Microwave sensors for safety monitoring that improve false alarm rates related to biosignal detection

Abstract

The present invention relates to a microwave sensor for safety monitoring that improves the false alarm rate associated with biosignal detection. The sensor utilizes microwave signals to detect human bodies, animals, or objects approaching within a specified distance to monitor and determine false alarms or fault conditions caused by environmental factors. A pair of first and second Doppler radars are provided to process human detection signals and safety signals, respectively. This allows for a further expansion of the monitoring distance and the achievement of safety monitoring. Furthermore, a special intermediate frequency (IF) band susceptible to interference from the human body can be provided. To expand the monitoring distance (d), only the IF frequency can be amplified or the voltage level (peak-to-peak) can be changed to a DC voltage output. Furthermore, as the monitoring distance increases, a pair of sensors can transmit and receive safety signals to achieve double checks for precise management of the monitoring status. Consequently, compared to existing microwave sensors, false alarms or fault conditions of the sensor can be effectively distinguished, further improving the false alarm rate.

Description

Technical Field

[0001] The present invention relates to a sensor for security monitoring, and more specifically, to a microwave sensor for security monitoring that improves the false alarm rate associated with biological signal detection, namely, by using microwave signals to detect human bodies, animals, or objects approaching within a specified distance to determine false alarms or fault conditions caused by environmental factors. Background Art

[0002] Generally, a security system is installed in a place or space where life and property need to be protected in order to protect life and property from various crimes caused by unauthorized access or intrusion from the outside. In such a security system, various sensors for detecting intrusion from the outside are provided.

[0003] Sensors are devices that detect external stimuli or signals. They are devices that detect external signals or danger signals that are difficult for the human sensory organs to detect and convert them into electrical signals. Commonly used sensors include endoscopes, stethoscopes, thermometers, X-ray cameras, magnetic resonance imaging (MRI), and infrared cameras. Endoscopes use light to visualize the state of the stomach or intestines, while stethoscopes use sound to provide information about heartbeats, breathing, and blood circulation. Thermometers measure internal body temperature using heat, while X-ray cameras and MRIs use electromagnetic waves to indirectly display internal conditions that are invisible even with an endoscope. Infrared cameras convert infrared light emitted by objects into visible light, providing a clearer view of the surroundings.

[0004] Furthermore, radar, as a type of sensing technology, can accurately measure the distance to an object and its relative velocity to the observation point. Typically, radar devices operate by emitting microwave electromagnetic waves toward an object and receiving the waves reflected from the object. The processed signals are converted into a state that can be used by the operator or surrounding devices controlled by the radar. Target information is displayed on a cathode ray tube screen. The most widely used pulse radar transmits wireless energy in very strong pulses. Continuous wave radar, on the other hand, transmits signals continuously rather than in short pulses, requiring continuous reception of echoes. While simple continuous wave radars cannot measure distance, more complex frequency modulated continuous wave radars can. Optical radars emit very narrow laser beams instead of radio frequencies.

[0005] Doppler radar uses the Doppler effect of radio waves to detect moving targets based on the difference between the transmission frequency and the reflected frequency of radar waves emitted toward the target. It is used in weather radar, aircraft self-navigation systems, and military radars. In meteorological applications, it measures wind speed changes within clouds. In self-navigation systems, it calculates the current position by measuring the speed at which radio waves reach the ground. Military radars primarily use pulse Doppler radars, which typically use a single pulse signal to capture and track targets moving within waves reflected from the ground or sea surface.

[0006] exist Figure 1 Conventional Doppler radars consist of a transceiver. A microwave signal generated by a voltage-controlled oscillator within the transceiver, for example, at 24 GHz to 24.25 GHz, is output through a transmit antenna. This microwave signal is then reflected by a target, such as a person or object, and received by a receiver antenna. Furthermore, if the target moves, the signal received by the receiver antenna is converted into a Doppler-shifted signal relative to the transmit signal according to the target's speed, and received by the receiver antenna. Therefore, within the transceiver, the difference between the voltage-controlled oscillator's frequency signal and the received frequency signal passes through a mixer. The difference between the two signals is detected as a Doppler signal, which is converted into an intermediate frequency (baseband) signal at a specific voltage level and transmitted to the signal processing circuit. In this case, the Doppler signal detected as an intermediate frequency signal only occurs when the target moves, generating signals at varying voltage levels. If the movement ceases, the intermediate frequency signal also drops to zero.

[0007] Currently, infrared sensors, primarily used to detect human and object motion, suffer from short detection ranges, slow response times, high false alarm rates due to interference or interference from factors such as fog, fallen leaves, branches, birds, insects, temperature, and sunlight, and a narrow error range. Furthermore, existing Doppler radars require the use of modulated signals for long-distance radio wave transmission, or the need to process the received signal during detection in order to directly utilize the Doppler signal. This requires highly complex circuitry and expensive components on the receiving end, as well as software.

[0008] As prior art related to the present invention, Patent Document 1 discloses a motion detection device using a Doppler radar, comprising: a signal processor that receives a Doppler signal through the Doppler radar and calculates the average power value of the frequency components contained in the Doppler signal; and a motion determiner that receives the average power values ​​calculated for each of a plurality of Doppler signals continuously received by the Doppler radar from the signal processor and analyzes changes in the average power values ​​over time to determine the motion type of the reflector.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Korean Patent Publication No. 10-2019-0021906 (Publication Date: March 6, 2019) Summary of the Invention

[0012] Technical issues

[0013] In order to solve the above problems, the purpose of the present invention is to monitor and judge false alarms or failures caused by environmental factors by using a pair of transmitters and receivers in a Doppler radar transceiver structure to detect intruding biological signals within a set straight-line distance.

[0014] Furthermore, another object of the present invention is to reduce manufacturing costs and improve utilization by simplifying circuits while improving the false alarm rate.

[0015] Solutions to the Problem

[0016] In order to achieve the above-mentioned purpose, the microwave sensor for security monitoring provided by the present invention for improving the false alarm rate related to biological signal detection includes: a first Doppler radar, which is composed of a transmitter, and the above-mentioned transmitter generates an oscillation frequency of a specified period by applying a voltage from the outside, amplifies the generated oscillation frequency to a specified size, and then transmits it to the outside through a first transmitting antenna; and a second Doppler radar, which is composed of a transceiver, and the above-mentioned transceiver includes: a radar transceiver, which generates an oscillation frequency of a specified period by applying a voltage from the outside, amplifies the generated oscillation frequency to a specified size, and then transmits it to the outside through a second transmitting antenna, and transmits and receives the signals sent from the above-mentioned first transmitting antenna and the second transmitting antenna respectively through a first receiving antenna; a safety signal processing unit, wherein the first receiving antenna of the above-mentioned radar transceiver processes the intermediate frequency signal for security monitoring sent from the first transmitting antenna and converts it into a signal of a specified size. a first DC voltage level and outputs it; a human body detection signal processing unit, in which the first receiving antenna of the above-mentioned radar transceiver processes the Doppler intermediate frequency signal generated by the reflected wave of the detection object approaching the monitoring area and sent from the second transmitting antenna, converts it into a second DC voltage level of a specified size and outputs it; and a comparison unit, which compares the first DC voltage level input from the above-mentioned safety signal processing unit with the second DC voltage level input from the human body detection signal processing unit, and outputs the result value, respectively receiving the signal sent by the above-mentioned first transmitting antenna within the specified monitoring area through the monitoring distance (d) and the signal reflected by the monitored object sent by the above-mentioned second transmitting antenna within the specified monitoring range through the first receiving antenna, and after performing signal processing in the safety signal processing unit and the human body detection signal processing unit respectively, detects the monitoring object approaching, moving slightly or in a stopped state and identifies sensor failure.

[0017] Furthermore, the present invention may further include a determination unit for determining whether the state is abnormal based on a value outputted after the comparison unit compares the first DC voltage level with the second DC voltage level and the first DC voltage level inputted from the safety signal processing unit.

[0018] Furthermore, in the present invention, the judgment unit makes a judgment based on the result value input by the comparison unit. When the first DC voltage level is high (High) and the second DC voltage level is high (High), it is judged that the monitored object is approaching; when the first DC voltage level is high (High) and the second DC voltage level is low (Low), it is judged to be in a normal monitoring state; when the first DC voltage level is middle (Middle) and the second DC voltage level is high (High), it is judged that the monitored object exists in the monitoring area; when the first DC voltage level is middle (Middle) and the second DC voltage level is low (Low), it is judged to be in a normal monitoring state; when the first DC voltage level is low (Low) and the second DC voltage level is high (High), it is judged to be in a normal monitoring state; when the first DC voltage level is low (Low) and the second DC voltage level is high (High), it is judged to be an intrusion of the monitored object; and when the first DC voltage level is low (Low) and the second DC voltage level is low (Low), it can be judged to be a false alarm caused by a sensor failure.

[0019] Furthermore, in the present invention, the radar transceiver may include a filter configured to filter the security monitoring intermediate frequency signal and the Doppler intermediate frequency signal in predetermined frequency bands.

[0020] Furthermore, the microwave sensor for safety monitoring provided by the present invention for improving the false alarm rate associated with biological signal detection includes a first Doppler radar and a second Doppler radar. The first Doppler radar is composed of a first transceiver, which includes: a first radar transceiver that generates an oscillation frequency of a specified period by applying a voltage from the outside, amplifies the generated oscillation frequency to a specified magnitude, and transmits it to the outside through a first transmitting antenna. After being transmitted from the first transmitting antenna, a reflected wave signal reflected by the detection object and a signal transmitted from the second transmitting antenna of the second transceiver are respectively transmitted and received through a first receiving antenna; a first safety signal processing unit that processes the intermediate frequency signal for safety monitoring transmitted from the second transmitting antenna of the second radar transceiver of the second transceiver and received by the first receiving antenna of the first radar transceiver, converts the signal into a first DC voltage level of a specified magnitude, and outputs the signal; a first human body detection signal processing unit that processes the Doppler intermediate frequency signal generated by the reflected wave of the detection object approaching the monitoring area and transmitted from the first transmitting antenna and received by the first receiving antenna of the first radar transceiver, converts the signal into a second DC voltage level of a specified magnitude, and outputs the signal; a comparing unit for comparing a first DC voltage level input from the first safety signal processing unit with a second DC voltage level input from the first human detection signal processing unit, and outputting a result value; the second Doppler radar comprising a second transceiver, comprising: a second radar transceiver for generating an oscillation frequency of a predetermined period using an externally applied voltage, amplifying the generated oscillation frequency to a predetermined level, and transmitting the oscillation frequency to the outside via a second transmitting antenna; and, after transmission from the second transmitting antenna, transmitting and receiving, via a second receiving antenna, a reflected wave signal reflected from a detection object and a signal transmitted from the first transmitting antenna of the first transceiver; a second safety signal processing unit for processing a safety monitoring intermediate frequency signal transmitted from the first transmitting antenna of the first transceiver and received by the second receiving antenna of the second radar transceiver, converting the signal to a third DC voltage level of a predetermined level, and outputting the result; and a second human detection signal processing unit for processing a Doppler intermediate frequency signal generated by a reflected wave transmitted from the second transmitting antenna of the second radar transceiver and received by the second receiving antenna of the second radar transceiver, converting the signal to a fourth DC voltage level of a predetermined level, and outputting the result.The second comparing unit compares the third DC voltage level input from the second safety signal processing unit with the fourth DC voltage level input from the second human detection signal processing unit, and outputs a result value. The second comparing unit receives, via the first receiving antenna and the second receiving antenna, signals transmitted by the first transmitting antenna and the second transmitting antenna, respectively, within a predetermined monitoring area and across a monitoring distance (d), as well as signals reflected by the first transmitting antenna and the second transmitting antenna, respectively, from a detection object within the predetermined monitoring area, so that the first human detection signal processing unit and the second human detection signal processing unit can respectively detect Doppler intermediate frequency signals for a detection object within the predetermined monitoring area and within the monitoring distance (d). After the first safety signal processing unit, the first human detection signal processing unit, the second safety signal processing unit, and the second human detection signal processing unit respectively perform signal processing, the second comparing unit detects a detection object approaching, slightly moving, or stationary, and identifies a sensor failure.

[0021] In addition, the present invention may also include: a first judgment unit, which judges whether the state is abnormal based on the value output after the above-mentioned first comparison unit compares the first DC voltage level with the second DC voltage level and the first DC voltage level input from the first safety signal processing unit; and a second judgment unit, which judges whether the state is abnormal based on the value output after the above-mentioned second comparison unit compares the third DC voltage level with the fourth DC voltage level and the third DC voltage level input from the second safety signal processing unit.

[0022] Furthermore, in the present invention, the first judgment unit makes a judgment based on the result value input by the first comparison unit, and the second judgment unit makes a judgment based on the result value input by the second comparison unit. When the first DC voltage level is high (High), the second DC voltage level is low (Low), the third DC voltage level is high (High), and the fourth DC voltage level is low (Low), it is judged to be a normal monitoring state. When the first DC voltage level is high (High), the second DC voltage level is low (Low), the third DC voltage level is high (High), and the fourth DC voltage level is high (High), it is judged by the second Doppler radar that the monitored object is approaching. When the first DC voltage level is high (High), the second DC voltage level is low (Low), the third DC voltage level is high (High), and the fourth DC voltage level is high (High), it is judged that the monitored object is approaching. When the first DC voltage level is high (High), the third DC voltage level is high (High), and the fourth DC voltage level is low (Low), the first Doppler radar determines that the monitored object is approaching; when the first DC voltage level to the fourth DC voltage level are all high (High), it is determined that the monitored object is approaching within the monitoring distance; when the first DC voltage level is low (Low), the second DC voltage level is high (High) or low (Low), the third DC voltage level is low (Low), and the fourth DC voltage level is high (High) or low (Low), it is determined that the monitored object is intruding; when the first DC voltage level to the fourth DC voltage level are all low (Low), it can be determined that it is a false alarm caused by a sensor failure.

[0023] Furthermore, in the present invention, the first radar transceiver and the second radar transceiver may respectively include filters, and the filters are used to filter the security monitoring intermediate frequency signal and the Doppler intermediate frequency signal in a predetermined frequency band.

[0024] Effects of the Invention

[0025] The present invention has the following advantages: it can improve the shortcomings of existing microwave sensors, which require very complex circuits and expensive components in the receiver in order to use modulated signals or directly use Doppler signals, and also require the use of software. Instead of configuring software, a sensor of equivalent quality can be achieved by simply inserting a simple circuit using a radio frequency transceiver module. Furthermore, by providing a pair of first and second Doppler radars that process human body detection signals and safety signals, respectively, the monitoring distance can be further extended and safety monitoring can be achieved. Furthermore, a special intermediate frequency band that is susceptible to human interference can be specially designed. To extend the monitoring distance (d), only the intermediate frequency can be amplified or the voltage level (peak to peak) can be changed to a DC voltage output. Furthermore, as the monitoring distance increases, a pair of sensors can transmit and receive safety signals to each other, achieving double checks and precise management of the monitoring status. Therefore, compared to existing microwave sensors, false alarms or malfunctions of the sensor can be effectively distinguished, further improving the false alarm rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a diagram showing the operation of a conventional Doppler radar.

[0027] Figure 2 FIG1 is a block diagram showing a microwave sensor for security monitoring that improves the false alarm rate associated with biological signal detection according to a first embodiment of the present invention.

[0028] Figure 3 This is a graph showing the results of the determination unit in the safety monitoring microwave sensor for improving the false alarm rate related to biological signal detection according to the present invention determining the monitoring state based on the DC voltage level output by the comparison unit.

[0029] Figure 4 FIG. 1 is a block diagram illustrating a microwave sensor for security monitoring that improves the false alarm rate associated with biological signal detection according to a second embodiment of the present invention.

[0030] Figure 5 This is a graph showing the results of the first and second determination units in the safety monitoring microwave sensor for improving the false alarm rate related to biological signal detection according to the present invention determining the monitoring state based on the DC voltage levels output by the first and second comparison units. DETAILED DESCRIPTION

[0031] Hereinafter, with reference to the accompanying drawings, a microwave sensor for security monitoring according to a first embodiment of the present invention, which improves the false alarm rate associated with bio-signal detection, will be described in detail.

[0032] exist Figure 2In the embodiment, the first Doppler radar 10 and the second Doppler radar 20 are separated from each other by a monitoring distance d set within a specified range for transmitting and receiving microwave frequencies. Preferably, the first Doppler radar 10 and the second Doppler radar 20 are symmetrically arranged so as to face each other.

[0033] The first Doppler radar 10 is composed of a transmitter 11 . The transmitter 11 generates an oscillation frequency of a predetermined period by a voltage applied from the outside, amplifies the generated oscillation frequency to a predetermined level, and transmits the amplified oscillation frequency to the outside via a first transmitting antenna Tx1 .

[0034] The second Doppler radar 20, corresponding to the first Doppler radar 10, comprises a transceiver 21 for transmitting and receiving oscillation frequencies. The radar transceiver 22 of the second Doppler radar 20 generates an oscillation frequency of a predetermined period using an externally applied voltage. After amplifying the generated oscillation frequency to a predetermined level, it is transmitted externally via the second transmitting antenna Tx2. Furthermore, the transceiver 21 transmits and receives signals transmitted from the first transmitting antenna Tx1 of the first Doppler radar 10 and the second transmitting antenna Tx2 of the second Doppler radar 20, respectively, via the first receiving antenna Rx1.

[0035] Furthermore, after the first receiving antenna Rx1 of the radar transceiver 22 processes the safety monitoring intermediate frequency signal transmitted from the first transmitting antenna Tx1, the safety signal processing unit 23 converts the signal to a predetermined first DC voltage level and outputs it. Furthermore, after the first receiving antenna Rx1 connected to the radar transceiver 22 processes the Doppler intermediate frequency signal generated by the reflected wave transmitted from the second transmitting antenna Tx2 by a detection object near the monitoring area, the human body detection signal processing unit 24 converts the signal to a predetermined second DC voltage level and outputs it. Furthermore, the radar transceiver 22 includes filters for filtering the safety monitoring intermediate frequency signal and the Doppler intermediate frequency signal within predetermined frequency bands.

[0036] The comparison unit 25 of the second Doppler radar 20 compares the first DC voltage level input from the safety signal processing unit 23 and the second DC voltage level input from the human body detection signal processing unit 24 , and outputs the result values.

[0037] In addition, the transceiver 21 of the second Doppler radar 20 includes a judgment unit 26, which judges the normal working state or abnormal state of the microwave sensor for safety monitoring based on the value output after the comparison unit 25 compares the first DC voltage level and the second DC voltage level and the first DC voltage level input from the safety signal processing unit 23.

[0038] Furthermore, based on the signal received from the judgment device 26, an alarm can be issued to the monitoring person in charge of the presence of an intruder in the monitoring area, approaching or passing through, and monitoring can be achieved.

[0039] Hereinafter, the effects of the microwave sensor for safety monitoring having the above-mentioned structure and improving the false alarm rate related to biological signal detection according to the first embodiment of the present invention will be described.

[0040] First, the first transmitting antenna Tx1 of the first Doppler radar 10 transmits a frequency signal oscillating within a specified monitoring area and across a monitoring distance d. The signal transmitted from the first transmitting antenna Tx1 is received by the first receiving antenna Rx1 of the second Doppler radar 20. Furthermore, the signal transmitted from the second transmitting antenna Tx2 of the second Doppler radar 20 is reflected by an object within the specified monitoring area and then received by the first receiving antenna Rx1. In this case, the radar transceiver 22 of the second Doppler radar 20 filters the frequency signals received by the first receiving antenna Rx1 from the first transmitting antenna Tx1 and the second transmitting antenna Tx2, respectively. Typically, the Doppler intermediate frequency signal for people, animals, or objects moving at speeds below 100 km / h has a frequency characteristic of approximately several hundred Hz. However, this frequency deviation from the randomly set intermediate frequency signal for security monitoring is significant, so filters in the corresponding frequency bands can easily separate the two signals.

[0041] The intermediate frequency signal for security monitoring separated from the radar transceiver 22 is processed by the security signal processing unit 23 and converted into a first DC voltage level output. The Doppler intermediate frequency signal reflected by a human body, animal or object close to the monitoring area is processed by the human body detection signal processing unit 24 and converted into a second DC voltage level output.

[0042] Therefore, if the transceiver 21 of the second Doppler radar 20 performs signal processing on the signal received from the first receiving antenna Rx1 through the safety signal processing unit 23 and the human body detection signal processing unit 24 to output a first DC voltage level and a second DC voltage level, respectively, the judgment unit 26 can detect a monitoring object approaching between the first Doppler radar 10 and the second Doppler radar 20 or identify a sensor failure.

[0043] exist Figure 3In the example, the judgment unit 26 judges the result value input from the comparison unit 25. Specifically, if the first DC voltage level is high (High) and the second DC voltage level is high (High), the judgment unit 26 judges that the monitored object is approaching. Furthermore, if the first DC voltage level is high (High) and the second DC voltage level is low (Low), the judgment unit 26 judges that the monitored object is in a normal monitoring state. Furthermore, if the first DC voltage level is middle (Middle) and the second DC voltage level is high (High), the judgment unit 26 judges that the monitored object is present in the monitoring area corresponding to the alarm area and monitoring is being achieved. Alternatively, if the first DC voltage level is middle (Middle) and the second DC voltage level is low (Low), the judgment unit 26 judges that the monitored object is in a normal monitoring state. Furthermore, if the first DC voltage level is low (Low) and the second DC voltage level is high (High), the judgment unit 26 judges that the monitored object has intruded; if the first DC voltage level is low (Low) and the second DC voltage level is low (Low), it is judged as a false alarm caused by a sensor failure and the sensor is maintained and repaired.

[0044] Furthermore, since the human body detection signal processing unit 24 included in the transceiver 21 of the second Doppler radar 20 can detect subtle movements such as breathing, the presence and approach of the monitored object can be determined even when the monitored object is hidden, covered, or stopped.

[0045] As described above, as the first receiving antenna Rx1 of the second Doppler radar 20 receives the signal transmitted by the first transmitting antenna Tx1 of the first Doppler radar 10 within the specified monitoring area and across the monitoring distance d, and the signal reflected by the second transmitting antenna Tx2 from the monitored object within the specified monitoring range, the safety signal processing unit 23 and the human detection signal processing unit respectively process the safety monitoring intermediate frequency signal and the Doppler intermediate frequency signal to detect the approach or presence of the monitored object within the monitoring area, thereby identifying sensor failures. This allows not only the detection of humans, animals, or objects approaching the monitoring area, but also the detection and determination of false alarms and sensor failures caused by environmental factors during safety monitoring, thereby enabling more effective security monitoring.

[0046] Next, a second embodiment of the microwave sensor for security monitoring that improves the false alarm rate associated with bio-signal detection according to the present invention will be described.

[0047] exist Figure 4 In the embodiment, the third Doppler radar 30 and the fourth Doppler radar 40 are separated from each other by a monitoring distance d set within a specified range for transmitting and receiving microwave frequencies. Preferably, the third Doppler radar 30 and the fourth Doppler radar 40 are arranged to face each other.

[0048] The third Doppler radar 30 is located at a position corresponding to the fourth Doppler radar 40 and comprises a first transceiver 31 for transmitting and receiving oscillation frequencies. The first radar transceiver 32 of the third Doppler radar 30 generates an oscillation frequency of a predetermined period using an externally applied voltage. After amplifying the generated oscillation frequency to a predetermined level, it is transmitted externally via the first transmitting antenna Tx1. Furthermore, the first transceiver 31 transmits and receives signals transmitted from the first transmitting antenna Tx1 of the third Doppler radar 30 and the second transmitting antenna Tx2 of the fourth Doppler radar 40 via the first receiving antenna Rx1.

[0049] The first receiving antenna Rx1 of the first radar transceiver 32 processes the safety monitoring intermediate frequency signal transmitted from the second transmitting antenna Tx2 of the second transceiver 41. The first safety signal processing unit 33 then converts the signal to a predetermined first DC voltage level and outputs the signal. Furthermore, after the first receiving antenna Rx1 connected to the first radar transceiver 32 processes the Doppler intermediate frequency signal generated by the reflected wave transmitted from the first transmitting antenna Tx1 and reflected by an object approaching the monitoring area, the first human detection signal processing unit 34 converts the signal to a predetermined second DC voltage level and outputs the signal. Furthermore, the first radar transceiver 32 includes filters for filtering the safety monitoring intermediate frequency signal and the Doppler intermediate frequency signal within predetermined frequency bands.

[0050] The first comparison unit 35 of the third Doppler radar 30 compares the first DC voltage level input from the first safety signal processing unit 33 and the second DC voltage level input from the first human body detection signal processing unit 34 , and outputs the result values.

[0051] In addition, the first transceiver 31 of the third Doppler radar 30 includes a first judgment unit 36, which judges the normal working state or abnormal state of the microwave sensor for safety monitoring based on the value output after the first comparison unit 35 compares the first DC voltage level and the second DC voltage level and the first DC voltage level input from the first safety signal processing unit 33.

[0052] Meanwhile, the fourth Doppler radar 40 is located at a position corresponding to the third Doppler radar 30 and comprises a second transceiver 41 for transmitting and receiving oscillation frequencies. The second radar transceiver 42 of the fourth Doppler radar 40 generates an oscillation frequency of a predetermined period using an externally applied voltage. After amplifying this generated oscillation frequency to a predetermined level, it is transmitted externally via the first transmitting antenna Tx1. Furthermore, the second transceiver 41 transmits and receives signals transmitted from the first transmitting antenna Tx1 of the third Doppler radar 30 and the second transmitting antenna Tx2 of the fourth Doppler radar 40 via the second receiving antenna Rx2.

[0053] The second receiving antenna Rx2 of the second radar transceiver 42 processes the safety monitoring intermediate frequency signal transmitted from the first transmitting antenna Tx1 of the first transceiver 31. The second safety signal processing unit 43 then converts the signal to a predetermined third DC voltage level and outputs the signal. Furthermore, after the second receiving antenna Rx2 connected to the second radar transceiver 42 processes the Doppler intermediate frequency signal generated by the reflected wave transmitted from the second transmitting antenna Tx2 and reflected by an object approaching the monitoring area, the second human detection signal processing unit 44 converts the signal to a predetermined fourth DC voltage level and outputs the signal. Furthermore, the second radar transceiver 42 includes filters for filtering the safety monitoring intermediate frequency signal and the Doppler intermediate frequency signal within predetermined frequency bands.

[0054] The second comparison unit 45 of the fourth Doppler radar 40 compares the third DC voltage level input from the second safety signal processing unit 43 and the fourth DC voltage level input from the second human body detection signal processing unit 44 , and outputs the result values.

[0055] In addition, the second transceiver 41 of the fourth Doppler radar 40 includes a second judgment unit 46, which judges the normal working state or abnormal state of the microwave sensor for safety monitoring based on the value output after the second comparison unit 45 compares the third DC voltage level with the fourth DC voltage level and the third DC voltage level input from the second safety signal processing unit 43.

[0056] Furthermore, based on the signals received from the first judgment device 36 and the second judgment unit 46 , an alarm can be issued to the monitoring person in charge of the presence of an intruder in the monitoring area, approaching or passing through, and monitoring can be achieved.

[0057] Hereinafter, the functions of the microwave sensor for security monitoring having the above-mentioned structure and improving the false alarm rate related to biological signal detection according to the second embodiment of the present invention will be described.

[0058] First, a frequency signal oscillating within a predetermined monitoring area and over a monitoring distance d is transmitted from the first transmitting antenna Tx1 of the third Doppler radar 30. The signal transmitted from the first transmitting antenna Tx1 is received by the second receiving antenna Rx2 of the fourth Doppler radar 40. Furthermore, the signal transmitted from the first transmitting antenna is reflected by a monitoring object within the predetermined monitoring area and is then received by the first receiving antenna Rx1.

[0059] Furthermore, a frequency signal oscillating within the predetermined monitoring area and over a monitoring distance d is transmitted from the second transmitting antenna Tx2 of the fourth Doppler radar 40. The signal transmitted from the second transmitting antenna Tx2 is received by the first receiving antenna Rx1 of the third Doppler radar 30. Furthermore, the signal transmitted from the second transmitting antenna is reflected by a monitoring object within the predetermined monitoring area and is then received by the second receiving antenna Rx2.

[0060] The first transceiver 31 of the third Doppler radar 30 includes a first radar transceiver 32 that filters the frequency signals received by the first receiving antenna Rx1 from the first transmitting antenna Tx1 and the second transmitting antenna Tx2. Furthermore, the safety monitoring intermediate frequency signal separated from the first radar transceiver 32 is processed by the first safety signal processing unit 33 and converted to a first DC voltage level for output. The Doppler intermediate frequency signal reflected by a human, animal, or object approaching the monitoring area is processed by the first human detection signal processing unit 34 and converted to a second DC voltage level for output.

[0061] When the first transceiver 31 of the third Doppler radar 30 processes the signal received from the first receiving antenna Rx1 through the first safety signal processing unit 33 and the first human detection signal processing unit 34, respectively, to output a first DC voltage level and a second DC voltage level, the first determination unit 36 ​​determines whether the state is abnormal based on the value output by the first comparison unit 35 after comparing the first DC voltage level with the second DC voltage level, and the first DC voltage level input from the first safety signal processing unit 33. Thus, the first determination unit 36 ​​can detect a monitored object approaching between the third Doppler radar 30 and the fourth Doppler radar 40 or identify a sensor failure.

[0062] Furthermore, the second radar transceiver 42 included in the second transceiver 41 of the fourth Doppler radar 40 filters the frequency signals received by the second receiving antenna Rx2 from the first transmitting antenna Tx1 and the second transmitting antenna Tx2, respectively. Furthermore, the safety monitoring intermediate frequency signal separated from the second radar transceiver 42 is processed by the second safety signal processing unit 43 and converted to a third DC voltage level for output. The Doppler intermediate frequency signal reflected by a human, animal, or object approaching the monitoring area is processed by the second human detection signal processing unit 44 and converted to a fourth DC voltage level for output.

[0063] When the second transceiver 41 of the fourth Doppler radar 40 processes the signal received from the second receiving antenna Rx2 via the second safety signal processing unit 43 and the second human detection signal processing unit 44, respectively, to output a third DC voltage level and a fourth DC voltage level, the second determination unit 46 determines whether the state is abnormal based on the value output by the second comparison unit 45 after comparing the third DC voltage level with the fourth DC voltage level, and the third DC voltage level input from the second safety signal processing unit 43. Thus, the second determination unit 46 can detect the proximity of a monitored object between the third Doppler radar 30 and the fourth Doppler radar 40 or identify a sensor failure.

[0064] exist Figure 5 In the example, the first determination unit 36 ​​makes a determination based on the result value input from the first comparison unit 35, and the second determination unit 46 makes a determination based on the result value input from the second comparison unit 45. Specifically, if the first DC voltage level is High, the second DC voltage level is Low, the third DC voltage level is High, and the fourth DC voltage level is Low, the first and second determination units 36 and 46 determine that the monitoring state is normal. Furthermore, if the first DC voltage level is High, the second DC voltage level is Low, the third DC voltage level is High, and the fourth DC voltage level is High, the first and second determination units 36 and 46 determine that the monitoring object is approaching via the second Doppler radar 20. Alternatively, if the first DC voltage level is High, the second DC voltage level is High, the third DC voltage level is High, and the fourth DC voltage level is Low, the first and second determination units 36 and 46 determine that the monitoring object is approaching via the first Doppler radar 10. Furthermore, if the first through fourth DC voltage levels are all high, it is determined that a monitored object, such as a person, animal, or large object, is approaching within the monitoring distance. If the first DC voltage level is low, the second DC voltage level is high or low, the third DC voltage level is low, and the fourth DC voltage level is high or low, it is determined that the monitored object is intruding. Furthermore, if the first through fourth DC voltage levels are all low, it is determined to be a false alarm caused by a sensor failure, and the sensor should be repaired. Furthermore, if none of the first through fourth DC voltage levels are high or low, it is determined to be normal, or appropriate measures should be determined after monitoring by monitoring personnel.

[0065] Furthermore, since the first human detection signal processing unit 34 included in the first transceiver 31 of the third Doppler radar 30 and the second human detection signal processing unit 44 included in the second transceiver 41 of the fourth Doppler radar 40 can detect minute movements such as breathing, the presence and proximity of the monitored object can be determined even when the monitored object is hidden, covered, or stopped.

[0066] As described above, as the first receiving antenna Rx1 of the third Doppler radar 30 and the second receiving antenna Rx2 of the fourth Doppler radar 40 receive signals transmitted by the first transmitting antenna Tx1 of the third Doppler radar 30 and the second transmitting antenna Tx2 of the fourth Doppler radar 40 within the specified monitoring area and across the monitoring distance d, as well as signals reflected by monitored objects within the specified monitoring range, the first and second safety signal processing units 33 and 43, and the first and second human detection signal processing units 34 and 44 respectively process the safety monitoring intermediate frequency signals and the Doppler intermediate frequency signals to detect the approach or presence of monitored objects within the monitoring area, thereby identifying sensor failures. This allows not only the detection of humans, animals, or objects approaching the monitoring area, but also the detection and determination of false alarms and sensor failures caused by environmental factors during safety monitoring, thereby enabling more effective security monitoring.

[0067] Thus, the second embodiment of the present invention further extends the monitoring range and achieves safe monitoring by providing a pair of first and second transceivers 31 and 41 for processing human detection signals and safety signals, respectively. Furthermore, as the monitoring range increases, the pair of sensors can transmit and receive safety signals to each other, achieving a double check and precise management of the monitoring status, effectively distinguishing between false alarms and sensor failures.

[0068] Since the microwave sensor for security monitoring of the present invention that improves the false alarm rate related to biological signal detection can be specially designed with an intermediate frequency band that is interfered with by the human body, in order to expand the monitoring distance d, only the intermediate frequency can be amplified or the voltage level (peak-to-peak value) can be changed to a DC voltage output. Therefore, compared with existing microwave sensors, it has the advantage of being able to further improve the false alarm rate.

[0069] Although the present invention has been described above with reference to specific embodiments and accompanying drawings, it is obvious to a person skilled in the art that various modifications and changes may be made without departing from the inventive concept and scope of the invention.

Claims

1. A microwave sensor for safety monitoring that improves the false alarm rate associated with biological signal detection, characterized in that: include: The first Doppler radar comprises a transmitter, which generates an oscillation frequency of a predetermined period by applying a voltage from an external source, amplifies the generated oscillation frequency to a predetermined level, and transmits the amplified frequency to the outside via a first transmitting antenna. as well as The second Doppler radar, consisting of a transceiver, The transceiver includes: A radar transceiver that generates an oscillation frequency of a specified period by applying an external voltage, amplifies the generated oscillation frequency to a specified level, and transmits the generated oscillation frequency to the outside via a second transmitting antenna, and transmits and receives signals transmitted from the first transmitting antenna and the second transmitting antenna via a first receiving antenna; a safety signal processing unit, which processes the intermediate frequency signal for safety monitoring transmitted from the first transmitting antenna by the first receiving antenna of the radar transceiver, converts the signal into a first DC voltage level of a predetermined magnitude, and outputs the result; a human body detection signal processing unit, which processes the Doppler intermediate frequency signal generated by the reflected wave of the detection object approaching the monitoring area and transmitted from the second transmitting antenna by the first receiving antenna of the radar transceiver, converts the signal into a second DC voltage level of a predetermined magnitude, and outputs the result; and a comparing unit that compares the first DC voltage level input from the safety signal processing unit with the second DC voltage level input from the human body detection signal processing unit and outputs a result value; The first receiving antenna receives the signal sent by the first transmitting antenna within the specified monitoring area and the signal reflected by the monitored object sent by the second transmitting antenna within the specified monitoring range, and processes the signals in the safety signal processing unit and the human detection signal processing unit respectively. The system detects the monitored object approaching, moving slightly, or in a stopped state and identifies sensor failure. The device further includes a judgment unit for judging whether the state is abnormal based on a value output after the comparison unit compares the first DC voltage level with the second DC voltage level and the first DC voltage level input from the safety signal processing unit. The judgment unit makes a judgment based on the result value input by the comparison unit. When the first DC voltage level is high and the second DC voltage level is high, it is determined that the monitored object is approaching. When the first DC voltage level is high and the second DC voltage level is low, it is determined to be a normal monitoring state. When the first DC voltage level is an intermediate level and the second DC voltage level is a high level, it is determined that the monitored object exists in the monitored area. When the first DC voltage level is an intermediate level and the second DC voltage level is a low level, it is determined to be a normal monitoring state. When the first DC voltage level is low and the second DC voltage level is high, it is determined that the monitored object has intruded. When the first DC voltage level is a low level and the second DC voltage level is a low level, it is determined that the alarm is a false alarm caused by a sensor failure.

2. The microwave sensor for safety monitoring with improved false alarm rate related to biological signal detection according to claim 1, characterized in that: The radar transceiver includes a filter for filtering the intermediate frequency signal for security monitoring and the Doppler intermediate frequency signal in a predetermined frequency band.

3. A microwave sensor for safety monitoring that improves the false alarm rate associated with biological signal detection, characterized in that: Including the first Doppler radar and the second Doppler radar, The first Doppler radar is composed of a first transceiver. The first transceiver includes: The first radar transceiver generates an oscillation frequency of a predetermined period by applying a voltage from an external source, amplifies the generated oscillation frequency to a predetermined level, and transmits the oscillation frequency to the outside via a first transmitting antenna. After the transmission from the first transmitting antenna, the first receiving antenna transmits and receives a reflected wave signal reflected by the detection object and a signal transmitted from the second transmitting antenna of the second transceiver, respectively. a first safety signal processing unit configured to process the intermediate frequency signal for safety monitoring received by the first receiving antenna of the first radar transceiver and transmitted from the second transmitting antenna of the second radar transceiver of the second transceiver, convert the signal into a first DC voltage level of a predetermined magnitude, and output the resultant signal; a first human detection signal processing unit configured to process a Doppler intermediate frequency signal generated by a reflected wave from a detection object approaching the monitoring area and transmitted from the first transmitting antenna and received by the first receiving antenna of the first radar transceiver, convert the signal into a second DC voltage level of a predetermined magnitude, and output the resultant signal; The first comparison unit compares the first DC voltage level input from the first safety signal processing unit and the second DC voltage level input from the first human body detection signal processing unit, and outputs a result value. The second Doppler radar is composed of a second transceiver. The second transceiver includes: The second radar transceiver generates an oscillation frequency of a predetermined period by applying a voltage from an external source, amplifies the generated oscillation frequency to a predetermined level, and transmits the oscillation frequency to the outside through a second transmitting antenna. After the transmission from the second transmitting antenna, the second receiving antenna transmits and receives a reflected wave signal reflected by the detection object and a signal transmitted from the first transmitting antenna of the first transceiver, respectively. a second safety signal processing unit, configured to process the safety monitoring intermediate frequency signal transmitted from the first transmitting antenna of the first transceiver and received by the second receiving antenna of the second radar transceiver, convert the signal into a third DC voltage level of a predetermined magnitude, and output the resultant voltage; a second human detection signal processing unit configured to process a Doppler intermediate frequency signal generated by a reflected wave from a detection object approaching the monitoring area and transmitted from the second transmitting antenna and received by the second receiving antenna of the second radar transceiver, convert the signal into a fourth DC voltage level of a predetermined magnitude, and output the resultant signal; The second comparing unit compares the third DC voltage level input from the second safety signal processing unit and the fourth DC voltage level input from the second human body detection signal processing unit, and outputs a result value. The first receiving antenna and the second receiving antenna receive signals respectively transmitted by the first transmitting antenna and the second transmitting antenna within the specified monitoring area over the monitoring distance d, and signals respectively reflected by the first transmitting antenna and the second transmitting antenna from the detection object within the specified monitoring area, so that the first human detection signal processing unit and the second human detection signal processing unit can respectively detect Doppler intermediate frequency signals for the detection object within the monitoring distance d within the specified monitoring area. After the first safety signal processing unit and the first human detection signal processing unit and the second safety signal processing unit and the second human detection signal processing unit respectively perform signal processing, the detection unit detects the detection object approaching, slightly moving, or in a stopped state and identifies a sensor failure. Also includes: a first determining unit for determining whether the state is abnormal based on a value outputted after the first comparing unit compares the first DC voltage level with the second DC voltage level and the first DC voltage level inputted from the first safety signal processing unit; and The second determining unit determines whether the state is abnormal based on the value output by the second comparing unit after comparing the third DC voltage level with the fourth DC voltage level and the third DC voltage level input from the second safety signal processing unit. The first judgment unit makes a judgment based on the result value input by the first comparison unit. The second judgment unit makes a judgment based on the result value input by the second comparison unit. When the first DC voltage level is high, the second DC voltage level is low, the third DC voltage level is high, and the fourth DC voltage level is low, it is determined to be a normal monitoring state. When the first DC voltage level is high, the second DC voltage level is low, the third DC voltage level is high, and the fourth DC voltage level is high, the second Doppler radar determines that the monitored object is approaching. When the first DC voltage level is high, the second DC voltage level is high, the third DC voltage level is high, and the fourth DC voltage level is low, the first Doppler radar determines that the monitored object is approaching. When the first DC voltage level to the fourth DC voltage level are all high levels, it is determined that the monitored object is approaching within the monitoring distance. When the first DC voltage level is low, the second DC voltage level is high or low, the third DC voltage level is low, and the fourth DC voltage level is high or low, it is determined that the monitored object has intruded. When the first to fourth DC voltage levels are all low levels, it is determined that the alarm is a false alarm caused by a sensor failure.

4. The microwave sensor for safety monitoring with improved false alarm rate related to biological signal detection according to claim 3, characterized in that: The first radar transceiver and the second radar transceiver each include a filter, and the filter is used to filter the intermediate frequency signal for security monitoring and the Doppler intermediate frequency signal in a specified frequency band.

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