Electronic device and method for designing electronic device

Abstract

To provide an electronic device capable of detecting an object with high accuracy, such as a radar device including an appropriate radome, and to provide a method of designing such an electronic device.SOLUTION: The electronic device includes a transmission antenna that transmits a transmission wave, a reception antenna that receives a reflected wave obtained by reflecting the transmission wave, a cover portion that covers at least a part of at least one of the transmission antenna and the reception antenna, and a signal processing unit that detects an object that reflects the transmission wave based on at least one of a transmission signal and a reception signal. At least a part of at least one of the transmission wave and the reflected wave is transmitted and / or received through the cover part. At least one of the shape of at least one of the cover portion and the housing of the electronic device, the number of channels of at least one of the transmission antenna and the reception antenna, the number of antenna elements constituting at least one of the transmission antenna and the reception antenna, and the distance between the antenna elements constituting at least one of the transmission antenna and the reception antenna is designed based on the square amplitude coherence.SELECTED DRAWING: Figure 1

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Japanese Patent Application No. 2022-006696, filed on January 19, 2022, the entire disclosure of which is incorporated herein by reference. [Technical Field]

[0002] The present disclosure relates to electronic devices and methods for designing electronic devices. [Background technology]

[0003] For example, in fields such as the automobile industry, technology for measuring the distance between a vehicle and a predetermined object has 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 technology for measuring distance is expected to increase in the future along with the development of technologies for assisting drivers and technologies related to autonomous driving, which automates driving partially or completely.

[0004] Various proposals have also been made regarding technologies for detecting the presence of an object by receiving reflected waves of transmitted radio waves reflected by the object. For example, Patent Document 1 proposes a device that can detect the presence of a person and their biological information by using microwaves. Also, for example, Patent Document 2 proposes a device that detects vital signs such as the frequency of a living body's breathing or heartbeat based on a reflected signal from a microwave radar. Furthermore, Patent Document 3 discloses a radar device that improves isolation between transmission and reception by providing a partition wall in a radome that prevents radio waves from leaking from the transmitting antenna unit to the receiving antenna unit. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-71825 [Patent Document 2] Patent Publication No. 2021-32880 [Patent Document 3] Japanese Patent Application Laid-Open No. 2012-93305 Summary of the Invention

[0006] An electronic device according to an embodiment includes: a transmitting antenna for transmitting a transmission wave; a receiving antenna for receiving a reflected wave of the transmitted wave; a cover portion that covers at least a portion of at least one of the transmitting antenna and the receiving antenna; a signal processing unit that detects an object that reflects the transmission wave based on at least one of a transmission signal that is transmitted as the transmission wave and a reception signal that is received as the reflected wave; Equipped with. At least a part of at least one of the transmitted wave transmitted by the transmitting antenna and the reflected wave received by the receiving antenna is transmitted and / or received via the cover portion. the shape, size, material, or structure of at least one of the cover and the housing of the electronic device; the number of channels of at least one of the transmitting antenna and the receiving antenna; The number, shape, size, material, or arrangement of antenna elements constituting at least one of the transmitting antenna and the receiving antenna; and The distance between antenna elements constituting at least one of the transmitting antenna and the receiving antenna, the connection state between the antenna elements, the number of feeding points that feed power to the antenna elements, or the distance to the feeding points that feed power to the antenna elements, at least one of which is designed based on squared amplitude coherence.

[0007] A method for designing an electronic device according to an embodiment includes: a transmitting antenna for transmitting a transmission wave; a receiving antenna for receiving a reflected wave of the transmitted wave; a cover portion that covers at least a portion of at least one of the transmitting antenna and the receiving antenna; a signal processing unit that detects an object that reflects the transmission wave based on at least one of a transmission signal that is transmitted as the transmission wave and a reception signal that is received as the reflected wave; A method for designing an electronic device comprising: At least a part of at least one of a transmission wave transmitted by the transmitting antenna and a reflected wave received by the receiving antenna is transmitted and / or received via the cover, the shape, size, material, or structure of at least one of the cover and the housing of the electronic device; the number of channels of at least one of the transmitting antenna and the receiving antenna; The number, shape, size, material, or arrangement of antenna elements constituting at least one of the transmitting antenna and the receiving antenna; and The distance between antenna elements constituting at least one of the transmitting antenna and the receiving antenna, the connection state between the antenna elements, the number of feeding points that feed power to the antenna elements, or the distance to the feeding points that feed power to the antenna elements, based on squared amplitude coherence. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view illustrating a configuration of an electronic device according to an embodiment. [Figure 2] 1 is a cross-sectional view illustrating a configuration of an electronic device according to an embodiment. [Figure 3] FIG. 1 is a block diagram illustrating a functional configuration of an electronic device according to an embodiment. [Figure 4] 1 is a flowchart illustrating a method for designing an electronic device according to an embodiment. [Figure 5] 10A and 10B are diagrams showing evaluation results of electronic devices equipped with various cover parts according to an embodiment. [Figure 6] 10A and 10B are diagrams showing evaluation results of electronic devices equipped with various cover parts according to an embodiment. [Figure 7] FIG. 2 is a block diagram showing a functional configuration of an evaluation system when designing an electronic device according to an embodiment. [Figure 8] 10A and 10B are diagrams showing evaluation results of electronic devices equipped with various cover parts according to an embodiment. [Figure 9] 10A and 10B are diagrams showing evaluation results of electronic devices equipped with various cover parts according to an embodiment. [Figure 10] 10A and 10B are diagrams showing evaluation results of electronic devices equipped with various cover parts according to an embodiment. [Figure 11] 1 is a flowchart illustrating a method for designing an electronic device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] There is a demand for electronic devices capable of detecting objects with high accuracy, such as radar devices equipped with an appropriate radome. In particular, electronic devices such as radar devices that can detect weak vibrations, such as the heartbeat of a human or animal, with high accuracy by transmitting and receiving radio waves, such as millimeter waves, are expected to be useful in a wide variety of fields. The present disclosure relates to providing electronic devices capable of detecting objects with high accuracy, such as radar devices equipped with an appropriate radome, and a design method for such electronic devices. According to one embodiment, it is possible to provide electronic devices capable of detecting objects with high accuracy, such as radar devices equipped with an appropriate radome, and a design method for such electronic devices.

[0010] In the present disclosure, an "electronic device" may refer to a device that is driven by electricity. A "user" may refer to a person (typically a human) or an animal that uses an electronic device according to an embodiment. A user may also refer to a person that uses a design method for an electronic device according to an embodiment. A user may include a person that monitors a target, such as a human, by using an electronic device according to an embodiment. A "target" may also refer to a person (e.g., a human or an animal) that is monitored by an electronic device according to an embodiment. A user may also include a target. A target is not limited to a human or an animal, but may also be a predetermined object. Here, a predetermined object may be, for example, a robot, a power tool, or an audio device.

[0011] An electronic device according to an embodiment can detect the heartbeat of a human or other target 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 of employees. Similarly, it is extremely important to understand and / or manage the health of patients and medical professionals in a hospital, and 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 of a target, without being limited to the aforementioned facilities such as companies, hospitals, and nursing homes. Such facilities may also include non-commercial facilities, 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 one embodiment may be used in a moving object 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.

[0012] An electronic device according to an embodiment may be used, for example, in a nursing facility or the like, to detect or monitor the heartbeat of a subject, such as a person requiring nursing care or care. Furthermore, when an abnormality is detected in the heartbeat of a subject, such as a person requiring nursing care or care, the electronic device according to an embodiment may issue a predetermined warning to the subject and / or other persons. Therefore, the electronic device according to an embodiment may allow the subject and / or staff at a nursing facility or the like to recognize that an abnormality is detected in the pulse of a subject, such as a person requiring nursing care or care. On the other hand, when no abnormality is detected in the heartbeat of a subject, such as a person requiring nursing care or care, (e.g., recognized as normal), the electronic device according to an embodiment may notify the subject and / or other persons to that effect. Therefore, the electronic device according to an embodiment may allow the subject and / or staff at a nursing facility or the like to recognize that the pulse of a subject, such as a person requiring nursing care or care, is normal.

[0013] 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.

[0014] 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.

[0015] Hereinafter, as a typical example, an electronic device according to an embodiment will be described as being stationary. Meanwhile, the subject (human) whose 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 normal radar sensor. Furthermore, 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.

[0016] An electronic device according to an embodiment will be described in detail below with reference to the drawings. First, a configuration of the electronic device according to an embodiment will be described.

[0017] 1 and 2 are diagrams illustrating the configuration of an electronic device according to an embodiment. FIG. 1 is a perspective view of the electronic device according to an embodiment. FIG. 2 can be a cross-sectional view or an end view of the electronic device according to an embodiment. In addition, both FIGS. 1 and 2 show the internal structure of the electronic device according to an embodiment in a transparent manner.

[0018] 1 and 2, an electronic device 1 according to an embodiment may include a transmitting antenna array 24, a receiving antenna array 31, a housing 70, a cover 80, and a substrate 90. The electronic device 1 shown in FIG. 1 is an example in which there is one channel for each of transmission and reception. However, the electronic device 1 according to an embodiment may have any number of channels for each of transmission and reception.

[0019] The transmitting antenna array 24 may be an array of antennas that transmit radio waves such as millimeter waves. The receiving antenna array 31 may be an array of antennas that receive radio waves transmitted by the transmitting antenna array 24, reflected by a predetermined object, for example. The transmitting antenna array 24 and the receiving antenna array 31 shown in FIG. 1 are each shown as an array of three patch antennas. However, the transmitting antenna array 24 and the receiving antenna array 31 may each be an array of any number of patch antennas as required. The transmitting antenna array 24 and the receiving antenna array 31 may be made of a metal body such as copper.

[0020] 1 and 2, the transmitting antenna array 24 may transmit a transmission wave including a component in the positive direction of the Z axis, and the receiving antenna array 31 may transmit a reflected wave including a component in the negative direction of the Z axis.

[0021] 1 and 2, the transmitting antenna array 24 and the receiving antenna array 31 may each be formed on a substrate 90. The substrate 90 may be made of a low-loss dielectric material such as glass epoxy. The transmitting antenna array 24 and the receiving antenna array 31 may be arranged on the front surface (the surface facing the positive direction of the Z axis) of the substrate 90. Furthermore, a circuit for generating a signal to be transmitted and / or a circuit for processing a signal to be received may be arranged on the back surface (the surface facing the negative direction of the Z axis) of the substrate 90.

[0022] The substrate 90 shown in FIGS. 1 and 2 is shown as being rectangular, such as a square. However, in one embodiment, the substrate 90 may have any shape as needed. Furthermore, the substrate 90 is not necessarily limited to a flat, plate-like member, but may also be, for example, a member with a curved surface. Furthermore, the thickness (in the Z-axis direction) of the substrate 90 is not particularly limited, but may be relatively thin, for example, about 1 mm to 2 mm. Furthermore, the size (in the X and Y directions) of the substrate 90 is not particularly limited, but may be relatively small, for example, about several centimeters.

[0023] 1 and 2, the housing 70 may have a structure that protects at least one of the transmitting antenna array 24, the receiving antenna array 31, and the substrate 90. For example, the housing 70 may be configured to include a bottom surface and four side surfaces surrounding the bottom surface. The housing 70 may have any size that can accommodate at least one of the transmitting antenna array 24, the receiving antenna array 31, and the substrate 90. Furthermore, the housing 70 may have any shape that can accommodate, for example, the substrate 90 inside. The housing 70 may be configured from a resin material such as ABS, acrylic, or PET (polyethylene terephthalate).

[0024] The cover unit 80 may cover the housing 70 that houses the transmitting antenna array 24, the receiving antenna array 31, and the substrate 90. The cover unit 80 may also be configured to cover at least a portion of at least one of the transmitting antenna array 24 and the receiving antenna array 31. Like the housing 70, the cover unit 80 may be made of a resin material such as ABS, acrylic, or PET. The cover unit 80 may have any size that is capable of covering at least a portion of at least one of the transmitting antenna array 24 and the receiving antenna array 31. The cover unit 80 may also have a size designed according to the opening of the housing 70.

[0025] The cover unit 80 shown in FIGS. 1 and 2 is shown as being rectangular, such as a square. However, in one embodiment, the cover unit 80 may have any shape as needed. Furthermore, the cover unit 80 is not necessarily limited to a flat, plate-like member, but may also be, for example, a member with a curved surface. Furthermore, the cover unit 80 may include, for example, at least a portion of the housing 70 shown in FIGS. 1 and 2. Hereinafter, the thickness (in the Z-axis direction) of the cover unit 80 will be referred to as Tk as shown in FIG. 2. The thickness Tk of the cover unit 80 may be, for example, approximately 1 mm to 2 mm. Furthermore, the size (in the X and Y directions) of the cover unit 80 is not particularly limited, but may be relatively small, for example, approximately several centimeters.

[0026] The cover 80 may be configured as a so-called radome. The radome protects the antenna from natural elements such as wind, rain, snow, sand, ice, and sunlight, while concealing the antenna and / or electronic device from the outside. Radomes are generally made of materials with high radio wave transmittance, such as glass fiber or Teflon (registered trademark). In the case of the electronic device 1 (a planar radar device) shown in FIGS. 1 and 2, the radome may be, for example, a planar cover member. Here, the radome may refer only to the cover 80 of the electronic device 1 shown in FIGS. 1 and 2. Alternatively, the radome may include not only the cover 80 of the electronic device 1 shown in FIGS. 1 and 2, but also at least a portion of the housing 70.

[0027] 2, the distance Gp between the cover part 80 and at least one of the transmitting antenna array 24 and the receiving antenna array 31 arranged on the substrate 90 may be, for example, 2.42 mm. Here, the distance Gp may be set to 2.42 mm based on the length of half the wavelength (λ / 2) of a 62 GHz radio wave.

[0028] Hereinafter, the electronic device 1 according to an embodiment will be described assuming that it is a radar device (radar sensor) based on millimeter-wave radar technology. However, the electronic device 1 according to an embodiment is not limited to a millimeter-wave radar device, and may be, for example, a radar device other than millimeter-wave radar. Furthermore, the electronic device 1 according to an embodiment is not limited to a radar device, and may be, for example, a device based on light-wave LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) technology. Furthermore, the electronic device 1 according to an embodiment may be, for example, a device based on technology that detects objects by transmitting and receiving sound waves or ultrasonic waves.

[0029] 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 that uses 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.

[0030] The radar system of the FMCW radar used in the present disclosure may include the FCM (Fast-Chirp Modulation) system, which transmits chirp signals at a shorter period than normal. The signals generated by the electronic device 1 are not limited to FMCW signals. The signals generated by the electronic device 1 may be signals of various systems other than the FMCW system. The transmission signal sequence stored in any memory unit may differ depending on these various systems. For example, in the case of the radar signal of the above-mentioned FMCW system, signals whose frequency increases and decreases for each time sample may be used. Since known technologies can be applied as appropriate to the various systems described above, further detailed explanations will be omitted.

[0031] 3 is a block diagram showing the functional configuration of the electronic device 1 according to an embodiment. An example of the functional configuration of the electronic device 1 according to an embodiment will be described below.

[0032] As shown in Fig. 3, the electronic device 1 according to one embodiment may include 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 time-series signal generation unit 13, and a frequency filter 14. As described above, Fig. 3 shows the functional configuration of the electronic device 1. For this reason, in Fig. 3, of the functional units shown in Figs. 1 and 2, the housing 70, the cover unit 80, and the board 90 are not shown.

[0033] Of the functional units shown in Fig. 3, the transmitting antenna array 24 and the receiving antenna array 31 may be installed on the front surface (the surface in the positive direction of the Z axis) of the substrate 90 shown in Fig. 1 and Fig. 2. Furthermore, of the functional units shown in Fig. 3, at least some of the functional units other than the transmitting antenna array 24 and the receiving antenna array 31 may be installed on the front surface (the surface in the positive direction of the Z axis) or the back surface (the surface in the negative direction of the Z axis) of the substrate 90 shown in Fig. 1 and Fig. 2. Furthermore, of the functional units shown in Fig. 3, at least some of the functional units other than the transmitting antenna array 24 and the receiving antenna array 31 may be installed inside or outside the housing 70 and the cover unit 80 shown in Fig. 1 and Fig. 2.

[0034] Moreover, the electronic device 1 according to an embodiment includes, as a transmitting unit, a transmitting DAC 21, a transmitting circuit 22, a millimeter-wave transmitting circuit 23, and a transmitting antenna array 24. Moreover, the electronic device 1 according to an embodiment includes, as a receiving unit, a receiving antenna array 31, a mixer 32, a receiving circuit 33, and a receiving ADC 34. The electronic device 1 according to an embodiment may not include at least one of the functional units shown in FIG. 3, or may include functional units other than the functional units shown in FIG. 3. The electronic device 1 shown in FIG. 3 may be configured to include a circuit configured basically in the same way as a general radar that uses electromagnetic waves in the millimeter-wave band or the like.

[0035] The signal processing unit 10 included in the electronic device 1 according to an embodiment can control the overall operation of the electronic device 1, including the control of each functional unit constituting the electronic device 1. In particular, the signal processing unit 10 performs various processes on signals handled by the electronic device 1. 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 be implemented based on various other known technologies. In an 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 also include a storage unit (memory) necessary for the operation of the signal processing unit 10, as appropriate.

[0036] The signal generation processing unit 11 of the signal processing unit 10 generates a signal to be transmitted from the electronic device 1. In the electronic device 1 according to one 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 periodically and linearly increases 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 pre-stored in a storage unit in the signal processing unit 10, for example. Chirp signals used in technical fields such as radar are well known, and therefore a detailed description thereof will be appropriately simplified or omitted. The signal generated by the signal generating processing unit 11 is supplied to the transmitting DAC 21. For this reason, the signal generating processing unit 11 (signal processing unit 10) may be connected to the transmitting DAC 21.

[0037] 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 signal converted into an analog signal 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.

[0038] 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.

[0039] The millimeter-wave transmission circuit 23 has the 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. 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.

[0040] The transmitting antenna array 24 is an array of multiple transmitting antennas. In Fig. 3, the configuration of the transmitting antenna array 24 is shown in a simplified form. The transmitting antenna array 24 transmits the signal processed by the millimeter-wave transmitting circuit 23 to the outside of the electronic device 1. The transmitting antenna array 24 may be configured to include a transmitting antenna array used in a general millimeter-wave radar.

[0041] In this way, the electronic device 1 according to one embodiment includes 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. As shown in Figures 1 and 2, the transmitting wave transmitted from the transmitting antenna array 24 may be transmitted to the outside of the electronic device 1 by passing through (transmitting) a cover unit 80 such as a radome.

[0042] 3, for example, it is assumed that an object 200 is present around the electronic device 1. In this case, at least a portion of the transmission waves transmitted from the transmitting antenna array 24 is reflected by the object 200. Of the transmission waves transmitted from the transmitting antenna array 24, at least a portion of those reflected by the object 200 may be reflected toward the receiving antenna array 31.

[0043] The receiving antenna array 31 receives the reflected waves. Here, the reflected waves may be at least a portion of the transmitted waves transmitted from the transmitting antenna array 24 that are reflected by the object 200.

[0044] The receiving antenna array 31 is an array of multiple receiving antennas. Fig. 3 shows a simplified configuration of the receiving antenna array 31. The receiving antenna array 31 receives reflected waves that are the result of reflection of the transmitted waves transmitted from the transmitting antenna array 24. As shown in Figs. 1 and 2, the receiving antenna array 31 may receive the reflected waves from outside the electronic device 1 by passing through (transmitting) a cover 80 such as a radome.

[0045] The receiving antenna array 31 may be configured to include a receiving antenna array used in a general millimeter-wave radar. The receiving antenna array 31 supplies the received signal received as a reflected wave to the mixer 32. For this reason, the receiving antenna array 31 may be connected to the mixer 32.

[0046] 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 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.

[0047] 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.

[0048] The receiving ADC (analog-to-digital converter) 34 has the 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 (receiving signal processing unit 12).

[0049] 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 DAC 34. For example, the reception signal processing unit 12 can calculate the distance from the electronic device 1 to the object 200 based on the digital signal supplied from the reception DAC 34 (distance measurement). The reception signal processing unit 12 can also calculate the relative speed of the object 200 with respect to the electronic device 1 based on the digital signal supplied from the reception DAC 34 (speed measurement). Furthermore, the reception signal processing unit 12 can calculate the azimuth angle of the object 200 as seen from the electronic device 1 based on the digital signal supplied from the reception DAC 34 (angle measurement).

[0050] 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 may perform a fast Fourier transform (2D-FFT) in the range direction and the velocity direction, respectively. Thereafter, the reception signal processing unit 12 may suppress false alarms and make the probability constant by removing noise points using processing such as CFAR (Constant False Alarm Rate). Then, the reception signal processing unit 12 obtains the position of the object 200 by estimating the angle of arrival for points that satisfy the CFAR criteria. Information generated as a result of measuring the range, speed, and angle by the reception signal processing unit 12 may be supplied to the time-series signal generating unit 13.

[0051] The time-series signal generating unit 13 generates a time-series signal indicating a motion such as vibration of the object 200 based on the information generated by the received signal processing unit 12. As described above, the received signal processing unit 12 can generate information on the results of measuring the distance, speed, and angle of the object 200. Therefore, based on at least a part of this information, for example, when the object 200 is moving in a manner such as slightly vibrating, the time-series signal generating unit 13 can generate a time-series signal indicating the vibration of the object 200. The time-series signal indicating the vibration of the object 200 generated by the time-series signal generating unit 13 may be supplied to the frequency filter 14.

[0052] The frequency filter 14 performs frequency filtering on the time-series signal supplied from the time-series signal generator 13. For example, the frequency filter 14 may perform a process to extract micro-Doppler components. The frequency filter 14 may also perform a process to extract motion, such as vibration, of the object 200. A radar device, such as a millimeter-wave radar, can measure the distance, angle, and velocity of multiple objects by using radio waves. Therefore, such a radar device can detect the velocity of the object using the Doppler shift of the received radio waves. Here, if the detected object moves and / or vibrates, the Doppler shift changes. This change in Doppler shift over time is called micro-Doppler. By analyzing the micro-Doppler, information about the motion, such as vibration, of the detected object can be obtained.

[0053] Information resulting from filtering by the frequency filter 14 may be supplied to, for example, a communication interface 50. For this reason, the frequency filter 14 (signal processing unit 10) may be connected to the communication interface 50. Information resulting from filtering output from the frequency filter 14 may be supplied to a functional unit other than the communication interface 50.

[0054] 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 the object 200 to the external device 60 as a signal such as a CAN (Controller Area Network). For example, at least one of information regarding the position, velocity, and angle of the object 200 may be supplied to the external device 60 via the communication interface 50. Furthermore, information regarding the motion, such as vibration, of the object 200 described above may also 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.

[0055] 3, the electronic device 1 according to an embodiment may be connected to an external device 60 via a communication interface 50 in a wired or wireless manner. In an embodiment, the external device 60 may be configured to include any computer and / or any control device. The electronic device 1 according to an embodiment may also be configured to include the external device 60. The external device 60 may have various configurations depending on how information about the movement, such as vibration, of the object 200 detected by the electronic device 1 is used. Therefore, a detailed description of the external device 60 will be omitted.

[0056] As described above, the electronic device 1 according to one embodiment transmits electromagnetic waves as transmission waves from the transmitting antenna array 24. For example, if a predetermined object (e.g., object 200 shown in FIG. 3) is present around the electronic device 1, at least a portion of the transmission waves transmitted from the electronic device 1 is reflected by the object and becomes a reflected wave. Then, by receiving such a reflected wave, for example, by the receiving antenna array 31 of the electronic device 1, the electronic device 1 can detect the object as a target.

[0057] Here, the object 200 may be, for example, a human being present around the electronic device 1. The object 200 may also be a living thing other than a human being, such as an animal present around the electronic device 1. Furthermore, the object 200 may be an object other than a living thing such as a human being or an animal. As described above, the object 200 may be moving, stationary, or static. In the present disclosure, the object detected by the electronic device 1 includes not only inanimate objects such as any object, but also living things such as people, dogs, cats, horses, and other animals. The object detected by the electronic device 1 of the present disclosure may also include targets including people, objects, and animals detected using radar technology.

[0058] In one embodiment, the cover 80 of the electronic device 1 can be designed by using information (for example, vibration waveform) about the movement, such as vibration, of the object 200 that is supplied to the external device 60.

[0059] The design of the cover 80 of the electronic device 1 according to one embodiment will be further described below.

[0060] As described above, the electronic device 1 according to an embodiment can be realized as a device based on radar technology, such as a millimeter-wave radar sensor including a transmitting antenna array 24 and a receiving antenna 31. The electronic device 1 according to an embodiment can perform Doppler analysis using the distance to a detected object and the velocity component of the object. When the electronic device 1 according to an embodiment includes a cover member 80 (and a housing 70) such as a radome, it is desirable to configure the electronic device 1 so as to suppress reflected power in order to avoid degradation of the Doppler characteristics as much as possible. Therefore, a design method for the electronic device 1 according to an embodiment relates to appropriately designing the cover member 80 (and a housing 70) such as a radome. The electronic device 1 according to an embodiment may include a cover member 80 (and a housing 70) such as a radome that is appropriately designed using the design method described above.

[0061] The electronic device 1 according to an embodiment can be realized as a high-frequency (e.g., 20 GHz or higher) Doppler radar in the millimeter wave band or higher that can measure distance (ranging), estimate angle (angle measurement), and detect Doppler velocity using electromagnetic waves or sound waves. Therefore, the electronic device 1 according to an embodiment may be realized as a radar device using a frequency band higher than millimeter waves, as a micro-Doppler, that detects vibrations localized at a certain position. In such a case, it is desirable that the radome-like cover 80 (and the housing 70) of the electronic device 1 according to an embodiment be optimally designed.

[0062] A wide range of vibrations can be detected by radar with high frequencies of millimeter waves or higher, such as vibrations from robots, power tools, and audio equipment, as well as rigid body motion, human or animal heartbeats, breathing, pulses, and movements. In general, for a radar device to detect micro-Doppler, it is necessary to accurately capture the phase between IF signals corresponding to each chirp signal obtained through modulation, transmission, reception, and mixing using FCM or FMCW, etc.

[0063] Therefore, in order for the electronic device 1 according to the embodiment to detect vibrations such as micro-Doppler, the following two points are important: First aspect: Increasing isolation between the transmitting antenna array 24 and the receiving antenna array 31 Second aspect: To reduce reflection of a transmission wave transmitted from the transmitting antenna array 24 and / or a reflected wave received by the receiving antenna array 31 by a cover part 80 (and the housing 70) such as a radome.

[0064] When the port of the transmitting antenna array 24 is defined as 1 and the port of the receiving antenna array 31 is defined as 2, and an S parameter (Scattering parameter) is defined, the above-mentioned first and second viewpoints can be written as follows: First perspective: S 21 To reduce Second perspective: S 11 and / or S 22 To reduce

[0065] In order to realize the above-mentioned first and second aspects, it is assumed that the following design matters should be taken into consideration. Design item 1: Design of antenna array and basic structure Design point 2: Design of clearance and thickness of cover part 80 Design point 3: Narrowing down design criteria through electromagnetic field analysis These designs are further described below.

[0066] In design item 1, the directivity of antennas such as the transmitting antenna array 24 and the receiving antenna array 31 may be controlled. Specifically, array design may be performed to improve the performance of antenna arrays such as the transmitting antenna array 24 and the receiving antenna array 31. Here, array design may refer to, for example, the design of the far field and near field by designing the number of arrays such as the transmitting antenna array 24 and the receiving antenna array 31, and the coefficients of amplitude and phase for each channel (antenna) of the array.

[0067] In design item 2, the following geometric design may be performed using a one-dimensional model based on the wavelength of the transmission wave transmitted from the transmitting antenna array 24. The clearance (gap Gp shown in FIG. 2) between the transmitting antenna array 24 and the receiving antenna array 31 and the cover part 80 is designed to be half the wavelength (λ / 2) of the transmitting wave in the air. The thickness of the cover part 80 (thickness Tk shown in FIG. 2) is designed to be half the wavelength (λ / 2√ε) of the transmission wave, taking into consideration the wavelength shortening rate of the material that constitutes the cover part 80, such as a radome.

[0068] In design item 3, optimization may be performed by calculation based on an actual geometric model, taking into consideration that the actual arrangement of the transmitting antenna array 24, the receiving antenna array 31, and the cover unit 80 has a three-dimensional expanse. When performing calculations based on the actual geometric model, the transmitting antenna array 24, the receiving antenna array 31, and the cover unit 80 may be optimized by performing calculations using electromagnetic field simulations, etc. Here, the electromagnetic field simulation may be performed using the finite element method (FEM), the finite difference time, domain method (FDTD), or the like.

[0069] However, when detecting vibrations of an object 200, as in the electronic device 1 according to an embodiment, it is expected that sufficient phase accuracy between chirp signals cannot be achieved with the above-described design alone. Therefore, in the electronic device 1 according to an embodiment, evaluation design is performed with a focus on the phase accuracy between chirp signals. That is, it is difficult to analytically or numerically calculate the final vibration detection capability of the radar using the design result information of the above-described design items 1 to 3, S parameters, far-field directivity, near-field electromagnetic field distribution, and the like. Therefore, in the electronic device 1 according to an embodiment, a vibration detection capability evaluation system is used to evaluate the design results and design the cover 80 (and the housing 70).

[0070] In this way, the electronic device 1 according to one embodiment may include the cover 80 (and the housing 70) designed using a method for evaluating the detection capability of a radar that uses a vibrating body. Also, in one embodiment, a method for designing the cover 80 (and the housing 70) of the electronic device 1 is provided by using a method for evaluating the detection capability of a radar that uses a vibrating body.

[0071] Here, in the electronic device 1 according to one embodiment, the cover 80 (and the housing 70) may be designed taking into consideration the above design items 1 to 3. For example, the above-mentioned Patent Document 3 (JP 2012-93305 A) can be considered to focus on the above-mentioned design item 3. Patent Document 3 proposes an attempt to improve the isolation between the transmitting and receiving antennas by providing a partition wall between the transmitting and receiving antennas.

[0072] Patent Document 3 discloses that radar waves in the millimeter wave band (76.5 GHz in this embodiment) are transmitted and received to obtain information (distance, relative speed, direction, etc.) about targets (preceding vehicles, obstacles on the road, roadside objects, etc.) that reflect the radar waves. The front wall of the radome disclosed in Patent Document 3 has a partition wall that divides the internal space into two rectangular parallelepiped spaces, and is integrally molded with the other parts of the radome. It is also disclosed that the thickness of the radome, including the partition wall, is formed to be about half the wavelength of the radar waves used (approximately 2 mm).

[0073] However, the above-described design raises the following concerns.

[0074] In other words, the partition wall between the transmitting and receiving antennas significantly changes the near-field and far-field directivity of the antenna from the characteristics of the originally designed antenna array. Therefore, even if the isolation between the receiving and receiving antennas is improved, the antenna performance itself may be deteriorated. Furthermore, it is expected that the radome (including the partition wall) designed as described above may not be able to fully achieve the desired characteristics in view of the first and second viewpoints described above.

[0075] Therefore, in order to solve the above-mentioned concerns, the electronic device 1 according to one embodiment has the cover unit 80 (and the housing 70) designed using a system that evaluates the performance of the radar in detecting vibrations. According to the design method for the electronic device 1 according to one embodiment, it is possible to design a radome and / or housing structure that maximizes the ability to detect vibrations. That is, the electronic device 1 according to one embodiment can be provided with a radome / housing structure that maximizes the ability to detect vibrations.

[0076] An example of optimizing the thickness of the cover section 80 when the distance Gp from the transmitting antenna array 24 and the receiving antenna array 31 to the cover section 80 is 2.42 mm, as shown in Fig. 2, is shown below. Here, the distance Gp may be set to 2.42 mm based on the length of half the wavelength (λ / 2) of a 62 GHz radio wave.

[0077] 4 is a flowchart illustrating a method for designing a cover 80 of an electronic device 1 according to one embodiment. In one embodiment, the cover 80 of the electronic device 1 can be designed by following the steps shown in the flowchart of FIG.

[0078] 4 starts, first, the above-mentioned design item 1, i.e., the design of the antenna array and basic structure, is performed (step S11). In step S11, as described above, the directivity of antennas such as the transmitting antenna array 24 and the receiving antenna array 31 may be controlled.

[0079] Next, the above-mentioned design item 2, i.e., the clearance and the thickness of the cover portion 80, is designed (step S12). In step S12, the clearance may be designed as the distance Gp (see FIG. 2) between the transmitting antenna array 24 and the receiving antenna array 31 and the cover portion 80. Also, in step S12, the thickness Tk shown in FIG. 2 may be designed as the thickness of the cover portion 80.

[0080] Steps S11 and S12 may be performed in the reverse order.

[0081] In one embodiment, N design rules may be determined (step S13) through the design steps S11 and S12. That is, at the time of step S13, design parameters for N electronic devices 1 with different configurations may be determined.

[0082] Once the N design criteria have been determined, electromagnetic field analysis may then be performed using the electronic device 1 designed for each of them (step S14). That is, in step S14, electromagnetic field analysis may be performed one after another for the N design criteria. In step S14, if it is determined that the predetermined basic performance is satisfied as a result of the electromagnetic field analysis performed for a certain design criteria n (≦N) (Yes in step S15), the process proceeds to the operation of step S17. On the other hand, if it is determined that the predetermined basic performance is not satisfied as a result of the electromagnetic field analysis performed for a certain design criteria n (≦N) (No in step S15), the electromagnetic field analysis of step S14 may be performed for the next design criteria n+1 (step S16). In this way, in steps S14 to S16, the above-mentioned design item 3, i.e., the design criteria may be narrowed down by electromagnetic field analysis.

[0083] In step S15, it may be determined whether the design criteria satisfy the basic performance based on the S parameters and / or realized gain. An example of narrowing down the design criteria by the electromagnetic field analysis executed in steps S14 to S16 will be further described below.

[0084] Fig. 5 is a diagram showing an example of the electromagnetic field analysis performed in step S14. Fig. 5 shows an example of the results of electromagnetic field calculation (finite element method) showing the degree to which the isolation between the transmitting antenna array 24 and the receiving antenna array 31 depends on the cover part 80. That is, Fig. 5 shows the results of S, which is the first viewpoint described above, when the thickness Tk of the cover part 80 is changed in several ways. 21 FIG. 10 is a diagram illustrating whether or not is reduced.

[0085] The horizontal axis of FIG. 5 indicates the frequency of the transmission wave, and the vertical axis of FIG. 5 indicates the S 21 That is, the vertical axis of Fig. 5 indicates the reflected power from port 1 to port 2, and the smaller this value, the better the characteristics. In Fig. 5, an example is shown in which the cover part 80 (radome) is made of ABS resin. Furthermore, the thickness Tk of the cover part 80 (radome) was varied from 1.0 mm to 1.6 mm, and set to 0.2 mm of PET film, and the best six were selected from these, and their calculated values ​​are shown.

[0086] Furthermore, considering that the relative dielectric constant of ABS resin is 3.4, the wavelength when the transmission wave is 62 GHz is 1.31 mm. Therefore, the design criteria are set to ±0.3 mm around this. Furthermore, because a very thin PET film is likely to transmit radio waves, this is set as the design criteria in Figure 5. For reference, Figure 5 also shows an example without a radome. In the example shown in Figure 5, the best results are obtained when the thickness Tk of the cover portion 80 (radome) is 1.4 mm, compared to when there is no cover portion 80 (radome). However, this result alone does not necessarily mean that the design result is optimal.

[0087] Fig. 6 is a diagram showing the degree of realized gain of the electronic device 1 when the thickness Tk of the cover part 80 is changed in several ways. The horizontal axis in Fig. 6 indicates the frequency of the transmitted wave, and the vertical axis in Fig. 5 indicates the realized gain. That is, the higher the value on the vertical axis in Fig. 6, the higher the gain.

[0088] As shown in Figure 6, when the thickness Tk of the cover portion 80 (radome) is 0.2 mm PET film, the gain is higher than when there is no cover portion 80 (radome). Also, as shown in Figure 6, the next highest gain after when the thickness Tk of the cover portion 80 (radome) is 0.2 mm PET film is when the thickness Tk of the cover portion 80 (radome) is 1.4 mm. On the other hand, when the thickness Tk of the cover portion 80 (radome) is 1.5 mm, it can be seen that the frequency characteristics become different from the others. In this case, the gain is lowest, especially in the 63 GHz band.

[0089] 5 and 6, the design criteria that provide the lowest isolation between transmitter and receiver and the design criteria that provide the best operating gain are not necessarily the same. Therefore, the optimal conditions for the thickness Tk of the cover portion 80 (radome) cannot be derived solely by narrowing down the design criteria through the electromagnetic field analysis in steps S14 to S16. For this reason, in one embodiment, the narrowing down of the design criteria through the electromagnetic field analysis in steps S14 to S16 may be merely used as a reference condition for narrowing down the design criteria.

[0090] Therefore, in one embodiment, a prototype of the electronic device 1 that satisfies the M (1≦M≦N) design criteria narrowed down as a result of step S15 shown in Fig. 4 may be created, and steps S17 and S18 may be performed on the electronic device 1. In step S17, the prototype of the electronic device 1 that satisfies the design criteria and has passed steps S14 and S15 is used to evaluate the ability to detect vibration of the object 200. After the evaluation of the ability to detect vibration is performed in step S17, the optimal design criteria for the electronic device 1 can be selected based on the results of the evaluation (step S18).

[0091] The evaluation of the ability to detect vibrations of the object 200, which is performed in step S17, may involve, for example, comparing the magnitude-squared coherence (MSC) using the vibrating body and a reference machine (measuring instrument). As a result of this comparison, it is possible to select the electronic device 1 with the optimal conditions. The comparison of the magnitude-squared coherence (MSC) using the vibrating body and a reference machine (measuring instrument) will be further described below.

[0092] FIG. 7 is a diagram illustrating a schematic configuration of an evaluation system (hereinafter simply referred to as "evaluation system") that evaluates the vibration detection capability shown in step S17 of FIG.

[0093] As shown in FIG. 7, the evaluation system may include a vibration source 210, a reference machine 310, a signal generator 320, an amplifier 330, and a data logger 340 in addition to the electronic device 1 to be evaluated.

[0094] The electronic device 1 shown in FIG. 7 may be a prototype electronic device 1 that satisfies M (1≦M≦N) design criteria narrowed down as a result of step S15 shown in FIG. 4, for example. Furthermore, the vibration source 210 may be configured to include a vibrating object, such as the object 200 shown in FIG. 3. In one embodiment, the vibration source 210 may include, for example, a loudspeaker that converts electrical vibrations into physical vibrations. In one embodiment, the reference machine 310 may be, for example, a laser vibrometer. The signal generator 320 generates a test signal to be output from the vibration source 210. The amplifier 330 may include, for example, an audio amplifier that amplifies the test signal to be output from the vibration source 210. The data logger 340 logs data output from the electronic device 1 and the reference machine 310.

[0095] The signal generated by signal generator 320 shown in Fig. 7 may be, for example, a chirp signal of 500 Hz or less. Furthermore, the dynamic range of the signal generated by signal generator 320 may be, for example, from -30 dB to 0 dB, with the level gradually decreasing by 3 dB over time. By using such a signal, the vibration amplitude of vibration source 210 (loudspeaker) can be changed from a large state to a small state, and it can be confirmed at what level the electronic device 1 reaches its limit for signal detection. Furthermore, as shown in Fig. 7, the distance between vibration source 210 and electronic device 1 is set to 50 cm.

[0096] 8 and 9 are diagrams showing examples of signals input from signal generator 320 to vibration source 210 in the evaluation system shown in FIG. 7. FIG. 8 shows the overall time-series waveform of the signal. The horizontal axis of FIG. 8 indicates time, and the vertical axis of FIG. 8 indicates signal level. FIG. 9 shows a spectrogram at level 1. The horizontal axis of FIG. 9 indicates time, and the vertical axis of FIG. 9 indicates frequency. The results shown in FIGS. 8 and 9 make it possible to confirm the above-mentioned signal specifications.

[0097] Based on the evaluation system shown in Fig. 7 and the signals shown in Fig. 8 and Fig. 9, the quality of data on vibrations of the object 200 or the like detected by the electronic device 1 can be inspected against the reference device 310. The statistics used for the inspection will be described below.

[0098] In the evaluation system shown in FIG. 7, the squared amplitude coherence C xy can be expressed as the following equation (1). Here, the frequency of the signal (audio signal) shown in Figs. 8 and 9 is assumed to be f [Hz]. Also, the time-series signal vector of the vibration detected by the reference device 310 is assumed to be x, and the time-series signal vector of the vibration detected by the electronic device 1 is assumed to be y. Furthermore, the power spectrum density of each of x and y is assumed to be P xx (f) and P yy (f).

number

[0099] The squared amplitude coherence C shown in the above equation (1) xy By averaging within a predetermined frequency band, the final statistical quantity shown in the following equation (2) can be obtained.

number

[0100] For the design criteria narrowed down by the electromagnetic field analysis shown in step S14 of FIG. 4, the statistics calculated by the above formula (2) may be integrated with f0=20 [Hz] and f1=400 [Hz].

[0101] Figure 10 shows the above results for several design criteria of the prototype electronic device 1. The horizontal axis of Figure 10 represents the level of the chirp signal, and the vertical axis of Figure 10 represents the averaged magnitude-squared coherence.

[0102] As can be seen from FIG. 10, the electronic device 1 configured as described above has the highest mean squared amplitude coherence when there is no cover unit 80 (radome). Furthermore, when the signal level is between -12 and -30 dB, the electronic device 1 has the highest mean squared amplitude coherence when the cover unit 80 (radome) thickness Tk is 1.4 mm. Furthermore, when the signal level is between 0 and -12 dB, the electronic device 1 has a relatively higher mean squared amplitude coherence when the cover unit 80 (radome) thickness Tk is 1.4 mm than when it is other than 1.5 mm. On the other hand, the squared amplitude coherence is low at all signal levels when the cover unit 80 (radome) thickness Tk is 1.5 mm. Therefore, the electronic device 1 configured as described above can maximize its vibration detection capability by setting the cover unit 80 (radome) thickness Tk to 1.4 mm.

[0103] Therefore, according to the design method of the electronic device 1 of the embodiment, it is possible to optimize the thickness Tk of the cover part 80 (radome) of the electronic device 1. Furthermore, the electronic device 1 according to the embodiment designed in this manner can detect an object (particularly, the movement of an object, such as vibration) with good accuracy by optimizing the thickness Tk of the cover part 80 (radome) of the electronic device 1.

[0104] (Other embodiments) Other embodiments will be described below.

[0105] In other embodiments, at least some of the steps may be omitted as appropriate rather than performing all of the steps shown in Fig. 4. For example, in other embodiments, steps S14 to S16 shown in Fig. 4 may be skipped, thereby omitting the electromagnetic field analysis.

[0106] In other embodiments, the vibration source 210 shown in FIG. 5 is not limited to a loudspeaker, but may be any transducer capable of generating planar vibrations, such as a piezoelectric vibrator or an electrostatic speaker / actuator.

[0107] In another embodiment, the input signal to the vibration source 210 as shown in FIGS. 8 and 9 is not limited to a chirp signal, but may be, for example, a frequency step signal that changes discretely for each frequency step.

[0108] Furthermore, other embodiments are not limited to designing only the thickness Tk of the cover unit 80 (radome) of the electronic device 1 according to one embodiment. For example, other embodiments may be designed to design any hardware of the device that detects vibrations, such as the entire housing 70, the transmitting antenna array 24, and / or the receiving antenna array 32.

[0109] Furthermore, the chirp signal input to the vibration source 210 as shown in FIGS. 8 and 9 may be, for example, a step tone signal or a TSP (time stretched pulse) signal.

[0110] Furthermore, the band and / or dynamic range of the signal input to the vibration source 210 as shown in FIGS. 8 and 9 may be set arbitrarily.

[0111] In the above formula (2), the average within the frequency band is calculated. However, in other embodiments, other statistics such as the statistical median, maximum value, or minimum value may be used. Furthermore, when averaging as in the above formula (2), in order to weight important frequency bands, a weighting coefficient w(f) may be multiplied, and calculation may be performed, for example, as in the following formula (3):

number

[0112] (About the subject of design criteria) In the above-described embodiment, the accuracy of detecting an object by an electronic device such as a radar device is improved by considering (optimizing) the design of the cover unit 80 (and the housing 70) such as a radome. In particular, the above-described embodiment has been described with reference to the case where the design of the clearance (gap Gp) between the transmitting antenna array 24 and the receiving antenna array 31 and the cover unit 80, and / or the design of the thickness (thickness Tk) of the cover unit 80 is optimized. However, the above-described embodiment is not limited to optimizing the design of the gap Gp and / or the design of the thickness Tk. Furthermore, the above-described embodiment is not limited to optimizing the design of the cover unit 80 and / or the housing 70. That is, in the above-described embodiment, the target for considering the design criteria is not limited to the size of the gap Gp and / or the thickness Tk, nor is it limited to the cover unit 80 and / or the housing 70.

[0113] As described above, in order for a radar device to detect micro-Doppler, it is necessary to accurately capture the phase between IF signals corresponding to each chirp signal, which is obtained through modulation, transmission, reception, and mixing using FCM or FMCW, etc. However, in a radar device, noise may occur or signals may be degraded due to various hardware and / or software used. This makes it difficult to accurately capture the phase between IF signals corresponding to each chirp signal as described above. In this case, the accuracy of the phase between chirps deteriorates, making it difficult to accurately detect the micro-Doppler signal. Therefore, in the above-described embodiment, the first aspect (S 21 (reducing) and the second perspective (S 11 and / or S 22 Based on this, the spacing Gp and / or thickness Tk were considered as design criteria.

[0114] On the other hand, even when changing the design criteria to include targets other than the distance Gp and / or the thickness Tk, noise may occur or the signal may be degraded due to the various hardware and / or software used. Therefore, by considering targets other than the distance Gp and / or the thickness Tk as targets for the design criteria, the accuracy with which the radar device detects objects can be improved. Below, a case will be described in which targets other than the distance Gp and / or the thickness Tk are considered as targets for the design criteria.

[0115] FIG. 11 is a flowchart illustrating a method for designing an electronic device 1 according to one embodiment. FIG. 11 is a diagram illustrating a design method in which targets other than the cover portion 80 of the electronic device 1 are included in the design criteria in the method described in FIG. 4. In FIG. 11, descriptions that are the same as or similar to those already described in FIG. 4 are simplified or omitted as appropriate. In one embodiment, the electronic device 1 can be designed by following the steps shown in the flowchart in FIG. 11.

[0116] When the design method shown in FIG. 11 starts, a predetermined target is first designed as a target of the design criteria for the electronic device 1 (step S21). The predetermined target to be designed in step S21 may be various targets based on various viewpoints of the electronic device 1. For example, the predetermined target may be the shape, size, material, or structure of the cover 80 and / or the housing 70. The predetermined target may also be the number of channels of the transmitting antenna array 24 and / or the receiving antenna array 31. The predetermined target may also be the number, shape, size, material, or arrangement of the antenna elements constituting the transmitting antenna array 24 and / or the receiving antenna array 31. The predetermined target may also be the distance between the antenna elements constituting the transmitting antenna array 24 and / or the receiving antenna array 31, the connection state between the antenna elements, the number of feed points that feed power to the antenna elements, or the distance to the feed points that feed power to the antenna elements. Alternatively, the predetermined target may be various targets related to the hardware and / or software constituting the electronic device 1. The predetermined target may also be various targets that may affect noise in the electronic device 1.

[0117] In step S21, the antenna array and basic structure may be designed as in step S11 shown in Fig. 4. Also, in step S21, the clearance (the distance Gp between the transmitting antenna array 24 and the receiving antenna array 31 and the cover section 80) and the thickness (thickness Tk) of the cover section 80 may be designed as in step S12 shown in Fig. 4. That is, in step S21, a design may be performed based on a viewpoint that includes at least a part of the above-mentioned design item 1 and / or design item 2.

[0118] In one embodiment, for example, N design rules may be determined through the design in step S21 (step S22). That is, at the time of step S22, design parameters for N electronic devices 1 having different configurations may be determined.

[0119] Once the N design rules have been determined, a predetermined design simulation may then be performed using each of the designed electronic devices 1 (step S23). That is, in step S23, the predetermined design simulation may be performed one after another for the N design rules.

[0120] The predetermined design simulation performed in step S23 may be a simulation for determining whether the predetermined target designed in step S21 satisfies a basic predetermined performance. For example, assume that the size of the cover unit 80 is designed as the predetermined target in step S21. In this case, N different sizes of the cover unit 80 of the electronic device 1 may be determined in step S22. Then, in step S23, design simulations for the sizes of the cover unit 80 of the electronic device 1 may be performed sequentially for the N different sizes of the cover unit 80. The design simulation performed here may be a simulation of the design of the size of the cover unit 80, thereby determining whether any of the N different sizes of the cover unit 80 satisfies a basic predetermined performance. The electromagnetic field analysis performed in step S14 shown in FIG. 4 may be a specific example of the predetermined design simulation performed in step S23.

[0121] In step S23, if it is determined that the predetermined basic performance is satisfied as a result of performing a design simulation for a certain design criterion n (≦N) (Yes in step S24), the process proceeds to the operation of step S26. On the other hand, if it is determined that the predetermined basic performance is not satisfied as a result of performing an electromagnetic field analysis for a certain design criterion n (≦N) (No in step S24), the design simulation of step S23 may be performed for the next design criterion n+1 (step S25). In this way, in steps S23 to S25, the design criteria may be narrowed down by the design simulation.

[0122] In step S24, as described in step S15 of FIG. 4, it may be determined whether the design criteria satisfy the basic performance based on, for example, the S parameters and / or the realized gain.

[0123] Next, a prototype of the electronic device 1 that satisfies the M (1≦M≦N) design criteria narrowed down as a result of step S24 may be created, and steps S26 and S27 may be performed on the electronic device 1. In step S26, the prototype of the electronic device 1 that satisfies the design criteria and cleared steps S23 and S24 is used to evaluate the ability to detect vibration of the object 200. After the evaluation of the ability to detect vibration is performed in step S26, the optimal design criteria for the electronic device 1 can be selected based on the results of the evaluation (step S27).

[0124] The evaluation of the ability to detect vibrations of the object 200 performed in step S26 may involve, for example, comparing the magnitude-squared coherence (MSC) using the vibrating body and a reference device (measuring instrument) in the same manner as in step S17 of Fig. 4. As a result of this comparison, the electronic device 1 with the optimal conditions can be selected.

[0125] In step S26, similarly to step S17 described with reference to FIG. 4, an evaluation system such as that shown in FIG. 7 may be used to evaluate the ability to detect vibrations of the object 200.

[0126] The electronic device 1 shown in FIG. 7 may be, for example, an electronic device 1 prototyped to satisfy M (1≦M≦N) design criteria narrowed down as a result of step S24 shown in FIG. 11. Furthermore, the vibration source 210 may be configured to include a vibrating object, such as the object 200 shown in FIG. 3. In one embodiment, the vibration source 210 may include, for example, a loudspeaker that converts electrical vibrations into physical vibrations. In one embodiment, the reference machine 310 may be, for example, a laser vibrometer.

[0127] Meanwhile, in one embodiment, the reference machine 310 may be something other than a laser vibrometer. In one embodiment, the reference machine 310 may be, for example, a single microphone that collects sound or voice, or a microphone array that detects sound or voice in a predetermined direction. Also, in one embodiment, the reference machine 310 may be a piezoelectric vibration sensor (e.g., a piezo sensor) that detects vibrations by contacting a detection target. In this case, the reference machine 310 shown in FIG. 7 may be disposed so as to be in contact with the vibration source 210, rather than being disposed at a distance from the vibration source 210. Also, in one embodiment, the reference machine 310 may be configured based on the PPSI (Parallel Phase-Shifting Interferometry) method using a high-speed camera and an optical measurement method of a sound field.

[0128] As described above, in one embodiment, the accuracy with which the radar device detects an object may be improved by considering targets other than the above-mentioned gap Gp and / or thickness Tk as targets for the design criteria.

[0129] In this way, the design method for the electronic device 1 according to one embodiment may include a step of designing the predetermined specifications of the electronic device 1 based on the squared amplitude coherence.

[0130] In the embodiment shown in Fig. 11, at least some of the steps may be omitted as appropriate rather than performing all of the steps shown in Fig. 11. For example, in the embodiment shown in Fig. 11, steps S23 to S25 may be skipped, thereby omitting the design simulation.

[0131] While the present disclosure has been described based on various drawings and examples, it should be noted that those skilled in the art would easily be able to 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 contained in each functional unit can be rearranged so as not to cause logical inconsistencies. Multiple functional units may 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 may be implemented by combining features or omitting some features as appropriate. In other words, those skilled in the art can make various modifications and alterations 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, means, step, etc. can be added to other embodiments so as not to cause logical inconsistencies, or can be replaced with each functional unit, means, step, etc. of other embodiments. Furthermore, in each embodiment, multiple functional units, means, steps, 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.

[0132] The above-described embodiment is not limited to being implemented only as the electronic device 1. For example, the above-described embodiment may be implemented as a method for designing a device such as the electronic device 1.

[0133] The electronic device 1 according to the above-described embodiment has been described as including components constituting a so-called radar sensor, such as the transmitting antenna array 24 and the receiving antenna array 31. However, the electronic device according to an embodiment may be implemented as, for example, a configuration such as the signal processing unit 10. In this case, the signal processing unit 10 may be implemented as having a function of processing signals handled by, for example, the transmitting antenna array 24 and the receiving antenna array 31. [Explanation of symbols]

[0134] 1 Electronic equipment 10 Signal Processing Section 11 Signal generation processing section 12 Received signal processing section 13 Time series signal generator 14 Calculation section 21 Transmit DAC 22 Transmitting circuit 23 Millimeter wave transmitter circuit 24 Transmitting Antenna Array 31 Receiving Antenna Array 32 Mixer 33 Receiving circuit 34 Receive ADC 50 Communication Interface 60 External equipment 70 Case 80 Cover 90 PCB 200 objects 210 Vibration Source (Loudspeaker) 310 Reference Machine (Laser Vibrometer) 320 Signal Generator 330 Amplifier (Audio Amplifier) 340 Data Logger

Claims

1. a transmitting antenna for transmitting a transmission wave; a receiving antenna for receiving a reflected wave of the transmitted wave; a cover portion that covers at least a portion of at least one of the transmitting antenna and the receiving antenna; a signal processing unit that detects an object that reflects the transmission wave based on at least one of a transmission signal that is transmitted as the transmission wave and a reception signal that is received as the reflected wave; An electronic device comprising: At least a part of at least one of the transmission wave transmitted by the transmitting antenna and the reflected wave received by the receiving antenna is transmitted and / or received via the cover portion, the shape, size, material, or structure of at least one of the cover and the housing of the electronic device; the number of channels of at least one of the transmitting antenna and the receiving antenna; The number, shape, size, material, or arrangement of antenna elements constituting at least one of the transmitting antenna and the receiving antenna; and The distance between antenna elements constituting at least one of the transmitting antenna and the receiving antenna, the connection state between the antenna elements, the number of feeding points that feed power to the antenna elements, or the distance to the feeding points that feed power to the antenna elements, at least one of which is designed based on squared amplitude coherence.

2. The electronic device according to claim 1 , wherein the signal processing unit detects vibrations of an object that reflects the transmission wave based on at least one of a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave.

3. The electronic device according to claim 2 , wherein the signal processing unit detects the heartbeat of a human or animal that reflects the transmission wave based on at least one of a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave.

4. The electronic device according to claim 1 , wherein the thickness of the cover portion is designed based on squared amplitude coherence calculated by operating a predetermined vibration source and a predetermined reference machine.

5. 5. The electronic device according to claim 4, wherein the squared amplitude coherence is calculated based on a power spectral density of a time series signal vector of the vibration of the vibration source detected by the reference device and a time series signal vector of the vibration of the vibration source detected by the electronic device.

6. a transmitting antenna for transmitting a transmission wave; a receiving antenna for receiving a reflected wave of the transmitted wave; a cover portion that covers at least a portion of at least one of the transmitting antenna and the receiving antenna; a signal processing unit that detects an object that reflects the transmission wave based on at least one of a transmission signal that is transmitted as the transmission wave and a reception signal that is received as the reflected wave; A method for designing an electronic device comprising: At least a part of at least one of a transmission wave transmitted by the transmitting antenna and a reflected wave received by the receiving antenna is transmitted and / or received via the cover, the shape, size, material, or structure of at least one of the cover and the housing of the electronic device; the number of channels of at least one of the transmitting antenna and the receiving antenna; The number, shape, size, material, or arrangement of antenna elements constituting at least one of the transmitting antenna and the receiving antenna; and The distance between antenna elements constituting at least one of the transmitting antenna and the receiving antenna, the connection state between the antenna elements, the number of feeding points that feed power to the antenna elements, or the distance to the feeding points that feed power to the antenna elements, 4. A method for designing an electronic device, comprising the step of designing at least one of the above based on squared amplitude coherence.

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