KR102467923B1 - Radar system and radar signal processing method performed thereby - Google Patents

Abstract

The present invention relates to a passenger monitoring radar system and a radar signal processing method performed therein. The method comprises the steps of: (a) removing, by a preprocessing unit, a fixed target included in a received signal and preprocessing to detect a biosignal which is a moving target; (b) storing, by a data buffer unit, the data preprocessed by the preprocessing unit and monitoring a power value of the signal; (c) detecting, by a multiple targets detection unit, multiple targets including the presence or absence of living things, 3D location information of the living things, and information on the number of living things through a multiple target detection signal processing process for the preprocessed data; and (d) detecting, by a biosignal detection unit, a biosignal including respiration and heart rate BPM of the living things. The present invention can remove the fixed object existing in a space to be detected, and detect the presence or absence of the living things, the 3D location information of the living things, the number of the living things, and biosignal information for each the living things.

Description

RADAR SYSTEM AND RADAR SIGNAL PROCESSING METHOD PERFORMED THEREBY}

The present invention relates to a radar system, and more particularly, to a passenger monitoring radar system for detecting living organisms existing inside a building or vehicle using a radar sensor and a radar signal processing method performed therein.

A radar sensor is a sensing means that transmits radio waves using microwaves and receives a partial reflection signal reflected from a target to measure distance, speed, and angle information.

Recently, radar sensors are being applied to vehicles to prevent collisions while driving and to support safe driving.

The present applicant has disclosed and registered a radar sensor technology in a number of patent documents 1 and 2 below.

Meanwhile, recently, a technology for detecting bio-signal information using a radar sensor has been developed.

In general, a bio-signal measuring device according to the prior art detects a respiratory rate or a heart rate using a contact sensor.

However, when it is difficult to use a contact sensor, such as a burn patient or an infant, a technology for detecting a biosignal using a radar sensor is being developed.

That is, among the biosignals, as the respiration signal and the heartbeat signal have periodicity, frequency modulated continuous wave (FMCW), continuous wave (CW), pulse, ultra wide band, UWB) radar sensors that use radio waves, such as radar, are used to detect periodic signal characteristics of biosignals to measure respiratory rate and heart rate.

As such, the radar sensor basically detects a target and detects biosignal information based on Doppler frequency characteristics of biosignals including respiration and heartbeat.

Since the Doppler frequency characteristic of the bio-signal changes very slowly at about 0.2 Hz to 1.0 Hz, the radar sensor used for detecting the bio-signal according to the prior art has a radar waveform period (PRI) for detecting the Doppler frequency characteristic of the bio-signal. should be designed long.

In addition, if the radar waveform period is designed to be long, the radar signal processing time increases, which slows down the bio-signal detection speed and slows down the response speed of the radar sensor.

In the case of using the FMCW radar waveform, since a lot of chirp data must be used, there is a problem in that the manufacturing cost of the radar sensor increases as the data memory (SRAM) to be stored increases.

Therefore, a technique capable of solving the above problems and detecting 3D spatial information including distance, azimuth, and elevation information for a plurality of living things and biometric information including respiration and heart rate BPM (beats per minute) of living things is developed. There is a growing need for

Korean Patent Registration No. 10-1513878 (published on April 22, 2015) Republic of Korea Patent Registration No. 10-1505044 (Announced on March 24, 2015)

An object of the present invention is to solve the above problems, and to provide a passenger monitoring radar system capable of detecting vital signals including respiration and heartbeat of a living creature having periodic characteristics and a radar signal processing method performed therein. is to provide

Another object of the present invention is a passenger surveillance radar system capable of removing fixed objects existing in a space to be detected, and detecting the presence or absence of living creatures, 3D location information of living creatures, the number of living creatures, and biosignal information for each living creature. And to provide a radar signal processing method performed therein.

In order to achieve the above object, the passenger monitoring radar system according to the present invention transmits a radar signal (hereinafter referred to as a 'transmission signal') toward a detection target and receives a reception signal reflected from the detection target; A radar transmitter for generating the transmit signal, a radar receiver for processing data of the received signal received through a receive antenna, and generating a control signal to generate the transmit signal and processing the received signal to detect biosignal information It includes a processor for signal processing, wherein the processor for signal processing includes a pre-processor for pre-processing the received signal, a data buffer for storing pre-processed data, and a multi-target for detecting multiple targets through a signal processing process for the pre-processed data. It is characterized in that it includes a detection unit and a bio-signal detection unit for detecting a bio-signal of a living body.

In addition, in order to achieve the above object, the radar signal processing method performed in the passenger monitoring radar system according to the present invention (a) removes the fixed target included in the received signal in the pre-processing unit, and the moving target bio signal (b) storing the data preprocessed by the preprocessor in the data buffer unit and monitoring the power value of the signal; (c) multiple target detection signals for the data preprocessed in the multi-target detection unit Through processing, detecting multiple targets including the presence or absence of living beings, 3D location information of living beings, and number information of living beings, and (d) detecting biosignals including respiration and heart rate BPM of living beings in a biosignal detection unit. It is characterized in that it includes the step of doing.

As described above, according to the passenger monitoring radar system and the radar signal processing method performed in the passenger monitoring radar system according to the present invention, it is possible to detect biosignals including respiration and heartbeat of living organisms having periodic characteristics.

And according to the present invention, the effect of removing the fixed object existing in the space to be detected, and detecting the presence or absence of living organisms, 3D location information of living organisms, the number of living creatures, and biosignal information for each living creature is obtained. .

That is, according to the present invention, an effect of improving the SNR by detecting a biosignal using an infinite number of received chirp signals through a plurality of receiving channels and applying a recursive average method is obtained.

In addition, according to the present invention, it is possible to improve the speed of detecting the presence/absence information of a living target by monitoring the power value of some data in the data buffer, and bio-signal information using only some data in the data buffer in which the target exists. (Doppler frequency) can be measured.

In addition, according to the present invention, in order to detect accurate biometric information, that is, respiration and biometric BPM, Doppler data is stored using a multi-layer I/Q data buffer based on the detected 3D target information, and Doppler signal processing is performed As a result, the effect of automatically matching the biometric information of living beings existing in the corresponding space without a separate matching process is obtained.

1 is a configuration diagram of a passenger monitoring radar system according to a preferred embodiment of the present invention;
2 is a diagram explaining a signal processing process of the radar signal processing unit shown in FIG. 1;
3 is a diagram explaining a process of pre-processing a received signal in a pre-processing unit;
4 is a diagram explaining the configuration of a data buffer unit;
5 is a diagram explaining a process of detecting multiple targets in a multi-target detection unit;
6 is a diagram explaining a process of detecting a biosignal in a biosignal detector;
7 is a flowchart illustrating a radar signal processing method performed in a passenger monitoring radar system according to a preferred embodiment of the present invention step by step.

Hereinafter, a passenger monitoring radar system and a radar signal processing method performed in the passenger monitoring radar system according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of a passenger monitoring radar system according to a preferred embodiment of the present invention, and FIG. 2 is a diagram explaining a signal processing process of the radar signal processing unit shown in FIG. 1 .

In this embodiment, the biosignal may be a signal obtained by detecting breathing of the detection target, a signal detected by heartbeat, or a signal detected by simultaneously detecting breathing and heartbeat.

As shown in FIGS. 1 and 2, the radar system 10 according to a preferred embodiment of the present invention transmits a radar signal (hereinafter referred to as a 'transmission signal') toward a detection target and receives a signal reflected from the detection target. The antenna unit 11 for receiving, the radar transmitter 12 for generating the transmission signal, the radar receiver 13 for processing the data of the received signal received through the receiving antenna 22, and control to generate the transmission signal It may include a signal processing processor 14 that generates a signal and processes the received signal to detect biosignal information.

The passenger monitoring radar system 10 configured as described above can be applied to various radar devices using various frequency bands such as 24 GHz, 60 GHz, 77 GHz, and 79 GHz.

The antenna unit 11 may include a transmission antenna 21 for transmitting a transmission signal and a reception antenna 22 for receiving a reception signal.

The radar transmitter 12 outputs a transmission signal of a desired oscillation frequency according to the control signal of the signal processing processor 14, and the radar receiver 13 amplifies the received signal and processes the data of the received signal. have.

The signal processing processor 14 includes a radar transmission control unit 41 that controls driving of the radar transmission unit 12, a radar reception control unit 42 that controls driving of the radar reception unit 13, and a communication unit that communicates with an external device. (43) and a radar signal processing unit 44 for detecting biosignal information through signal processing of the detected biosignal.

The radar transmission controller 41 may generate a control signal to adjust the radar waveform and transmission power (Tx Power) of the transmission signal.

The radar reception control unit 42 may generate a control signal to adjust the reception gain (Rx Gain) of the received signal and to adjust the band pad filter.

The radar reception controller 42 may include an analog-to-digital converter (hereinafter referred to as 'ADC') that converts the received signal Rx in the form of an analog signal into a digital signal.

That is, the radar reception control unit 42 includes a plurality of ADCs corresponding to the number of reception antennas 22, and each ADC may ADC-process the reception signal received through each reception antenna 22.

On the other hand, due to the characteristics of the biosignal consisting of inhalation and exhalation, a significant change in the Signal to Noise Ratio (SNR) of the received signal occurs.

Therefore, the present invention detects biosignals using received chirp signals continuously received through a plurality of receiving channels, and averages the detected data using a recursive average method to improve SNR.

In this way, when the recursive average method is applied, the response speed of the sensor is slowed down. Therefore, the present invention improves the target detection speed by monitoring the power value of some data in the data buffer.

In addition, when a large amount of chirp data is used for Doppler signal processing, the memory size must be increased. Accordingly, the present invention measures elevation and azimuth using only some data in which a target exists among data in a data buffer.

In addition, the present invention stores Doppler data using a multi-chapter I/Q data buffer for detected target information in order to detect accurate biometric information, that is, respiration and biometric BPM.

In addition, the present invention performs Doppler signal processing based on 3D target detection information in order to match biometric information with multi-target spatial information including distance, altitude, and azimuth to the target.

To this end, the radar signal processing unit 44 includes a preprocessing unit 51 for preprocessing the received signal, a data buffer unit 52 for storing the preprocessed data, and a signal processing process for the preprocessed data to detect multiple targets. It may include a target detector 53 and a biosignal detector 54 that detects a biosignal.

3 is a diagram explaining a process of pre-processing a received signal in a pre-processing unit, FIG. 4 is a diagram explaining the configuration of a data buffer unit, and FIG. 5 is a diagram explaining a process of detecting multiple targets in a multi-target detection unit, 6 is a diagram explaining a process of detecting a bio-signal in a bio-signal detector.

As shown in FIG. 3, the pre-processing unit 51 performs windowing and one-dimensional range FFT on ADC data converted from a received signal to a digital signal, and identifies a moving target. Indicator, hereinafter referred to as 'MTI') filters can be applied to remove fixed targets.

That is, the pre-processing unit 51 performs MTI-filtered data through a pre-processing process for each received signal received from a plurality of channels provided in the receiving antenna 21, for example, N channels (N is a positive integer), i.e., movement A target signal can be output.

Here, the receiving antenna 21 may be configured with various channels according to information to be detected, such as one-dimensional information corresponding to azimuth or two-dimensional information corresponding to azimuth and elevation information.

As shown in FIG. 4 , the data buffer unit 52 may include a plurality of, for example, M (M is a positive integer) data buffers for storing MTI-filtered data for each reception channel.

Each data buffer is configured to extract only MTI-filtered data (hereinafter referred to as 'MTI data') (A ₁ to A _N ) and specific distance data for each reception channel, for the distance detected from the multi-target detection unit 53. Index information (D) may be input.

So, each data buffer generates range, azimuth, and elevation map (Rang, Azimuth, Elevation Angle Map, hereinafter referred to as 'RAEM') data to be described below in the multi-target detection unit 53 and applies a recursive average method, MTI single data (B1) for each most recently received channel may be output.

In addition, each data buffer generates the RAEM data in the multi-target detector 53 and the bio-signal detector 54, and outputs all MTI-filtered data B2 for a specific distance for each channel to detect the Doppler frequency. can

In addition, each data buffer may output on/off control information (C) for a target detection operation in the multi-target detection unit 53.

Here, each data buffer may be provided with a size capable of storing as much sample data as corresponding to one cycle time of the minimum respiration signal.

Therefore, the multi-target detection unit 53 may measure the power of some of the most recently received MTI data to determine the presence or absence of a living creature.

Also, the multi-target detection unit 53 monitors the output of the MTI data and uses it as on/off control information for target detection. Accordingly, the present invention can rapidly improve the reaction speed of a detector for detecting multiple targets.

In detail, as shown in FIG. 5, the multi-target detection unit 53 receives the most recently received single MTI data B1 for each channel in order to generate the RAEM data and apply the recursive average method.

Also, the multi-target detection unit 53 monitors the power value of the MTI data and uses it as on/off control information for target detection.

Accordingly, the multi-target detector 53 may generate the RAEM data with the latest received MTI data B1 for each receive channel, which is data of a single chirp signal.

Here, the RAEM data may be prepared in the form of a RAEM data cube having distance, azimuth, and elevation.

Here, one-dimensional (1D) FFT may be used to detect distance, two-dimensional (2D) FFT to detect azimuth, and three-dimensional (3D) FFT to detect elevation.

In addition, the multi-target detection unit 53 may calculate an average of magnitude information of RAEM data to improve the SNR of the biosignal.

Here, as the multi-target detection unit 53 uses single chirp data, recursive type processing is applied, and multiple chirp data, that is, infinite chirp data, is used for averaging until the target disappears. This makes it possible to maximize the SNR.

Subsequently, the multi-target detection unit 53 may receive information C obtained by monitoring the power value of the MTI data, determine whether a target exists, and control on or off the target detection operation.

Thus, the multi-target detection unit 53 starts a target detection operation (on operation) when a target exists (for example, when C=1).

On the other hand, the multi-target detection unit 53 may stop the target detection operation (off operation) and generate a No Target Flag when the target does not exist (for example, when C = 0). .

Here, the multi-target detection unit 53 may output index information D for a distance detected from the 3D target detection data to each data buffer in order to extract only specific distance data.

Also, the multi-target detection unit 53 may perform clustering of the same target information for the detected 3-dimensional (distance, azimuth, elevation) targets.

Subsequently, the multi-target detection unit 53 may determine whether a target exists in a specific 3D spatial location using the clustered data and generate an alarm by executing warning logic.

As shown in FIG. 6, the biosignal detector 54 receives all MTI-filtered data B2 for a specific distance for each channel from each data buffer in order to generate the RAEM data and detect the Doppler frequency. can

In addition, the bio-signal detector 54 may receive index information D for the detected distance from the multi-target detector 53 .

Therefore, the bio-signal detector 54 may regenerate RAEM data using all MTI data at a specific distance by utilizing the detected distance information.

In addition, the bio-signal detector 54 detects the peak index of the peak signal having the highest signal intensity by using the detection information for each target in the RAEM data, and then processes the multiple I/Q data corresponding to the peak index. Can be stored in overlapping I/Q data buffers.

Next, the bio-signal detector 54 may detect bio-signal information including BPM of respiration and heartbeat using the stored multi-cheap I/Q data. That is, the bio-signal detector 54 detects bio-signal information including BPM of respiration and heartbeat by measuring bio-signal frequencies using chirp data included in stored multi-chirp I/Q data.

As such, in this embodiment, the multi-target detection unit and the bio-signal detection unit each repeatedly process RAEM data twice.

This requires a large amount of memory and takes a long processing time when the multi-target detection unit 53 generates RAEM data for all data in each data buffer.

Therefore, in this embodiment, as RAEM data is generated by recursive averaging, required memory can be minimized, processing time can be shortened by increasing processing speed, and SNR can be improved.

In addition, as the biosignal detector 54 regenerates RAEM data only for a specific distance at which the target exists using the detected information, it is possible to collect only I/Q data required for Doppler frequency detection using the detection information.

Accordingly, the bio-signal detection unit can minimize the memory of I/Q data for Doppler frequency detection and increase signal processing speed.

As such, the present invention can detect bio-signals including respiration and heartbeat of living organisms by using periodic characteristics of bio-signals.

In addition, the present invention can remove a fixed object existing in a space to be detected, and detect the presence or absence of a living creature, 3D location information of a living creature, the number of living creatures, and biosignal information for each living creature.

Next, with reference to FIG. 7, a radar signal processing method performed in a passenger monitoring radar system according to a preferred embodiment of the present invention will be described step by step.

7 is a flowchart illustrating a radar signal processing method performed in a passenger monitoring radar system according to a preferred embodiment of the present invention step by step.

In step S10 of FIG. 7 , the radar transmission/reception unit 12 is a detection target, that is, a target to detect a biosignal through the transmission antenna 21 according to the control signal of the radar transmission control unit 41 of the signal processing processor 14. (Hereinafter referred to as a 'biological target') and transmits a signal to the surroundings, and receives a signal reflected to the detection target through the receiving antenna 22.

In step S12, the ADC provided in the radar reception control unit 42 converts the received signal in the form of an analog signal into a digital signal.

In step S14, the pre-processing unit 51 provided in the radar signal processing unit 44 performs windowing and distance FFT on the ADC data, and removes fixed targets through filtering by applying an MTI filter (S16).

Thus, the data buffer unit 52 stores the MTI-filtered data for each receive channel in each data buffer (S18).

At this time, each data buffer stores MTI data (A ₁ to A _N ) for each reception channel, receives index information (D) for the detected distance from the multi-target detector 53, and outputs data for the corresponding distance. do.

That is, each data buffer outputs the most recently received MTI single data (B1) for each channel, outputs all MTI-filtered data (B2) for a specific distance for each channel, and detects the target in the multi-target detection unit 53. Outputs on/off control information (C) for the target detection operation.

In step S20, the multi-target detection unit 53 generates RAEM data with the latest received MTI data B1 for each receive channel, which is data of a single chirp signal.

In step S22, the multi-target detection unit 53 calculates an average of size information of the RAEM data. That is, as the multi-target detection unit 53 uses single chirp data, it applies recursive type processing and uses the effect of performing average with multiple chirp data, that is, infinite chirp data, until the target disappears. Thus, the SNR of the biosignal can be improved.

Meanwhile, in step S24, the multi-target detection unit 53 receives information (C) obtained by monitoring the power value of the MTI data stored in the data buffer unit 52, determines whether a target exists, and turns on or off the target detection operation. Control.

That is, in step S26, the multi-target detection unit 53 checks whether a target exists in the monitoring information.

If a target exists as a result of the inspection in step S26 (C=1), the multi-target detection unit 53 starts target detection signal processing to detect multiple targets (S28).

At this time, the multi-target detection unit 53 outputs index information D for a distance detected from the 3D target detection data to each data buffer in order to extract only specific distance data.

Subsequently, the multi-target detection unit 53 performs clustering to group the same target information for the detected 3-dimensional (distance, azimuth, elevation) target (S30), and uses the clustered data to locate a target in a specific 3D space. The presence or absence of a target is determined, and an alarm is generated according to the determined presence or absence of a target by executing a warning logic (S32).

On the other hand, if the target does not exist as a result of the inspection in step S26 (C=0), the target detection signal processing is not performed or stopped (off operation), and a No Target Flag is generated (S34). At this time, the multi-target detection unit 53 stops target detection signal processing and does not perform target BPM estimation at the same time. Subsequently, the multi-target detection unit 53 proceeds to step S24 and repeatedly checks whether a target exists by repeatedly monitoring the power value of the MTI data.

Through this process, the present invention can remove the fixed object existing inside the 3D space and accurately detect the biological target, that is, the presence or absence of a living creature, the 3D location information of the living creature, and the number of living creatures.

Meanwhile, in step S36, the bio-signal detector 54 receives MTI-filtered all data (B2) for a specific distance for each channel from each data buffer, and receives index information (D) for the distance detected from the multi-target detector 53. ) and regenerates RAEM data using all MTI data at a specific distance by using the detected distance information.

In addition, the bio-signal detector 54 uses the detection information for each target in the RAEM data, and uses the index for the peak signal having the highest signal intensity to generate multiple I/Q data for the corresponding index. It is stored in the Q data buffer (S38).

Subsequently, the biosignal detection unit 54 detects biosignal information including BPM of respiration and heartbeat using the stored multi-cheap I/Q data.

Through the process as described above, the present invention can detect biosignals including respiration and heartbeat of living creatures having periodic characteristics.

In addition, the present invention can remove a fixed object existing in a space to be detected, and detect the presence or absence of a living creature, 3D location information of a living creature, the number of living creatures, and biosignal information for each living creature.

Although the invention made by the present inventors has been specifically described according to the above embodiments, the present invention is not limited to the above embodiments, and various changes can be made without departing from the gist of the present invention.

The present invention removes fixed objects existing in a space to be detected, and detects the presence or absence of living creatures, 3D location information of living creatures, the number of living creatures, and biosignal information for each living creature, and a passenger surveillance radar system performed therein It is applied to radar signal processing method technology.

10: Radar system
11: antenna unit 12: radar transmission unit
13: radar receiver 14: processor for signal processing
21: transmit antenna 22: receive antenna
41: radar transmission control unit 42: radar reception control unit
43: communication unit 44: radar signal processing unit
51: pre-processing unit 52: MTI data buffer unit
53: multi-target detection unit 54: bio-signal detection unit

Claims (7)

In a radar signal processing method performed in a passenger monitoring radar system that transmits a radar signal toward a detection target and receives a signal reflected from the detection target to detect a biosignal,
(a) pre-processing in a pre-processing unit to remove a fixed target included in the received signal and to detect a biosignal that is a moving target;
(b) storing the data pre-processed by the pre-processing unit in a data buffer unit and monitoring the power value of the signal;
(c) detecting multiple targets including the presence or absence of living things, 3D location information of living things, and information on the number of living things through a multi-target detection signal processing process for data pre-processed by the multi-target detection unit; and
(d) detecting bio-signals including respiration and heart rate BPM of the organism detected as multiple targets in step (c) by the bio-signal detection unit;
Step (c) includes (c1) receiving data of a moving target identification (hereinafter referred to as 'MTI') single chirp signal for each channel most recently received from each data buffer in the multi-target detection unit;
(c2) generating distance, azimuth, and elevation map (hereinafter referred to as 'RAEM') data using the latest received MTI data for each received channel, which is data of a single chirp signal;
(c3) improving the signal-to-noise ratio (SNR) of the RAEM data by applying a recursive average method; and
(c4) determining whether a target exists by receiving information obtained by monitoring the power value of the MTI data stored in the data buffer unit, and controlling on or off of a target detection operation based on the determination result. A radar signal processing method performed in a passenger monitoring radar system. According to claim 1,
The step (a) is (a1) converting the received signal in analog form received through the receiving antenna into a digital signal using an analog-to-digital converter; and
(a2) A radar signal processing method performed in a passenger monitoring radar system comprising the step of removing a fixed target through an MTI filter after performing windowing and range FFT on the converted data. According to claim 1,
In the step (b), the data buffer unit stores the data filtered by the moving target identification filter for each receiving channel in a plurality of data buffers corresponding to the plurality of receiving channels, and indexes the distances detected by the multi-target detection unit. A radar signal processing method performed in a passenger monitoring radar system, characterized in that for receiving information and outputting data for a corresponding distance. delete According to claim 1,
In the step (c4), the multi-target detection unit detects the multi-target by starting target detection signal processing when the target exists,
A radar signal processing method performed in a passenger monitoring radar system, characterized in that when a target does not exist, a target detection operation is not performed or stopped, and a target no flag is generated. The method of claim 1, wherein step (d) is
(d1) The bio-signal detector receives all MTI-filtered data for a specific distance for each channel from each data buffer, receives index information on the detected distance from the multi-target detector, and uses the detected distance information to specify Regenerating RAEM data using all MTI data in the distance;
(d2) detecting index information for a peak signal having the highest signal intensity by using detection information for each target in the regenerated RAEM data, and storing multiple I/Q data corresponding to the peak index in each data buffer; and
(d3) detecting bio-signal information including respiration and heart rate BPM of the living body by measuring the bio-signal frequency using the chirp data included in the multi-chirp I/Q data stored in step (d2). A radar signal processing method performed in a surveillance radar system. In the passenger monitoring radar system for detecting bio signals by the radar signal processing method according to any one of claims 1 to 3, 5 and 6,
An antenna unit for transmitting a radar signal toward a detection target and receiving a reception signal reflected from the detection target;
a radar transmitter for generating the radar signal;
A radar receiving unit processing data of the received signal received through a receiving antenna; and
A signal processing processor for generating a control signal to generate the radar signal and processing the received signal to detect biosignal information;
The signal processing processor includes a pre-processing unit for pre-processing the received signal;
a data buffer unit for storing preprocessed data;
A multiple target detection unit that detects multiple targets through a signal processing process for preprocessed data; and
A passenger surveillance radar system comprising a bio-signal detector for detecting a bio-signal of a living body.

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