Electronic device, method of controlling the same, and program

Abstract

To provide an electronic device capable of nicely detecting objects, a method of controlling the same, and a program.SOLUTION: An electronic device is provided, comprising a transmission antenna for transmitting a transmission wave, a reception antenna for receiving reflected waves of the transmission wave, a control unit for controlling a radiation pattern of the transmission wave, and a signal processing unit configured to detect objects based on a transmission signal transmitted as the transmission wave and reception signals received as the reflected waves. The control unit provides control such that at least one transmission wave with a modified radiation pattern is included when transmitting the transmission wave multiple times in a predetermined unit. The signal processing unit outputs an object detection result based on a cluster selected from among multiple clusters obtained by clustering each of multiple object detection results, where a distance between a representative point of a point cloud included in each cluster and a farthest point in the point cloud is the smallest in the selected cluster.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to an electronic device, a control method for an electronic device, and a program. [Background technology]

[0002] For example, in the field of the automobile industry, a technology for measuring the distance between a vehicle and a predetermined object is considered important. In particular, in recent years, various RADAR (Radio Detecting and Ranging) technologies have been researched, which transmit radio waves such as millimeter waves and receive the reflected waves from an object such as an obstacle to measure the distance between the vehicle and the object. The importance of such technology for measuring distance is expected to increase in the future with the development of technologies for assisting the driver in driving and technologies related to autonomous driving that automates part or all of driving.

[0003] In the above-mentioned radar-like technology, various clustering methods are known as algorithms for determining whether an object has been detected based on a received signal. For example, Patent Document 1 discloses an attempt to improve the quality of clustering and improve detection accuracy by adaptively adjusting clustering based on the characteristics of the detection target. In addition, DBSCAN (Density-based spatial clustering of applications with noise) is widely used as an algorithm for clustering data in accordance with density. When determining whether an object has been detected, it is expected that the object cannot be detected well if clustering is not performed appropriately. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-34025 Summary of the Invention [Problem to be solved by the invention]

[0005] There is a demand for a technology that can effectively detect a specific object by receiving a reflected wave of a transmitted wave that is reflected by the object.

[0006] An object of the present disclosure is to provide an electronic device, a control method for an electronic device, and a program that can detect an object well. [Means for solving the problem]

[0007] The 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 transmission wave; A control unit that controls a radiation pattern of the transmission wave; a signal processing unit that detects an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; Equipped with. The control unit controls the transmission wave so that, when the transmission wave is transmitted a plurality of times in a predetermined unit, the transmission wave includes at least one transmission wave with a changed radiation pattern. The signal processing unit outputs a detection result of the object based on a selected cluster from among multiple clusters obtained by clustering each of the results of detecting the object multiple times, the selected cluster having the shortest distance from a representative point of a point cloud contained in each cluster to the farthest point in the point cloud.

[0008] The 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 transmission wave; A control unit that controls a radiation pattern of the transmission wave; a signal processing unit that detects an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; Equipped with. The control unit controls the transmission wave so that, when the transmission wave is transmitted a plurality of times in a predetermined unit, the transmission wave includes at least one transmission wave with a changed radiation pattern. The signal processing unit outputs a detection result of the object based on a selected cluster obtained by performing clustering on each of the results of detecting the object multiple times, excluding the cluster having the largest area in which the point cloud is distributed from among multiple clusters obtained by performing clustering on each of the results of detecting the object multiple times.

[0009] A method for controlling an electronic device according to an embodiment includes: transmitting a transmission wave by a transmitting antenna; receiving a reflected wave of the transmission wave by a receiving antenna; controlling a radiation pattern of the transmission wave; detecting an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; a step of controlling the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, at least one transmission wave having a changed radiation pattern is included; a step of outputting a detection result of the object based on a selected cluster among a plurality of clusters obtained by performing clustering on each of the results of detecting the object a plurality of times, the selected cluster being the one in which the distance from a representative point of the point cloud included in each cluster to the most distant point in the point cloud is the shortest; Includes.

[0010] A method for controlling an electronic device according to an embodiment includes: transmitting a transmission wave by a transmitting antenna; receiving a reflected wave of the transmission wave by a receiving antenna; controlling a radiation pattern of the transmission wave; detecting an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; a step of controlling the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, at least one transmission wave having a changed radiation pattern is included; a step of outputting a detection result of the object based on a selected cluster obtained by performing clustering on each of the results of detecting the object multiple times, excluding a cluster having a largest distribution area of ​​a point cloud from among a plurality of clusters obtained by performing clustering on each of the results of detecting the object multiple times; Includes.

[0011] A program according to an embodiment includes: For electronic devices, transmitting a transmission wave by a transmitting antenna; receiving a reflected wave of the transmission wave by a receiving antenna; controlling a radiation pattern of the transmission wave; detecting an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; a step of controlling the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, at least one transmission wave having a changed radiation pattern is included; a step of outputting a detection result of the object based on a selected cluster among a plurality of clusters obtained by performing clustering on each of the results of detecting the object a plurality of times, the selected cluster being the one in which the distance from a representative point of the point cloud included in each cluster to the most distant point in the point cloud is the shortest; Execute the command.

[0012] A program according to an embodiment includes: For electronic devices, transmitting a transmission wave by a transmitting antenna; receiving a reflected wave of the transmission wave by a receiving antenna; controlling a radiation pattern of the transmission wave; detecting an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; a step of controlling the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, at least one transmission wave having a changed radiation pattern is included; a step of outputting a detection result of the object based on a selected cluster obtained by performing clustering on each of the results of detecting the object multiple times, excluding a cluster having a largest distribution area of ​​a point cloud from among a plurality of clusters obtained by performing clustering on each of the results of detecting the object multiple times; Execute the command. Effect of the Invention

[0013] According to one embodiment, it is possible to provide an electronic device, a control method for an electronic device, and a program that can detect an object well. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram illustrating a usage mode of an electronic device according to an embodiment. [Diagram 2] 1 is a functional block diagram illustrating a schematic configuration of an electronic device according to an embodiment. [Diagram 3] 1 is a diagram illustrating a configuration of a signal processed by an electronic device according to an embodiment. [Figure 4] FIG. 2 is a diagram illustrating signal processing by an electronic device according to an embodiment. [Diagram 5] FIG. 2 is a diagram illustrating signal processing by an electronic device according to an embodiment. [Figure 6] FIG. 2 is a diagram illustrating signal processing by an electronic device according to an embodiment. [Figure 7] 10 is a flowchart illustrating an operation of an electronic device according to an embodiment. [Figure 8] 10 is a flowchart illustrating an operation of an electronic device according to an embodiment. [Figure 9] FIG. 11 is a diagram illustrating an example of an operation of an electronic device according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, one embodiment will be described in detail with reference to the drawings.

[0016] The electronic device according to an embodiment is mounted on a vehicle (mobile body) such as an automobile, and is capable of detecting a predetermined object present around the mobile body as a target. To this end, the electronic device according to an embodiment can transmit a transmission wave to the surroundings of the mobile body from a transmission antenna installed on the mobile body. The electronic device according to an embodiment can also receive a reflected wave of the transmission wave from a receiving antenna installed on the mobile body. At least one of the transmission antenna and the receiving antenna may be provided on, for example, a radar sensor installed on the mobile body.

[0017] Hereinafter, as a typical example, a configuration in which an electronic device according to an embodiment is mounted on an automobile such as a passenger car will be described. However, the electronic device according to an embodiment is not limited to being mounted on an automobile. The electronic device according to an embodiment may be mounted on various moving bodies such as an autonomous driving automobile, a bus, a taxi, a truck, a taxi, a motorcycle, a bicycle, a ship, an aircraft, a helicopter, an agricultural machine such as a tractor, a snowplow, a cleaning vehicle, a police car, an ambulance, and a drone. The electronic device according to an embodiment is not necessarily limited to being mounted on a moving body that moves by its own power. For example, the moving body on which the electronic device according to an embodiment is mounted may be a trailer part towed by a tractor. The electronic device according to an embodiment does not necessarily have to be mounted on a moving body. For example, the electronic device according to an embodiment may be attached to or built into another device fixed to the ground. The electronic device according to an embodiment may be fixed to the ground, for example.

[0018] The electronic device according to an embodiment can measure the distance between a sensor and an object in a situation where at least one of the sensor and a predetermined object can move. The electronic device according to an embodiment can measure the distance between the sensor and an object even if both the sensor and the object are stationary. The automobiles included in the present disclosure are not limited by overall length, overall width, overall height, engine displacement, passenger capacity, or load capacity. For example, the automobiles of the present disclosure include automobiles with an engine displacement of more than 660cc and automobiles with an engine displacement of 660cc or less, so-called light automobiles. The automobiles included in the present disclosure also include automobiles that use electricity as part or all of their energy and use a motor.

[0019] (Configuration of an Electronic Device According to an Embodiment) First, an example of object detection by an electronic device according to an embodiment will be described.

[0020] Fig. 1 is a diagram illustrating a usage state of an electronic device according to an embodiment. Fig. 1 shows an example in which an electronic device including a transmitting antenna and a receiving antenna according to an embodiment is installed in a mobile object.

[0021] An electronic device 1 including a transmitting antenna and a receiving antenna according to an embodiment is installed in a moving body 100 shown in FIG. 1. The moving body 100 shown in FIG. 1 may be equipped with (for example, built-in) the electronic device 1 according to an embodiment. A specific configuration of the electronic device 1 will be described later. The electronic device 1 may include at least one of a transmitting antenna and a receiving antenna, for example, as described later. The moving body 100 shown in FIG. 1 may be an automobile vehicle such as a passenger car, but may be any type of moving body. In FIG. 1, the moving body 100 may be moving (running or slowly moving) in, for example, the positive direction of the Y axis (traveling direction) shown in the figure, or may be moving in another direction, or may be stationary without moving.

[0022] As shown in FIG. 1, an electronic device 1 equipped with a transmitting antenna is installed in a moving body 100. In the example shown in FIG. 1, only one electronic device 1 equipped with a transmitting antenna and a receiving antenna is installed in the front of the moving body 100. Here, the position where the electronic device 1 is installed in the moving body 100 is not limited to the position shown in FIG. 1, and may be other positions as appropriate. For example, the electronic device 1 as shown in FIG. 1 may be installed on the left side, right side, and / or rear of the moving body 100. In addition, the number of such electronic devices 1 may be any number of one or more depending on various conditions (or requirements) such as the range and / or accuracy of measurement in the moving body 100. The electronic device 1 may be installed inside the moving body 100. The inside of the moving body 100 may be, for example, a space in a bumper, a space in a body, a space in a headlight, or a driving space.

[0023] The electronic device 1 transmits electromagnetic waves as transmission waves from a transmission antenna. For example, if a specific object (e.g., object 200 shown in FIG. 1) is present around the moving body 100, at least a part of the transmission wave 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 a receiving antenna of the electronic device 1, the electronic device 1 mounted on the moving body 100 can detect the object as a target.

[0024] The electronic device 1 equipped with a transmitting antenna may typically be a radar (Radio Detecting and Ranging (RADAR)) sensor that transmits and receives radio waves. However, the electronic device 1 is not limited to a radar sensor. The electronic device 1 according to an embodiment may be a sensor based on, for example, a light wave LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) technology. Such sensors may include, for example, a patch antenna. Technologies such as RADAR and LIDAR are already known, so a more detailed description may be appropriately simplified or omitted.

[0025] The electronic device 1 mounted on the moving body 100 shown in FIG. 1 receives, from a receiving antenna, a reflected wave of a transmission wave transmitted from a transmitting antenna. In this way, the electronic device 1 can detect a predetermined object 200 existing within a predetermined distance from the moving body 100 as a target. For example, as shown in FIG. 1, the electronic device 1 can measure a distance L between the moving body 100, which is the own vehicle, and the predetermined object 200. The electronic device 1 can also measure the relative speed between the moving body 100, which is the own vehicle, and the predetermined object 200. Furthermore, the electronic device 1 can also measure the direction (arrival angle θ) in which the reflected wave from the predetermined object 200 arrives at the moving body 100, which is the own vehicle.

[0026] Here, the object 200 may be, for example, at least one of an oncoming vehicle traveling in a lane adjacent to the moving body 100, an automobile traveling parallel to the moving body 100, and an automobile before or after the moving body 100 traveling in the same lane. The object 200 may also be any object present around the moving body 100, such as a motorcycle, a bicycle, a baby stroller, a human being such as a pedestrian, an animal, an insect, or other living organism, a guardrail, a median strip, a road sign, a step on a sidewalk, a wall, a manhole, or an obstacle. Furthermore, the object 200 may be moving or stationary. For example, the object 200 may be an automobile parked or stopped around the moving body 100.

[0027] 1, the ratio between the size of the electronic device 1 and the size of the mobile object 100 does not necessarily represent the actual ratio. Also, in FIG. 1, the electronic device 1 is shown installed outside the mobile object 100. However, in one embodiment, the electronic device 1 may be installed in various positions on the mobile object 100. For example, in one embodiment, the electronic device 1 may be installed inside a bumper of the mobile object 100 so as not to be visible from the outside of the mobile object 100.

[0028] In the following, as a typical example, the transmitting antenna of the electronic device 1 will be described as transmitting radio waves in a frequency band such as millimeter waves (30 GHz or higher) or quasi-millimeter waves (for example, around 20 GHz to 30 GHz). For example, the transmitting antenna of the sensor 5 may transmit radio waves having a frequency bandwidth of 4 GHz, such as 77 GHz to 81 GHz.

[0029] 2 is a functional block diagram illustrating an example of the configuration of the electronic device 1 according to an embodiment. An example of the configuration of the electronic device 1 according to an embodiment will be described below.

[0030] When measuring distances and the like using a millimeter wave radar, a frequency modulated continuous wave radar (hereinafter, referred to as FMCW radar) is often used. In an FMCW radar, a transmission signal is generated by sweeping the frequency of radio waves to be transmitted. Therefore, in a millimeter wave FMCW radar using radio waves in a frequency band of, for example, 79 GHz, the frequency of the radio waves used has a frequency bandwidth of 4 GHz, for example, 77 GHz to 81 GHz. A radar in the 79 GHz frequency band has a feature that the available frequency bandwidth is wider than other millimeter wave / quasi-millimeter wave radars in frequency bands of, for example, 24 GHz, 60 GHz, and 76 GHz. Hereinafter, such an embodiment will be described as an example.

[0031] As shown in FIG. 2, the electronic device 1 according to the embodiment includes a signal processing unit 10. The signal processing unit 10 may include a signal generation processing unit 11, a reception signal processing unit 12, and a communication interface 13. The electronic device 1 according to the embodiment includes a transmission DAC 21, a transmission circuit 22, a millimeter wave transmission circuit 23, a phase control unit 24, and a transmission antenna array 25 as a transmission unit. The electronic device 1 according to the embodiment includes a reception antenna array 31, a mixer 32, a reception circuit 33, and a reception ADC 34 as a reception unit. The electronic device 1 according to the embodiment may not include at least one of the functional units shown in FIG. 2, or may include a functional unit other than the functional unit shown in FIG. 2. The electronic device 1 shown in FIG. 2 may be configured using a circuit basically configured similarly to a general radar using electromagnetic waves such as a millimeter wave band. On the other hand, in the electronic device 1 according to the embodiment, the signal processing by the signal processing unit 10 includes processing different from that of a conventional general radar.

[0032] The signal processing unit 10 included in the electronic device 1 according to an embodiment can control the operation of the entire 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 CPU (Central Processing Unit) or a DSP (Digital Signal Processor), to provide control and processing power for executing various functions. The signal processing unit 10 may be realized as one processor, several processors, or individual processors. The processor may be realized as a single integrated circuit. The integrated circuit is also called an IC (Integrated Circuit). The processor may be realized as a plurality of integrated circuits and discrete circuits connected to each other so as to be able to communicate with each other. The processor may be realized 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 include a memory required for the operation of the signal processing unit 10 as appropriate.

[0033] 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 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 (linear chirp signal) whose frequency changes periodically and linearly. 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. Also, for example, the signal generation processing unit 11 may generate a signal whose frequency periodically repeats a linear increase (up chirp) and decrease (down chirp) from 77 GHz to 81 GHz over time. The signal generated by the signal generation processing unit 11 may be set in advance in, for example, the signal processing unit 10. Also, the signal generated by the signal generation processing unit 11 may be stored in advance in, for example, a storage unit of the signal processing unit 10. Since chirp signals used in technical fields such as radar are known, a more detailed description will be appropriately simplified or omitted. The signal generated by the signal generating and processing unit 11 is supplied to the transmitting DAC 21. For this reason, the signal generating and processing unit 11 may be connected to the transmitting DAC 21.

[0034] The transmission DAC (digital-analog converter) 21 has a function of converting the digital signal supplied from the signal generating processing unit 11 into an analog signal. The transmission DAC 21 may be configured to include a general digital-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.

[0035] The transmission circuit 22 has a function of converting the signal converted into an analog signal 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.

[0036] 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. The signal processed by the millimeter wave transmission circuit 23 is supplied to the phase control unit 24. Therefore, the millimeter wave transmission circuit 23 may be connected to the phase control unit 24. The signal processed by the millimeter wave transmission circuit 23 is also supplied to the mixer 32. Therefore, the millimeter wave transmission circuit 23 may also be connected to the mixer 32.

[0037] The phase control unit 24 controls (adjusts) the phase of the transmission signal supplied from the millimeter wave transmission circuit 23. Specifically, the phase control unit 24 may adjust the phase of the transmission signal by appropriately advancing or delaying the phase of the signal supplied from the millimeter wave transmission circuit 23 based on the control by, for example, the signal processing unit 10 or the like. In this case, the phase control unit 24 may adjust the phase of each transmission signal based on the path difference of each transmission wave T transmitted from a plurality of transmission antennas (transmission antenna array 25). By the phase control unit 24 appropriately adjusting the phase of each transmission signal, the transmission waves T transmitted from the transmission antenna array 25 reinforce each other in a predetermined direction to form a beam (beamforming). In this case, the correlation between the direction of beamforming and the phase amount to be controlled of the transmission signal transmitted by each of the plurality of transmission antennas constituting the transmission antenna array 25 may be stored in, for example, an arbitrary memory. The phase control unit 24 may be configured to include, for example, an arbitrary phase shifter. The transmission signal phase-controlled by the phase control unit 24 may be supplied to the transmission antenna array 25. Furthermore, the phase control section 24 may be placed at any appropriate position, not just at the rear stage of the millimeter wave transmission circuit 23. For example, the phase control section 24 may be placed inside the signal generation processing section 11, and phases corresponding to a plurality of transmission antennas may be added to the transmission signal in advance.

[0038] The transmitting antenna array 25 is an array of a plurality of transmitting antennas. In Fig. 2, the configuration of the transmitting antenna array 25 is shown in a simplified form. The transmitting antenna array 25 transmits a signal processed by the millimeter wave transmitting circuit 23 and phase-controlled by the phase control unit 24 to the outside of the electronic device 1. The transmitting antenna array 25 may be configured to include a transmitting antenna array used in a general millimeter wave radar.

[0039] In this manner, the electronic device 1 according to the embodiment includes a transmitting antenna (transmitting antenna array 25), and can transmit a transmitting signal (for example, a transmitting chirp signal) from the transmitting antenna array 25 as a transmitting wave.

[0040] 2, it is assumed that an object 200 is present around the electronic device 1. In this case, at least a part of the transmission wave transmitted from the transmitting antenna array 25 is reflected by the object 200. At least a part of the transmission wave transmitted from the transmitting antenna array 25 and reflected by the object 200 may be reflected toward the receiving antenna array 31.

[0041] The receiving antenna array 31 receives the reflected wave. Here, the reflected wave may be at least a part of the transmission wave transmitted from the transmitting antenna array 25 that is reflected by the object 200.

[0042] The receiving antenna array 31 is an array of multiple receiving antennas. In Fig. 2, the configuration of the receiving antenna array 31 is shown in a simplified form. The receiving antenna array 31 receives reflected waves of the transmission waves transmitted from the transmitting antenna array 25. 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 a reception 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.

[0043] 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 typical millimeter wave radar. The mixer 32 supplies a signal generated as a result of the synthesis to the reception circuit 33. For this reason, the mixer 32 may be connected to the reception circuit 33.

[0044] 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.

[0045] The receiving ADC (analog-digital converter) 34 has a function of converting an analog signal supplied from the receiving circuit 33 into a digital signal. The receiving ADC 34 may be configured to include a general analog-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.

[0046] The reception signal processing unit 12 of the signal processing unit 10 has a function of performing various processes on the digital signal supplied from the reception DAC 34. For example, the reception signal processing unit 12 calculates 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 also calculates 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 calculates 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). 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. Thereafter, the reception signal processing unit 12 suppresses false alarms by removing noise points through processing such as CFAR (Constant False Alarm Rate) and sets a constant probability. The received signal processor 12 then performs arrival angle estimation for points that satisfy the CFAR criteria, thereby obtaining the position of the object 200. Information generated as a result of distance, speed, and angle measurement by the received signal processor 12 may be supplied to a communication interface 13. The signal processor 10 may also use a universal asynchronous receiver transmitter (UART) as an interface for data transmission.

[0047] The communication interface 13 of the signal processing unit 10 includes an interface that outputs information of the signal processing unit 10 to, for example, an external device. The communication interface 13 may output at least one of information on the position, speed, and angle of the object 200 to the outside of the signal processing unit 10 as a signal such as a CAN (Controller Area Network). At least one of information on the position, speed, and angle of the object 200 is supplied to the outside of the electronic device 1 via the communication interface 13. In addition, the communication interface 13 may supply the result of the object being detected by the signal processing unit 10 (detection result) to the outside of the electronic device 1.

[0048] 2, the electronic device 1 according to an embodiment may output a detection result by a signal processing unit 10 to an external device such as an ECU (Electronic Control Unit). Here, the external device may control various operations of a moving object 100, for example. In this case, the external device may be configured by at least one ECU.

[0049] FIG. 3 is a diagram for explaining an example of a chirp signal generated by the signal generation processing unit 11 of the signal processing unit 10. In FIG.

[0050] FIG. 3 shows the time structure of one frame when the FCM (Fast-Chirp Modulation) method is used. 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 short intervals (for example, longer than the round-trip time between the electromagnetic 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 it into subframe units as shown in FIG. 3.

[0051] In Fig. 3, the horizontal axis represents the elapsed time, and the vertical axis represents the frequency. In the example shown in Fig. 3, the signal generation processing unit 11 generates a linear chirp signal whose frequency changes periodically and linearly. In Fig. 3, each chirp signal is shown as c1, c2, c3, c4, ..., cn. As shown in Fig. 3, in each chirp signal, the frequency increases linearly with the passage of time.

[0052] In the example shown in FIG. 3, several chirp signals such as c1, c2, c3, c4, ..., cn are included to form one subframe. That is, subframe 1 and subframe 2 shown in FIG. 3 are each configured to include 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 to form one frame (1 frame). That is, one frame shown in FIG. 3 is configured to include 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 configured to include N subframes, similar to frame 1. Also, a frame interval of a predetermined length may be included between the frames. One frame shown in FIG. 3 may be, for example, about 30 milliseconds to 50 milliseconds long.

[0053] In the electronic device 1 according to an embodiment, the signal generation processing unit 11 may generate a transmission signal as an arbitrary number of frames. Also, some chirp signals are omitted in Fig. 3. In this manner, the relationship between the time and frequency of the transmission signal generated by the signal generation processing unit 11 may be stored in, for example, a storage unit of the signal processing unit 10.

[0054] In this manner, the electronic device 1 according to an embodiment may transmit a transmission signal consisting of subframes including a plurality of chirp signals. Also, the electronic device 1 according to an embodiment may transmit a transmission signal consisting of a frame including a predetermined number of subframes.

[0055] Hereinafter, the electronic device 1 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 an example, and for example, the chirp signal included in one subframe may be arbitrary. That is, in one embodiment, the signal generation processing unit 11 may generate a subframe including an arbitrary number (for example, an arbitrary multiple) of chirp signals. Also, the subframe structure as shown in FIG. 3 is an example, and for example, the subframe included in one frame may be arbitrary. That is, in one embodiment, the signal generation processing unit 11 may generate a frame including an arbitrary number (for example, an arbitrary multiple) of subframes. The signal generation processing unit 11 may generate signals of different frequencies. The signal generation processing unit 11 may generate a plurality of discrete signals having different bandwidths of frequency f.

[0056] Fig. 4 is a diagram showing, in another aspect, a part of the subframe shown in Fig. 3. Fig. 4 shows each sample of a received signal obtained by receiving the transmission signal shown in Fig. 3 as a result of performing 2D-FFT (Two Dimensional Fast Fourier Transform), which is processing performed in the received signal processing unit 12 (Fig. 2) of the signal processing unit 10.

[0057] 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 represented by squares arranged in the horizontal direction. The received signal shown in Fig. 4 is subjected to 2D-FFT, CFAR, and integrated signal processing of each subframe in the received signal processing unit 12 shown in Fig. 2.

[0058] FIG. 5 is a diagram showing an example in which a group of points on a range-Doppler (distance-velocity) plane is calculated 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. 2.

[0059] In FIG. 5, the horizontal direction represents range (distance), and the vertical direction represents velocity. The filled point cloud s1 shown in FIG. 5 is a point cloud indicating signals that exceed a threshold in CFAR processing. The unfilled point cloud s2 shown in FIG. 5 indicates a bin (2D-FFT sample) without a point cloud that does not exceed a threshold in CFAR processing. For the point cloud on the range-Doppler plane calculated in FIG. 5, the direction from the radar is calculated by direction estimation, and the position and velocity on a two-dimensional plane are calculated as a point cloud indicating the object 200. Here, the direction estimation may be calculated by a beamformer and / or a subspace method. Representative algorithms of the subspace method include MUSIC (MUltiple SIgnal Classification) and ESPRIT (Estimation of Signal Parameters via Rotation Invariance Technique).

[0060] Fig. 6 is a diagram showing an example of the result of the reception signal processing unit 12 converting the point cloud coordinates from the range-Doppler plane shown in Fig. 5 to the XY plane after performing direction estimation. As shown in Fig. 6, the reception signal processing unit 12 can plot the point cloud PG on the XY plane. Here, the point cloud PG is composed of each point P. Furthermore, each point P has an angle θ and a radial velocity Vr in polar coordinates.

[0061] The reception signal processing unit 12 detects an object present in the range where the transmission wave T is transmitted based on at least one of the results of the 2D-FFT and the angle estimation. The reception signal processing unit 12 may perform object detection by, for example, clustering processing based on the estimated distance information, speed information, and angle information. As an algorithm used for clustering (grouping) data, for example, DBSCAN (Density-based spatial clustering of applications with noise) is known. This is an algorithm for performing clustering based on density. In the clustering processing, for example, the average power of points constituting the detected object may be calculated. The distance information, speed information, angle information, and power information of the object detected by the reception signal processing unit 12 may be supplied to, for example, an external device. In this case, when the moving body 100 is an automobile, communication may be performed via a communication interface 13 such as a CAN (Controller Area Network).

[0062] As described above, the electronic device 1 may include a transmitting antenna (transmitting antenna array 25), a receiving antenna (receiving antenna array 31), a signal processing unit 10, and a phase control unit 24. The transmitting antenna (transmitting antenna array 25) transmits a transmitting wave T. The receiving antenna (receiving antenna array 31) receives a reflected wave R resulting from reflection of the transmitting wave T. The phase control unit 24 also controls the radiation pattern of the transmitting wave transmitted by the transmitting antenna array 25. For example, the phase control unit 24 may control (change) the phase of the transmitting wave transmitted by at least one of the transmitting antennas included in the transmitting antenna array 25. Then, the signal processing unit 10 detects an object (such as the object 200) that reflects the transmitting wave T around the electronic device 1 based on the transmitting signal transmitted as the transmitting wave T and the receiving signal received as the reflected wave R.

[0063] Next, in describing the operation of the electronic device 1 according to an embodiment, first, object detection using general radar technology or the like will be considered.

[0064] The electronic device 1 according to an embodiment may detect an object reflecting a transmission wave in the vicinity of the electronic device 1 by receiving a reflected wave of the transmission wave once. Here, receiving the reflected wave "once" may mean receiving one unit (e.g., one frame) of a predetermined radiation pattern of radio waves emitted from a transmitting antenna, for example, in the case of a millimeter wave radar. In this case, one unit of a predetermined radiation pattern of radio waves may have the same radiation pattern as the next unit. The same may be true for the subsequent units. Such object detection processing is employed in many situations, for example, in millimeter wave radar.

[0065] In relation to object detection using millimeter wave radar technology, problems such as non-detection (false negative) and false positive are generally known. Here, non-detection may mean not detecting an object that is desired to be detected, and false positive may mean detecting an object that is not desired to be detected. If the sensitivity of the radar sensor is lowered too much, a problem of non-detection may occur, whereas if the sensitivity of the radar sensor is increased too much, a problem of false positive may occur. Thus, the problem of false positive is in a trade-off relationship with the detection rate of the object.

[0066] Generally, when detecting an object using a radar sensor such as a millimeter wave radar, the detection signal contains noise (noise points). As described above, even when detecting a target object by receiving a single reflected wave of a transmitted wave, noise may occur depending on the surrounding environment. Possible causes of such noise include, for example, the presence of an object that is not desired to be detected as a target, the effect of multipath, and / or the specifications (characteristics) of the radar sensor. For example, if a reflected wave reflected from a target object is further reflected from other objects and propagates along multiple paths (multipath), a problem may occur in which one object is detected as multiple objects.

[0067] When the above-mentioned noise occurs in a radar sensor, it may affect processes such as clustering, leading to a decrease in the accuracy of detecting an object. For example, the above-mentioned noise may affect processes such as the above-mentioned DBSCAN, which are executed when detecting an object.

[0068] For example, in clustering such as DBSCAN, noise points that are somewhat distant from a certain cluster are not included in the cluster. Therefore, when calculating a representative point of a point group included in the cluster, the noise points do not affect the position of the representative point. Here, the representative point of a point group included in a cluster may be based on various calculation methods, such as a point calculated as the average value of the X coordinate and the average value of the Y coordinate of each point included in the point group (cluster). On the other hand, noise points that are not somewhat distant from a certain cluster may be included in the cluster. Therefore, when calculating a representative point of a point group included in the cluster, the noise points may affect the position of the representative point. In this way, when clustering such as normal DBSCAN is performed, the position of the representative point of a certain cluster may be affected by the noise points. Therefore, in normal clustering, the detection accuracy of an object may decrease due to the influence of the noise points.

[0069] Therefore, in consideration of the above-mentioned situation, the electronic device 1 according to an embodiment takes measures to improve the detection accuracy of an object. For this purpose, the electronic device 1 according to an embodiment first (1) transmits a transmission wave from a transmission antenna multiple times, including a transmission in which the radiation pattern of the transmission wave is slightly changed in a relatively short time. Here, "changing the radiation pattern of the transmission wave" may include changing the phase of the transmission wave. Then, the electronic device 1 according to an embodiment (2) selects a suitable point group (or excludes an unsuitable point group) and calculates a detection result when performing signal processing based on the reflected wave received multiple times. This allows the electronic device 1 according to an embodiment to improve the detection accuracy of an object. Therefore, the electronic device 1 according to an embodiment can detect an object well. Hereinafter, such an embodiment will be further described.

[0070] First, we will explain item (1) above.

[0071] An electronic device 1 according to an embodiment transmits a transmission wave multiple times in succession, for example, in units of one frame (or one subframe), as shown in Fig. 3. In this way, the transmission wave transmitted in units of one frame (or one subframe) is reflected by an object to become a reflected wave. Therefore, the electronic device 1 according to an embodiment detects an object by receiving each of the reflected waves resulting from the transmission wave being reflected multiple times in succession, for example, in units of one frame (or one subframe).

[0072] Here, when transmitting a transmission wave multiple times in succession in units of one frame, etc., let us assume that the radiation pattern of each transmission wave is not changed (i.e., transmission waves with the same radiation pattern are transmitted multiple times. In this case, even if the transmitted wave is reflected multiple times in succession and the reflected waves are received, there is almost no change in each reflected wave, and it is expected that the detection result will be almost the same.

[0073] On the other hand, the electronic device 1 according to an embodiment may change the radiation pattern of at least one of the transmission waves when transmitting the transmission waves in units of one frame or the like multiple times in succession. This allows the electronic device 1 according to an embodiment to detect the same object multiple times as having different features from different viewpoints. When changing the radiation pattern of the transmission wave, the phase control unit 24 of the electronic device 1 may, for example, change the phase of the transmission wave transmitted by at least one of the transmission antennas included in the transmission antenna array 25.

[0074] For example, when transmitting waves of the same phase (in-phase) from all transmitting antennas included in the transmitting antenna array 25, the transmitting waves propagate in a direction perpendicular to the direction in which the transmitting antennas are arranged in an array (referred to as a straight direction). In this case, the wavefront of the transmitting wave is parallel to the direction in which the transmitting antennas are arranged in an array. In other words, the radiation direction of the transmitting wave is perpendicular to the direction in which the transmitting antennas are arranged in an array.

[0075] On the other hand, if the phase of the transmission wave transmitted from at least one of the transmitting antennas included in the transmitting antenna array 25 is slightly different from the phase of the transmission wave transmitted from the other transmitting antennas, the transmission wave propagates in a direction slightly shifted from the straight traveling direction. In this case, the wavefront of the transmission wave is not parallel to the direction in which the transmitting antennas are arranged in an array. In other words, the radiation direction of the transmission wave is not perpendicular to the direction in which the transmitting antennas are arranged in an array.

[0076] The radiation direction of the transmission waves changes because the difference in phase of the transmission waves transmitted from the multiple transmission antennas causes a difference in the distance the transmission waves propagate. The difference in phase of the transmission waves transmitted from the multiple transmission antennas may be controlled as a difference in the timing of transmitting the transmission waves.

[0077] As described above, when a plurality of transmission waves with different radiation patterns are reflected by an object, the electronic device 1 can receive the reflected waves reflected by the object as different reflected waves. In this way, the electronic device 1 according to an embodiment can detect the object from a plurality of viewpoints by utilizing the fact that the reflected waves reflected by the same object may be different by changing the radiation pattern of the transmission wave. For example, even if the object is the same, it may be recognized as visually different images if the direction of the irradiated light is different. Based on a principle similar to this phenomenon, the electronic device 1 according to an embodiment may detect the same object in different ways by changing the mode of the transmitted transmission wave.

[0078] In this way, in the electronic device 1 according to an embodiment, the phase control unit 24 may control the transmission wave to include at least one transmission wave with a changed radiation pattern when the transmission wave is transmitted multiple times in a predetermined unit. For example, in the electronic device 1 according to an embodiment, the phase control unit 24 may control the transmission wave to include at least one transmission wave with a changed phase when the transmission wave is transmitted multiple times in a predetermined unit. In this case, the phase control unit 24 may control (change) the phase of the transmission wave transmitted by at least one of the transmission antennas included in the transmission antenna array 25.

[0079] In one embodiment, the phase control unit 24 may control the transmission wave with the changed radiation pattern to include more than one, i.e., two or more, times. In one embodiment, the phase control unit 24 may control the transmission wave to change the radiation pattern every time. Such a change in the radiation pattern may be the same minute change every time, may include different minute changes, or may be a minute change that is randomly different every time, for example.

[0080] As described above, the electronic device 1 according to the embodiment changes the radiation direction of the transmission wave by changing the phase of the transmission wave transmitted by at least one of the transmission antennas included in the transmission antenna array 25. In this case, if the radiation direction of the transmission wave is changed significantly, the transmission wave may not be reflected by the same object but may be reflected by different objects. That is, in this case, different objects may be detected by the transmission wave transmitted multiple times. For this reason, the electronic device 1 according to the embodiment may be configured so that the radiation direction of the transmission wave does not change significantly beyond a predetermined value when changing the phase of the transmission wave transmitted by at least one of the transmission antennas included in the transmission antenna array 25. The allowable value for changing the radiation direction of the transmission wave may be variously defined depending on the detection target and / or environment. As an example, the allowable value for changing the radiation direction of the transmission wave may be in the range of 1° to 3°. Also, as an example, the allowable value for changing the radiation direction of the transmission wave may be in the range of 0.5° to 5°. Furthermore, as an example, the allowable value for changing the radiation direction of the transmission wave may be in the range of up to a dozen degrees. In this manner, in the electronic device 1 according to one embodiment, the phase control unit 24 may change the phase of the transmission wave so that the change in the radiation direction of the transmission wave is, for example, greater than or equal to 1° and less than or equal to 15°.

[0081] In this way, when changing the transmission pattern or phase of the transmission wave, it may be changed, for example, by a predetermined small amount from the default value, or it may be changed, for example, by a random small amount each time from the default value.

[0082] Furthermore, when the electronic device 1 according to an embodiment transmits the transmission wave multiple times in a predetermined unit as described above, the transmission wave may be transmitted multiple times in a short time such as one frame. By transmitting the transmission wave multiple times in a relatively short time such as 50 ms, it is possible to detect an object to be detected before it moves significantly. In this way, the electronic device 1 according to an embodiment may transmit the transmission wave multiple times in one frame in a predetermined unit. For example, in a simple case, a transmission wave that constitutes one unit in one frame may be transmitted multiple times.

[0083] Next, we will explain item (2) above.

[0084] In the above item (2), the electronic device 1 according to an embodiment executes signal processing based on the reflected wave received multiple times. In this signal processing, the electronic device 1 according to an embodiment executes processing for reducing noise.

[0085] 7 and 8 are flowcharts for explaining the operation of the electronic device 1 according to one embodiment. FIG. 7 shows the operation from the transmission of a transmission wave by the electronic device 1 to the preliminary processing for performing signal processing for object detection. Also, FIG. 8 shows the object detection processing according to one embodiment, which is performed based on the result of the preliminary processing shown in FIG. 7. Hereinafter, the operation of the electronic device 1 according to one embodiment will be explained with reference to FIG. 7 and FIG. 8.

[0086] 7 starts, the electronic device 1 according to one embodiment transmits a transmission wave having different radiation patterns multiple times as described above (step S11). In step S11, the electronic device 1 changes the radiation pattern (phase) of the transmission wave and transmits the transmission wave multiple times in a short period of time such as one frame. The operation in step S11 has already been described, so a detailed description will be omitted.

[0087] When a transmission wave is transmitted in step S11, the electronic device 1 receives a reflected wave (step S12). In step S11, the electronic device 1 transmits the transmission wave multiple times. Therefore, in step S12, the electronic device 1 receives the reflected wave, which is the transmission wave reflected by an object, multiple times.

[0088] When the reflected wave is received in step S12, the signal processing unit 10 of the electronic device 1 performs clustering on the received signals based on the reflected wave, i.e., the detection results of the object (step S13). The clustering performed in step S13 may be, for example, the above-mentioned DBSCAN, but is not limited thereto. For convenience of explanation, the following description will be given assuming that DBSCAN is performed as the clustering in step S13. The process in step S13 may be executed by, for example, the received signal processing unit 12 of the signal processing unit 10. The same applies to the processes after step S13. In step S13, the signal processing unit 10 may perform a clustering calculation on each of the received signals received multiple times, i.e., each of the detection results multiple times.

[0089] After the clustering is performed in step S13, the signal processing unit 10 judges whether or not the clusters are detected a predetermined number of times or more by the clustering (step S14). For example, if no clusters are detected in the first detection, but clusters are detected in the second and third detections, the signal processing unit 10 may determine in step S14 that the clusters have been detected twice. Also, in step S14, the signal processing unit 10 may judge whether or not the clusters have been detected a predetermined number of times or more required for subsequent processing. Here, the subsequent processing may be, for example, processing to remove the influence of noise points, as described later in FIG. 8. In step S14, the signal processing unit 10 may judge whether or not the clusters have been detected, for example, twice or more.

[0090] If the cluster is not detected the predetermined number of times or more in step S14, the signal processing unit 10 may end the operation shown in Fig. 7. On the other hand, if the cluster is detected the predetermined number of times or more in step S14, the signal processing unit 10 may execute the process of the next step S15.

[0091] In step S15, the signal processing unit 10 calculates representative points of the clustered clusters and calculates distances between these representative points (step S15). Here, the representative points of the clusters may be the "representative points of the points included in the clusters" described above. That is, the representative points of the clusters may be calculated based on various calculation methods, such as a point calculated as the average value of the X coordinates and the average value of the Y coordinates of each point included in the point cloud (cluster). Also, in step S15, if there are multiple detection results due to receiving the reflected wave multiple times, multiple representative points of the clusters are also calculated. Then, in step S15, the signal processing unit 10 calculates the distances between the representative points of multiple clusters.

[0092] For example, the signal processing unit 10 may calculate the distance between the representative point of the cluster based on the first detection and the representative point of the cluster based on the second detection. Similarly, the signal processing unit 10 may calculate the distance between the representative point of the cluster based on the first detection and the representative point of the cluster based on the third detection. Similarly, the signal processing unit 10 may calculate the distance between the representative point of the cluster based on the second detection and the representative point of the cluster based on the third detection. In step S15, the signal processing unit 10 may calculate the distance between the representative points for all of the representative points of the multiple clusters.

[0093] After the distances between the representative points of the clusters are calculated in step S15, the signal processing unit 10 judges whether these distances are smaller than a predetermined threshold value (step S16). In step S16, it is judged whether these clusters belong to the same group. For this reason, the predetermined threshold value in step S16 may be a distance that can be assumed to belong to the same group, such as 1 m.

[0094] If the distance between the representative points is smaller than a predetermined threshold in step S16, the signal processing unit 10 determines that the clusters corresponding to these representative points are in the same group (step S17). Here, the clusters in the same group may be the result of these clusters (point clouds) detecting the same object. On the other hand, if the distance between the representative points is not smaller than the predetermined threshold in step S16, the signal processing unit 10 determines that the clusters corresponding to these representative points are not in the same group, that is, they are different groups (step S18). Here, the clusters in different groups may be the result of these clusters (point clouds) detecting different objects, not the result of the same object.

[0095] 7 may be repeatedly executed, for example, in units of one frame (or one subframe) of a transmission wave. In addition, in one embodiment, the operations from step S11 to step S13 described above may be looped. That is, in one embodiment, the electronic device 1 may repeat an operation required times to detect an object using a transmission wave with a certain radiation pattern, perform clustering, and detect an object using a transmission wave with a changed radiation pattern, perform clustering. In this case, the result of clustering may be stored in an arbitrary memory in the signal processing unit 10, for example.

[0096] Also, instead of the above-mentioned operations from step S15 to step S18, the signal processing unit 10 may determine whether the clusters belong to the same group by further performing clustering such as DBSCAN on the representative points of the multiple clusters. That is, in this case, the signal processing unit 10 may treat the representative points of the clusters corresponding to each of the multiple detection results as a new point cloud, and perform clustering such as DBSCAN on this point cloud.

[0097] As described above, the operations shown in FIG. 8 may be executed after the operations shown in FIG. 7 are completed (or each time the operations shown in FIG. 7 are completed).

[0098] When the operation shown in Fig. 8 starts, the signal processing unit 10 calculates the area of ​​the range in which the point cloud is distributed in each of the multiple clusters determined to be in the same group in step S17 in Fig. 7 (step S21). Hereinafter, the area of ​​the range in which the point cloud is distributed in a certain cluster is also referred to as the "point cloud distribution area" as appropriate.

[0099] For example, assume that four clusters, cluster A, cluster B, cluster C, and cluster D, are determined to be in the same group in step S17 in Fig. 7. In this case, in step S21, the signal processing unit 10 calculates the point cloud distribution area of ​​each of the four clusters, cluster A, cluster B, cluster C, and cluster D.

[0100] After the point cloud distribution area of ​​each of the multiple clusters is calculated in step S21, the signal processing unit 10 outputs the representative point of the cluster with the smallest point cloud distribution area (step S22). Hereinafter, the cluster with the smallest point cloud distribution area in step S21 may be referred to as the "selected cluster." For example, in the above case, it is assumed that the point cloud distribution area of ​​cluster C is the smallest. In this case, in step S22, the signal processing unit 10 calculates and outputs the representative point of cluster C as the selected cluster. In this way, the output calculated in step S22 may be the detection result output from the electronic device 1.

[0101] Furthermore, the representative point of the detection target cluster output in step S22 may be an average value, a median value, a minimum value, a maximum value, or the like calculated from the representative points of the selected cluster. For example, the representative point of the detection target cluster output in step S22 may be a point calculated as, for example, the average value of the X coordinate and the average value of the Y coordinate of each point included in the selected cluster. For example, the representative point of the detection target cluster output in step S22 may be a point calculated as, for example, the average value of the X coordinate and the median value of the Y coordinate of each point included in the selected cluster. In this way, the signal processing unit 10 may output any one of the average value, median value, minimum value, or maximum value of the representative points of the selected cluster as the object detection result.

[0102] In this manner, in the electronic device 1 according to an embodiment, the signal processing unit 10 may select the cluster with the smallest area in which the point cloud is distributed as the selected cluster among the multiple clusters obtained by performing clustering on each of the results of detecting the object multiple times. Also, in the electronic device 1 according to an embodiment, the signal processing unit 10 may output the object detection result based on the selected cluster.

[0103] As described above, in the electronic device 1 according to an embodiment, the signal processing unit 10 may execute the process shown in Fig. 8 using clusters belonging to the same group among the multiple clusters, as shown in steps S14 to S18 in Fig. 7. In this manner, the signal processing unit 10 may select a selected cluster from among the multiple clusters obtained by performing clustering on each of the results of detecting an object multiple times, the clusters having representative points within a predetermined distance from each other.

[0104] For example, in step S17 of FIG. 7, it is assumed that the clusters shown in (1) to (3) of FIG. 9 are determined to belong to the same group. For example, the cluster shown in (1) of FIG. 9 is the result of clustering based on the reflected wave received the first time. Similarly, the cluster shown in (2) of FIG. 9 is the result of clustering based on the reflected wave received the second time. Moreover, the cluster shown in (3) of FIG. 9 is the result of clustering based on the reflected wave received the third time. Moreover, in the clusters shown in (1) to (3) of FIG. 9, the black dots indicate points or point groups included in each cluster. Meanwhile, in the clusters shown in (1) to (3) of FIG. 9, the white dots indicate the representative points of each cluster.

[0105] In FIG. 9, the cluster shown in (1) and the cluster shown in (3) have almost the same point cloud distribution area. On the other hand, in FIG. 9, the point cloud distribution area of ​​the cluster shown in (2) is smaller than the point cloud distribution area of ​​the cluster shown in (1) and the cluster shown in (3). In this case, the cluster shown in (2) becomes the selected cluster. Therefore, the object detection result is calculated based on the cluster shown in FIG. 9 (A). The cluster shown in FIG. 9 (A) may be the selected cluster, that is, the cluster shown in (2). In this case, the electronic device 1 may output the representative point of the cluster shown in FIG. 9 (A), that is, the representative point of the selected cluster (2), as the object detection result. A method for generating the cluster shown in FIG. 9 (A) will be further described. In this disclosure, the cluster shown in (2) is selected, and the cluster shown in (A) is output as the final result, for example, the average value or median value of the representative points of the cluster shown in (2). In this disclosure, the cluster shown in (2) is actually detected by multiple transmissions and receptions, and the cluster shown in (A) is calculated.

[0106] The calculation method in the present disclosure may be, for example, a method of calculating the average value or median value of the representative points (open dots) of the cluster shown in (2). In the present disclosure, the average value or median value of all corresponding point groups (black dots) of the cluster shown in (2) may be calculated to generate a cluster called (A), and the average value or median value of the point group in (A) may be calculated as the representative point of (A).

[0107] In this way, the electronic device 1 according to the embodiment can improve the object detection accuracy by performing signal processing on multiple detection results. That is, the electronic device 1 according to the embodiment can remove clusters that may reduce the object detection accuracy. In this way, the electronic device 1 according to the embodiment can remove the influence of noise points.

[0108] In step S21 of FIG. 8, the signal processing unit 10 selects the cluster with the smallest point cloud distribution area as the selected cluster among the multiple clusters. However, in this case, the signal processing unit 10 may select the cluster with the smallest area of ​​the circle covering the range in which the point cloud is distributed with the position of the representative point as the selected cluster. Here, when selecting the selected cluster as described above, the same result will be obtained even if the selected cluster is the cluster with the smallest distance from the position of the representative point of each cluster to the most distant point in the point cloud included in the cluster. In other words, the same result will be obtained whether the selected cluster is the cluster with the smallest area of ​​the circle described above or the cluster with the smallest radius of the circle described above. In this way, the selected cluster may be the cluster with the smallest distance from the representative point of the point cloud included in each cluster to the most distant point in the point cloud among the multiple clusters obtained by performing clustering on each of the results of detecting an object multiple times.

[0109] Also, in step S22 of FIG. 8, the signal processing unit 10 may select a cluster excluding the cluster with the largest point cloud distribution area from among the multiple clusters as a selected cluster. When there are multiple selected clusters, the signal processing unit 10 may output the object detection result based on the multiple selected clusters. Specifically, the signal processing unit 10 may output the result calculated as the average value of the X coordinate and the average value of the Y coordinate of each point included in the multiple selected clusters based on various calculation methods. Thus, in one embodiment, the signal processing unit 10 may output the object detection result based on the selected cluster excluding the cluster with the largest point cloud distribution area from among multiple clusters obtained by performing clustering on each of the results of detecting the object multiple times.

[0110] Furthermore, in this case, the selected cluster may not only exclude the cluster with the largest point cloud distribution area, but may also exclude, for example, the cluster with the second largest point cloud distribution area. Furthermore, the selected cluster may also exclude, for example, the cluster with the third largest point cloud distribution area (or up to a predetermined number thereafter). As described above, the selected cluster may not only exclude the cluster with the largest point cloud distribution area, but also the clusters with a predetermined number of point cloud distribution areas. In this way, in one embodiment, the signal processing unit 10 may output an object detection result based on the selected clusters that exclude the cluster with the largest point cloud distribution area to the cluster with the predetermined number of points among the multiple clusters.

[0111] In the above-described embodiment, when changing the radiation pattern, the phase control unit 24 controls (changes) the phase of the transmission wave. However, the electronic device 1 according to an embodiment may change not only the phase of the transmission wave but also the amplitude of the transmission wave when changing the radiation pattern.

[0112] Although the present disclosure has been described based on the drawings and examples, it should be noted that a person skilled in the art can easily make various modifications or corrections based on the present disclosure. Therefore, it should be noted that these modifications or corrections are included in the scope of the present disclosure. For example, the functions included in each functional unit can be rearranged so as not to be logically inconsistent. Multiple functional units, etc. may be combined into one or divided. Each embodiment of the present disclosure described above is not limited to being implemented faithfully to each of the embodiments described, and may be implemented by combining each feature as appropriate or omitting a part. In other words, the contents of the present disclosure can be modified and corrected in various ways by a person skilled in the art based on the present disclosure. Therefore, these modifications and corrections are included in 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 be logically inconsistent, or replaced with each functional unit, each means, each step, etc. of other embodiments. In addition, in each embodiment, multiple functional units, each means, each step, etc. can be combined into one or divided. 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 may be implemented by combining each feature or omitting some features as appropriate.

[0113] 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 control method for an apparatus such as the electronic device 1. Furthermore, for example, the above-described embodiment may be implemented as an apparatus such as the electronic device 1 and / or a program executed by an arbitrary computer.

[0114] Moreover, the electronic device 1 according to the above-mentioned embodiment has been described as including components constituting a so-called radar sensor, such as the transmitting antenna array 25 and the receiving antenna array 31. However, the electronic device according to one embodiment may be implemented as, for example, a configuration such as a 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 25 and the receiving antenna array 31. [Explanation of symbols]

[0115] 1 Electronic equipment 10 Signal Processing Section 11 Signal generation processing section 12 Receiving signal processing section 13 Communication Interface 21 Transmit DAC 22 Transmitting circuit 23 Millimeter wave transmission circuit 24 Phase control section 25 Transmitting Antenna Array 31 Receiving Antenna Array 32 Mixer 33 Receiving circuit 34 Receive ADC

Claims

1. A transmitting antenna for transmitting a transmission wave; a receiving antenna for receiving a reflected wave of the transmission wave; A control unit that controls a radiation pattern of the transmission wave; a signal processing unit that detects an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; An electronic device comprising: The control unit controls the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, the transmission wave includes at least one transmission wave having a changed radiation pattern; The signal processing unit is an electronic device that outputs a detection result of the object based on a selected cluster from among multiple clusters obtained by clustering each of the results of detecting the object multiple times, the selected cluster having the shortest distance from a representative point of a point cloud contained in each cluster to the farthest point in the point cloud.

2. A transmitting antenna for transmitting a transmission wave; a receiving antenna for receiving a reflected wave of the transmission wave; A control unit that controls a radiation pattern of the transmission wave; a signal processing unit that detects an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; An electronic device comprising: The control unit controls the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, the transmission wave includes at least one transmission wave having a changed radiation pattern; The signal processing unit outputs a detection result of the object based on a selected cluster obtained by performing clustering on each of the results of detecting the object multiple times, excluding a cluster having the largest area in which a point cloud is distributed from among multiple clusters obtained by performing clustering on each of the results of detecting the object multiple times.

3. The electronic device according to claim 2 , wherein the signal processing unit outputs the object detection result based on selected clusters obtained by excluding, from the plurality of clusters, a cluster having a largest area in which the point cloud is distributed through a cluster having a predetermined second largest area.

4. 4. The electronic device according to claim 1, wherein the control unit controls a phase of the transmission wave so that when the transmission wave is transmitted a plurality of times in a predetermined unit, the transmission wave includes at least one transmission wave with a changed phase.

5. The electronic device according to claim 4 , wherein the control unit changes a phase of the transmission wave so that a change in a radiation direction of the transmission wave falls within a predetermined range.

6. The electronic device according to claim 5 , wherein the control unit changes a phase of the transmission wave such that a change in a radiation direction of the transmission wave is between 1° and 15°.

7. The electronic device according to claim 1 , wherein the transmission wave is transmitted a plurality of times in one frame in the predetermined unit.

8. 8. The electronic device according to claim 1, wherein the signal processing unit selects the selected cluster from among a plurality of clusters obtained by performing clustering on each of the results of detecting the object multiple times, the selected cluster being from clusters whose representative points are within a predetermined distance from each other.

9. The electronic device according to claim 1 , wherein the signal processing unit outputs any one of an average value, a median value, a minimum value, and a maximum value of the representative points of the selected cluster as a detection result of the object.

10. transmitting a transmission wave by a transmitting antenna; receiving a reflected wave of the transmission wave by a receiving antenna; controlling a radiation pattern of the transmission wave; detecting an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; a step of controlling the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, at least one transmission wave having a changed radiation pattern is included; a step of outputting a detection result of the object based on a selected cluster among a plurality of clusters obtained by performing clustering on each of the results of detecting the object a plurality of times, the selected cluster being the one in which the distance from a representative point of the point cloud included in each cluster to the most distant point in the point cloud is the shortest; A method for controlling an electronic device, comprising:

11. transmitting a transmission wave by a transmitting antenna; receiving a reflected wave of the transmission wave by a receiving antenna; controlling a radiation pattern of the transmission wave; detecting an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; a step of controlling the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, at least one transmission wave having a changed radiation pattern is included; a step of outputting a detection result of the object based on a selected cluster obtained by performing clustering on each of the results of detecting the object multiple times, excluding a cluster having a largest distribution area of ​​a point cloud from among a plurality of clusters obtained by performing clustering on each of the results of detecting the object multiple times; A method for controlling an electronic device, comprising:

12. For electronic devices, transmitting a transmission wave by a transmitting antenna; receiving a reflected wave of the transmission wave by a receiving antenna; controlling a radiation pattern of the transmission wave; detecting an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; a step of controlling the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, at least one transmission wave having a changed radiation pattern is included; a step of outputting a detection result of the object based on a selected cluster among a plurality of clusters obtained by performing clustering on each of the results of detecting the object a plurality of times, the selected cluster being the one in which the distance from a representative point of the point cloud included in each cluster to the most distant point in the point cloud is the shortest; A program to execute.

13. For electronic devices, transmitting a transmission wave by a transmitting antenna; receiving a reflected wave of the transmission wave by a receiving antenna; controlling a radiation pattern of the transmission wave; detecting an object based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave; a step of controlling the transmission wave such that, when the transmission wave is transmitted a plurality of times in a predetermined unit, at least one transmission wave having a changed radiation pattern is included; a step of outputting a detection result of the object based on a selected cluster obtained by performing clustering on each of the results of detecting the object multiple times, excluding a cluster having a largest distribution area of ​​a point cloud from among a plurality of clusters obtained by performing clustering on each of the results of detecting the object multiple times; A program to execute.

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