Electronic device, method for controlling electronic device, and program

Abstract

This electronic device comprises: a transmission antenna unit having a plurality of transmission channels; a transmission signal processing unit that generates a transmission signal to be transmitted from the transmission antenna unit; and a transmission line that electrically connects the transmission antenna unit and the transmission signal processing unit. The transmission signal processing unit corrects the phase difference between the channels of signals to be transmitted over the transmission line.

Description

Electronic device, electronic device control method, and program CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Japanese Patent Application No. 2023-140490, filed on August 30, 2023, the entire disclosure of which is incorporated herein by reference.

[0002] The present disclosure relates to an electronic device, a control method for an electronic device, and a program.

[0003] For example, in fields such as the automobile industry, technologies for measuring the distance between a vehicle and a predetermined object have become increasingly important. In particular, in recent years, various RADAR (Radio Detecting and Ranging) technologies have been researched, which measure the distance between a vehicle and an object by transmitting radio waves such as millimeter waves and receiving the waves reflected by the object, such as an obstacle. The importance of such technologies for measuring distance is expected to increase in the future along with the development of technologies for assisting drivers in driving and technologies related to autonomous driving, which automates driving partially or completely.

[0004] Furthermore, various technologies that can be used for sensing using various sensors are also being researched. For example, Patent Document 1 proposes an in-vehicle device that can supply power to a sensor that detects biometric information of a user in a vehicle using radio waves. In the future, sensors based on the above-mentioned radar-like technology will not only be attached to moving objects such as automobiles, but will also be attached to various locations on various objects depending on the application.

[0005] Japanese Patent Application Laid-Open No. 2022-20270

[0006] According to one embodiment, an electronic device includes a transmitting antenna unit having a plurality of transmission channels, a transmitting signal processing unit that generates a transmission signal to be transmitted from the transmitting antenna unit, and a transmitting transmission line unit that electrically connects the transmitting antenna unit and the transmitting signal processing unit, and the transmitting signal processing unit corrects a phase difference between the channels of the signals transmitted from the transmitting transmission line unit.

[0007] A control method according to one embodiment is a control method for an electronic device comprising: a transmitting antenna unit having a plurality of transmitting channels; a transmitting signal processing unit that generates a transmitting signal to be transmitted from the transmitting antenna unit; and a transmitting transmission line unit that electrically connects the transmitting antenna unit and the transmitting signal processing unit, and includes a step of correcting a phase difference between each channel of a signal transmitted in the transmitting transmission line unit by the transmitting signal processing unit.

[0008] A program according to one embodiment causes an electronic device having a transmitting antenna unit having a plurality of transmitting channels, a transmitting signal processing unit that generates a transmitting signal to be transmitted from the transmitting antenna unit, and a transmitting transmission line unit that electrically connects the transmitting antenna unit and the transmitting signal processing unit to execute a step of correcting a phase difference between each channel of a signal transmitted in the transmitting transmission line unit by the transmitting signal processing unit.

[0009] 16 is a diagram illustrating a usage mode of an electronic device according to a comparative example of an embodiment. FIG. 17 is a functional block diagram schematically illustrating the configuration of an electronic device according to a comparative example of an embodiment. FIG. 18 is a diagram illustrating the configuration of a signal processed by an electronic device according to a comparative example of an embodiment. FIG. 19 is a diagram illustrating signal processing by an electronic device according to a comparative example of an embodiment. FIG. 19 is a diagram illustrating signal processing by an electronic device according to a comparative example of an embodiment. FIG. 19 is a diagram illustrating an example of antenna arrangement in an antenna array of an electronic device according to a comparative example of an embodiment and an operation principle. FIG. 20 is a diagram illustrating an example of antenna arrangement in an antenna array of an electronic device according to a comparative example of an embodiment. FIG. 21 is a diagram illustrating an example of external appearance of an electronic device according to a comparative example of an embodiment. FIG. 22 is a diagram illustrating an internal configuration of an electronic device according to a comparative example of an embodiment. FIG. 22 is a diagram illustrating the configuration of an electronic device according to an embodiment. FIG. 23 is a diagram illustrating an external appearance of an electronic device according to an embodiment. FIG. 24 is a Smith chart illustrating an example of operation of an electronic device according to a comparative example of an embodiment. FIG. 25 is a diagram illustrating S parameters of an electronic device according to a comparative example of an embodiment. FIG. 26 is a diagram illustrating a partially enlarged view of the graph shown in FIG. 16. FIG. 27 is a flowchart illustrating operation of an electronic device according to an embodiment. FIG. 28 is a diagram illustrating the configuration of an electronic device according to an embodiment. FIG. 29 is a diagram illustrating an electronic device according to an embodiment. FIG. 29 is a diagram illustrating an example of use of an electronic device according to an embodiment. 1A and 1B are diagrams illustrating an example of how an electronic device is used according to an embodiment;

[0010] For example, convenience can be improved by providing an electronic device that can increase the degree of freedom in implementation while achieving good detection through transmission and reception of radio waves such as millimeter waves. An object of the present disclosure is to provide an electronic device, a control method for an electronic device, and a program that can increase convenience. According to one embodiment, an electronic device, a control method for an electronic device, and a program that can increase convenience can be provided. Hereinafter, an electronic device according to one embodiment will be described with reference to the drawings.

[0011] In the present disclosure, an "electronic device" may refer to a device that is powered by electricity. Furthermore, a "user" may refer to a person (typically a human) or an animal that uses an electronic device according to an embodiment and / or a system including the electronic device. The user may include a person who monitors a target, such as a human, by using an electronic device according to an embodiment. Furthermore, a "target" may refer to a person (a monitoring target, for example, a human or an animal) that is monitored by an electronic device according to an embodiment. Furthermore, the user may include the target.

[0012] In this disclosure, a "heart beat" may refer to the beating of the heart. Furthermore, a "beat" may refer to the rhythmic contraction of the heart. Here, the heart includes human and animal hearts. Furthermore, a "heart beat" and a "heart sound" may include human and animal "heart beats" and "heart sounds."

[0013] In addition, in this disclosure, "heart rate" refers to the number of times the heart beats within a given period of time. For example, the heart rate may be the number of beats per minute. When the heart pumps blood, pulsations occur in the arteries. Therefore, the number of times the arteries beat may be referred to as the "pulse rate" or simply "pulse."

[0014] Furthermore, in the present disclosure, a "heart sound" may refer to the sound of the heart beating. That is, a heart sound may refer to the sound that occurs when the heart contracts and expands. Here, a "heart sound" may be composed of a first low, long sound resulting from ventricular muscle tension, mitral valve closure, the start of blood ejection into the arteries, and / or acceleration of blood flow, followed by a second high, short sound resulting from aortic valve closure and / or pulmonary valve closure.

[0015] In the present disclosure, heart sounds are not necessarily limited to physical sounds based on air vibrations, but may refer to the vibrations themselves caused by the heartbeat (pulsation). For example, in the present disclosure, heartbeats may imply a vibration source, and heart sounds may imply the vibrations themselves caused by the vibration source. Furthermore, in the present disclosure, heartbeats may also imply heart sounds depending on the situation.

[0016] An electronic device according to an embodiment can detect biometric information, such as the heartbeat, of a target, such as a human, present in the vicinity of the electronic device. Therefore, the electronic device according to an embodiment may be used in specific facilities used by socially active individuals, such as companies, hospitals, nursing homes, schools, sports gyms, and care facilities. For example, in a company, it is extremely important to understand and / or manage the health status of employees. Similarly, it is extremely important to understand and / or manage the health status of patients and medical professionals in a hospital, and of residents and staff in a nursing home. The electronic device according to an embodiment may be used in any facility where it is desirable to understand and / or manage the health status of a target, without being limited to the aforementioned facilities such as companies, hospitals, and nursing homes. The facility may also include, for example, a non-commercial facility such as a user's home. Furthermore, the electronic device according to an embodiment may be used not only indoors but also outdoors. For example, the electronic device according to an embodiment may be used inside a moving vehicle, such as a train, bus, or airplane, or at a station or platform. Furthermore, the electronic device according to an embodiment may be used in a moving body such as an automobile, an airplane, or a ship, a hotel, a user's home, a living room, a bathroom, a toilet, or a bedroom in the home, etc. Furthermore, the electronic device according to an embodiment may be used to measure the heart rates of cows, pigs, or other livestock or animals in a zoo, a ranch, a farm, etc.

[0017] An electronic device according to an embodiment may be used, for example, in a nursing facility or the like, to detect or monitor biological information, such as the heart rate of a subject, such as a person requiring nursing care or care. Furthermore, the electronic device according to an embodiment may issue a predetermined warning to the subject and / or another person when an abnormality is detected in the subject's biological information, such as the heart rate of the subject. Therefore, the electronic device according to an embodiment may allow the subject and / or staff at the nursing facility or the like to recognize that an abnormality is detected in the pulse of the subject, such as a person requiring nursing care or care. On the other hand, the electronic device according to an embodiment may notify the subject and / or other person when no abnormality is detected in the heart rate of the subject, such as a person requiring nursing care or care (e.g., the heart rate is recognized as normal). Therefore, the electronic device according to an embodiment may allow the subject and / or staff at the nursing facility or the like to recognize that the pulse of the subject, such as a person requiring nursing care or care, is normal. An electronic device according to one embodiment may determine the heartbeat interval (RR interval = RRI in an electrocardiogram) of a monitored person or animal, detect drowsiness or other distracted driving and estimate signs of such driving, estimate the level of alertness, estimate the level of fatigue, or identify the monitored person or animal, based on the heartbeat of the monitored person or animal.

[0018] Furthermore, the electronic device according to an embodiment may detect the pulse of animals other than humans. As an example, the electronic device according to an embodiment described below will be described as detecting the pulse of a human using a sensor based on technology such as millimeter-wave radar.

[0019] An electronic device according to an embodiment may be installed on any stationary object or any mobile object. The electronic device according to an embodiment can transmit a transmission wave to the surroundings of the electronic device from a transmission antenna. The electronic device according to an embodiment can receive a reflected wave of the transmission wave from a reception antenna. At least one of the transmission antenna and the reception antenna may be provided in the electronic device, or may be provided in, for example, a radar sensor.

[0020] Hereinafter, the electronic device according to an embodiment will be described as being stationary. The electronic device according to an embodiment may be installed in a moving body such as an automobile. The electronic device according to an embodiment may be installed in a moving body such as an automobile to detect biometric information, such as the heart rate, of a passenger in the moving body. Meanwhile, the subject (human) whose biometric information, such as pulse, is detected by the electronic device according to an embodiment may be stationary, moving, or moving while stationary. The electronic device according to an embodiment can measure the distance between the electronic device and an object in a situation where the object around the electronic device may move, similar to a typical radar sensor. The electronic device according to an embodiment can measure the distance between the electronic device and an object even when both the electronic device and the object are stationary.

[0021] Before describing an electronic device according to an embodiment, an electronic device according to a comparative example of the embodiment will be described first, and an example of object detection by the electronic device according to the comparative example of the embodiment will be described.

[0022] 1 is a diagram illustrating an example of a usage mode of an electronic device according to a comparative example of an embodiment, which illustrates an example of an electronic device having a sensor function and including a transmitting antenna and a receiving antenna according to an embodiment.

[0023] As shown in FIG. 1 , an electronic device 100 according to a comparative example of an embodiment may include a transmitter and a receiver, which will be described later. As described later, the transmitter may include a transmitter antenna array 24. The receiver may include a receiver antenna array 31. The transmitter antenna array 24 and the receiver antenna array 31 may be provided, for example, inside the housing of the electronic device 100. Specific configurations of the electronic device 100, the transmitter, and the receiver will be described later. For ease of viewing, FIG. 1 schematically illustrates a situation in which the electronic device 100 includes the transmitter antenna array 24 and the receiver antenna array 31 inside the housing. The electronic device 100 may also include at least one of the other functional units, such as at least a portion of the signal processing unit 10 ( FIG. 2 ), as appropriate. The electronic device 100 may also include at least one of the other functional units, such as at least a portion of the signal processing unit 10 ( FIG. 2 ), external to the electronic device 100. In FIG. 1 , the electronic device 100 may be moving or may be stationary.

[0024] In the example shown in FIG. 1 , the electronic device 100 is shown as including a transmitter having a transmitting antenna array 24 and a receiver having a receiving antenna array 31 inside the housing of the electronic device 100. The electronic device 100 may include, for example, multiple transmitters and / or multiple receivers. The transmitter may include a transmitting antenna array 24 consisting of multiple transmitting antennas. The receiver may include a receiving antenna array 31 consisting of multiple receiving antennas. Here, the locations at which the transmitters and / or receivers are installed in the electronic device 100 are not limited to the locations shown in FIG. 1 and may be other locations as appropriate. The number of transmitters and / or receivers may be one or more depending on various conditions (or requirements) such as the detection range and / or detection accuracy of biological information such as heart rate by the electronic device 100.

[0025] As described below, the electronic device 100 transmits electromagnetic waves as transmission waves from the transmitting antenna array 24. For example, if a predetermined object (e.g., the target 200 shown in FIG. 1 ) is present around the electronic device 100, at least a portion of the transmission waves transmitted from the electronic device 100 is reflected by the object and becomes a reflected wave. Then, by receiving such a reflected wave, for example, with the receiving antenna array 31 of the electronic device 100, the electronic device 100 can detect the object as a target.

[0026] The electronic device 100 including the transmitting antenna array 24 may typically be a RADAR (Radio Detecting and Ranging) sensor that transmits and receives radio waves. However, the electronic device 100 is not limited to a radar sensor. The electronic device 100 according to a comparative example of an embodiment may be a sensor based on, for example, LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) technology using light waves. Such sensors may be configured to include, for example, a patch antenna. Since technologies such as RADAR and LIDAR are already known, detailed descriptions thereof may be simplified or omitted as appropriate. Furthermore, the electronic device 100 according to a comparative example of an embodiment may be a sensor based on, for example, technology that detects objects by transmitting and receiving sound waves or ultrasonic waves.

[0027] The electronic device 100 shown in FIG. 1 receives, from the receiving antenna array 31, reflected waves of transmitted waves transmitted from the transmitting antenna array 24. In this way, the electronic device 100 can detect a predetermined object 200 present within a predetermined distance from the electronic device 100 as a target. For example, as shown in FIG. 1, the electronic device 100 can measure the distance L between the electronic device 100 and the predetermined object 200. The electronic device 100 can also measure the relative speed between the electronic device 100 and the predetermined object 200. Furthermore, the electronic device 100 can also measure the direction in which the reflected wave from the predetermined object 200 arrives at the electronic device 100 (the arrival direction (hereinafter also referred to as the "arrival angle θ")).

[0028] In Fig. 1, the XY plane may be, for example, a plane substantially parallel to the ground surface. In this case, the positive direction of the Z axis shown in Fig. 1 may indicate a vertically upward direction. In Fig. 1, the electronic device 100 may be disposed on a plane parallel to the XY plane. Also, in Fig. 1, the target 200 may be, for example, standing on the ground surface substantially parallel to the XY plane.

[0029] Here, the target 200 may be, for example, a human being present around the electronic device 100. The target 200 may also be a non-human living entity, such as an animal present around the electronic device 100. As described above, the target 200 may be moving, stationary, or static. In the present disclosure, the object detected by the electronic device 100 includes not only inanimate objects such as any object, but also living entities such as people, dogs, cats, horses, and other animals. The object detected by the electronic device 100 of the present disclosure may include targets detected using radar technology, including people, objects, and animals. In the present disclosure, targets may include people, objects, and animals. In the following description, it is assumed that an object such as the target 200 present around the electronic device 100 is a human being (or an animal). Hereinafter, the "target 200" may also be referred to as the "subject 200" as appropriate. In the present disclosure, the target may be the target 200 described above.

[0030] 1 , the ratio between the size of the electronic device 100 and the size of the target 200 does not necessarily represent the actual ratio. Also, in FIG. 1 , the transmitting antenna array 24 of the transmitting unit and the receiving antenna array 31 of the receiving unit are shown installed inside the housing of the electronic device 100. However, in one embodiment, the transmitting antenna array 24 of the transmitting unit and / or the receiving antenna array 31 of the receiving unit may be installed in various positions on the electronic device 100. For example, in one embodiment, the transmitting antenna array 24 of the transmitting unit and / or the receiving antenna array 31 of the receiving unit may be installed outside the housing of the electronic device 100.

[0031] In the following description, as a typical example, the transmitting antenna of the electronic device 100 will be described as transmitting radio waves in a frequency band such as millimeter waves (30 GHz or higher) or quasi-millimeter waves (e.g., around 20 GHz to 30 GHz). Alternatively, the transmitting antenna of the electronic device 100 may transmit radio waves having a frequency bandwidth of 4 GHz, such as 77 GHz to 81 GHz. Furthermore, the transmitting antenna of the electronic device 100 may transmit radio waves at a frequency higher than the millimeter wave band (e.g., 30 GHz to 300 GHz).

[0032] 2 is a functional block diagram schematically illustrating an example of the configuration of the electronic device 100 according to a comparative example of the embodiment. An example of the configuration of the electronic device 100 according to the comparative example of the embodiment will be described below.

[0033] When measuring distances and the like using millimeter-wave radar, frequency-modulated continuous-wave radar (hereinafter referred to as FMCW radar) is often used. FMCW radar generates a transmission signal by sweeping the frequency of the radio waves to be transmitted. Therefore, in a millimeter-wave FMCW radar using radio waves in the 79 GHz frequency band, for example, the frequency of the radio waves used has a frequency bandwidth of 4 GHz, such as 77 GHz to 81 GHz. Radar using the 79 GHz frequency band is characterized by a wider usable frequency bandwidth than other millimeter-wave / quasi-millimeter-wave radars, such as those using the 24 GHz, 60 GHz, and 76 GHz frequency bands. Hereinafter, such an embodiment will be described as an example.

[0034] The FMCW radar system used in the present disclosure may include a fast-chirp modulation (FCM) system that transmits chirp signals at a shorter period than normal. The signals generated by the electronic device 100 are not limited to FMCW signals. The signals generated by the electronic device 100 may be signals of various systems other than FMCW. The transmission signal sequence stored in any memory unit may differ depending on these various systems. For example, in the case of the above-mentioned FMCW radar signal, signals whose frequency increases and decreases with each time sample may be used. Since known technologies can be applied as appropriate to the above-mentioned various systems, further detailed description will be omitted.

[0035] As shown in FIG. 2 , the electronic device 100 according to the comparative example of the embodiment includes a signal processing unit 10. The signal processing unit 10 may include a signal generation processing unit 11, a received signal processing unit 12, a heartbeat extraction unit 13, and a calculation unit 14. The heartbeat extraction unit 13 may, for example, execute a process of extracting a micro-Doppler component. The heartbeat extraction unit 13 may also execute a process of extracting an envelope of the heart sounds of the subject 200. The calculation unit 14 may, for example, execute a process of calculating the heartbeat interval (RRI) of the subject 200. The calculation unit 14 may also execute a process of calculating the heartbeat of the subject 200. The calculation unit 14 may also execute a process of calculating the heart rate validity (HRV) of the subject 200. In this case, the calculation unit 14 may execute a process of performing a frequency analysis of the extracted time series data of the heartbeat interval of the subject 200. The calculation unit 14 may also execute processing to calculate the heart rate variability of the subject 200 based on frequency analysis of time-series data of heart rate intervals. The signal generation processing unit 11, the received signal processing unit 12, the heart rate extraction unit 13, and the calculation unit 14 will be described further below as appropriate. In the present disclosure, a heart sound may be, for example, a chest vibration waveform directly observed by radar, or may be chest vibration. A heart rate is the heartbeat itself. Heart rate intervals, heart rate, etc. may be calculated from the movement of the heart rate. A heart rate interval may be the time interval between one heartbeat and the next.

[0036] The electronic device 100 according to the comparative example of an embodiment includes a transmitting unit including a transmitting DAC 21, a transmitting circuit 22, a millimeter-wave transmitting circuit 23, and a transmitting antenna array 24. The electronic device 100 according to the comparative example of an embodiment includes a receiving unit including a receiving antenna array 31, a mixer 32, a receiving circuit 33, and a receiving ADC 34. The electronic device 100 according to the comparative example of an embodiment may not include at least one of the functional units shown in FIG. 2 , or may include functional units other than the functional units shown in FIG. 2 . The electronic device 100 shown in FIG. 2 may be configured using a circuit configured basically similarly to a general radar using electromagnetic waves in the millimeter-wave band or the like. Meanwhile, in the electronic device 100 according to the comparative example of an embodiment, the signal processing by the signal processing unit 10 may include processing different from that of conventional general radar.

[0037] The signal processing unit 10 included in the electronic device 100 according to the comparative example of an embodiment can control the overall operation of the electronic device 100, including the control of each functional unit constituting the electronic device 100. In particular, the signal processing unit 10 performs various processes on signals handled by the electronic device 100. The signal processing unit 10 may include at least one processor, such as a central processing unit (CPU) or a digital signal processor (DSP), to provide control and processing capabilities for executing various functions. The signal processing unit 10 may be implemented as a single processor, several processors, or individual processors. The processor may be implemented as a single integrated circuit. An integrated circuit is also called an IC (integrated circuit). The processor may be implemented as multiple integrated circuits and discrete circuits connected to each other in a communicative manner. The processor may also be implemented based on various other known technologies. In one embodiment, the signal processing unit 10 may be configured as, for example, a CPU (hardware) and a program (software) executed by the CPU. The signal processing unit 10 may include a storage unit (memory) necessary for the operation of the signal processing unit 10 as appropriate.

[0038] The signal generation processing unit 11 of the signal processing unit 10 generates a signal to be transmitted from the electronic device 100. In the electronic device 100 according to a comparative example of an embodiment, the signal generation processing unit 11 may generate a transmission signal (transmission chirp signal) such as a chirp signal. In particular, the signal generation processing unit 11 may generate a signal whose frequency changes periodically and linearly (linear chirp signal). For example, the signal generation processing unit 11 may generate a chirp signal whose frequency increases periodically and linearly from 77 GHz to 81 GHz over time. Alternatively, the signal generation processing unit 11 may generate a signal whose frequency periodically and linearly increases (up-chirp) and decreases (down-chirp) from 77 GHz to 81 GHz over time. The signal generated by the signal generation processing unit 11 may be preset in the signal processing unit 10, for example. Alternatively, the signal generated by the signal generation processing unit 11 may be stored in advance in, for example, an arbitrary storage unit in the signal processing unit 10. Since chirp signals used in technical fields such as radar are well known, a more detailed description thereof will be simplified or omitted as appropriate. The signal generated by the signal generation processing unit 11 is supplied to the transmission DAC 21. For this purpose, the signal generation processing unit 11 may be connected to the transmission DAC 21.

[0039] The transmission DAC (digital-to-analog converter) 21 has a function of converting the digital signal supplied from the signal generation processing unit 11 into an analog signal. The transmission DAC 21 may be configured to include a general digital-to-analog converter. The analog signal converted by the transmission DAC 21 is supplied to the transmission circuit 22. For this reason, the transmission DAC 21 may be connected to the transmission circuit 22.

[0040] The transmission circuit 22 has a function of converting the analog signal converted by the transmission DAC 21 into an intermediate frequency (IF) band. The transmission circuit 22 may be configured to include a general IF band transmission circuit. The signal processed by the transmission circuit 22 is supplied to the millimeter wave transmission circuit 23. For this reason, the transmission circuit 22 may be connected to the millimeter wave transmission circuit 23.

[0041] The millimeter wave transmission circuit 23 has a function of transmitting the signal processed by the transmission circuit 22 as a millimeter wave (RF wave). The millimeter wave transmission circuit 23 may be configured to include a general millimeter wave transmission circuit. For example, the millimeter wave transmission circuit 23 may be configured to include an amplifier (amplification circuit) that amplifies the power of the transmission wave (transmission signal). The signal processed by the millimeter wave transmission circuit 23 is supplied to the transmission antenna array 24. For this reason, the millimeter wave transmission circuit 23 may be connected to the transmission antenna array 24. The signal processed by the millimeter wave transmission circuit 23 is also supplied to the mixer 32. For this reason, the millimeter wave transmission circuit 23 may also be connected to the mixer 32.

[0042] The transmitting antenna array 24 is an array of multiple transmitting antennas. The configuration of the transmitting antenna array 24 is shown in a simplified form in Fig. 2. The transmitting antenna array 24 transmits the signal processed by the millimeter-wave transmitting circuit 23 to the outside of the electronic device 100. The transmitting antenna array 24 may be configured to include a transmitting antenna array used in a general millimeter-wave radar.

[0043] In this way, the electronic device 100 according to the comparative example of one embodiment is provided with a transmitting antenna (transmitting antenna array 24) and can transmit a transmitting signal (e.g., a transmitting chirp signal) as a transmitting wave from the transmitting antenna array 24.

[0044] 2 , assume that an object such as a subject 200 is present around the electronic device 100. In this case, at least a portion of the transmission waves transmitted from the transmitting antenna array 24 is reflected by the object such as the subject 200. At least a portion of the transmission waves transmitted from the transmitting antenna array 24 and reflected by the object such as the subject 200 may be reflected toward the receiving antenna array 31.

[0045] The receiving antenna array 31 receives the reflected waves, which may be at least a portion of the transmitted waves transmitted from the transmitting antenna array 24 that are reflected by an object such as the subject 200.

[0046] The receiving antenna array 31 is an array of multiple receiving antennas. FIG. 2 shows a simplified configuration of the receiving antenna array 31. The receiving antenna array 31 receives reflected waves of the transmitted waves transmitted from the transmitting antenna array 24. The receiving antenna array 31 may include a receiving antenna array used in a typical millimeter-wave radar. The receiving antenna array 31 supplies the received signals received as reflected waves to a mixer 32. For this purpose, the receiving antenna array 31 may be connected to the mixer 32. The reflected waves (received signals) received by the receiving antenna array 31 may be amplified with low noise by, for example, a low noise amplifier (LNA) before being supplied to the mixer 32. The LNA and other components are not shown in FIG. 2.

[0047] The mixer 32 converts the signal (transmission signal) processed by the millimeter-wave transmission circuit 23 and the reception signal received by the reception antenna array 31 (and further amplified with low noise by the LNA) into an intermediate frequency (IF) band. The mixer 32 may be configured to include a mixer used in a general millimeter-wave radar. The mixer 32 supplies the signal generated as a result of the combination to the reception circuit 33. For this reason, the mixer 32 may be connected to the reception circuit 33.

[0048] The receiving circuit 33 has a function of performing analog processing on the signal converted to the IF band by the mixer 32. The receiving circuit 33 may be configured to include a receiving circuit that converts to a general IF band. The signal processed by the receiving circuit 33 is supplied to the receiving ADC 34. For this reason, the receiving circuit 33 may be connected to the receiving ADC 34.

[0049] The receiving ADC (analog-to-digital converter) 34 has a function of converting the analog signal supplied from the receiving circuit 33 into a digital signal. The receiving ADC 34 may be configured to include a general analog-to-digital converter. The signal digitized by the receiving ADC 34 is supplied to the receiving signal processing unit 12 of the signal processing unit 10. For this reason, the receiving ADC 34 may be connected to the signal processing unit 10.

[0050] The reception signal processing unit 12 of the signal processing unit 10 has the function of performing various processes on the digital signal supplied from the reception ADC 34. For example, the reception signal processing unit 12 calculates the distance from the electronic device 100 to an object such as the subject 200 based on the digital signal supplied from the reception ADC 34 (distance measurement). The reception signal processing unit 12 also calculates the relative velocity of an object such as the subject 200 with respect to the electronic device 100 based on the digital signal supplied from the reception ADC 34 (speed measurement). Furthermore, the reception signal processing unit 12 calculates the azimuth angle of an object such as the subject 200 as seen from the electronic device 100 based on the digital signal supplied from the reception ADC 34 (angle measurement). Specifically, I / Q converted data may be input to the reception signal processing unit 12. By inputting such data, the reception signal processing unit 12 performs fast Fourier transforms (2D-FFT) in the range direction and the velocity direction, respectively. The received signal processing unit 12 may then suppress false alarms by removing noise points and making the probability constant through processing such as CFAR (Constant False Alarm Rate).The received signal processing unit 12 then estimates the angle of arrival for points that satisfy the CFAR criteria, thereby obtaining the position of an object such as the subject 200. Information generated as a result of measuring the distance, speed, and angle by the received signal processing unit 12 may be supplied to the heart rate extraction unit 13.

[0051] The heartbeat extraction unit 13 extracts information about the heartbeat from the information generated by the received signal processing unit 12. The heartbeat extraction unit 13 may extract micro-Doppler components from the information generated by the received signal processing unit 12 and execute processing to extract the envelope of the heart sounds. Various methods may be used for the operation of the heartbeat extraction unit 13 to extract information about the heartbeat. The information about the heartbeat extracted by the heartbeat extraction unit 13 may be supplied to the calculation unit 14.

[0052] The calculation unit 14 performs various calculation processes and / or arithmetic processes on the information related to the heartbeat supplied from the heartbeat extraction unit 13. For example, the calculation unit 14 may extract heartbeat intervals based on the information related to the heartbeat supplied from the heartbeat extraction unit 13, and perform a process of calculating the HRV by analyzing the frequency of time-series data of the heartbeat intervals (RRI). Various methods may be used for the various calculation processes and / or arithmetic processes performed by the calculation unit 14. The various information calculated and / or processed by the calculation unit 14 may be supplied to, for example, a communication interface 50. For this reason, the calculation unit 14 and / or the signal processing unit 10 may be connected to the communication interface 50. The various information calculated and / or processed by the calculation unit 14 may be supplied to a functional unit other than the communication interface 50.

[0053] The communication interface 50 includes an interface that outputs information supplied from the signal processing unit 10 to, for example, an external device 60. The communication interface 50 may output at least one of information regarding the position, velocity, and angle of an object such as the subject 200 as a signal such as a CAN (Controller Area Network). For example, at least one of information regarding the position, velocity, and angle of an object such as the subject 200 may be supplied to the external device 60 via the communication interface 50. For this reason, the communication interface 50 may be connected to the external device 60.

[0054] 2 , the electronic device 100 according to the comparative example of an embodiment may be connected to an external device 60 via a communication interface 50 in a wired or wireless manner. In one embodiment, the external device 60 may be configured to include any computer and / or any control device. Furthermore, the electronic device 100 according to the comparative example of an embodiment may be configured to include the external device 60. The external device 60 may have various configurations depending on how the information on the heartbeat and / or heart sounds detected by the electronic device 100 is used. Therefore, a detailed description of the external device 60 will be omitted.

[0055] FIG. 3 is a diagram illustrating an example of a chirp signal generated by the signal generation processing unit 11 of the signal processing unit 10. In FIG.

[0056] FIG. 3 shows the time structure of one frame when using the FCM (Fast-Chirp Modulation) method. FIG. 3 shows an example of a received signal in the FCM method. FCM is a method in which chirp signals shown as c1, c2, c3, c4, ..., cn in FIG. 3 are repeated at relatively short intervals (for example, equal to or longer than the round-trip time between the electromagnetic wave radar and the target, calculated from the maximum ranging distance). In FCM, for convenience of signal processing of the received signal, transmission and reception processing is often performed by dividing the signal into subframe units as shown in FIG. 3.

[0057] In Fig. 3, the horizontal axis represents elapsed time, and the vertical axis represents frequency. In the example shown in Fig. 3, the signal generation processing unit 11 generates linear chirp signals whose frequencies change periodically and linearly. In Fig. 3, each chirp signal is represented as c1, c2, c3, c4, ..., cn. As shown in Fig. 3, the frequency of each chirp signal increases linearly over time.

[0058] In the example shown in FIG. 3 , several chirp signals such as c1, c2, c3, c4, ..., cn are included in one subframe. That is, subframe 1 and subframe 2 shown in FIG. 3 are each composed of several chirp signals such as c1, c2, c3, c4, ..., cn. Also, in the example shown in FIG. 3 , several subframes such as subframe 1, subframe 2, ..., subframe N are included in one frame (one frame). That is, one frame shown in FIG. 3 is composed of N subframes. Also, one frame shown in FIG. 3 may be frame 1, followed by frame 2, frame 3, ..., etc. Each of these frames may be composed of N subframes, just like frame 1. Also, a frame interval of a predetermined length may be included between frames. One frame shown in FIG. 3 may be, for example, 30 to 50 milliseconds long.

[0059] In the electronic device 100 according to the comparative example of the embodiment, the signal generation processing unit 11 may generate a transmission signal as an arbitrary number of frames. Also, some chirp signals are omitted from the illustration in Fig. 3. In this manner, the relationship between time and frequency of the transmission signal generated by the signal generation processing unit 11 may be stored as various setting parameters in, for example, a storage unit of the signal processing unit 10.

[0060] In this way, the electronic device 100 according to the comparative example of an embodiment may transmit a transmission signal composed of subframes each including a plurality of chirp signals. Also, the electronic device 100 according to the comparative example of an embodiment may transmit a transmission signal composed of a frame each including a predetermined number of subframes.

[0061] Hereinafter, the electronic device 100 will be described as transmitting a transmission signal having a frame structure as shown in FIG. 3 . However, the frame structure as shown in FIG. 3 is merely an example, and for example, the number of chirp signals included in one subframe may be arbitrary. That is, in one embodiment, the signal generation processing unit 11 may generate subframes including any number (e.g., any plural number) of chirp signals. Also, the subframe structure as shown in FIG. 3 is merely an example, and for example, the number of subframes included in one frame may be arbitrary. That is, in one embodiment, the signal generation processing unit 11 may generate frames including any number (e.g., any plural number) of subframes. The signal generation processing unit 11 may generate signals of different frequencies. The signal generation processing unit 11 may generate multiple discrete signals, each having a frequency f with a different bandwidth.

[0062] Fig. 4 is a diagram showing, in another aspect, part of the subframe shown in Fig. 3. Fig. 4 shows each sample of the received signal that has received the transmitted signal shown in Fig. 3 as a result of 2D-FFT (Two Dimensional Fast Fourier Transform) processing performed by the received signal processing unit 12 (Fig. 2) of the signal processing unit 10.

[0063] As shown in Fig. 4, chirp signals c1, c2, c3, c4, ..., cn are stored in each subframe, such as subframe 1, ..., subframe N. In Fig. 4, each chirp signal c1, c2, c3, c4, ..., cn is composed of samples, each represented by a square arranged in the horizontal direction. The received signal shown in Fig. 4 is subjected to 2D-FFT, CFAR, and / or integrated signal processing of each subframe by the received signal processing unit 12 shown in Fig. 2.

[0064] FIG. 5 is a diagram showing an example of a point cloud calculated on a range-Doppler (distance-velocity) plane as a result of 2D-FFT, CFAR, and integrated signal processing of each subframe being performed in the received signal processing unit 12 shown in FIG.

[0065] In FIG. 5 , the horizontal direction represents range (distance), and the vertical direction represents velocity. The filled squares s1 in FIG. 5 represent point clouds indicating signals that exceed the CFAR threshold. The unfilled squares s2 in FIG. 5 represent bins (2D-FFT samples) without point clouds that do not exceed the CFAR threshold. The point clouds on the range-Doppler plane calculated in FIG. 5 have their azimuth from the radar calculated by direction estimation, and their position and velocity on a two-dimensional plane are calculated as point clouds indicating an object such as the subject 200. Here, the direction estimation may be calculated using a beamformer and / or a subspace method. Representative subspace method algorithms include MUSIC (MUltiple SIgnal Classification) and ESPRIT (Estimation of Signal Parameters via Rotation Invariance Technique).

[0066] FIG. 6 is a diagram showing an example of the results of the conversion of point cloud coordinates from the range-Doppler plane shown in FIG. 5 to the XY plane after the received signal processing unit 12 has performed direction estimation. The XY plane shown in FIG. 6 may be the same as the XY plane shown in FIG. 1. As shown in FIG. 6, the received signal processing unit 12 can plot a point cloud PG on the XY plane. Here, the point cloud PG is made up of individual points P. Furthermore, each point P has an angle θ and a radial velocity Vr in polar coordinates.

[0067] The received signal processing unit 12 detects an object present within the range in which the transmitted wave is transmitted based on at least one of the results of the 2D-FFT and the angle estimation. The received signal processing unit 12 may perform object detection by, for example, performing clustering processing based on the estimated distance information, velocity information, and angle information. Known algorithms used for clustering data include DBSCAN (Density-based spatial clustering of applications with noise). This is an algorithm that performs clustering based on density. In the clustering processing, for example, the average power of the points constituting the detected object may be calculated. The distance information, velocity information, angle information, and power information of the object detected by the received signal processing unit 12 may be supplied to an external device 60, for example, via a communication interface 50.

[0068] As described above, the electronic device 100 may include a transmitting antenna (transmitting antenna array 24), a receiving antenna (receiving antenna array 31), and a signal processing unit 10. The transmitting antenna array 24 transmits a transmission wave, for example, an electric wave. The receiving antenna array 31 receives a reflected wave of the transmission wave. The signal processing unit 10 then detects an object (such as the subject 200) that reflects the transmission wave based on the transmission signal transmitted as the transmission wave and the reception signal received as the reflected wave.

[0069] Next, estimation of the direction of an incoming wave (an incoming reflected wave) by the antenna array of the electronic device 100 according to the comparative example of the embodiment will be further described.

[0070] 7 is a diagram illustrating the configuration of the receiving antenna array 31 of the electronic device 100 according to a comparative example of the embodiment, and the principle of estimating the direction of an incoming wave by the receiving antenna array 31. FIG. 7 shows an example of reception of radio waves by the receiving antenna array 31.

[0071] As shown in Figure 7, the receive antenna array 31 may be a linear arrangement of sensors such as receive antennas. As shown in Figure 7, in one embodiment, the receive antenna array 31 may include multiple receive antennas arranged in a linear arrangement. In Figure 7, the receive antenna array 31 includes antenna x １ , x ２ , x ３ , …, x Ｍ The receiving antenna array 31 may be composed of any number of antennas. As shown in FIG. 7, the multiple antennas constituting the receiving antenna array 31 are arranged at an interval of an array pitch d. A sensor array in which sensors (antennas, ultrasonic vibrators, microphones, etc.) corresponding to various physical waves are arranged in an array is also called a Uniform Linear Array (ULA). As shown in FIG. 7, physical waves (electromagnetic waves, sound waves, etc.) are transmitted along a direction, for example, θ １ and θ ２ where θ １ and θ ２ may be the angle of arrival described above. In this way, a sensor array such as the receiving antenna array 31 can estimate the direction of arrival (angle of arrival) by utilizing the phase difference that occurs in the measurements between sensors depending on the direction of arrival of the physical wave. This method of estimating the direction of arrival of a wave is also referred to as angle of arrival estimation or direction of arrival (DoA).

[0072] In the electronic device 100 according to the comparative example of an embodiment, at least one of the transmitting antenna array 24 and the receiving antenna array 31 may be configured with multiple antennas arranged in a linear fashion. This allows, for example, millimeter-wave radar to appropriately narrow the directivity when transmitting and receiving radio waves. When transmitting a transmitted wave, the direction of the transmitted beam is often controlled by a beamformer. On the other hand, when receiving a reflected wave, the direction of arrival of the reflected wave is often estimated by a subspace method (such as the above-mentioned MUSIC and ESPRIT) rather than a beamformer. In the beamformer and subspace method, in a ULA such as that shown in FIG. 7 , a phase difference occurs in the measurements between sensors depending on the direction of arrival of electromagnetic waves arriving from various directions. Therefore, the phase difference can be used to estimate the direction of arrival of the reflected wave.

[0073] Next, the estimation of angles of the incoming waves in two directions by the antenna array of the electronic device 100 according to the comparative example of the embodiment will be further described.

[0074] FIG. 8 is a diagram showing an example of an antenna arrangement for estimating the directions of arrival at two orthogonal angles.

[0075] As shown in FIG. 8, in an electronic device 100 according to a comparative example of an embodiment, the transmitting antenna array 24 and / or the receiving antenna array 31 may be configured to include an array of a plurality of patch antenna units.

[0076] In the transmitting antenna array 24 shown in Fig. 8, one patch antenna unit may be configured to include a plurality of elements electrically connected in the direction 1 shown in the figure. In each patch antenna unit, the plurality of elements may be electrically connected by wiring such as a strip line on a substrate. In each patch antenna unit, the plurality of elements are spaced apart at intervals d shorter than half the wavelength λ of the transmitting wave. １，ｔ 8, each patch antenna unit may have any number of elements greater than or equal to two electrically connected together.

[0077] 8, the transmitting antenna array 24 may be configured by arranging a plurality of patch antenna units in a direction 2 shown in the figure. The patch antenna units are spaced apart at intervals d, which are shorter than half the wavelength λ of the transmitting wave. ２，ｔ In one embodiment, the transmit antenna array 24 may include any number of patch antenna units greater than or equal to two.

[0078] As shown in Fig. 8, in one embodiment, the receiving antenna array 31 may be configured by changing the arrangement of the multiple elements in the transmitting antenna array 24. That is, in the receiving antenna array 31 shown in Fig. 8, one patch antenna unit may be configured to include multiple elements electrically connected in the direction 2 shown in the figure. In each patch antenna unit, the multiple elements may be electrically connected by wiring such as a stripline on a substrate. In each patch antenna unit, the multiple elements are spaced apart at intervals d shorter than half the wavelength λ of the transmission wave. ２，ｓ 8, each patch antenna unit may have any number of elements greater than or equal to two electrically connected together.

[0079] 8, the receiving antenna array 31 may be configured by arranging a plurality of patch antenna units in a direction 1 shown in the figure. The patch antenna units are spaced apart at intervals d, which are shorter than half the wavelength λ of the transmission wave. １，ｓ In one embodiment, the receive antenna array 31 may include any number of patch antenna units greater than or equal to two.

[0080] The elements included in the transmitting antenna array 24 and the receiving antenna array 31 may all be arranged on the same plane (for example, on the surface layer of the same substrate). The transmitting antenna array 24 and the receiving antenna array 31 may also be arranged close to each other (monostatically). Furthermore, directions 1 and 2 shown in FIG. 8 may be geometrically orthogonal to each other.

[0081] The transmitting antenna array 24 and the receiving antenna array 31 shown in FIG. 8 can appropriately narrow the directivity of each of the transmitting antennas and the receiving antennas. Furthermore, by using the transmitting antenna array 24 shown in FIG. 8 to control the direction of transmission of each transmission wave (transmission signal) at each timing of transmission, a beamformer for direction 2 shown in FIG. 8 can be realized. Furthermore, by using the receiving antenna array 31 shown in FIG. 8, the arrival direction of the reflected wave can be estimated for direction 1 shown in FIG. 8. In this way, it is possible to estimate the arrival direction of the reflected wave for two angles that are substantially orthogonal. Therefore, it is possible to obtain a point cloud representing an object such as the subject 200 in three dimensions.

[0082] FIG. 9 is a diagram illustrating an example of the appearance of an electronic device 100 according to a comparative example of the embodiment.

[0083] 9 , an electronic device 100 according to a comparative example of an embodiment may include a housing 110. The housing 110 may be made of, for example, a resin such as plastic, or a metal. The housing 110 may have a function of protecting the internal structure of the electronic device 100. At least a portion of the housing 110 may be configured as a radome section 120. At least a portion of the radome section 120 may be configured from a material that transmits a transmission wave transmitted from the electronic device 100 and transmits a received wave (reflected wave) received by the electronic device 100.

[0084] FIG. 10 is a diagram illustrating an example of the internal structure of the housing of the electronic device 100 according to a comparative example of the embodiment.

[0085] As shown in FIG. 10 , the electronic device 100 according to the comparative example of the embodiment may include a substrate 130 as its internal structure. For example, the transmitting antenna array 24, the receiving antenna array 31, and the signal processing unit 10 may be arranged on the substrate 130. For example, the transmitting DAC 21, the transmitting circuit 22, and the millimeter-wave transmitting circuit 23 shown in FIG. 2 may also be arranged on the substrate 130 as appropriate. For example, the mixer 32, the receiving circuit 33, and the receiving ADC 34 shown in FIG. 2 may also be arranged on the substrate 130 as appropriate. Furthermore, the substrate 130 may also be arranged with an amplifier (amplifying circuit) that amplifies the power of the transmitting wave (transmitting signal) and / or a low-noise amplifier (LNA) that amplifies the reflected wave (receiving signal) received by the receiving antenna array 31, as described above.

[0086] For example, in the electronic device 100, the transmit DAC 21, the transmit circuit 22, the millimeter-wave transmit circuit 23, the mixer 32, the receive circuit 33, the receive ADC 34, and most of the signal processing unit 10 may be arranged on the substrate 130. In this case, these functional units may be implemented in a radar circuit unit (system on chip (SoC)) centered around a monolithic microwave integrated circuit (MMIC). The above-mentioned MMIC / SoC may be implemented as the signal processing unit 10 on the substrate 130 shown in FIG. 10, for example. The MMIC / SoC and the transmit antenna array 24 and receive antenna array 31 arranged on the substrate 130 may be connected through interlayer vias, microstrip lines, coplanar lines, or the like of a multilayer substrate.

[0087] FIG. 10 illustrates an antenna for four transmit and receive channels. In the exemplary configuration shown in FIG. 10 , the MMIC / SoC, the transmit antenna array 24, and the receive antenna array 31 are mounted on a substrate 130. In this case, the substrate 130 may be integrally housed in the housing 110 together with a heat dissipation mechanism and / or mechanical components for ensuring rigidity. In the present disclosure, a transmit antenna or a receive antenna channel may refer to an antenna consisting of one or more antenna elements that transmit transmit signals or receive receive signals. For example, if there are n transmit antennas each consisting of m transmit antenna elements, where m and n are any integers, this may be referred to as an n-channel transmit antenna. Also, if there are n receive antennas each consisting of m receive antenna elements, where m and n are any integers, this may be referred to as an n-channel receive antenna.

[0088] The electronic device 100 according to the comparative example of the embodiment described above may have the following concerns.

[0089] When detecting biometric information such as a user's heart rate by transmitting and receiving radio waves, it is necessary to use a sufficient number of transmitting and receiving antennas to control the directivity of the transmitted waves and / or to perform direction estimation processing of the received waves. In such cases, it is desirable to use antennas with four or more channels for both transmission and reception. However, it is not necessarily easy to integrate the transmitting antenna array 24 and the receiving antenna array 31 with the signal processing unit 10 including the MMIC / SoC to reduce the overall size.

[0090] Generally, in order to sufficiently and appropriately execute the processing of the radar sensor as shown in Fig. 10, the processor such as a CPU / DSP mounted on the circuit unit (signal processing unit 10) such as an SoC tends to generate a large amount of heat. For this reason, it is expected that the electronic device 100 according to the comparative example of the embodiment will have to have an increased size for example, a heat dissipation mechanism.

[0091] Considering the above-mentioned concerns, it is expected that an integrated configuration such as the housing 110 shown in FIG. 9 may not be suitable for cases where implementation in a small space is required, such as when sensing a user's vital signs inside a car cabin.

[0092] Furthermore, with the radar sensor configuration shown in FIG. 10 , there is a concern that the area detectable by a single MMIC / SoC (signal processing unit 10) is limited. For example, consider a case where a millimeter-wave radar is used to detect micro-Doppler to detect chest vibrations associated with a user's heartbeat or minute vibrations of other machinery or buildings. In this case, a certain angular range (e.g., approximately ±30°) in front of the millimeter-wave sensor becomes the radar's field of view (FOV). Therefore, using a single MMIC / SoC (signal processing unit 10) poses the problem of only being able to detect a specific, narrow area.

[0093] Therefore, the applicant has conducted various research and demonstration experiments and has come up with an electronic device according to an embodiment that can address the above-mentioned problems. Next, such an electronic device according to an embodiment will be described.

[0094] 11 is a diagram illustrating a schematic structure of an electronic device according to an embodiment. In the electronic device 1 according to the embodiment shown in FIG. 11, descriptions of functional units that are the same as or similar to those of the electronic device 100 according to a comparative example of the embodiment will be simplified or omitted as appropriate.

[0095] As shown in FIG. 11 , the electronic device 1 according to an embodiment may include multiple antenna units, such as Ant-1 and Ant-2. The electronic device 1 may also include a circuit unit 400 including a substrate 140. The circuit unit 400 may include a signal processing unit 10. In FIG. 11 , the electronic device 1 according to an embodiment includes two antenna units, Ant-1 and Ant-2. The electronic device 1 according to an embodiment may include at least one antenna unit Ant, or any number of antenna units. On the other hand, as described below, the electronic device 1 according to an embodiment may also include only one antenna unit, such as only Ant-1.

[0096] The antenna unit Ant-1 may have an antenna array pattern (antenna pattern) as shown in FIG. 11 . The antenna unit Ant-1 may be, for example, a rigid substrate antenna or a flexible antenna connected by a microstrip line or a coplanar line mounted on a flexible substrate. The antenna unit Ant-1 may have a transmitting antenna array 24 and a receiving antenna array 31. As shown in FIG. 11 , the antenna unit Ant-1 may have a plurality of transmitting antenna arrays 24 and a plurality of receiving antenna arrays 31. In FIG. 11 , the antenna unit Ant-1 has four transmitting antenna arrays 24 and four receiving antenna arrays 31. However, the antenna unit Ant-1 may have any number of transmitting antenna arrays 24 and any number of receiving antenna arrays 31.

[0097] The transmitting antenna array 24 and the receiving antenna array 31 are each electrically connected to an RF switch 333 via a transmission line section 332. The transmitting antenna array 24 may be electrically connected to the transmission line section 332. The receiving antenna array 31 may be electrically connected to the transmission line section 332 via an LNA (Low Noise Amplifier) ​​331. That is, the signal received by the receiving antenna array 31 may be a low-noise amplifier that amplifies the received radio waves with low noise. When amplifying the received signal, a low-noise amplifier located near the receiving antenna provides a better S / N ratio. Therefore, the LNA 331 may be connected near the receiving antenna array 31. The signal may be amplified with low noise by the LNA 331 and then supplied to the transmission line section 332. The electronic device 1 may also include an amplifier that amplifies the transmission signal at any position before the transmission signal is transmitted from the transmitting antenna array 24. The RF switch 333 connected to the transmission line unit 332 may be connected to the signal processing unit 10. The signal processing unit 10 may be implemented with the above-mentioned MMIC / SoC.

[0098] As shown in FIG. 11, the transmission line portion 332 connected to the antenna portion Ant-1 has a length L １The length of the transmission line portion 332 connected to the antenna portion Ant-1 may be set appropriately (for example, several centimeters to several meters) depending on the application of the electronic device 1, etc.

[0099] Furthermore, antenna unit Ant-2 may have the same configuration as antenna unit Ant-1. Like antenna unit Ant-1, antenna unit Ant-2 may also be connected to the signal processing unit 10 via the RF switch 333. When an antenna unit Ant other than antenna unit Ant-1 and antenna unit Ant-2 is provided, the other antenna unit Ant may also have the same configuration as antenna unit Ant-1 and antenna unit Ant-2.

[0100] The antenna unit Ant-1, the antenna unit Ant-2, etc. may include a transmitting / receiving antenna pattern corresponding to each antenna set. The antenna unit Ant-1, the antenna unit Ant-2, etc. may be mounted on a rigid dielectric substrate or a ceramic substrate, or a flexible dielectric substrate.

[0101] As shown in FIG. 11, the transmission line portion 332 connected to the antenna portion Ant-2 has a length L ２ The length of the transmission line portion 332 connected to the antenna portion Ant-2 may be set appropriately (for example, several centimeters to several meters) depending on the application of the electronic device 1, etc.

[0102] The transmission line portion 332 may be any of various components for guiding radio waves to the respective transmitting and receiving antenna sets. For example, the transmission line portion 332 may be configured by a coaxial cable or a flexible cable. Alternatively, the transmission line portion 332 may be, for example, a microstrip line or a coplanar line mounted on a flexible dielectric substrate.

[0103] The transmission line section 332 may be wired to have the same length as much as possible in all antenna channels when implemented as hardware.

[0104] The RF switch 333 may have a function of switching between the multiple transmit antenna arrays 24 and the receive antenna array 31. The RF switch 333 may be a high-frequency switch such as a single-pole double-throw (SPDT) or single-pole n-throw (SPnT, where n is a natural number greater than or equal to 2). In one embodiment, the RF switch 333 may be mounted on, for example, the substrate 140 included in the circuit unit 400. The number of RF switches 333 depends on the value of n in the case of a single-pole n-throw (SPnT, where n is a natural number greater than or equal to 2), the number Sn of transmit antenna arrays 24 for each channel, and the number Rn of receive antenna arrays 31. For example, when n = 2, Sn = 2, and Rn = 2, there may be two RF switches 333. The RF switch 333 may also be a p-pole q-throw switch, where p and q are integers. In the case shown in FIG. 11 , Sn=4 and Rn=4, so the number of single-pole double-throw (SPDT) RF switches 333 is eight in total: four for the transmitting antenna array 24 and four for the receiving antenna array 31.

[0105] As shown in FIG. 11 , in the electronic device 1, a waveguide formed by a transmission line unit 332 extends from the signal processing unit 10 to an antenna unit Ant-1, etc. FIG. 11 conceptually illustrates a waveguide 40A and a waveguide 40B extending from the signal processing unit 10 to an RF switch 333. Each waveguide extended by the transmission line unit 332 is provided with an RF switch 333. The RF switch 333 may be a single-pole-double-throw (SPDT) or single-pole-n-throw (SPnT) switch depending on the number of sets of transmitting and receiving antennas to be connected. FIG. 11 shows an example in which the RF switch 333 connects two sets of transmitting and receiving antennas.

[0106] Fig. 12 is a diagram schematically showing an example of the appearance of the electronic device 1 shown in Fig. 11. Fig. 12 shows a state in which the configuration shown in Fig. 11 is housed in, for example, a housing.

[0107] When implemented as hardware, the electronic device 1 may include a circuit section 400 and antenna sections Ant-1 and Ant-2, etc., that are separated from the circuit section 400, as shown in FIG. 12. The circuit section 400 and the antenna sections Ant-1 and Ant-2, etc., may be electrically connected to each other by a transmission line section 332. The circuit section 400 may include, for example, the signal processing section 10 (and the substrate 140) shown in FIG. 12. In FIG. 12, the transmission line section 332 may be a coaxial cable. The transmission line section 332 may also be a flexible cable or other wiring.

[0108] 12, the electronic device 1 may include a plurality of antenna units, such as antenna unit Ant-1 and antenna unit Ant-2, etc. Therefore, the electronic device 1 can have a plurality of antenna units, such as antenna unit Ant-1 and antenna unit Ant-2, mounted in different locations.

[0109] With this configuration, the electronic device 1 can suitably sense the heart rate, breathing, body movements, etc. of a human being, even when compactness is required for the implementation of a radar sensor, etc. For example, when the electronic device 1 shown in FIG. 12 is applied to an environment such as the interior of an automobile, the electronic device 1 can sense, for example, the driver's heart rate, breathing, body movements, etc. In this case, the circuit unit 400 of the electronic device 1 may be implemented, for example, near the automobile's onboard ECU. Furthermore, the antenna unit Ant-1 of the electronic device 1 may be implemented in front of the steering wheel of the automobile. Furthermore, the antenna unit Ant-2 of the electronic device 1 may be implemented near the automobile's rearview mirror.

[0110] By implementing the electronic device 1 in this manner, it is possible to robustly detect the driver's biometric information, etc., even if the driver's body position moves, and it is also possible to implement the electronic device in a space-saving manner.

[0111] Next, the operation of the electronic device 1 according to the embodiment will be described.

[0112] 11 and 12 , the electronic device 1 according to an embodiment may perform various correction operations, for example, by digital processing. The various correction operations performed by the electronic device 1 according to an embodiment will be further described below.

[0113] 11 and 12 , in the electronic device 1 according to an embodiment, the antenna units Ant-1 and Ant-2 are extended by the transmission line unit 332. When the electrical length over which radio waves are transmitted and received by the transmission line is extended in this manner, the range (distance measurement) detected by the radar sensor shifts toward the longer distance side by the amount of the extended electrical length. Therefore, the electronic device 1 according to an embodiment may perform a correction taking into account the electrical length of transmission and reception extended by the transmission line unit 332.

[0114] Generally, electromagnetic waves propagating through an axial cable, a microstrip line, a coplanar line, or the like are subject to wavelength shortening due to the dielectric of the cable. For example, when the transmission line portion 332 is a coaxial cable, the length of the coaxial cable is L [m], and the real part of the relative dielectric constant of the dielectric is ε'. ｒ Then, the wavelength shortening due to the dielectric can be expressed as the following equation (1).

[0115]

[0116] Therefore, in the electronic device 1, when the electrical length of transmission and reception extended by the transmission line portion 332 is taken into consideration, the radio wave is equivalent to having propagated a distance of L' [m] shown in the above formula (1). In this way, the length of the wiring from device to device in an electronic circuit expressed based on the signal delay time rather than the physical length (physical length) is sometimes called the electrical length.

[0117] The above-described correction needs to be performed on the values ​​when performing a distance (Range) FFT when, for example, 2D-FFT is performed in the signal processing unit 10 shown in Fig. 2. That is, if the range resolution of the 2D-FFT is d [m] and the calculated value of the Range bin of the 2D-FFT is r, the correction value r' can be expressed as in the following equation (2).

[0118]

[0119] In the above formula (2), "round" is a function that represents the rounding process of the decimal point. The numerator of the fraction in parentheses of the round function in the above formula (2) is multiplied by 2 as a coefficient. This takes into account that the transmission line sections for transmission and reception are of equal length and the round-trip paths.

[0120] (2. Correction Taking into Account Phase Between Channels) When the transmission line unit 332 is extended using a relatively long cable, a phase delay difference occurs between the channels by design, regardless of how all the channels are wired to equal lengths. This can cause deviations in direction of arrival (DOA). Therefore, the electronic device 1 according to one embodiment may correct such deviations.

[0121] (3. Correction Taking Electromagnetic Wave Loss into Account) When the transmission line unit 332 is extended, the electromagnetic wave loss seen from the final stage of the transmission / reception circuit of the electronic device 1 changes compared to when the transmission line unit 332 is not extended. This can cause a deviation from the loss in the radar equation. If such a deviation occurs, correction may be necessary, for example, when performing signal processing that takes into account the radar cross-section (RCS) of a person. Therefore, the electronic device 1 according to one embodiment may perform such a correction.

[0122] The above-mentioned "2. Correction taking into account the phase between channels" and "3. Correction taking into account the loss of electromagnetic waves" will be further explained below.

[0123] For example, in the electronic device 1 according to one embodiment, the antenna units Ant-1 and Ant-2 are each provided with a transmission line unit 332, and the line lengths thereof are slightly different. For example, one of the transmission line units 332 extending the antenna unit Ant-1 and the transmission line unit 332 extending the antenna unit Ant-2 is 60 cm and the other is 61 cm. In the electronic device 1 according to one embodiment configured in this manner, the amplitude and phase between the antenna patches in the antenna unit Ant of each channel and the signal processing unit 10 (MMIC) will be examined.

[0124] FIG. 13 shows the S-parameter (Scattering parameter) S in a configuration that does not include the transmission line portion 332, such as the electronic device 100 according to the comparative example of the embodiment shown in FIG. １１ 13 is a diagram showing an example of a Smith chart of S from 60 GHz to 67 GHz. １１ 1 shows a Smith chart of

[0125] FIG. 14 shows the S-parameter (Scattering parameter) S in a configuration including a transmission line portion 332, such as the electronic device 1 according to the embodiment shown in FIG. 11. １１ FIG. 14 shows an example of a Smith chart of S from 60 GHz to 67 GHz. １１ 14 shows a Smith chart of the S. Here, one of the transmission line portion 332 for extending the antenna portion Ant-1 and the transmission line portion 332 for extending the antenna portion Ant-2 is 60 cm and the other is 61 cm. Also, the transmission line portion 332 is a coaxial cable with an outer conductor radius of 2.6 mm, an inner conductor radius of 0.7 mm, and a dielectric layer made of polyethylene. In FIG. 14, the S. １１ and S in the 61 cm transmission line section 332 １１ It shows that:

[0126] As can be seen from a comparison between FIGS. 13 and 14, when the electronic device 1 according to the embodiment has a transmission line portion 332, the phase rotates many times on the Smith chart (FIG. 14).

[0127] Next, the state of the amplitude and phase between the antenna patches of one channel and the signal processing unit 10 (MMIC) will be shown.

[0128] 15A and 15B show the S in a configuration that does not have the transmission line portion 332, such as the electronic device 100 according to the comparative example of the embodiment shown in FIG. 10. １１ 15(a) shows the frequency change of amplitude (unit: dB), and FIG. 15(b) shows the frequency change of phase (unit: degrees). １１ In the electronic device 100 according to the comparative example of the embodiment, the antenna for channel 1 is designed to resonate at 61.5 GHz. As shown in FIG. 15A, the resonance at 61.5 GHz can be confirmed.

[0129] 16(a) and 16(b) show the S in a configuration having a transmission line portion 332, such as the electronic device 1 according to the embodiment shown in FIG. １１ 16(a) shows an example of the transmission loss and phase delay of S. FIG. 16(a) shows the frequency change of amplitude (unit: dB). FIG. 16(b) shows the frequency change of phase (unit: degree). FIG. 16(a) and FIG. 16(b) show the frequency change of S. １１ 16(a) and 16(b) show the S １１ and S in the 61 cm transmission line section 332 １１ It shows that:

[0130] Figures 17(a) and 17(b) are partial enlargements of Figures 16(a) and 16(b), respectively. More specifically, Figures 17(a) and 17(b) show the amplitude and phase of the 62 GHz to 62.2 GHz range (200 MHz span) in Figures 16(a) and 16(b), respectively.

[0131] As shown in Figures 16(a) and 16(b), S １１15(a) and 15(b), although there is no significant difference in the amplitude and phase from a general perspective, small fluctuations do occur. Furthermore, as can be seen from Figures 17(a) and 17(b), even a difference of just 1 cm in the line length of the transmission line portion 332, such as between 60 cm and 61 cm, results in changes in both the amplitude and phase. As can be seen from Figures 17(a) and 17(b), it can be seen that a difference of about 0.5 dB in amplitude and a difference of about 100 degrees occurs for a line length of 1 cm in the transmission line portion 332.

[0132] To correct for the above-described changes, the electronic device 1 according to an embodiment may determine a certain reference channel and measure the phase difference between that channel and other channels using a network analyzer, etc. By using such measurements, the electronic device 1 according to an embodiment can correct the above-described amplitude difference and / or phase difference.

[0133] More specifically, the signal processing unit 10 of the electronic device 1 according to the embodiment may first set the number of transmission channels for measurement data to N ｔ Let the number of receiving channels of measurement data be N ｒ Then, the signal processing unit 10 may correct the amplitude and phase of the radio waves transmitted and received by each channel using the first channel as a reference. After receiving a reflected wave from a transmitted wave, the signal processing unit 10 may perform the above-described amplitude and phase correction as a process before performing processing such as 2D-FFT.

[0134] Here, the signal processing unit 10 calculates the amplitude correction value Δa for the i-th receiving channel. ｉ ｒ and the phase correction value is Δφ ｉ ｒ Furthermore, the signal processing unit 10 calculates the amplitude correction value Δa for the j-th transmission channel. ｊ ｔ and the phase correction value is Δφ ｊ ｔ In one embodiment, the signal processing unit 10 may store these correction values ​​in, for example, an arbitrary memory.

[0135] Then, the signal processing unit 10 calculates the amplitude a of the actual received signal. ｉ ｒ and phase φ ｉ ｒ , and the amplitude a of the actual transmitted signal ｊ ｔｒ and phase φ ｊ ｔ In this way, the signal processing unit 10 calculates the corrected i-th received signal vector s ｉ ｒ , and the corrected j-th transmitted signal vector s ｊ ｔ In the formulas (3) and (4), i is a number from 2 onwards, and j is a number from 2 onwards.

[0136]

[0137] A specific processing method using the above formulas (3) and (4) will be further explained.

[0138] An example of the amplitude and phase difference at the transmitting and receiving ends of the transmitting antenna array 24 and the receiving antenna array 31 of the antenna unit Ant is as shown in Fig. 17. Meanwhile, the correction using the above formulas (3) and (4) may be performed by digital signal processing in, for example, the signal processing unit 10. When this correction is applied to, for example, heartbeat detection (estimation) processing, after a reflected wave from a transmitted wave is received, amplitude correction and phase correction of the received signal may be performed before basic radar processing such as 2D-FFT processing, CFAR processing, and DoA processing.

[0139] In one embodiment, the signal processing unit 10 may correct the amplitude and phase of the antenna that transmits and receives radio waves in the antenna unit Ant, based on a certain channel. In this case, the signal processing unit 10 may correct the amplitude and phase of the sensor system of the designed or actually manufactured electronic device 1, based on the S １１ The amplitude and phase difference of the signals are measured.

[0140] In this way, the signal processing unit 10 calculates the amplitude correction value Δaｉ ｒ and the phase correction value Δφ ｉ ｒ , and the amplitude correction value Δa in the j-th transmission channel ｊ ｔ and the phase correction value Δφ ｊ ｔ Therefore, the signal processing unit 10 can perform correction in accordance with the above formulas (3) and (4). These correction values, i.e., Δa ｉ ｒ , Δφ ｉ ｒ , Δa ｊ ｔ , and Δφ ｊ ｔ The correction values ​​may be stored in advance in a memory on the radar SoC. The signal processing unit 10 may read out the correction values ​​stored in the memory each time it performs radio wave transmission and reception processing.

[0141] 18 is a flowchart showing an example of the operation of estimating a heartbeat interval by the electronic device 1 according to an embodiment. Hereinafter, the operation of estimating a heartbeat interval by the electronic device 1 according to an embodiment will be outlined with reference to FIG.

[0142] Fig. 18 illustrates the operation of the electronic device 1 according to one embodiment after receiving a reflected wave. That is, as a premise for the operation illustrated in Fig. 18, the electronic device 1 illustrated in Fig. 11 transmits a transmission wave (transmission signal) from the transmitting antenna array 24. At least a portion of the transmission wave transmitted from the electronic device 1 is reflected by the subject 200 (e.g., the chest) to become a reflected wave. The electronic device 1 illustrated in Fig. 11 then receives this reflected wave from the receiving antenna array 31 and converts it into a digital signal (receiving ADC 34) (see Fig. 2). Then, the operation illustrated in Fig. 18 begins.

[0143] 18 starts, first, in step S100, the signal processing unit 10 of the electronic device 1 corrects data of each channel of a plurality of antenna units Ant, such as antenna unit Ant-1 and antenna unit Ant-2. The correction performed here may be at least one of "2. Correction taking into account the phase between channels" and "3. Correction taking into account the loss of electromagnetic waves." That is, in step S100, the signal processing unit 10 may perform amplitude correction and phase correction of the received signal. The correction performed here may also include "1. Correction taking into account the electrical length of the transmission line unit." Such a correction operation may be performed, for example, by the received signal processing unit 12 of the signal processing unit 10.

[0144] Next, in step S110, the signal processing unit 10 processes the received signal. The signal processing performed in step S110 may include, for example, the above-mentioned 2D-FFT, CFAR processing, and / or direction-of-arrival estimation. Such operations may be performed by, for example, the received signal processing unit 12 of the signal processing unit 10.

[0145] Next, in step S120, the signal processing unit 10 extracts a signal source from the information processed in step S110. The signal processing performed in step S120 may include, for example, filtering the data resulting from 2D-FFT processing. In step S120, the signal processing unit 10 may extract spectral components only at the position where the subject 200 is present. Here, the position where the subject 200 is present may be identified by various known methods. This operation may be performed, for example, by the heart rate extraction unit 13 of the signal processing unit 10.

[0146] Next, in step S130, the signal processing unit 10 converts the result of the previous processing into a vibration waveform. The processing performed in step S130 may include, for example, a process of extracting phase information from the IQ data. In step S130, the signal processing unit 10 may also include a process of extracting vibration data including heart sounds from the spectral components of the 2D-FFT processing of the subject 200 extracted in step S120. This operation may be performed, for example, by the heartbeat extraction unit 13 of the signal processing unit 10.

[0147] Next, in step S140, the signal processing unit 10 extracts vibration data from the results of the previous processing. The processing performed in step S140 may include, for example, frequency filtering. In step S140, the signal processing unit 10 may extract a low-frequency signal including an envelope of the heart sounds of the subject 200 by performing frequency filtering. This operation may be performed, for example, by the heartbeat extraction unit 13 of the signal processing unit 10.

[0148] Next, in step S150, the signal processing unit 10 detects peaks of the heartbeat of the subject 200 from the results of the previous processing, and calculates the interval between the peaks to calculate the RR interval (RRI) of the subject 200. In step S150, the signal processing unit 10 may detect peaks of a low-frequency signal including an envelope of the heart sounds of the subject 200. Also, in step S150, the signal processing unit 10 may calculate and / or extract the interval between each peak. Such an operation may be performed by, for example, the calculation unit 14 of the signal processing unit 10. As described above, in step S150, the signal processing unit 10 may extract the interval between heart sounds.

[0149] Next, in step S160, the signal processing unit 10 may calculate the heart rate variability (HRV) of the subject 200. In step S160, the signal processing unit 10 may calculate the HRV of the subject 200 by calculating the spectral density of the time-series data of the RRI. When calculating the power spectral density of the time-series data of the RRI, frequency analysis of the time-series waveform of the RRI may be performed, for example, by using Welch's method. This operation may be performed, for example, by the calculation unit 14 of the signal processing unit 10. Furthermore, in step S160, the signal processing unit 10 may analyze the spectrum from the results of the previous processing.

[0150] Thus, the electronic device 1 according to one embodiment includes an antenna unit Ant including a plurality of antenna elements, and a signal processing unit 10 that generates a transmission signal to be transmitted from the antenna unit Ant and processes a reception signal received by the antenna unit Ant. In one embodiment, the electronic device 1 includes a transmitting antenna unit Ant having a plurality of transmission channels, and a transmission signal processing unit 10 that generates a transmission signal to be transmitted from the transmitting antenna unit Ant. The electronic device 1 may also include a receiving antenna unit Ant having a plurality of reception channels, and a reception signal processing unit 10 that processes a reception signal received from the receiving antenna unit Ant.

[0151] The electronic device 1 according to an embodiment may also include a transmission line unit 332 that electrically connects the antenna unit Ant and the signal processing unit 10. Here, the signal processing unit 10 may correct a phase difference between each channel of signals transmitted and received in the transmission line unit 332. In an embodiment, the electronic device 1 may also include a transmission transmission line unit 332 that electrically connects the transmitting antenna unit Ant and the transmission signal processing unit 10. Also, the electronic device 1 may also include a reception transmission line unit 332 that electrically connects the receiving antenna unit Ant and the reception signal processing unit 10. Here, the transmission signal processing unit 10 may correct a phase difference between each channel of signals transmitted in the transmission transmission line unit 332. Also, the reception signal processing unit 10 corrects a phase difference between each channel of signals received in the reception transmission line unit 332.

[0152] In one embodiment, the substrate on which the antenna unit Ant is mounted may be separated from the substrate 140 on which the signal processing unit 10 is mounted. In this case, the substrate on which the antenna unit Ant is mounted and the substrate 140 on which the signal processing unit 10 is mounted may be connected by a transmission line unit 332. In one embodiment, the first substrate on which the transmitting antenna unit Ant or the receiving antenna unit Ant is mounted may be separated from the second substrate on which the transmitting signal processing unit 10 or the receiving signal processing unit 10 is mounted. Here, the first substrate and the second substrate may be connected by a transmitting transmission line unit 332 or a receiving transmission line unit 332.

[0153] In one embodiment, the signal processing unit 10 may detect the monitoring target based on a transmission signal transmitted as a transmission wave from the antenna unit Ant and a reception signal received by the antenna unit Ant as a reflected wave of the transmission wave reflected by the monitoring target. In one embodiment, the transmission signal processing unit 10 may detect the monitoring target based on a transmission signal transmitted as a transmission wave from the transmitting antenna unit Ant. In another embodiment, the reception signal processing unit 10 may detect the monitoring target based on a reception signal received by the receiving antenna unit Ant as a reflected wave of the transmission wave reflected by the monitoring target.

[0154] In addition, in one embodiment, the signal processing unit 10 may correct a deviation in the direction of arrival estimation caused by a phase delay difference occurring between the channels of the signals transmitted and received in the transmission line unit 332. In one embodiment, the transmission signal processing unit 10 or the reception signal processing unit 10 may correct a deviation in the direction of arrival estimation caused by a phase delay difference occurring between the transmission channels or the reception channels.

[0155] Furthermore, in one embodiment, as described above, the signal processing unit 10 may correct the amplitude of the signal detected by the signal processing unit 10 based on the loss of the signal transmitted and received in the transmission line unit 332. In one embodiment, the transmission signal processing unit 10 or the reception signal processing unit 10 may correct the amplitude of the signal detected by the transmission signal processing unit 10 or the reception signal processing unit 10 based on the loss of the signal.

[0156] In one embodiment, the signal processing unit 10 may correct the distance to the detected monitoring target based on the electrical length of the signal transmitted and received in the transmission line unit 332. In one embodiment, the transmitting signal processing unit 10 or the receiving signal processing unit 10 may correct the distance to the monitoring target based on the electrical length of the signal in the transmitting transmission line unit 332 or the receiving transmission line unit 332.

[0157] In one embodiment, the antenna unit Ant may include a first antenna unit Ant-1 and a second antenna unit Ant-2. In this case, the first transmission line unit 332 may connect the first antenna unit Ant-1 to the signal processing unit 10. In addition, the second transmission line unit 332 may connect the second antenna unit Ant-2 to the signal processing unit 10. In this case, an RF switch 333 may be provided that switches between the connection between the first antenna unit Ant-1 and the signal processing unit 10 and the connection between the second antenna unit Ant-2 and the signal processing unit 10. In one embodiment, the transmitting antenna unit Ant may include a first transmitting antenna unit Ant-1 and a second transmitting antenna unit Ant-2. In this case, the first transmitting transmission line unit 332 may connect the first transmitting antenna unit Ant-1 to the transmitting signal processing unit 10. Furthermore, the second transmitting transmission line section 332 may connect the second transmitting antenna section Ant-2 to the transmitting signal processing section 10. In this case, the electronic device 1 may include a transmitting RF switch 333 that switches between the connection between the first transmitting antenna section Ant-1 and the transmitting signal processing section 10 and the connection between the second transmitting antenna section Ant-2 and the transmitting signal processing section 10.

[0158] In one embodiment, the electronic device 1 may include two antenna units Ant (Ant-1 and Ant-2), or may include three or more antenna units Ant (Ant-1, Ant-2, and Ant-n). In one embodiment, the electronic device 1 may include two transmitting antenna units Ant, or may include three or more transmitting antenna units Ant.

[0159] Furthermore, in one embodiment, the electronic device 1 may include a low-noise amplifier LNA331 that amplifies, with low noise, a reception signal received by the reception antenna in the antenna unit Ant. In one embodiment, the electronic device 1 may include a low-noise amplifier LNA331 that amplifies, with low noise, a reception signal received by the reception antenna in the reception antenna unit Ant.

[0160] Furthermore, in one embodiment, the antenna unit Ant may be a sheet antenna formed on a flexible substrate, etc. In one embodiment, at least one of the transmitting antenna unit Ant and the receiving antenna Ant may be a sheet antenna formed on a flexible substrate.

[0161] As described above, the electronic device 1 according to an embodiment extracts components that are thought to be the envelope of the heartbeat by frequency filtering the vibrations at the position where the subject 200 is present, and determines the interval between the peaks of the envelope as the heartbeat interval. In this way, the electronic device 1 according to an embodiment can calculate the heartbeat interval of the subject 200.

[0162] For example, the electronic device 1 according to one embodiment can be installed in a vehicle such as an automobile to detect the heart rate of a passenger in the vehicle. In this case, the electronic device 1 according to one embodiment can analyze the driver's RRI by measuring the driver's heart rate using radar. If such an RRI analysis can be performed with relatively high accuracy, the electronic device 1 can be used, for example, to estimate the psychological state of a passenger, such as a driver, including the level of alertness. Furthermore, if such an RRI analysis can be performed with relatively high accuracy, the electronic device 1 can also be used, for example, to detect distracted driving, including drowsy driving, or to detect signs of such distracted driving.

[0163] As described above, the electronic device 1 according to one embodiment can measure vibrations on the body surface of a subject by applying signal processing to reflected waves (received waves) obtained from a radar. As a result, the electronic device 1 according to one embodiment can obtain a good cardiac waveform of a human or animal. Furthermore, the electronic device 1 according to one embodiment can detect the presence or absence of noise, including road noise, superimposed on the obtained cardiac waveform by multivariate analysis. Furthermore, the electronic device 1 according to one embodiment can separate heart sounds from noise when the obtained cardiac waveform contains noise.

[0164] Furthermore, the electronic device 1 according to one embodiment is expected to achieve various technical effects by implementing the antenna section Ant, which includes an antenna for transmitting and receiving radio waves, separately from the circuit section 400, which includes an MMIC / SoC.

[0165] For example, as described above, when detecting biometric information such as a user's heart rate by transmitting and receiving radio waves, it is necessary to use a sufficiently large number of transmitting and receiving antennas to control the directivity of the transmitted waves and / or to perform direction estimation processing of the received waves. In such cases, it is desirable to use antennas with four or more channels for both transmission and reception. According to the electronic device 1 of one embodiment, the transmitting antenna array 24 and the receiving antenna array 31 are integrated with the signal processing unit 10 including the MMIC / SoC, thereby enabling the overall size to be reduced.

[0166] 10 , a processor such as a CPU / DSP mounted on a circuit unit (signal processing unit 10) such as an SoC tends to generate a lot of heat. Therefore, it is expected that the electronic device 100 according to the comparative example of the embodiment will have to have a large heat dissipation mechanism, for example.

[0167] However, the electronic device 1 according to one embodiment can also be used in cases where it is required to be mounted in a small space, such as when sensing the vital signs of a user inside a vehicle.

[0168] 10, there is a concern that the area detectable by one MMIC / SoC (signal processing unit 10) is limited. However, according to the electronic device 1 according to one embodiment, even when one MMIC / SoC (signal processing unit 10) is used, it is possible to detect a relatively wide area by using multiple antenna units Ant.

[0169] As described above, the electronic device 1 according to one embodiment can realize good detection by transmitting and receiving radio waves such as millimeter waves, while increasing the degree of freedom in mounting the electronic device 1 (or the antenna unit Ant and the circuit unit 400). Therefore, according to one embodiment, it is possible to provide an electronic device that can improve convenience.

[0170] The electronic device 1 according to an embodiment can measure distance (ranging), estimate angle (angle measurement), and detect Doppler velocity (velocity measurement) by using a Doppler radar with a high frequency (20 GHz or higher) in the millimeter wave band or higher. The electronic device 1 according to an embodiment can detect vital signals, such as the heartbeat, heartbeat, breathing, or biological vibrations of a human or animal, or vibrations of a building or machine. The electronic device 1 according to an embodiment can separately mount the transmitting and receiving antennas, thereby enabling the implementation of a system such as a millimeter wave radar even in applications where space saving is required.

[0171] (Other Embodiments) Hereinafter, other embodiments will be described.

[0172] The above-described embodiment has been described assuming sensing of the heartbeat, breathing, body movement, etc. of an object such as a human body or an animal. However, sensing by the electronic device 1 according to an embodiment is not limited to the heartbeat, breathing, body movement, etc. of an object such as a human body or an animal. For example, the electronic device 1 according to an embodiment can also be used to measure general vibrations of, for example, artificial or natural objects.

[0173] 11 and 12, the electronic device 1 according to the embodiment has been described as including a plurality of antenna units Ant, such as antenna unit Ant-1 and antenna unit Ant-2, etc. However, the electronic device according to the embodiment may include only one antenna unit, such as only Ant-1.

[0174] FIG. 19 is a diagram illustrating a schematic structure of an electronic device having only one antenna unit.

[0175] As shown in Fig. 19, the electronic device 2 may include only one antenna unit Ant, for example, antenna unit Ant-1. That is, the electronic device 2 shown in Fig. 19 may include one antenna unit Ant-1 and one circuit unit 400. As shown in Fig. 19, the antenna unit Ant-1 and the circuit unit 400 may be electrically connected by a transmission line unit 332. By having only one antenna unit Ant, the electronic device 2 shown in Fig. 19 can omit the RF switch 333, such as an SPDT or SPnT, compared to the electronic device 1 shown in Fig. 11.

[0176] 12, in the electronic device 1 according to an embodiment, at least one of the antenna units Ant-1 and Ant-2 may be encased in, for example, a housing. Meanwhile, in the electronic device according to an embodiment, at least one of the one or more antenna units Ant may include, for example, an uncased, exposed antenna. Here, the exposed antenna may be an antenna made of a rigid substrate, an antenna made of a flexible substrate, or a curved antenna that is not flat.

[0177] The electronic device 1 according to the above-described embodiment may perform both amplitude correction and phase correction, or may perform either one of them. For example, if the difference in amplitude between each channel is small, the electronic device 1 may perform only phase correction and omit amplitude correction.

[0178] In the above-described embodiment, the orientation of the radiation surface of the antenna unit Ant and the orientation of any of the planar portions of the circuit unit 400 may be set in various ways.

[0179] 20 is a diagram illustrating a schematic structure of an electronic device according to a variant embodiment. In one embodiment, as in the electronic device 3 shown in FIG. 20, the normal direction of the radiation surface (surface A) of the antenna unit Ant may be different from the normal direction of the surface (surface B) of the circuit unit 400 including the SoC (for example, these normals may be perpendicular to each other). Such a configuration is expected to increase the degree of freedom in installing the antenna unit Ant.

[0180] For reference, some examples of installation modes of the electronic device 1 according to the above-described embodiment will be shown below.

[0181] FIG. 21 is a diagram illustrating a schematic example of a location where the antenna unit Ant of the electronic device 1 according to an embodiment can be installed in a mobile object 500, such as an automobile. As shown in FIG. 21 , the antenna unit Ant of the electronic device 1 according to an embodiment may be disposed in at least one of the locations marked "Ant" in the mobile object 500. Also, as shown in FIG. 21 , the circuit unit 400 of the electronic device 1 according to an embodiment may be installed in any location, such as near an ECU. Each antenna unit Ant and the circuit unit 400 may be electrically connected by a transmission line unit 332. The transmission line unit 332 connecting each antenna unit Ant and the circuit unit 400 is not shown in FIG. 21 .

[0182] 21 , the antenna unit Ant may be disposed, for example, on the surface or inside of a headrest or seat of the vehicle 500. Such an arrangement of the antenna unit Ant makes it possible to ensure sufficient space for the arrangement even in a small vehicle interior. Furthermore, with the antenna unit Ant disposed in this manner, vital signs can be detected with high accuracy in a position close to the person (passenger).

[0183] 21 , the antenna unit Ant may be arranged in two separate positions on the seat of the vehicle 500, for example, at the waist and heart of the seated person. With the antenna unit Ant arranged in this way, it is possible to perform detection while covering the difference in physique between an adult and a child passenger.

[0184] 21 , the antenna unit Ant may be disposed at various positions on the front of the vehicle 500, such as on the steering wheel, dashboard, sun visor, and / or rearview mirror of the vehicle 500. With the antenna unit Ant disposed in this manner, the chest heartbeat of the passenger can be accurately detected.

[0185] 21 , the antenna unit Ant may be disposed on the steering wheel and / or dashboard of the vehicle 500. Such an arrangement of the antenna unit Ant makes it possible to secure sufficient space for the antenna unit Ant even in a small vehicle interior. Furthermore, the antenna unit Ant disposed in this manner can detect the driver's vital signs with particularly high accuracy.

[0186] 21 , the antenna unit Ant may be disposed on the ceiling of the vehicle 500 and / or near an interior light, etc. By disposing the antenna unit Ant in this manner, it is possible to secure sufficient space for disposing the antenna unit Ant even in a small vehicle interior. Furthermore, with the antenna unit Ant disposed in this manner, it is possible to widen the detection range inside the vehicle 500.

[0187] 21 , the antenna unit Ant may be disposed on the door, floor, rear window, and / or rear of the vehicle 500. By disposing the antenna unit Ant in this manner, it is possible to ensure sufficient space for the antenna unit Ant even in a small vehicle interior.

[0188] The electronic device according to the above-described embodiment may be installed in any mobile object traveling on public roads. However, electronic devices according to other embodiments may be similarly applied not only to mobile objects traveling on public roads, such as automobiles, but also to environments where noise may be generated, such as aircraft, ships, or trains. Furthermore, electronic devices according to other embodiments may be similarly applied to noise generated by the physical movements of a subject in an indoor environment. Furthermore, an electronic device according to one embodiment may be applied to measuring the heart rate of a subject riding on a motorcycle, bus, bicycle, truck, construction vehicle, tractor, or the like.

[0189] FIG. 22 is a diagram illustrating a schematic example of a location where the antenna unit Ant of the electronic device 1 according to an embodiment can be installed in a space 600, such as a home or an office. As shown in FIG. 22 , the antenna unit Ant of the electronic device 1 according to an embodiment may be disposed in at least one of the locations marked "Ant" in the space 600. Also, as shown in FIG. 22 , the circuit unit 400 of the electronic device 1 according to an embodiment may be installed in any location, such as under the floor. Each antenna unit Ant and the circuit unit 400 may be electrically connected by a transmission line unit 332. The transmission line unit 332 connecting each antenna unit Ant and the circuit unit 400 is not shown in FIG. 22 .

[0190] 22 , the antenna unit Ant may be disposed, for example, on a door, floor, and / or wall within the space 600. With the antenna unit Ant disposed in this manner, it is possible to detect people or animals entering or leaving the space 600.

[0191] 22 , the antenna unit Ant may be disposed, for example, on the ceiling and / or inside or near a ceiling light within the space 600. With the antenna unit Ant disposed in this manner, the entire space 600 can be monitored from above.

[0192] 22 , the antenna unit Ant may be placed, for example, inside or near furniture in the space 600. The antenna unit Ant placed in this manner can also be moved within the space 600.

[0193] As shown in Fig. 22 , antenna unit Ant may be placed, for example, inside or near a bed in space 600. Also, as shown in Fig. 22 , antenna unit Ant may be placed, for example, near the ceiling facing the bed in space 600. Also, as shown in Fig. 22 , antenna unit Ant may be placed, for example, on the outer frame of the bed or near there in space 600. With antenna unit Ant placed in this manner, it is possible to constantly measure the heart rate and / or breathing of a person sleeping in bed in space 600.

[0194] As shown in FIG. 22 , the antenna unit Ant may be disposed on, for example, four wall surfaces within the space 600. In this case, the antenna unit Ant may be disposed on or inside the wall surface. The space 600 may be, for example, a living room, a bedroom, a bathroom, a toilet, or a kitchen. With the antenna unit Ant disposed in this manner, the heart rate and / or breathing of a person present within the space 600 can be constantly measured. For example, the heart rate and / or breathing of a person present within the space 600 can be constantly measured even when the person is watching television, sleeping, taking a bath, using the toilet, cooking, or the like.

[0195] FIG. 23 is a diagram illustrating a schematic example of a location where the antenna unit Ant of the electronic device 1 according to an embodiment can be installed in a space 700, such as a hospital room or a nursing home. As shown in FIG. 23 , the antenna unit Ant of the electronic device 1 according to an embodiment may be disposed in at least one of the locations marked "Ant" in the space 700. Also, as shown in FIG. 23 , the circuit unit 400 of the electronic device 1 according to an embodiment may be installed in any location, such as under the floor. Each antenna unit Ant and the circuit unit 400 may be electrically connected by a transmission line unit 332. The transmission line unit 332 connecting each antenna unit Ant and the circuit unit 400 is not shown in FIG. 23 .

[0196] As shown in Fig. 23 , antenna unit Ant may be disposed, for example, inside or near bed 710 in space 700. Also, as shown in Fig. 23 , antenna unit Ant may be disposed, for example, near the ceiling facing bed 710 in space 700. Also, as shown in Fig. 23 , antenna unit Ant may be disposed, for example, inside or near the frame (or side) of bed 710 in space 700. In this case, as shown in Fig. 23 , antenna unit Ant may be disposed, for example, near a position corresponding to the head, chest, and / or legs (or feet) of a person lying on bed 710. With antenna unit Ant disposed in this manner, vital signs can be detected more accurately according to the body position of the person lying on bed 710.

[0197] 2, the signal processing unit 10 has been described as including functional units such as the heart rate extraction unit 13 and the calculation unit 14. However, in one embodiment, the processing performed by the heart rate extraction unit 13 and / or the calculation unit 14 may be performed by an external computer or processor.

[0198] As described above, the electronic device 1 according to an embodiment detects weak vibrations such as a heartbeat using, for example, a millimeter-wave sensor including multiple transmitting antennas and multiple receiving antennas. When no target is detected, the electronic device 1 according to an embodiment detects the target's body movement while changing the beamforming pattern of the transmitting antenna by changing the antenna's transmission phase. On the other hand, when the electronic device 1 according to an embodiment detects the target's body movement, it performs beamforming in the direction of the body movement and detects the heartbeat. In this way, the electronic device 1 according to an embodiment can improve signal quality by automatically detecting the direction of the human body. Therefore, the electronic device 1 according to an embodiment can improve the heartbeat detection accuracy and / or detection range. Therefore, the electronic device 1 according to an embodiment can detect a human heartbeat with high accuracy.

[0199] While the present disclosure has been described based on various drawings and examples, it should be noted that those skilled in the art can easily make various modifications and alterations based on the present disclosure. Therefore, it should be noted that these modifications and alterations are within the scope of the present disclosure. For example, the functions included in each functional unit can be rearranged so as not to cause logical inconsistencies. Multiple functional units can be combined into one or divided. The above-described embodiments of the present disclosure are not limited to faithful implementation of each of the described embodiments, but can be implemented by combining each feature or omitting some features as appropriate. In other words, those skilled in the art can make various modifications and alterations to the contents of the present disclosure based on the present disclosure. Therefore, these modifications and alterations are within the scope of the present disclosure. For example, in each embodiment, each functional unit, each means, each step, etc. can be added to other embodiments so as not to cause logical inconsistencies, or can be replaced with each functional unit, each means, each step, etc. of other embodiments. Furthermore, in each embodiment, multiple functional units, each means, each step, etc. can be combined into one or divided into two or more. Furthermore, each of the above-described embodiments of the present disclosure is not limited to being implemented faithfully according to each of the described embodiments, but can also be implemented by combining each feature or omitting some of them as appropriate.

[0200] The above-described embodiment is not limited to implementation as the electronic device 1. For example, the above-described embodiment may be implemented as a control method for a device such as the electronic device 1. Furthermore, the above-described embodiment may be implemented as a program executed by a device such as the electronic device 1, or as a storage medium or recording medium on which a program is recorded.

[0201] DESCRIPTION OF SYMBOLS 1 Electronic device 10 Signal processing unit 11 Signal generation processing unit 12 Received signal processing unit 13 Heart rate extraction unit 14 Calculation unit 21 Transmission DAC 22 Transmission circuit 23 Millimeter wave transmission circuit 24 Transmission antenna array 31 Receiving antenna array 32 Mixer 33 Receiving circuit 34 Receiving ADC 40A, 40B Waveguide 50 Communication interface 60 External device 100 Electronic device (comparative example) 110 Housing 120 Radome unit 130 Substrate Antenna unit 140 Substrate 331 LNA 332 Transmission line unit 333 RF switch 400 Circuit unit 500 Mobile body 600 Space 700 Space 710 Bed

Claims

1. An electronic device comprising: a transmitting antenna section having a plurality of transmitting channels; a transmitting signal processing section that generates a transmitting signal to be transmitted from the transmitting antenna section; and a transmitting transmission line section that electrically connects the transmitting antenna section and the transmitting signal processing section, wherein the transmitting signal processing section corrects the phase difference between each channel of the signal transmitted in the transmitting transmission line section.

2. An electronic device as described in claim 1, comprising: a receiving antenna section having a plurality of receiving channels; a receiving signal processing section that processes a receiving signal received from the receiving antenna section; and a receiving transmission line section that electrically connects the receiving antenna section and the receiving signal processing section, wherein the receiving signal processing section corrects the phase difference between each channel of the signal received at the receiving transmission line section.

3. The electronic device according to claim 2, wherein a first board on which the transmitting antenna section or the receiving antenna section is mounted is separated from a second board on which the transmitting signal processing section or the receiving signal processing section is mounted, and the first board and the second board are connected by the transmitting transmission line section or the receiving transmission line section.

4. The electronic device according to claim 1, wherein the transmission signal processing section detects a monitoring target based on a transmission signal transmitted as a transmission wave from the transmission antenna section.

5. The electronic device according to claim 4, wherein the received signal processing section detects the monitoring target based on a received signal received by the receiving antenna section as a reflected wave of the transmitted wave reflected by the monitoring target.

6. The electronic device according to claim 2, wherein the transmission signal processing section or the reception signal processing section corrects deviations in direction-of-arrival estimation caused by phase delay differences between transmission channels or reception channels.

7. The electronic device according to claim 2, wherein the transmission signal processing section or the reception signal processing section corrects the amplitude of the signal detected by the transmission signal processing section or the reception signal processing section based on a loss of the signal.

8. The electronic device according to claim 2, wherein the transmission signal processing section or the reception signal processing section corrects the distance to the monitoring target based on the electrical length of the signal in the transmission transmission line section or the reception transmission line section.

9. The electronic device of claim 1, wherein the transmitting antenna section includes a first transmitting antenna section and a second transmitting antenna section, and is provided with a first transmitting transmission line section connecting the first transmitting antenna section and the transmitting signal processing section, a second transmitting transmission line section connecting the second transmitting antenna section and the transmitting signal processing section, and a transmitting switch for switching between the connection between the first transmitting antenna section and the transmitting signal processing section and the connection between the second transmitting antenna section and the transmitting signal processing section.

10. The electronic device according to claim 1, comprising two transmitting antenna units.

11. The electronic device according to claim 1, comprising three or more transmitting antenna units.

12. The electronic device according to claim 2, further comprising a low-noise amplifier for amplifying, with low noise, a signal received by the receiving antenna in said receiving antenna section.

13. The electronic device according to claim 2, wherein at least one of the transmitting antenna section and the receiving antenna is a sheet antenna formed on a flexible substrate.

14. A control method for an electronic device comprising: a transmitting antenna section having a plurality of transmitting channels; a transmitting signal processing section that generates a transmitting signal to be transmitted from the transmitting antenna section; and a transmitting transmission line section that electrically connects the transmitting antenna section and the transmitting signal processing section, the control method including a step of correcting a phase difference between each channel of a signal transmitted in the transmitting transmission line section by the transmitting signal processing section.

15. A program that causes an electronic device comprising a transmitting antenna section having a plurality of transmitting channels, a transmitting signal processing section that generates a transmitting signal to be transmitted from the transmitting antenna section, and a transmitting transmission line section that electrically connects the transmitting antenna section and the transmitting signal processing section to execute a step of correcting the phase difference between each channel of the signal transmitted in the transmitting transmission line section by the transmitting signal processing section.

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