center, and the receiving antennas 141 and 142 may be arranged to the left and right with respect to the transmitting antenna 131. However, the present invention is not limited to this, and the receiving antennas 141 and 142 and the transmitting antenna 131 may be placed in various locations. The distance between the receiving antennas 141 and 142 may be various values independent of the wavelength of the center frequency of the transmission pulse TP.

The radar device 100 according to an embodiment of the present invention may radiate a transmission pulse (TP) using a transmission clock and then, after a time delay, generate one restored signal at the receiver using a reception clock. That is, the radar device 100 can generate one restored signal from a pair of transmission clocks and reception clocks. The radar device 100 may use a number of restored signals to obtain information such as the distance and azimuth of the target.

For example, assume that the target is located at 3 m (pulse round-trip time 20 nsec) and the transmission pulse width of the radar device 100 is 1 nsec. The radar device 100 emits a transmission pulse (TP) with a pulse width of 1 nsec based on a transmission clock. When using a reception clock with a delay smaller than 20 nsec, the time to hit the target and return, the radar device 100 will receive a noise signal unrelated to the echo pulse (EP). If a reception clock with a delay of 20 nsec is used compared to the transmission clock, the radar device 100 will be able to restore the beginning of the echo pulse (EP) (i.e., restoration corresponding to the beginning of the echo pulse (EP) signal can be generated). When the following pair of transmission and reception clocks is generated, it is assumed that the radar device 100 generates transmission and reception clocks with a time delay of 20.01 nsec. Accordingly, the radar device 100 will restore the portion delayed by 0.01 nsec from the beginning of the echo pulse (EP) (that is, the restoration signal corresponding to the portion delayed by 0.01 nsec from the beginning of the echo pulse (EP) can be created). Thereafter, the radar device 100 may sequentially generate pairs of transmission and reception clocks with delay times of 20.02 nsec and 20.03 nsec. If the width of the echo pulse (EP) caused by the transmission pulse (TP) having a width of 1 nsec is 1 nsec, the entire echo pulse (EP) will be restored from 100 pairs of transmission and reception clocks. After the entire echo pulse (EP) is restored, if a reception clock with a delay of 21 nsec or more is used, the radar device 100 will restore a noise signal unrelated to the echo pulse (EP)

As described above, the transmission pulse TP emitted according to the transmission clock tCK may be reflected from the target and received by the first receiver 140a and the second receiver 140b. In this case, the first restoration signal (RS1) or the second restoration signal corresponding to the first echo pulse (EP1) or the second echo pulse (EP2) depending on the delay time between the transmission clock (tCK) and the reception clock (dCK). (RS2) can be generated. That is, if the delay time between the transmit clock (tCK) and the receive clock (dCK) is substantially the same as the time for the transmit pulse (TP) to reach the target, reflect from the target, and reach the receive antenna, the receiver ) can begin to generate a restoration signal corresponding to .

The controller 110 may receive the first restored signal RS1 from the first receiver 140a and the second restored signal RS2 from the second receiver 140b. The controller 110 may determine whether the first restoration signal RS1 or the second restoration signal RS2 has a value corresponding to the echo pulse EP. When the first recovery signal (RS1) or the second recovery signal (RS2) is a value corresponding to the echo pulse (EP), the controller 110 sets the value corresponding to the first recovery signal (RS1) or the second recovery signal (RS2) The distance (R) of the target can be obtained based on the delay time between the transmit clock (tCK) and the receive clock (dCK). For example, when the first recovery signal RS1 is greater than or equal to the threshold, the controller 110 may determine that the first recovery signal RS1 is a value corresponding to the echo pulse EP. In this case, the controller 110 may use a method of removing the background noise of the first restored signal RS1. The controller 110 may obtain the distance (R) of the target based on the delay time between the transmission clock (tCK) and the reception clock (dCK) corresponding to the first recovery signal (RS1).

The controller 110 determines the azimuth of the target based on the difference in reception time between the first recovery signal RS1 corresponding to the first echo pulse EP1 and the second recovery signal RS2 corresponding to the second echo pulse EP2. (θ) can be obtained. For example, the first recovery signal RS1 corresponding to the first echo pulse EP1 may be received, and the second recovery signal RS2 corresponding to the second echo pulse EP2 may be received. In this case, the controller 110 determines the first delay time between the transmission clock (tCK) and the reception clock (dCK) corresponding to the first recovery signal (RS1) and the transmission clock (tCK) corresponding to the second recovery signal (RS2). ) and the reception clock (dCK) can be obtained based on the second delay time between the azimuth angle (θ) of the target.

Alternatively, the controller 110 may obtain the distance (R) of the target from each of the first and second restoration signals (RS1) and second restoration signals (RS2) restored during one cycle. The controller 110 may obtain the azimuth angle (θ) of the target based on the difference in the distance (R) of the target obtained from each of the restoration signals RS1 and RS2.

Alternatively, the controller 110 determines the distance (R) of the target to the first receiver 140a and the second receiver 140b using the sum signal and difference signal of the restored signals RS1 and RS2 restored during one cycle. The difference in the distance (R) of the target can be obtained. The controller 110 may obtain the azimuth angle (θ) of the target based on the difference in distance.

The variable delay control signal (DCS) can change continuously over time. The variable delay control signal (DCS) can be continuously varied between a preset minimum value and a preset maximum value. The preset minimum value may correspond to the minimum delay time between the transmit clock (tCK) and the receive clock (dCK), and the preset maximum value may correspond to the maximum delay time between the transmit clock (tCK) and the receive clock (dCK). The delay time between the transmit clock (tCK) and the receive clock (dCK) may correspond to the detection distance of the target. Accordingly, the preset minimum value and the preset maximum value may indicate the detection distance section of the radar device 100. That is, the controller 110 can continuously change the detection distance of the target using the variable delay control signal (DCS). Accordingly, the clock generator 120 can generate a reception clock (dCK) whose delay time continuously changes.

The controller 110 may generate a variable delay control signal (DCS) that repeats according to a predetermined period. The controller 110 may output a control period signal (CPS) synchronized to a predetermined period in order to provide period information of the variable delay control signal (DCS) to the outside.

Hereinafter, the operation of the radar device 100 will be described in detail with reference to FIGS. 3 to 6.

3A and 3B show examples of variable delay control signals generated from the controller of FIG. 2. The horizontal axis of FIGS. 3A and 3B represents time, and the vertical axis represents the value of the variable delay control signal (DCS). For example, the variable delay control signal (DCS) may be a voltage or current value corresponding to the delay time between the transmit clock (tCK) and the receive clock (dCK).

Referring to FIG. 3A, the variable delay control signal (DCS) may continuously change between a minimum value (min) and a maximum value (max). The variable delay control signal (DCS), which has a minimum value (min) at time t0, may increase linearly with time and have a maximum value (max) at time t4. The variable delay control signal (DCS) may repeatedly have a minimum value (min) and a maximum value (max) according to a predetermined period (PE). That is, as shown in FIG. 3A, the variable delay control signal (DCS) may be a signal in the form of a sawtooth wave.

As the variable delay control signal (DCS) increases from the minimum value (min) to the maximum value (max), the delay time between the transmit clock (tCK) and the receive clock (dCK) may increase. Accordingly, the time interval of the rising edge of the receiving clock (dCK) may increase based on the rising edge of the transmitting clock (tCK), and the detection distance of the radar device 100 may change from the minimum value to the maximum value. When the target is located between the minimum and maximum values of the detection distance, the radar device 100 may detect the target based on a variable delay control signal (DCS) of one period (PE).

As shown in FIG. 3A, the variable delay control signal value dcs1 at time t1 is clock delay (hereinafter used with the same meaning as the delay time between the transmit clock (tCK) and the receive clock (dCK)) ( cd1), the variable delay control signal value (dcs2) at time t2 corresponds to the clock delay (cd2), and the variable delay control signal value (dcs3) at time t3 corresponds to the clock delay (cd3). You can.

For example, if the target is located further than the detection distance corresponding to the clock delay (cd1), the echo pulse (EP) at time t1 will not be detected based on the received clock (dCK) with the clock delay (cd1). It may not be possible. That is, the first receiver 140a of FIG. 2 may not be able to generate the first recovery signal RS1 corresponding to the first echo pulse EP1 based on the received clock dCK having the clock delay cd1. .

For example, if the target is located at a detection distance corresponding to the clock delay (cd2), the echo pulse (EP) at time t2 can be detected based on the received clock (dCK) with the clock delay (cd2). there is. That is, the first receiver 140a of FIG. 2 may generate the first recovery signal RS1 corresponding to the first echo pulse EP1 based on the received clock dCK having the clock delay cd2.

Although FIG. 3A shows an example of a variable delay control signal (DCS) linearly increasing from a minimum value (min) to a maximum value (max), the present invention is not limited thereto. For example, the controller 110 may generate a variable delay control signal (DCS) that linearly decreases from a maximum value (max) to a minimum value (min). In this way, when the variable delay control signal (DCS) changes linearly, the radar device 100 can detect a target with the same resolution from the minimum detection distance to the maximum detection distance.

Referring to FIG. 3B, the variable delay control signal (DCS) may continuously change between a minimum value (min) and a maximum value (max). The variable delay control signal (DCS) may increase non-linearly with time between the minimum value (min) and the maximum value (max) during one period (PE). The variable delay control signal (DCS) may increase rapidly in the area (A1) around the minimum value (min), and may increase gently in the area (A2) around the maximum value (max).

The controller 110 may generate the variable delay control signal (DCS) shown in FIG. 3B as well as various types of non-linearly changing variable delay control signals (DCS). For example, the controller 110 may generate a variable delay control signal (DCS) that increases gently in area A1 and increases rapidly in area A2. Alternatively, the controller 110 may generate a variable delay control signal (DCS) that non-linearly decreases from the maximum value (max) to the minimum value (min). In this way, when the variable delay control signal (DCS) changes non-linearly, the radar device 100 detects relatively more precisely (i.e., at a detection distance corresponding to an area where the slope of the variable delay control signal (DCS) is gentle. (with higher resolution) can detect targets.

Hereinafter, for convenience of explanation, the operation of the clock generator 120, the transmitter 130, and the first and second receivers 140a and 140b of FIG. 2 based on the variable delay control signal (DCS) of FIG. 3A. Explain them in detail.

FIG. 4 is a diagram showing examples of clocks and pulses generated according to the variable delay control signal of FIG. 3A. Specifically, the clocks (tCK, dCK) and pulses (TP, EP1, EP2) shown in FIG. 4 are variable delay control signals (t1, t2, t3) at times (t1, t2, t3), as shown in FIG. 3A. DCS). The horizontal axis in Figure 4 represents time. For convenience of explanation, the intervals between times t1, t2, and t3 are shown wide, but the present invention is not limited thereto. For example, to obtain high resolution, the interval between times (t1, t2, t3) can be very small.

Referring to FIGS. 3A and 4 , the clock generator 120 may generate a transmission clock (tCK) having rising edges at times (t1, t2, and t3). The clock generator 120 may receive a variable delay control signal (DCS) having a variable delay control signal value (dcs1) at time t1. The clock generator 120 may generate a reception clock (dCK) delayed by the clock delay (cd1) based on the variable delay control signal value (dcs1). The clock generator 120 may receive a variable delay control signal (DCS) having a variable delay control signal value (dcs2) at time t2. The clock generator 120 may generate a reception clock (dCK) delayed by the clock delay (cd2) based on the variable delay control signal value (dcs2). The clock generator 120 may receive a variable delay control signal (DCS) having a variable delay control signal value (dcs3) at time t3. The clock generator 120 may generate a reception clock (dCK) delayed by the clock delay (cd3) based on the variable delay control signal value (dcs3). Accordingly, the reception clock dCK may have rising edges at times t1d, t2d, and t3d.

As shown in FIG. 4, as the variable delay control signal values dcs1, dcs2, and dcs3 increase, the clock delays (cd1, cd2, and cd3) may increase. Accordingly, the detection distance of the radar device 100 can be increased.

The transmitter 130 may emit a transmission pulse (TP) in response to the transmission clock (tCK). The transmitter 130 may emit a transmission pulse (TP) at each rising edge (t1, t2, and t3) of the transmission clock (tCK). When the transmission pulse TP is reflected by the target, the first echo pulse EP1 and the second echo pulse EP2 may be transmitted to the first receiver 140a and the second receiver 140b, respectively.

The first receiver 140a may generate the first restored signal RS1 from the received signal in response to the received clock dCK. As shown in FIG. 4, the first echo pulse EP1 may not be received at time t1d, and the first echo pulse EP1 may be received at times t2d and t3d. Accordingly, the first receiver 140a generates a value corresponding to the noise value ns11 as the first restored signal RS1 in response to the received clock dCK having a clock delay cd1 at time t1d. You can. The first receiver 140a generates a value corresponding to the first echo pulse value ep11 as the first recovery signal RS1 in response to the received clock dCK having a clock delay cd2 at time t2d. You can. The first receiver 140a generates a value corresponding to the first echo pulse value ep12 as the first recovery signal RS1 in response to the received clock dCK having a clock delay cd3 at time t3d. You can.

The second receiver 140b may generate a second restored signal RS2 from the received signal in response to the received clock dCK. As shown in FIG. 4, the second echo pulse EP2 may not be received at times t1d and t2d, and the second echo pulse EP2 may be received at time t3d. Accordingly, the second receiver 140b generates a value corresponding to the noise value ns21 as the second restored signal RS2 in response to the received clock dCK having a clock delay cd1 at time t1d. You can. The second receiver 140b may generate a value corresponding to the noise value ns22 as the second restored signal RS2 in response to the received clock dCK having a clock delay cd2 at time t2d. The second receiver 140b generates a value corresponding to the second echo pulse value ep21 as a second recovery signal RS2 in response to the received clock dCK having a clock delay cd3 at time t3d. You can.

The first receiver 140a and the second receiver 140b have different relative positions with respect to the target. Due to the resulting path difference, the reception times of the first echo pulse EP1 and the second echo pulse EP2 may vary. Accordingly, a time difference (e.g., phase difference) between the first restored signal RS1 generated in the first receiver 140a and the second restored signal RS2 generated in the second receiver 140b )) may occur.

As shown in FIG. 4, the first receiver 140a may restore the first echo pulse EP1 in response to the reception clock dCK having various clock delays. Likewise, the second receiver 140b may restore the second echo pulse EP2 in response to the reception clock dCK having various clock delays. That is, the first receiver 140a and the second receiver 140b can restore one value corresponding to a specific point in time of the echo pulse EP for each rising edge of the reception clock dCK.

FIG. 5 is a diagram showing examples of restoration signals received by the controller of FIG. 2 and a control period signal (CPS) output from the controller. Specifically, FIG. 5 shows the first restored signal RS1, the second restored signal RS2, and the control period signal CPS from time t0 to time t5 in FIG. 3A.

Referring to FIGS. 3A, 4, and 5, from time t0 to time t4 is one period (PE) of the first receiver 140a. During this period, a variable delay control signal (DCS) is generated, and the first receiver 140a can restore the first echo pulse (EP1) using the reception clock (dCK). For example, among the first restoration signals RS1, the first restoration signal value rs11 at time t2d corresponds to the first echo pulse value ep11. Likewise, the first restoration signal value rs12 at time t3d may correspond to the first echo pulse value ep12.

In the same manner as above, the first receiver 140a can restore the first echo pulse EP1 during one period PE from time t4 to time t5. Accordingly, the controller 110 may receive the values of the first restored signal RS1 of FIG. 5 from the first receiver 140a during one period from time t0 to time t5.

The controller 110 may determine a section corresponding to the first echo pulse EP1 among the first recovery signal RS1. For example, since the size of the noise signal is generally smaller than the size of the echo pulse (EP), the controller 110 sets the values of the first restoration signal (RS1) that are greater than or equal to a threshold indicating a specific size to the first echo pulse (EP1). ) can be determined to correspond to. For example, as shown in FIG. 5, the controller 110 provides a first restored signal value (rs11) received at time t2d and a first restored signal value (rs13) received at time t4d. It can be determined by the value corresponding to 1 echo pulse (EP1).

The controller 110 may obtain the distance (R) of the target based on the first restoration signal value (rs11) during one period (PE) from time t0 to time t4. The controller 110 may obtain the distance (R) of the target based on the first restoration signal value (rs13) during one period (PE) from time t4 to time t5. For example, the controller 110 may obtain the distance (R) of the target from time t0 to time t4 using the clock delay (cd2) corresponding to the first recovery signal value (rs11). . For example, the controller 110 may obtain the time from the time corresponding to the minimum detection distance of one period (PE) to the time of restoration of the first restored signal value rs11. The controller 110 may obtain the distance (R) of the target using the ratio of the acquired time to one period (PE) value.

Alternatively, the controller 110 may obtain the distance (R) of the target from the reception time of each of the first and second restored signals (RS1) and second restored signals (RS2) restored during one cycle. Hereinafter, the operation of the controller 110 to obtain the distance R of the target will be described in detail with reference to FIG. 5.

Figure 5 shows restored signals (RS1, RS2) consisting of values restored from multiple pairs of transmit and receive clocks. Accordingly, these pulses are shown with the period (PE) of the variable delay control signal being much longer than the period of the transmission pulse (TP) and echo pulse (EP). The variable delay control signal (DCS) increases linearly between the minimum and maximum delay values. That is, the radar device 100 linearly detects the detection distance corresponding to the minimum value of the delay and the detection distance corresponding to the maximum value of the delay during the period (PE) of the variable delay control signal. A specific time of the period (PE) of the variable delay control signal may correspond to a specific detection distance between the minimum and maximum detection distances. From the restored signal, the radar device 100 can specify the location of the echo pulse (EP). As an example of a method of specifying the position of the echo pulse (EP), the controller 110 may specify the starting point of the restoration signal value section that is greater than the threshold as the position of the echo pulse (EP). The location of the specified echo pulse (EP) corresponds to a specific location in the period (PE) section of the variable delay control signal. Accordingly, the echo pulse (EP) may correspond to a specific detection distance between the minimum and maximum detection distances, and the radar device 100 may determine the location (detection distance) of the target.

As another example of a method of specifying the location of the echo pulse (EP), the controller 110 detects the envelope of the echo pulse (EP), obtains the range in which the envelope exceeds the threshold, and sets the center of the range to the echo pulse (EP). ) can be specified by the location. Similar to what was described above, the location of the target can be obtained from the location of the echo pulse (EP).

As another example of a method of specifying the location of the echo pulse (EP), the controller 110 may square the restored signal, convert it into an energy signal, and then apply a threshold to the converted signal. Alternatively, the controller 110 may detect the envelope of the converted signal, determine the range in which the envelope exceeds the threshold, and specify the center of the range as the location of the echo pulse (EP).

From time t0 to time t4, the second receiver 140b generates a second echo pulse EP2 based on the reception clock dCK generated according to the variable delay control signal DCS for one period PE. can be restored. For example, the second restored signal value rs21 at time t3d among the second restored signal RS2 may correspond to the second echo pulse value ep21.

Likewise, from time t4 to time t5, the second receiver 140b may restore the second echo pulse EP2 during one period PE. Accordingly, the controller 110 may receive the second restored signal RS2 of FIG. 5 from the second receiver 140b from time t0 to time t5.

The controller 110 may determine a value corresponding to the second echo pulse EP2 among the second recovery signals RS2. For example, as shown in FIG. 5, the controller 110 provides a second restored signal value (rs21) received at time t3d and a second restored signal value (rs22) received at time t5d. It can be determined that it corresponds to 2 echo pulse (EP2).

The controller 110 may obtain the distance (R) of the target based on the second restoration signal value (rs21) during one period (PE) from time t0 to time t4. The controller 110 may obtain the distance (R) to the target based on the second recovery signal value (rs22) during one period (PE) from time t4 to time t5. For example, the controller 110 may obtain the distance (R) of the target using the clock delay (cd3) corresponding to the second restoration signal value (rs21). Alternatively, the controller 110 may obtain the distance R of the target from the reception time of each of the restored signals RS1 and RS2 restored during one period PE.

As described above, in order to obtain the distance (R) of the target during one period (PE) from time t0 to time t4, the controller 110 uses the first recovery signal value rs11 and the second recovery signal value rs11. At least one of the signal values (rs21) can be used. Since the clock delay (cd2) corresponding to the first restored signal value (rs11) is smaller than the clock delay (cd3) corresponding to the second restored signal value (rs21), the obtained based on the first restored signal value (rs11) The distance (R) obtained based on the distance (R) and the second restored signal value (rs21) may be slightly different. If the target location is close and the distance between the receivers is long, the obtained distance (R) is There may be a bigger difference. Accordingly, the distance (R) of the target can be determined by comparing distance values of the target estimated from signals restored by a plurality of receivers.

For example, when obtaining the distance (R) of the target using both the first restoration signal value (rs11) and the second restoration signal value (rs21), the controller 110 sets the clock delay (cd2) and the clock delay ( The distance (R) of the target can be obtained based on the average value of cd3). Alternatively, the controller 110 operates from a time corresponding to the minimum detection distance of one period (PE) to a first time until the restoration of the first restored signal value rs11 and a restoration time of the second restored signal value rs21. The second time can be obtained. The controller 110 may obtain the distance (R) of the target using the ratio of the obtained average value of the first time and the second time to the value of one period (PE).

The controller 110 may acquire the azimuth angle θ of the target based on the time difference between the first echo pulse EP1 and the second echo pulse EP2. For example, as shown in FIG. 5, the controller 110 generates a first recovery signal value corresponding to the first echo pulse EP1 during one period PE from time t0 to time t4. Based on the reception time difference (sd1) between the time (t2d) at which rs11) was received and the time (t3d) at which the second restoration signal value (rs21) corresponding to the second echo pulse (EP2) was received, the azimuth angle (θ) of the target ) can be obtained. The reception time difference (sd1) can be calculated from the clock delay (cd2) and clock delay (cd3). In this case, the position indicated by the first restored signal value rs11 in the first restored signal RS1 and the position indicated by the second restored signal value rs21 in the second restored signal RS2 may correspond. That is, the first restored signal value (rs11) and the second restored signal value (rs21) may be the same.

As described above, the controller 110 can specify the location of the echo pulse EP from the restoration signals RS1 and RS2 using various methods. For example, as shown in FIG. 5, the controller 110 may determine whether the restored signal value at a specific point in time is greater than or equal to a specific threshold and determine the location of the echo pulse EP. If the relative positions of the receivers with respect to the target are arranged differently, a time difference may occur between echo pulses (EPs) recovered from each receiver. This time difference may be caused by a path difference relative to the target. The azimuth can be calculated using this path difference. The value of the time difference due to the path difference between the restored signals RS1 and RS2 during one period (PE) from time t0 to time t4 may be “sd1”. The reception time difference (sd1) due to the path difference can be converted to distance. The converted distance may correspond to the route difference. The controller 110 may calculate the azimuth angle θ from the path difference. Alternatively, the controller 110 may calculate the azimuth angle θ from the time corresponding to the minimum detection distance of one period PE to the time of restoration of the first recovery signal RS1. The first time may be obtained, and the distance (R) of the first target may be obtained using the ratio of the obtained first time to one period (PE) value. The controller 110 obtains a second time from a time corresponding to the minimum detection distance of one period (PE) to the time of restoration of the second recovery signal RS2, and obtains a second time for the value of one period (PE). The distance (R) of the second target can be obtained using the time ratio. The controller 110 may obtain a distance corresponding to the reception time difference (sd2) from the difference between the distance (R) of the first target and the distance (R) of the second target. The controller 110 may calculate the azimuth angle θ from the distance corresponding to the reception time difference sd1.

The controller 110 receives the first echo pulse (EP1) and the first restoration signal value (rs13) corresponding to the first echo pulse (EP1) during one period (PE) from time t4 to time t5 at the time t4d and the second The azimuth angle (θ) of the target may be obtained based on the reception time difference (sd2) between the time (t5d) at which the echo pulse (EP2) and the corresponding second restoration signal value (rs22) were received. The reception time difference (sd2) can be calculated from the clock delay (cd4) and clock delay (cd5).

The controller 110 can convert the reception time difference (sd2) into a distance. The converted distance may correspond to the route difference. The controller 110 may calculate the azimuth angle (θ) from the path difference.

Alternatively, the controller 110 acquires the first time from the time corresponding to the minimum detection distance of one period (PE) to the time of restoration of the first recovery signal (RS1), and obtains the obtained time for the value of one period (PE) The distance (R) of the first target can be obtained using the first time ratio. The controller 110 obtains a second time from a time corresponding to the minimum detection distance of one period (PE) to the time of restoration of the second recovery signal RS2, and obtains a second time for the value of one period (PE). The distance (R) of the second target can be obtained using the time ratio. The controller 110 may obtain a distance corresponding to the reception time difference (sd2) from the difference between the distance (R) of the first target and the distance (R) of the second target. The controller 110 may calculate the azimuth angle (θ) from the distance corresponding to the reception time difference (sd2).

The smaller the time difference between the first echo pulse (EP1) and the second echo pulse (EP2) received, the smaller the azimuth angle (θ) of the target may be. As shown in Figure 5, when the reception time difference (sd1) is smaller than the reception time difference (sd2), the azimuth angle (θ) of the target during one period (PE) from time t0 to time t4 is time It may be smaller than the azimuth angle (θ) of the target during one period (PE) from (t4) to time (t5).

The controller 110 may externally output a control period signal (CPS) synchronized to a predetermined period (PE). For example, as shown in FIG. 5, when the variable delay control signal (DCS) is at the minimum value (min) (i.e., time (t0)), the controller 110 outputs a control period signal (CPS) of a square wave. can do. Likewise, at the time t4 when the next period PE starts (i.e., when the variable delay control signal DCS is at the minimum value min), the controller 110 can output the control period signal CPS of a square wave. there is. When the control period signal (CPS) is output to the outside of the controller 110, various signal processors outside the controller 110 can analyze various information using the control period signal (CPS). For example, an external signal processor may use the control period signal (CPS) to calculate the distance (R) of the target from the restoration signal (RS).

Hereinafter, a method for obtaining the distance (R) of the target and the azimuth (θ) of the target will be described in detail with reference to FIG. 6.

FIG. 6 is a diagram showing how the controller of FIG. 2 acquires the distance and azimuth of the target. In general, the distance between the transmitting antenna 131 and the receiving antennas 141 and 142 is much smaller than the distance between the antennas 131, 141 and 142 and the target, so FIG. 6 is a diagram different from the actual distance. You can. Hereinafter, it is assumed that the distance between the transmitting antenna 131 and the receiving antennas 141 and 142 is much smaller than the distance between the antennas 131, 141 and 142 and the target.

Referring to FIG. 6, the distance (R) from the radar device 100 to the target can be assumed to be the distance (R) from the transmitting antenna 131 to the target. As described in FIG. 5, the controller 110 obtains the distance (R1) from the first receiving antenna 141 to the target based on the first echo pulse (EP1) received through the first receiving antenna 141. can do. The controller 110 may obtain the distance R2 from the second receiving antenna 142 to the target based on the second echo pulse EP2 received through the second receiving antenna 142. When the distance between the antennas 131, 141, and 142 and the target is much greater than the distance between the transmitting antenna 131 and the receiving antennas 141 and 142, the distance from the first receiving antenna 141 to the target ( Since the difference between R1) and the distance (R2) from the second receiving antenna 142 to the target is very small compared to the distance (R) of the target, the distance (R) of the target is divided into distance (R1), distance (R2), or It can be approximated by the average value of distance (R1) and distance (R2).

The first receiving antenna 141 may receive the first echo pulse EP1 through the first path P1. The second receiving antenna 142 may receive the second echo pulse EP2 through the second path P2. As shown in FIG. 6, when the azimuth angle (θ) of the target is not '0', a path difference (pad) may exist between the first path (P1) and the second path (P2). Due to the path difference (pad), the time at which the first echo pulse (EP1) and the second echo pulse (EP2) are received may be different.

The path difference (pad) may be a function of the azimuth angle (θ) of the target and the separation distance (rad) between the first and second receiving antennas 141 and 142. For example, if the distance between the antennas 131, 141, and 142 and the target is much greater than the distance between the transmitting antenna 131 and the receiving antennas 141 and 142, the path difference (pad) is as follows. It can be expressed as Equation 1.

As described in FIG. 5, the controller 110 can calculate the time difference between the first echo pulse (EP1) and the second echo pulse (EP2) and calculate the path difference (pad) from the reception time difference. You can. The controller 110 may obtain the azimuth angle (θ) using the separation distance (rad) and the path difference (pad) based on Equation 1 above.

As described above, the radar device 100 may generate the reception clock (dCK) based on the continuously changing variable delay control signal (DCS). Accordingly, the radar device 100 can precisely adjust the delay time between the transmission clock (tCK) and the reception clock (dCK). The radar device 100 can precisely analyze the delay relationship between the echo pulses EP1 and EP2 recovered from the reception clock dCK and acquire azimuth angle θ information of the target with high resolution. In addition, the radar device 100 may obtain the delay relationship between the distance (R) of the target and the echo pulses (EP1, EP2) from the reception time of the restored echo pulses (EP1, EP2) during one period (PE). You can.

Since the radar device 100 detects a target through a pulse and uses two receiving antennas 141 and 142, the separation distance (rad) between the two receiving antennas 141 and 142 can be freely determined. there is. For example, the separation distance (rad) may be determined to be more than half the wavelength of the center frequency of the transmission pulse (TP). When the separation distance (rad) increases, the path difference for a target located at the same azimuth angle (θ) may increase. Accordingly, the radar device 100 can analyze the increased path difference for the same azimuth angle (θ). That is, the resolution of the azimuth angle (θ) can be increased. As shown in Equation 1, if the separation distance (rad) increases, the path difference (pad) may increase for the same azimuth angle (θ).

FIG. 7 is a block diagram showing the clock generator of FIG. 2. Referring to FIG. 7 , the clock generator 120 may include a first delay element 121, a second delay element 122, a phase comparator 123, a filter 124, and an error amplifier 125.

The first delay element 121 may generate a transmission clock (tCK) by delaying the reference clock (rCK) based on the first delay control signal (DS1). The first delay control signal DS1 may be a signal corresponding to the delay time between the reference clock (rCK) and the transmission clock (tCK). The first delay control signal DS1 may be a specific preset value. Exemplarily, the first delay control signal DS1 may be provided from the controller 110. The transmission clock (tCK) output from the first delay element 121 may be provided to the transmitter 130 and the phase comparator 123.

The second delay element 122 may generate the reception clock (dCK) by delaying the reference clock (rCK) based on the second delay control signal (DS2). The second delay control signal DS2 may be a signal corresponding to the delay time between the reference clock (rCK) and the received clock (dCK). The value of the second delay control signal DS2 may change depending on the variable delay control signal DCS. The second delay control signal DS2 may be provided from the error amplifier 125. The received clock dCK output from the second delay element 122 may be provided to the first and second receivers 140a and 140b and the phase comparator 123.

The phase comparator 123 may compare the phases of the transmit clock (tCK) and the receive clock (dCK) and output a phase comparison output signal (CR). As an example, the phase comparator 123 may output a square wave corresponding to the phase difference (i.e., clock delay) between the transmit clock (tCK) and the receive clock (dCK) as the phase comparison output signal (CR). In this case, the duty cycle of the square wave may be proportional to the phase difference.

The filter 124 may remove high frequency components included in the phase comparison output signal CR. For example, filter 124 may be a low pass filter. The filtered phase comparison output signal (FCR) output through the filter 124 may be provided to the error amplifier 125.

The error amplifier 125 may receive the filtered phase comparison output signal (FCR) and the variable delay control signal (DCS), and amplify the difference between the filtered phase comparison output signal (FCR) and the variable delay control signal (DCS). there is. For example, if the variable delay control signal (DCS) is greater than the filtered phase comparison output signal (FCR) (i.e., the delay time between the transmit clock (tCK) and the receive clock (dCK) is less than the desired delay time, The error amplifier 125 may output an increased second delay control signal DS2. Accordingly, the second delay element 122 that receives the second delay control signal DS2 may further increase the delay of the reference clock rCK to generate the received clock dCK. If the variable delay control signal (DCS) is less than the filtered phase comparison output signal (FCR) (i.e., the delay time between the transmit clock (tCK) and the receive clock (dCK) is greater than the desired delay time, the error amplifier (125) ) may output a reduced second delay control signal DS2. Accordingly, the second delay element 122 that receives the second delay control signal DS2 may further reduce the delay of the reference clock rCK to generate the received clock dCK.

As described above, the clock generator 120 may form a feedback path through which the output signal DS2 of the error amplifier 125 is input to the second delay element 122. Accordingly, the error between the delay time between the transmission clock (tCK) and the reception clock (dCK) and the desired delay time can be reduced. Additionally, the clock generator 120 may not include a compensation circuit for the first and second delay elements 121 and 122. Accordingly, a miniaturized radar device 100 can be implemented, and the radar device 100 can operate with low power.

FIG. 8 is a block diagram showing the receiver of FIG. 2. For convenience of explanation, FIG. 8 will be described based on the first receiver 140a. However, the present invention is not limited to this, and the second receiver 140b may be implemented in the same way as the first receiver 140a.

Referring to FIG. 8, the first receiver 140a may include a first receiving antenna 141, a low-noise amplifier 143, a sampler 144, a variable amplifier 145, and an analog-to-digital converter 146. The first receiving antenna 141 may receive the first echo pulse EP1 and transmit the received first echo pulse EP1 to the low noise amplifier 143.

The low-noise amplifier 143 may amplify the first echo pulse EP1. The amplified first echo pulse (AEP1) may be provided to a sampler (sampler) 144. The sampler 144 may sample the amplified first echo pulse AEP1 in response to the reception clock dCK. For example, the sampler 144 may sample the amplified first echo pulse AEP1 value at the rising edge of the reception clock dCK. The sampled signal SS may be provided to the variable amplifier 145.

The variable amplifier 145 may amplify the sampled signal SS. The amplified sampled signal (ASS) may be provided to analog-to-digital converter 146. The analog-to-digital converter 146 may generate the first restored signal RS1 by converting the amplified sampled signal ASS into a digital signal.

As described above, the first receiver 140a may sample the signal value received through the first reception antenna 141 in response to the reception clock dCK. That is, when the first echo pulse EP1 is received at the time the reception clock dCK is provided, the first receiver 140a samples a value corresponding to the first echo pulse EP1, and the sampled signal ( The first restored signal RS1 may be generated based on SS).

Figure 9 is a flowchart showing the operation of a radar device according to an embodiment of the present invention. Referring to FIGS. 2 and 9 , in step S101, the radar device 100 may generate a transmission clock (tCK) and a reception clock (dCK) based on the variable delay control signal (DCS). The variable delay control signal (DCS) may be a signal that changes continuously over time between a preset minimum value and a preset maximum value. The radar device 100 may generate a reception clock (dCK) delayed by a delay time corresponding to the variable delay control signal (DCS) rather than the transmission clock (tCK).

In step S102, the radar device 100 may emit a transmission pulse (TP) based on the transmission clock (tCK). In step S103, the radar device 100 may receive an echo pulse (EP) in which the transmission pulse (TP) is reflected from the target. The echo pulse (EP) received by the first receiving antenna 141 of the radar device 100 is the first echo pulse (EP1), and the echo pulse (EP) received by the second receiving antenna 142 is the second echo. It may be a pulse (EP2). That is, the radar device 100 may receive the first echo pulse EP1 through the first receiving antenna 141 and the second echo pulse EP2 through the second receiving antenna 142.

In step S104, the radar device 100 may generate first and second restored signals RS1 and RS2 based on the received clock dCK. The radar device 100 may generate a first recovery signal (RS1) corresponding to the first echo pulse (EP1) based on the reception clock (dCK), and a second recovery signal (RS1) corresponding to the second echo pulse (EP2). A signal (RS2) can be generated.

In step S105, the radar device 100 may acquire the distance (R) of the target and the azimuth (θ) of the target based on the first and second recovery signals (RS1 and RS2). The radar device 100 may obtain the distance R of the target based on the delay time between the transmission clock (tCK) and the reception clock (dCK) corresponding to at least one of the recovery signals RS1 and RS2. The radar device 100 may specify the location of the echo pulse (EP) in the recovery signal and obtain the distance (R) of the target from the specified location. The radar device 100 includes a separation distance between the first and second receiving antennas 141 and 142, a clock delay corresponding to the first recovered signal (RS1), and a clock corresponding to the second recovered signal (RS2). Based on the delay, the azimuth angle (θ) of the target can be obtained. The radar device 100 determines the distance (R) from the first receiving antenna 141 to the first target from the reception times of the restored signals RS1 and RS2 during one period (PE) and the second receiving antenna 142. ), the distance (R) to the second target can be obtained. The radar device 100 may acquire the azimuth angle (θ) based on the difference between the distance (R) to the first target and the distance (R) to the second target.

Figure 10 is a flowchart showing the operation of a radar device generating a transmission clock and a reception clock according to an embodiment of the present invention. Referring to FIGS. 2 and 10 , in step S111, the radar device 100 may receive a reference clock (rCK). In step S112, the radar device 100 may generate a transmission clock (tCK) by delaying the reference clock (rCK) based on the first delay control signal (DS1). In step S113, the radar device 100 may generate the reception clock (dCK) by delaying the reference clock (rCK) based on the second delay control signal (DS2).

In step S114, the radar device 100 may compare the phase of the transmission clock (tCK) and the phase of the reception clock (dCK) and output a phase comparison output signal (CR). In step S115, the radar device 100 may amplify the difference between the phase comparison output signal (CR) and the variable delay control signal (DCS) and output the second delay control signal (DS2). For example, the radar device 100 may remove high frequency components of the phase comparison output signal (CR) before amplifying the difference between the phase comparison output signal (CR) and the variable delay control signal (DCS). The radar device 100 may output a second delay control signal DS2 by amplifying the difference between the filtered phase comparison output signal and the variable delay control signal DCS.

FIG. 11 is a block diagram showing another embodiment of the radar device of FIG. 1. Referring to FIG. 11 , the radar device 200 may include a controller 210, a clock generator 220, a first transmitter 230a, a second transmitter 230b, and a receiver 240. The operations of the controller 210 and the clock generator 220 are similar to the operations of the controller 110 and the clock generator 120 of FIG. 2, and the operations of the first transmitter 230a and the second transmitter 230b are similar to those of FIG. 2. It is similar to the operation of the transmitter 130, and the operation of the receiver 240 may be similar to the operation of the first receiver 140a or the second receiver 140b. Accordingly, overlapping descriptions may be omitted. Below, the radar device 200 of FIG. 11 will be described focusing on differences from the radar device 100 of FIG. 2.

The controller 210 may generate a variable delay control signal (DCS) and provide the variable delay control signal (DCS) to the clock generator 220 . The clock generator 220 may generate a transmit clock (tCK) and a receive clock (dCK) from the reference clock (rCK). Based on the variable delay control signal (DCS), the clock generator 220 may generate a reception clock (dCK) that is delayed from the transmission clock (tCK) by a delay time corresponding to the variable delay control signal (DCS).

The first transmitter 230a may radiate the first transmission pulse TP1 through the first transmission antenna 231 in response to the transmission clock tCK. The second transmitter 230b may radiate a second transmission pulse TP2 through the second transmission antenna 232 in response to the transmission clock tCK. The first transmitter 230a and the second transmitter 230b may simultaneously emit the first transmission pulse TP1 and the second transmission pulse TP2.

The receiver 240 may receive echo pulses EP1 and EP2 input through the reception antenna 241. The receiver 240 may generate a restored signal (RS) corresponding to the received signal value in response to the received clock (dCK). The receiver 240 receives the first echo pulse (EP1), in which the first transmission pulse (TP1) is reflected and returned to the target, and the second echo pulse (EP2), in which the second transmission pulse (TP2) is reflected and returned to the target. can do. When the first echo pulse EP1 and the second echo pulse EP2 are received through one receiver 240, the first echo pulse EP1 and the second echo pulse EP2 may overlap. Accordingly, the echo pulse (SEP) received by the receiver 240 by the first echo pulse (EP1) and the second echo pulse (EP2) overlaps the first echo pulse (EP1) and the second echo pulse (EP2). It may be a pulse in the form of The receiver 240 may generate a restoration signal (RS) corresponding to the overlapped echo pulse (SEP) and provide it to the controller 210.

The waveform of the restoration signal RS may vary depending on the difference in reception times between the first echo pulse EP1 and the second echo pulse EP2. The controller 210 may analyze the waveform of the restoration signal (RS). The controller 210 may obtain the distance (R) of the target and the azimuth (θ) of the target based on the analyzed information. By way of example, the controller 210 may determine the restoration signal (RS) corresponding to the echo pulse (SEP). The controller 210 may obtain the distance (R) of the target based on the delay time between the transmission clock (tCK) and the reception clock (dCK) corresponding to the determined recovery signal (RS). Alternatively, the controller 210 may obtain the distance (R) of the target from the reception time of the restored signal (RS) during one period (PE).

As an example, the controller 210 may calculate the difference between the time at which the first echo pulse EP1 was received and the time at which the second echo pulse EP2 was received from the waveform of the restoration signal RS. The controller 210 may obtain the azimuth angle (θ) of the target based on the calculated reception time difference.

The controller 210 may output a control period signal (CPS) synchronized to a predetermined period in order to provide period information of the variable delay control signal (DCS) to the outside.

As described above, the radar device 200 can acquire the distance (R) and the azimuth (θ) of the target using two transmitters (230a, 230b) and one receiver (240). That is, when transmitting the transmission pulses TP1 and TP2 simultaneously from different locations, the radar device 200 can obtain the location information and speed information of the target through one receiver 240.

FIG. 12 is a diagram showing an example of a restored signal generated from the radar device of FIG. 11. Referring to FIGS. 11 and 12 , the receiver 240 may receive the first echo pulse EP1 and the second echo pulse EP2. Since the time for the first transmission pulse (TP1) and the second transmission pulse (TP2) to reach the target may vary depending on the location of the target, the time at which the first echo pulse (EP1) is received and the second echo pulse (EP2) The time at which it is received may vary. As shown in FIG. 12, the first echo pulse EP1 may be received earlier than the second echo pulse EP2 by the reception time difference sd.

As described in FIG. 11, the first echo pulse EP1 and the second echo pulse EP2 may overlap. The receiver 240 may generate a restoration signal (RS) from the overlapped echo pulse (SEP). The restoration signal (RS) may have a value corresponding to the overlapped echo pulse (SEP). That is, the waveform of the restoration signal RS may be substantially the same as the waveform of the superimposed echo pulse SEP. The waveform of the echo pulse (SEP) may vary depending on the difference in reception times between the first echo pulse (EP1) and the second echo pulse (EP2).

The controller 210 may analyze the waveform of the restoration signal (RS). The controller 210 may determine that the echo pulse SEP has been received when the magnitude of the specific value rs of the recovery signal RS is greater than or equal to the threshold. The controller 210 may obtain the distance (R) of the target based on the clock delay (cd) corresponding to a specific value (rs). Alternatively, the controller 210 may obtain the distance (R) of the target from the reception time of the restored signal (RS) during one period (PE).

The controller 210 may acquire the reception time difference (sd) between the first echo pulse (EP1) and the second echo pulse (EP2) by analyzing the waveform of the restoration signal (RS). The controller 210 may acquire the azimuth angle (θ) of the target based on the reception time difference (sd).

FIG. 13 is a diagram showing how the controller of FIG. 11 obtains the distance and azimuth of the target. Unlike shown in FIG. 13, the distance between the transmitting antennas 231 and 232 and the receiving antenna 241 may be much smaller than the distance between the antennas 231, 232 and 241 and the target. Hereinafter, it is assumed that the distance between the transmitting antennas 231 and 232 and the receiving antenna 241 is much smaller than the distance between the antennas 231, 232 and 241 and the target. The separation distance between the transmission antennas 231 and 232 may be arbitrarily set to a value greater than or equal to a half wavelength of the center frequency of the transmission pulses TP1 and TP2.

Referring to FIG. 13, the distance (R) from the radar device 200 to the target can be assumed to be the distance (R) from the receiving antenna 241 to the target. As described in FIG. 12, the controller 210 may obtain the distance (R) from the receiving antenna 241 to the target based on the overlapped echo pulse (SEP) received through the receiving antenna 241. If the separation distance between the transmitting antennas 231 and 232 is sufficient, the receiving antenna 241 can receive separated echo pulses (EP). In this case, as described above, the distance (R) and azimuth (θ) of the target can be obtained.

The first transmission antenna 231 may transmit the first transmission pulse TP1 through the first path P1. The second transmission antenna 232 may transmit the second transmission pulse TP2 through the second path P2. As shown in FIG. 13, when the azimuth angle (θ) of the target is not '0', a path difference (pad) may exist between the first path (P1) and the second path (P2). Due to the path difference (pad), the time for the first transmission pulse (TP1) and the second transmission pulse (TP2) to reach the target may be different. Accordingly, the time for the first echo pulse (EP1) according to the first transmission pulse (TP1) to reach the receiving antenna 241 and the time for the second echo pulse (EP2) according to the second transmission pulse (TP2) to reach the receiving antenna (241) 241) may vary. The receiving antenna 241 may receive overlapped echo pulses (SEP) having different shapes depending on the difference in reception times between the first echo pulse (EP1) and the second echo pulse (EP2).

The path difference (pad) may be a function of the azimuth angle (θ) of the target and the separation distance (tad) between the first and second transmission antennas 231 and 232. For example, if the distance between the antennas 231, 232, and 241 and the target is much greater than the distance between the transmit antennas 231 and 232 and the receive antenna 241, the path difference (pad) is calculated using the math below: It can be expressed as Equation 2.

As described in FIG. 12, the controller 210 can obtain the reception time difference between the first echo pulse (EP1) and the second echo pulse (EP2) and calculate the path difference (pad) from the reception time difference. there is. The controller 210 may obtain the azimuth angle (θ) using the separation distance (tad) and the path difference (pad) based on Equation 2 above.

As described above, the radar device 200 may generate the reception clock (dCK) based on the continuously changing variable delay control signal (DCS). Accordingly, the radar device 200 can precisely adjust the delay time between the transmission clock (tCK) and the reception clock (dCK). The radar device 200 restores the overlapped echo pulse (SEP) based on the received clock (dCK) and precisely determines the delay relationship between the first and second echo pulses (EP1 and EP2) from the restored signal (RS). It can be analyzed. Accordingly, the radar device 200 can acquire azimuth angle (θ) information of the target with high resolution.

As described above, the radar device according to embodiments of the present invention may include at least two receiving antennas or at least two transmitting antennas. For convenience of explanation, two receiving antennas or two transmitting antennas are shown as being arranged in a vertical direction, but the present invention is not limited thereto, and the receiving and transmitting antennas of the present invention may be arranged in various directions and at various intervals. You can.

Components of the radar device according to the embodiments of the present invention described above may be implemented in the form of software, hardware, or a combination thereof. By way of example, software may be machine code, firmware, embedded code, and application software. For example, hardware may include an electrical circuit, an electronic circuit, a processor, a computer, an integrated circuit, integrated circuit cores, a pressure sensor, an inertial sensor, a Micro Electro Mechanical System (MEMS), a passive component, or a combination thereof. You can.

The above-described details are specific embodiments for carrying out the present invention. The present invention will include not only the above-described embodiments, but also embodiments that can be simply changed or easily changed in design. In addition, the present invention will also include technologies that can be easily modified and implemented using the embodiments. Therefore, the scope of the present invention should not be limited to the above-described embodiments, but should be determined by the claims and equivalents of the present invention as well as the claims described later.

100, 200: Radar device
110, 210: controller
120, 220: clock generator
130, 230a, 230b: Transmitter
131, 231, 232: Transmitting antenna
140a, 140b, 240: Receiver
141, 142, 241: Receiving antenna

Claims (19)

a controller configured to generate a variable delay control signal whose value varies with time;
a clock generator configured to generate a reception clock delayed from the transmission clock by a delay time that varies according to a transmission clock and the variable delay control signal;
a transmitter configured to radiate a transmission pulse through a transmission antenna based on the transmission clock;
a first receiver configured to receive a first echo pulse in which the transmission pulse is reflected from a target through a first reception antenna and generate a first recovery signal corresponding to the first echo pulse based on the reception clock; and
It includes a second receiver configured to receive a second echo pulse in which the transmission pulse is reflected from the target through a second reception antenna and generate a second recovery signal corresponding to the second echo pulse based on the reception clock. do,
The controller is configured to at least one of a first delay time between the transmission clock and the reception clock corresponding to the first recovery signal and a second delay time between the transmission clock and the reception clock corresponding to the second recovery signal. further configured to obtain a distance of the target based on
The clock generator is,
a first delay element configured to generate the transmission clock by delaying a reference clock based on a first delay control signal;
a second delay element configured to generate the received clock by delaying the reference clock based on a second delay control signal;
a phase comparator configured to compare the phase of the transmit clock and the phase of the receive clock to output a phase comparison output signal; and
A radar device comprising an error amplifier configured to amplify a difference between the phase comparison output signal and the variable delay control signal to output the second delay control signal. According to claim 1,
The controller is further configured to acquire the azimuth of the target based on the separation distance between the first receiving antenna and the second receiving antenna, the first delay time, and the second delay time. According to claim 2,
A radar device wherein the separation distance is more than half the wavelength of the center frequency of the transmission pulse. According to claim 1,
A radar device wherein the variable delay control signal continuously changes between a preset minimum value and a preset maximum value. delete According to claim 1,
Each of the first receiver and the second receiver,
a low-noise amplifier configured to amplify a received echo pulse of the first echo pulse and the second echo pulse;
a sampler configured to sample the amplified echo pulse in response to the reception clock and output a sampled signal;
a variable amplifier configured to amplify the sampled signal; and
A radar device comprising an analog-to-digital converter configured to convert the amplified sampled signal into a digital signal and output a corresponding restored signal among the first restored signal and the second restored signal. According to claim 1,
A radar device wherein the transmitter includes an oscillator configured to change the center frequency and bandwidth of the transmitted pulse. According to claim 1,
The variable delay control signal is generated according to a predetermined period,
The radar device is further configured to output a control period signal synchronized to the predetermined period. a controller configured to generate a variable delay control signal whose value varies with time;
a clock generator configured to generate a reception clock delayed from the transmission clock by a delay time that varies according to a transmission clock and the variable delay control signal;
a first transmitter configured to radiate a first transmission pulse through a first transmission antenna based on the transmission clock;
a second transmitter configured to radiate a second transmission pulse through a second transmission antenna based on the transmission clock; and
Receive at least one echo pulse in which the first transmission pulse and the second transmission pulse are reflected from the target through a receiving antenna, and generate at least one recovery signal corresponding to the at least one echo pulse based on the reception clock. a receiver configured to generate,
the controller is further configured to obtain the distance of the target based on a delay time between the transmit clock and the receive clock corresponding to the at least one recovery signal,
The clock generator is,
a first delay element configured to generate the transmission clock by delaying a reference clock based on a first delay control signal;
a second delay element configured to generate the received clock by delaying the reference clock based on a second delay control signal;
a phase comparator configured to compare the phase of the transmit clock and the phase of the receive clock to output a phase comparison output signal; and
A radar device comprising an error amplifier configured to amplify a difference between the phase comparison output signal and the variable delay control signal to output the second delay control signal. According to clause 9,
The controller is further configured to acquire the azimuth of the target based on information analyzed from the waveform of the at least one reconstructed signal and a separation distance between the first and second transmission antennas. According to clause 9,
A radar device wherein the variable delay control signal continuously changes between a preset minimum value and a preset maximum value. delete According to clause 9,
The receiver is,
a low-noise amplifier configured to amplify the received echo pulse;
a sampler configured to sample the amplified echo pulse in response to the reception clock and output a sampled signal;
a variable amplifier configured to amplify the sampled signal; and
A radar device comprising an analog-to-digital converter configured to convert the amplified sampled signal into a digital signal and output the restored signal. a controller configured to generate a variable delay control signal whose value varies with time;
a clock generator configured to generate a reception clock delayed from the transmission clock by a delay time that varies according to a transmission clock and the variable delay control signal;
a transmitter configured to radiate a transmission pulse through a transmission antenna based on the transmission clock;
a first receiver configured to receive a first echo pulse in which the transmission pulse is reflected from a target through a first reception antenna and generate a first recovery signal corresponding to the first echo pulse based on the reception clock; and
It includes a second receiver configured to receive a second echo pulse in which the transmission pulse is reflected from the target through a second reception antenna and generate a second recovery signal corresponding to the second echo pulse based on the reception clock. do,
The controller determines a first time ratio from the minimum distance detection time for the cycle of the variable delay control signal to the restoration time of the first restored signal and the minimum distance detection time for the cycle of the variable delay control signal. 2 further configured to obtain the distance of the target based on at least one of a second time ratio to the recovery point of the recovery signal,
The clock generator is,
a first delay element configured to generate the transmission clock by delaying a reference clock based on a first delay control signal;
a second delay element configured to generate the received clock by delaying the reference clock based on a second delay control signal;
a phase comparator configured to compare the phase of the transmit clock and the phase of the receive clock to output a phase comparison output signal; and
A radar device comprising an error amplifier configured to amplify a difference between the phase comparison output signal and the variable delay control signal to output the second delay control signal. According to claim 14,
The controller is further configured to acquire the azimuth of the target based on the difference between the distance of the first target obtained using the first time ratio and the distance of the second target obtained using the second time ratio. . delete According to claim 14,
Each of the first receiver and the second receiver,
a low-noise amplifier configured to amplify a received echo pulse of the first echo pulse and the second echo pulse;
a sampler configured to sample the amplified echo pulse in response to the reception clock and output a sampled signal;
a variable amplifier configured to amplify the sampled signal; and
A radar device comprising an analog-to-digital converter configured to convert the amplified sampled signal into a digital signal and output a corresponding restored signal among the first restored signal and the second restored signal. According to claim 14,
The variable delay control signal is a radar device in the form of a sawtooth wave that linearly increases or decreases between a preset minimum value and a preset maximum value. According to claim 14,
The variable delay control signal is a radar device that non-linearly increases or decreases between a preset minimum value and a preset maximum value.

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