KR102305079B1 - Impulse radar transceiver for compensating path loss - Google Patents

Abstract

Impulse radar transceiver for path loss compensation according to an embodiment of the present invention, in the impulse radar transceiver, a receiving antenna for receiving an impulse signal reflected by a subject, and a received impulse signal according to an applied gain control signal It includes an amplifying unit for amplifying and a signal processing unit for applying a gain control signal to the amplifying unit, and the gain control signal may be generated based on a path loss curve of the impulse radar transceiver.

Description

IMPULSE RADAR TRANSCEIVER FOR COMPENSATING PATH LOSS

The present application relates to a radar transceiver capable of stably detecting both near and far distances by compensating for a loss along a radar path.

Unlike continuous wave (CW) radar or FMCW (Frequency Modulated CW) and frequency component analysis to determine distance and speed, impulse or pulsed CW radars ) Calculate distance and speed information by calculating the time it takes for a signal to depart from the transmitter and return to the receiver after it is reflected from the subject.

At this time, the path loss caused when the signal output from the transmitter is reflected back to the subject is reduced in proportion to the fourth power of the distance in both directions as shown in reference numeral 12 of FIG. 1 . Therefore, if the distance is increased by 10, the amplitude of the signal becomes 10000 times smaller, which is equivalent to 80 dB smaller.

In particular, in the case of applying the self-mixing method, as shown in reference numeral 11 of FIG. 1 , it becomes larger in proportion to the eighth square of the actual distance. Here, the self-mixing method is a method of using a received magnetic signal as a local signal without using a separate local oscillator.

Therefore, when there is a large difference between near and far in radar, it becomes very difficult to detect both near and far at the same time when performance such as transmit power and gain of a receiver are fixed and used.

As a method to solve this, in the case of FMCW, the distance appears as a frequency deviation, so it is a STC (Sensitivity Time Control) circuit using a filter with a high pass characteristic depending on the frequency in the IF band. There is a technique for compensating for the loss deviation according to the distance by setting the gain to be high in the low IF frequency band in the short distance.

On the other hand, in the impulse-type radar that measures the distance with a time delay, the received signal becomes very small as the distance increases due to the nature of the received signal that is reflected from a different distance depending on time, not the frequency component. You need to change it.

Japanese Patent Application Laid-Open No. 1999-125669 (“Pulse Radar Transceiver”, published on May 11, 1999)

The present invention provides an impulse radar transceiver for path loss compensation capable of generating an output signal of a constant size regardless of a distance from a subject.

According to an embodiment of the present invention, there is provided an impulse radar transceiver, comprising: a receiving antenna for receiving an impulse signal reflected by a subject; an amplifying unit amplifying the received impulse signal according to an applied gain control signal; and a signal processing unit that applies the gain control signal to the amplification unit, wherein the gain control signal is generated based on a path loss curve of the impulse radar transceiver.

According to an embodiment of the present invention, the signal processing unit is configured to step-wise control the gain control signal for each distance section from the subject based on an analog gain control curve having the same slope as the path loss curve of the impulse radar transceiver. a first memory in which the digital gain control signal is stored in the form of a table; and a controller for generating different digital gain control signals for each distance section from the subject by referring to the digital gain control table stored in the first memory and applying them to the amplifying unit; the amplifying unit, according to the applied digital gain control signal The impulse signal may be amplified for each distance section from the subject.

According to an embodiment of the present invention, the signal processing unit is configured to allow an output curve including an impulse signal amplified according to a digital gain control signal different for each distance section from the subject to have a constant size regardless of the distance from the subject. and a second memory for storing a gain shaping function of can

According to an embodiment of the present invention, the gain shaping function may be a curve symmetrical to the amplified impulse signal and the amplified impulse signal for each distance section from the subject, centered on the average value of the amplified impulse signal.

According to an embodiment of the present invention, the signal processing unit may include a digital-to-analog converter converting a digital gain control signal for each distance section with the subject stored in the digital gain control table of the first memory into an analog gain control curve. ; and a third memory configured to store the analog gain control curve converted by the digital-to-analog converter, wherein the controller refers to the analog gain control curve stored in the third memory to communicate with the subject. An analog gain control signal corresponding to the distance is generated and applied to the amplifying unit, and the amplifying unit amplifies the impulse signal according to the applied analog gain control signal, so that the amplified intensity of the impulse signal is equal to that of the subject. It can be made to have a constant size regardless of the distance.

According to an embodiment of the present invention, the impulse radar transceiver may be a transceiver using a self-mixing method.

According to an embodiment of the present invention, by performing the same gain control as the path loss curve in the impulse radar transceiver, it is possible to generate an output signal of a constant size regardless of the distance to the subject, and through this, the received impulse signal is Even when it is weak, the accuracy can be significantly improved, and the detection range can be secured more than that of the conventional impulse radar receiver.

1 is a diagram illustrating a path loss curve according to a distance of an impulse radar transceiver.
2 is a block diagram of an impulse radar transceiver for path loss compensation according to an embodiment of the present invention.
FIG. 3 is an internal block diagram of the signal processing unit shown in FIG. 2 .
4 is a diagram illustrating a digital gain control signal generated for each distance section from a subject.
5 is a view for explaining a process for compensating for a reflected signal amplified using a gain shaping function according to an embodiment of the present invention.
6 is a block diagram of an impulse radar transceiver for path loss compensation according to an embodiment of the present invention.
FIG. 7 is an internal block diagram of the signal processing unit shown in FIG. 6 .
8 is a diagram illustrating an analog gain control curve generated according to a distance from a subject.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiment of the present invention may be modified in various other forms, and the scope of the present invention is not limited only to the embodiments described below. The shapes and sizes of elements in the drawings may be exaggerated for clearer description, and elements indicated by the same reference numerals in the drawings are the same elements.

2 is a block diagram of an impulse radar transceiver for path loss compensation according to an embodiment of the present invention, and FIG. 3 is an internal block diagram of the signal processing unit shown in FIG. 2 .

Meanwhile, FIG. 4 is a diagram illustrating a digital gain control signal generated for each distance section from a subject, and FIG. 5 is a process for compensating for an amplified reflected signal using a gain shaping function according to an embodiment of the present invention. It is a drawing for explanation.

First, referring to FIG. 2 , the impulse radar transceiver 200 for path loss compensation according to an embodiment of the present invention includes a transmission module 110 for transmitting an impulse signal Tx through a transmission antenna ANT_T and , the receiving module 120 for receiving the impulse signal Rx reflected by the subject S through the receiving antenna ANT_R, and the signal processing unit 130 .

As shown in FIG. 2 , the transmission module 110 includes a delay lock loop (DLL) module 111 that generates a trigger clock and a sampling clock using an external crystal X-tal, and a DLL module 111 . The transmitter 112 may be configured to generate an impulse signal according to the generated trigger clock and transmit the generated impulse signal to the subject S through the transmission antenna ANT_T.

Meanwhile, the reception module 120 receives the impulse signal Tx reflected by the subject S through the reception antenna ANT_R, and controls the gain applied by the signal processing unit 130 to the received impulse signal Tx. The first amplifier 121 that primary amplifies according to the signal G_D, and the impulse signal Tx amplified by the first amplifier 121 are input to the local oscillator, and the impulse signal Rx is mixed through self-mixing. An envelope detector 122 for detecting an envelope, and a second amplifying unit 123 for secondary amplifying the envelope of the detected impulse signal Rx according to the gain control signal G_D applied from the signal processing unit 130; The ADC module 124 for converting the envelope of the secondly amplified impulse signal Rx into a digital value according to the sampling clock provided from the DLL module 111 may be included.

Meanwhile, the signal processing unit 130 generates a gain control signal G_D based on the path loss curve of the impulse radar transceiver, and converts the generated gain control signal G_D to the first amplifier 121 and the second amplifier ( 123) can be applied to at least one.

According to an embodiment of the present invention, the signal processing unit 130 may be configured to include a first memory 310 , a second memory 320 , and a control unit 330 as shown in FIG. 2 .

The first memory 310 of the signal processing unit 130 is a digital gain control signal for stepwise controlling the gain control signal for each distance section from the subject based on the analog gain control curve having the same slope as the path loss curve of the impulse radar transceiver. (G_D) may be stored in the form of a table.

That is, as shown in FIG. 4 , the first memory 310 transmits the gain control signal to the subject S based on the analog gain control curve 401 having the same slope as the path loss curve of the impulse radar transceiver. The digital gain control signal G_D for stepwise control by stars S1 to S4 may be stored in a table form.

According to this, when the distance of the subject S is input, the control unit 330 of the signal processing unit 130 refers to the digital gain control table stored in the first memory 310 and provides different digital gain control signals for each distance section from the subject. (G_D) may be generated and applied to at least one of the amplification units 121 and 123 .

Thereafter, the amplifying unit 121 and at least one of 123 may amplify the impulse signal for each distance section from the subject S according to the applied digital gain control signal G_D.

On the other hand, according to the embodiment of the present invention, the signal processing unit 130, the output curve including the impulse signal amplified according to the digital gain control signal (G_D) different for each distance section from the subject (S) with the subject (S) A second memory 320 that stores a gain shaping function to have a constant size regardless of distance may be further included.

According to this, the control unit 330 of the signal processing unit 130 compensates the amplified impulse signal according to the distance from the subject S with reference to the gain shaping function stored in the second memory 320, The output curve including the amplified impulse signal may have a constant size regardless of the distance from the subject S.

Here, the gain shaping function may be a symmetrical curve with the amplified impulse signal for each distance section from the subject S around the average value of the amplified impulse signal.

5 is a view for explaining a process for compensating for a reflected signal amplified using a gain shaping function according to an embodiment of the present invention. 5 (a) is a path loss curve, (b) is a digital gain control curve including a digital gain control signal (G_D) based on the analog gain control curve 401, (c) is a digital gain control signal (G_D) ), (d) shows the gain shaping function, and (e) shows the final output.

As shown in FIG. 5E , the impulse signal amplified according to the digital gain control signal G_D has a discontinuous value for each distance section S1 to S4 . Therefore, by compensating the amplified impulse signal shown in FIG. 5(c) according to the distance from the subject using the gain shaping function ((b) of FIG. 5) according to an embodiment of the present invention, the final output is As shown in (e) of FIG. 5 , it may have a constant size regardless of the distance from the subject.

Meanwhile, FIG. 6 is a block diagram of an impulse radar transceiver for path loss compensation according to an embodiment of the present invention, and FIG. 7 is an internal block diagram of the signal processing unit shown in FIG. 6 . Meanwhile, FIG. 8 is a diagram illustrating an analog gain control curve generated according to a distance from a subject.

Unlike FIG. 2 , the gain control signal G_D from the signal processing unit 130 of FIG. 2 is a digital gain control signal for controlling the gain for each section with the subject, whereas the gain control signal G_D from the signal processing unit 130 of FIG. 6 is The gain control signal G_A is different in that it is an analog gain control signal for continuously controlling a gain according to a distance from a subject.

Referring to FIG. 6 , an impulse radar transceiver 600 for path loss compensation according to an embodiment of the present invention includes a transmission module 110 for transmitting an impulse signal Tx through a transmission antenna ANT_T, and reception The receiving module 120 for receiving the impulse signal Rx reflected by the subject S through the antenna ANT_R and the signal processing unit 130 may be included.

As shown in FIG. 6 , the transmission module 110 includes a delay lock loop (DLL) module 111 that generates a trigger clock and a sampling clock using an external crystal X-tal, and a DLL module 111 . The transmitter 112 may be configured to generate an impulse signal according to the generated trigger clock and transmit the generated impulse signal to the subject S through the transmission antenna ANT_T.

Meanwhile, the reception module 120 receives the impulse signal Tx reflected by the subject S through the reception antenna ANT_R, and controls the gain applied by the signal processing unit 130 to the received impulse signal Tx. The first amplifier 121 that primary amplifies according to the signal G_A, and the impulse signal Tx amplified by the first amplifier 121 are input to the local oscillator, and the impulse signal Rx is mixed through self-mixing. An envelope detector 122 for detecting an envelope, and a second amplifying unit 123 for secondary amplifying the envelope of the detected impulse signal Rx according to the gain control signal G_A applied from the signal processing unit 130; The ADC module 124 for converting the envelope of the secondly amplified impulse signal Rx into a digital value according to the sampling clock provided from the DLL module 111 may be included.

Meanwhile, the signal processing unit 130 generates a gain control signal G_A based on the path loss curve of the impulse radar transceiver, and converts the generated gain control signal G_A to the first amplifier 121 and the second amplifier ( 123) can be applied to at least one.

According to an embodiment of the present invention, as shown in FIG. 7 , the signal processing unit 130 includes a first memory 310 , a D/A conversion unit 710 , a third memory 720 , and a control unit 730 . It may be composed of

As described above, the first memory 310 of the signal processing unit 130 includes a digital gain control signal G_D for stepwise controlling the gain control signal for each distance section (S1 to S4) from the subject S in a table. It may be stored in the form.

The digital-to-analog converter 710 of the signal processor 130 may convert the digital gain control signal G_D for each distance section with the subject stored in the first memory 310 into an analog gain control curve. In FIG. 7 , the digital-to-analog converter 710 is implemented in the signal processing unit 130 , but of course, it may be configured outside the signal processing unit 130 separately from the signal processing unit 130 .

The third memory 720 of the signal processor 130 may store the analog gain control curve converted by the digital-to-analog converter 710 .

According to this, the control unit 730 of the signal processing unit 130 generates an analog gain control signal G_A corresponding to the distance from the subject with reference to the analog gain control curve stored in the third memory 720 to generate the amplifying unit 121 . and at least one of 123).

Thereafter, the amplifying unit 121 and at least one of 123 amplifies the impulse signal according to the applied analog gain control signal G_A so that the intensity of the amplified impulse signal has a constant magnitude regardless of the distance from the subject. can

8 is a diagram illustrating a continuous gain control signal generated according to a distance from a subject. 8 (a) shows a path loss curve, (b) shows an analog gain control curve 401 stored in the third memory 720, and (e) shows an amplified impulse signal.

As shown in FIG. 8 , the digital gain control signal G_D stored in the first memory 310 is converted into an analog gain control curve 801 and stored in the third memory 720 , and then in the third memory 720 . ), generate an analog gain control signal G_A corresponding to the distance from the subject, and apply it to the amplifying unit 121 and 123, thereby continuously controlling gain according to the distance from the subject. is possible, and through this, as shown in (c) of FIG. 8 , the amplified impulse signal can have a constant size regardless of the distance from the subject.

As described above, according to an embodiment of the present invention, by performing the same gain control as the path loss curve in the impulse radar transceiver, an output signal having a constant size can be generated regardless of the distance to the subject.

The present invention can be mainly applied to an ETS (equivalent time sampling) type receiver. In general, it is practically impossible to implement an ADC circuit capable of high-speed sampling, so even if a low-speed ADC is used, high-speed sampling is virtually performed using a technique such as ETS (equivalent time sampling), which enables signal acquisition such as high-speed sampling. carry out

The above-mentioned ETS type receiver outputs the same impulse with a relatively low pulse repetition rate (PRF) of a relatively low period (several to several tens of MHz) and samples the reflected received signal each time, but the sampling time position is sampled at high speed. By sampling and collecting while moving using a time delay circuit at resolution intervals, and arranging them in order, the same data can be obtained as in the case of high-speed sampling at intervals of time resolution.

The present invention is not limited by the above-described embodiments and the accompanying drawings. It is intended to limit the scope of rights by the appended claims, and it is to those skilled in the art that various forms of substitution, modification and change can be made without departing from the technical spirit of the present invention described in the claims. it will be self-evident

110: sending module
111: DLL
112: transmitter
120: receive module
121: first amplification unit
122: envelope detector
123: second amplification unit
124: ADC
130: signal processing unit
310: first memory
320: second memory
330: control unit
401: analog gain control curve
402: digital gain control signal
710: D / A conversion unit
720: third memory

Claims (7)

delete An impulse radar transceiver comprising:
a receiving antenna for receiving the impulse signal reflected by the subject;
an amplifying unit amplifying the received impulse signal according to an applied gain control signal; and
a signal processing unit for applying the gain control signal to the amplification unit;
The gain control signal is generated based on a path loss curve of the impulse radar transceiver,
The signal processing unit,
a first memory in which a digital gain control signal is stored in a table form for stepwise controlling the gain control signal for each distance section from the subject based on an analog gain control curve having the same slope as the path loss curve of the impulse radar transceiver; and
a controller for generating different digital gain control signals for each distance section from the subject by referring to the digital gain control table stored in the first memory and applying them to the amplification unit;
The amplifying unit is configured to amplify the impulse signal for each distance section from the subject according to the applied digital gain control signal.
3. The method of claim 2,
The signal processing unit,
A second memory for storing a gain shaping function so that an output curve including an impulse signal amplified according to a different digital gain control signal for each distance section from the subject has a constant size regardless of the distance from the subject; and
The control unit is
and compensating the amplified impulse signal according to a distance from the subject with reference to the gain shaping function stored in the second memory.
4. The method of claim 3,
The gain shaping function is
An impulse radar transceiver, which is a curve of a symmetrical shape with the amplified impulse signal for each distance section from the subject, centering on the average value of the amplified impulse signal.
3. The method of claim 2,
The signal processing unit,
a digital-to-analog converter for converting a digital gain control signal for each distance section with the subject stored in the digital gain control table of the first memory into an analog gain control curve; and
The digital-to-analog converter further includes a third memory for storing the converted analog gain control curve;
The control unit generates an analog gain control signal corresponding to the distance from the subject with reference to the analog gain control curve stored in the third memory and applies the generated analog gain control signal to the amplifier;
The amplification unit, by amplifying the impulse signal according to the applied analog gain control signal, so that the intensity of the amplified impulse signal has a constant magnitude regardless of the distance to the subject.
An impulse radar transceiver comprising:
a receiving antenna for receiving the impulse signal reflected by the subject;
an amplifying unit amplifying the received impulse signal according to an applied gain control signal; and
a signal processing unit for applying the gain control signal to the amplification unit;
The gain control signal is generated based on a path loss curve of the impulse radar transceiver,
The signal processing unit,
a memory for storing an analog gain control curve having the same slope as a path loss curve of the impulse radar transceiver according to a distance from the subject; and
a controller for generating a different analog gain control signal according to a distance from the subject with reference to the analog gain control curve stored in the memory and applying it to the amplifying unit;
The amplification unit amplifies the impulse signal according to the applied analog gain control signal, so that the intensity of the amplified impulse signal has a constant magnitude regardless of a distance from the subject.
7. The method of any one of claims 2 and 6,
The impulse radar transceiver,
An impulse radar transceiver, a transceiver that uses a self-mixing method.

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