Electronic equipment and transmission / reception systems

Abstract

To provide an electronic apparatus and a transmitting and receiving system that improve convenience in an object detection technique such as a millimeter-wave radar.SOLUTION: An electronic apparatus comprises a first receiving antenna having directivity in a first direction, and a second receiving antenna having directivity in a second direction different from the first direction. The first receiving antenna is configured such that a reception gain increases as the polarizing direction of a radio wave received through the first receiving antenna becomes closer to a first polarizing direction. The second receiving antenna is configured such that a reception gain increases as the polarizing direction of a radio wave received through the second receiving antenna becomes closer to a second polarizing direction different from the first polarizing direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an electronic device and a transmission / reception system. [Background technology]

[0002] 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.

[0003] Various applications of the above-mentioned radar-like technology have been proposed. For example, Patent Document 1 proposes an antenna configuration having a first antenna formed as an array antenna and a second antenna operable as a transmitting antenna. This antenna configuration includes a transmitting antenna with two different polarization planes connected to the same feed point. Patent Document 2 proposes a technology to improve the resolution of a radar system that detects obstacles, for example, at railroad crossings. This radar system can virtually double its distance resolution by receiving two types of polarized waves by switching between two types of receiving antennas with different polarization planes with a switch. Patent Document 3 proposes a radar unit that can operate with multiple polarized waves. Furthermore, Patent Document 4 proposes delaying one of the transmitted waves, rather than switching between horizontally and vertically polarized waves, so that the reflected waves from the target are received by the receiving antenna with a delay time. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2021-514153 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-17356 [Patent Document 3] Special Publication No. 2021-507219 [Patent Document 4] Japanese Patent Application Laid-Open No. 2010-14533 Summary of the Invention [Problem to be solved by the invention]

[0005] In technologies such as the above-mentioned radar, if the directivity of the receiving antenna could be changed to a different direction without using an RF switch, convenience could be improved in certain usage situations.

[0006] An object of the present disclosure is to provide an electronic device and a transmission / reception system that can improve convenience in object detection technology such as millimeter-wave radar. [Means for solving the problem]

[0007] An electronic device according to an embodiment includes: a first receiving antenna having directivity in a first direction; a second receiving antenna having directivity in a second direction different from the first direction; Equipped with. The first receiving antenna has a receiving gain that increases as the polarization direction of the radio wave received by the first receiving antenna approaches the first polarization direction. The second receiving antenna has a receiving gain that increases as the polarization direction of the radio wave received by the second receiving antenna approaches a second polarization direction different from the first polarization direction. the first receiving antenna is fed from a feed point on the substrate; the second receiving antenna is fed from the feed point; The feed point is connected to one feed port.

[0008] An electronic device according to an embodiment includes: a first transmitting antenna that transmits radio waves having directivity in a first direction with a first polarization; a second transmitting antenna that transmits radio waves with second polarization having directivity in a second direction different from the first direction; Equipped with. The first transmitting antenna transmits a signal in the first polarization direction using a first feeding arrangement. The second transmitting antenna transmits a signal in the second polarization direction using a second feeding arrangement. The first send The antenna is fed from a feed point on the board. The second send The antenna is fed from the feed point, The feed point is connected to one feed port.

[0009] A transmission / reception system according to an embodiment includes: It includes a transmitting device having a transmitting antenna and a receiving device having a receiving antenna. The transmitting device a first transmitting antenna that transmits radio waves having directivity in a first direction with a first polarization; a second transmitting antenna that transmits radio waves with second polarization having directivity in a second direction different from the first direction; Equipped with. The receiving device a first receiving antenna having directivity in the first direction; a second receiving antenna having directivity in the second direction; Equipped with. The first receiving antenna has a receiving gain that increases as the polarization direction of the radio wave received by the first receiving antenna approaches the first polarization direction. The second receiving antenna has a receiving gain that increases as the polarization direction of the radio wave received by the second receiving antenna approaches a second polarization direction different from the first polarization direction. the first receiving antenna is fed from a feed point on the substrate; the second receiving antenna is fed from the feed point; The feed point is connected to one feed port. [Effects of the Invention]

[0010] According to one embodiment, it is possible to provide an electronic device and a transmission / reception system that improve convenience in object detection technology such as millimeter wave radar. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating a configuration of an electronic device according to an embodiment. [Figure 2] FIG. 1 is a diagram illustrating a configuration of an electronic device according to an embodiment. [Figure 3] FIG. 2 is a diagram illustrating the directivity of an electronic device according to an embodiment. [Figure 4] FIG. 2 is a top view of an antenna of the electronic device according to the embodiment. [Figure 5] FIG. 1 is a top view of a three-dimensional polar plot of gain of an electronic device according to an embodiment. [Figure 6] 1 is a graph illustrating a plot of gain of an electronic device according to an embodiment. [Figure 7] FIG. 10 is a diagram illustrating a simulation of an operation of an electronic device according to an embodiment. [Figure 8] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 9] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 10] FIG. 10 is a diagram illustrating a simulation of an operation of an electronic device according to an embodiment. [Figure 11] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 12] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 13] FIG. 10 is a diagram illustrating a simulation of an operation of an electronic device according to an embodiment. [Figure 14] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 15] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 16] FIG. 10 is a diagram illustrating a simulation of an operation of an electronic device according to an embodiment. [Figure 17] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 18] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 19] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 20] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 21] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 22] FIG. 10 is a diagram illustrating a simulation result of an operation of an electronic device according to an embodiment. [Figure 23] 1 is a diagram illustrating a configuration of a radome of an electronic device according to an embodiment. [Figure 24] FIG. 10 is a diagram illustrating a configuration of an electronic device according to a comparative example of an embodiment. [Figure 25] FIG. 10 is a diagram illustrating a configuration of an electronic device according to a comparative example of an embodiment. [Figure 26] 10A and 10B are diagrams illustrating the directivity of an electronic device according to a comparative example of an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] In the present disclosure, an "electronic device" may refer to a device powered by electricity. An electronic device according to an embodiment may include at least one of a transmitting antenna and a receiving antenna. The electronic device according to an embodiment transmits electromagnetic waves as transmission waves from the transmitting antenna. For example, if a predetermined object is present around the electronic device according to an embodiment, at least a portion of the transmission waves transmitted from the electronic device is reflected by the object and becomes a reflected wave. The electronic device can then detect the object by receiving such a reflected wave with the receiving antenna of the electronic device. For example, the electronic device according to an embodiment can measure the distance to the predetermined object. The electronic device according to an embodiment can also measure the relative speed with respect to the predetermined object. Furthermore, the electronic device according to an embodiment can also measure the direction (arrival angle) in which the reflected wave from the predetermined object arrives at the electronic device.

[0013] An electronic device according to an embodiment can be installed in a roadside device that monitors the operation status of a vehicle (mobile body) such as an automobile, and can detect a predetermined object such as a mobile body that exists around the roadside device. Also, an electronic device according to an embodiment can be installed in any device such as a traffic light, and can detect a predetermined object such as a mobile body that exists around the device.

[0014] An electronic device according to an embodiment may typically be a radar (Radio Detecting and Ranging) sensor that transmits and receives radio waves. However, an electronic device according to an embodiment is not limited to a radar sensor. Such sensors may include, for example, a patch antenna. Since RADAR-like technologies are already known, detailed descriptions may be appropriately simplified or omitted. An electronic device according to an embodiment may employ, for example, an LED or a laser as a light source. An electronic device according to an embodiment may employ, for example, a photodiode as a light receiving element. An electronic device according to an embodiment may use, for example, a lens to control directivity.

[0015] In radar technology, there is a known method for estimating the direction of arrival (DOA) of radio waves from the phase difference of radio waves received by multiple antennas, such as an array antenna (antenna array). Examples of such DOA estimation methods include the MUSIC (MUltiple SIgnal Classification) method and the ESPRIT (Estimation of Signal Parameter via Rotational Invariance Techniques) method. The DOA of radio waves can be estimated with at least two antennas. However, in order to increase the angular resolution of DOA estimation (increase the array degrees of freedom (N-1, where N is the number of antennas)), the multiple receiving antennas may all be configured as array antennas of the same shape.

[0016] In order to extend the detectable distance of a radar, it is necessary to increase the antenna gain. Furthermore, to increase the antenna gain, an array antenna in which antenna elements are regularly arranged may be configured. For example, in the case of an in-vehicle corner radar, an antenna with a directivity in which the beam width is wide in the horizontal direction and narrow in the vertical direction can be configured by arranging array antennas vertically. For example, in the case of a radar for forward detection, a high-gain antenna can be configured by arranging antennas vertically and horizontally and narrowing the beam in the horizontal and vertical directions.

[0017] Conventionally, array antennas have been used that have high gain and narrow beamwidth antenna directivity by combining radio wave transmission or reception from multiple antenna elements. In such array antennas, the maximum gain, directivity direction, and beamwidth can be adjusted by controlling the number of antenna elements, the spacing between antenna elements, and the phase difference between antenna elements. One characteristic of array antennas is that increasing gain is necessary to extend the radar detection distance. On the other hand, increasing gain narrows the antenna beamwidth, thereby narrowing the detection range. Furthermore, generally, combining directivities from different directions can cause interference between antenna elements. In such antennas, the antenna characteristics cannot be calculated by simple summation. Therefore, the design of such antennas can be complex.

[0018] In a transmitting antenna, it is possible to differentiate the antenna characteristics by giving each of the multiple ports different gains, directivities, and beam widths. On the other hand, in a receiving antenna, in order to estimate the direction of arrival with high accuracy, it is necessary to make the antenna characteristics the same for all ports within a limited number of ports. As mentioned above, it is possible to estimate the direction of arrival of radio waves with at least two receiving antennas. However, it is difficult to estimate the direction of arrival with high accuracy using a two-port receiving antenna.

[0019] It is also envisioned that millimeter-wave radar installed in a relatively high place (e.g., 2.5 m or higher) such as a traffic light or a pole on which a traffic light is installed may be used to detect both long-distance and short-distance objects (e.g., automobiles and pedestrians). In such cases, it is desirable to have directivity in the front direction for detecting long-distance objects, and directivity in a downward or diagonally downward direction for detecting short-distance objects.

[0020] However, when directing the directivity downward using phase control, the gain in the forward direction decreases. This makes it difficult to ensure antenna gain in two directions with a single antenna. In such cases, it may seem possible to address the issue by switching the receiving antenna with a switch. However, RF switches compatible with the 79 GHz band are not easy to obtain. Furthermore, switching the receiving antenna with a switch degrades the noise figure (NF). Therefore, such receiving antennas are a factor in degrading the receiving sensitivity. Furthermore, when multiple antennas are installed, interference between the antennas becomes an issue.

[0021] The electronic device according to the embodiment can be used in the manner described above. Before describing the electronic device according to the embodiment, an electronic device according to a comparative example of the embodiment will be described first.

[0022] 24 and 25 are diagrams illustrating the configuration of an electronic device according to a comparative example of an embodiment. Fig. 24 is a diagram illustrating the electronic device according to the comparative example of an embodiment viewed from a predetermined direction. Fig. 25 is a diagram illustrating the electronic device according to the comparative example of an embodiment viewed from a direction opposite to the predetermined direction in Fig. 24.

[0023] 24 and 25, the X-axis direction may be the horizontal direction or the left-right direction. In FIGS. 24 and 25, the Y-axis direction may be the vertical direction or the up-down direction. In particular, in FIGS. 24 and 25, the positive Y-axis direction may be the upward direction, and the negative Y-axis direction may be the downward direction. In FIGS. 24 and 25, the Z-axis direction may be the front-to-back direction. In particular, in FIGS. 24 and 25, the positive Z-axis direction may be the forward direction or the front (front) direction, and the negative Z-axis direction may be the backward direction or the rear direction.

[0024] As shown in FIGS. 24 and 25, an electronic device 100 according to a comparative example of an embodiment may include a substrate 10′. The substrate 10′ may be a circuit board used in a normal electric circuit or electronic circuit. The surface of the substrate 10′ shown in FIG. 24 (i.e., the surface of the substrate 10′ facing the positive Z-axis direction) will also be referred to as the front surface or surface for convenience. Furthermore, the surface of the substrate 10′ shown in FIG. 25 (i.e., the surface of the substrate 10′ facing the negative Z-axis direction) will also be referred to as the back surface or backside for convenience. FIGS. 24 and 25 show functional units of the transmission system and reception system of the electronic device 100.

[0025] As shown in Fig. 24, the electronic device 100 includes a first transmitting antenna 11', a second transmitting antenna 12', and a third transmitting antenna 13' on the surface of the substrate 10'. As shown in Fig. 24, the electronic device 100 includes a receiving antenna 20' on the surface of the substrate 10'. The first transmitting antenna 11', the second transmitting antenna 12', the third transmitting antenna 13', and the receiving antenna 20' may be planar antennas (patch antennas) that are commonly used in millimeter-wave radar.

[0026] As shown in Fig. 24, the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' each include a plurality of radiating elements. These radiating elements may be made of a metal material such as copper. In the example shown in Fig. 24, the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' each include 14 radiating elements, seven on the upper side and seven on the lower side. In each of the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13', the seven radiating elements on the upper side are electrically connected in series vertically, and the seven radiating elements on the lower side are also electrically connected in series vertically.

[0027] As shown in FIG. 24, in the first transmitting antenna 11′, the lower ends of the seven series-connected radiating elements on the upper side and the upper ends of the seven series-connected radiating elements on the lower side are electrically connected to a feed point 31′. The feed point 31′ feeds power to the multiple radiating elements that make up the first transmitting antenna 11′. In the first transmitting antenna 12′, the lower ends of the seven series-connected radiating elements on the upper side and the upper ends of the seven series-connected radiating elements on the lower side are electrically connected to a feed point 32′. The feed point 32′ feeds power to the multiple radiating elements that make up the second transmitting antenna 12′. In the first transmitting antenna 13′, the lower ends of the seven series-connected radiating elements on the upper side and the upper ends of the seven series-connected radiating elements on the lower side are electrically connected to a feed point 33′. The feed point 33′ feeds power to the multiple radiating elements that make up the third transmitting antenna 13′. In each of the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13', the seven series-connected radiating elements on the upper side and the seven series-connected radiating elements on the lower side may be arranged on approximately the same straight line, as shown in Fig. 24. In this way, the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' may form an array antenna.

[0028] The feed point 31', the feed point 32', and the feed point 33' each supply power from the back surface of the substrate 10' shown in FIG. 25 to the front surface of the substrate 10' shown in FIG. 24. For this reason, the feed point 31', the feed point 32', and the feed point 33' may each be configured to include a conductor that penetrates the substrate 10' in the thickness direction. The feed point 31', the feed point 32', and the feed point 33' each supply power from the back side of the substrate 10' to the first transmitting antenna 11', the second transmitting antenna 12', and the first transmitting antenna 13', which are arranged on the front surface of the substrate 10'.

[0029] As shown in FIG. 24, the receiving antenna 20' includes receiving antennas 20A', 20B', 20C', and 20D'. As shown in FIG. 24, the receiving antennas 20A', 20B', 20C', and 20D' each include multiple radiating elements. Each of these radiating elements may be made of a metal material such as copper. In the example shown in FIG. 24, the receiving antennas 20A', 20B', 20C', and 20D' each include four radiating elements, two on the upper side and two on the lower side. In each of the receiving antennas 20A', 20B', 20C', and 20D', the upper two radiating elements are electrically connected in series vertically, and the lower two radiating elements are also electrically connected in series vertically.

[0030] As shown in FIG. 24, in the receiving antenna 20A', the lower ends of the two upper series-connected radiating elements and the upper ends of the two lower series-connected radiating elements are electrically connected to a feed point 40A'. The feed point 40A' feeds the multiple radiating elements that make up the receiving antenna 20A'. In the receiving antenna 20B', the lower ends of the two upper series-connected radiating elements and the upper ends of the two lower series-connected radiating elements are electrically connected to a feed point 40B'. The feed point 40B' feeds the multiple radiating elements that make up the receiving antenna 20B'. In the receiving antenna 20C', the lower ends of the upper two series-connected radiating elements and the upper ends of the two lower series-connected radiating elements are electrically connected to a feed point 40C'. The feed point 40C' feeds the multiple radiating elements that make up the receiving antenna 20C'. In the receiving antenna 20D', the lower ends of the two upper series-connected radiating elements and the upper ends of the two lower series-connected radiating elements are each electrically connected to a feed point 40D'. The feed point 40D' feeds the multiple radiating elements that make up the receiving antenna 20D'. In each of the receiving antennas 20A', 20B', 20C', and 20D', the upper two series-connected radiating elements and the lower two series-connected radiating elements may be arranged on approximately the same line, as shown in FIG. 24. In this way, the receiving antennas 20A', 20B', 20C', and 20D' may form an array antenna.

[0031] Feed point 40A', feed point 40B', feed point 40C', and feed point 40D' each supply power from the back surface of substrate 10' shown in FIG. 25 to the front surface of substrate 10' shown in FIG. 24. For this reason, feed point 40A', feed point 40B', feed point 40C', and feed point 40D' may each be configured to include a conductor that penetrates substrate 10' in the thickness direction. Feed point 40A', feed point 40B', feed point 40C', and feed point 40D' each supply power from the back surface of substrate 10' to receiving antenna 20A', receiving antenna 20B', receiving antenna 20C', and receiving antenna 20D', which are arranged on the front surface of substrate 10'.

[0032] In each of the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13', the wiring connecting the seven upper radiating elements (wiring connecting adjacent radiating elements in series) may be the same length. In each of the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13', the wiring connecting the seven lower radiating elements may also be the same length. For example, the length of each of these wirings (wiring connecting adjacent radiating elements) may be the same as the wavelength λ of the transmission wave transmitted from the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13'. By making the length of the wiring connecting adjacent radiating elements the same as the wavelength λ of the transmission wave, the phases of the transmission waves transmitted from the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' can be aligned. Of course, the length of the wiring may be the length of the wavelength λ, but in the case of a transmission line, it is multiplied by the wavelength shortening rate 1 / √εr = (εr)^(-0.5), which is determined by the relative permittivity of the dielectric material that makes up the substrate. In other words, the wavelength of the transmitted wave on the transmission line may be shorter than the wavelength λ0 in a vacuum. In this disclosure, the wavelength of an electromagnetic wave in a vacuum is λ0, and the wavelength in a medium with a relative permittivity εr is λ. Then, it is assumed that λ = λ0(εr)^(-0.5) holds.

[0033] Furthermore, in each of the receiving antennas 20A', 20B', 20C', and 20D', the wiring connecting the two upper radiating elements (wiring connecting adjacent radiating elements in series) may be the same length. In each of the receiving antennas 20A', 20B', 20C', and 20D', the wiring connecting the two lower radiating elements (wiring connecting adjacent radiating elements in series) may be the same length. Such wiring (wiring connecting adjacent radiating elements) may have a length equal to, for example, the wavelength λ of the transmitted wave. By setting the length of the wiring connecting adjacent radiating elements to the same length as the wavelength λ of the transmitted wave, the phases of the reflected waves received from the receiving antennas 20A', 20B', 20C', and 20D' can be aligned. Although the length of the wiring can be considered to be the length of the wavelength λ0, in the case of a transmission line, it is multiplied by the wavelength shortening rate (εr)^(-0.5), which is determined by the relative permittivity of the dielectric material that makes up the substrate. In other words, the wavelength of the received wave on the transmission line can be considered to be shorter than the wavelength λ0 in a vacuum.

[0034] The wiring connecting feed point 31', feed point 32', and feed point 33' to the radiating elements arranged above and below them may have a length equal to, for example, the wavelength λ of the transmission wave. With this configuration, the phases of the transmission waves transmitted from first transmitting antenna 11', second transmitting antenna 12', and third transmitting antenna 13' can be aligned. Furthermore, the wiring connecting feed point 40A', feed point 40B', feed point 40C', and feed point 40D' to the radiating elements arranged above and below them may have a length equal to, for example, the wavelength λ of the transmission wave.

[0035] 25, electronic device 100 includes control unit 50′ on the back surface of substrate 10′. Electronic device 100 also includes feed point 31′, feed point 32′, feed point 33′, feed point 40A′, feed point 40B′, feed point 40C′, and feed point 40D′ on the back surface of substrate 10′.

[0036] The control unit 50' can control the overall operation of the electronic device 100, including the control of each functional unit constituting the electronic device 100. The control unit 50' 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 control unit 50' 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 one embodiment, the control unit 50' may be configured as, for example, a CPU and a program executed by the CPU. The control unit 50' may also be configured as an arbitrary SoC (system-on-a-chip) or the like. The control unit 50' may include an arbitrary memory, as appropriate. In one embodiment, the optional memory may store various parameters for defining the transmission waves transmitted from at least one of the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13'.

[0037] Feed points 40A' to 40D' and feed points 31' to 33' shown in Fig. 25 correspond to feed points 40A' to 40D' and feed points 31' to 33' shown in Fig. 24, respectively. Feed points 40A' to 40D' and feed points 31' to 33' shown in Fig. 25 are electrically connected to feed points 40A' to 40D' and feed points 31' to 33' shown in Fig. 24, respectively. These corresponding feed points may be electrically connected to each other by, for example, conductors, for example, via through holes drilled in the substrate 10'.

[0038] As shown in FIG. 25 , feed point 31′ may be electrically connected to transmit port 61′ by wiring. Feed point 32′ may be electrically connected to transmit port 62′ by wiring. Feed point 33′ may be electrically connected to transmit port 63′ by wiring. Transmit port 61′, transmit port 62′, and transmit port 63′ may each be a transmit RF (Radio Frequency) port of control unit 50′. The wires connecting feed point 31′ and transmit port 61′, the wires connecting feed point 32′ and transmit port 62′, and the wires connecting feed point 33′ and transmit port 63′ may be the same length. With this configuration, if transmit waves of the same phase are simultaneously output from transmit port 61′, transmit port 62′, and transmit port 63′ of control unit 50′, the phases of the transmit signals supplied to feed point 31′, feed point 32′, and feed point 33′ can be aligned.

[0039] 25, feed point 40A' may be electrically connected to receive port 70A' by wiring. Feed point 40B' may be electrically connected to receive port 70B' by wiring. Feed point 40C' may be electrically connected to receive port 70C' by wiring. Feed point 40D' may be electrically connected to receive port 70D' by wiring. Receive port 70A', receive port 70B', receive port 70C', and receive port 70D' may each be a receive RF port of controller 50'. The wire connecting feed point 40A' and receive port 70A', the wire connecting feed point 40B' and receive port 70B', the wire connecting feed point 40C' and receive port 70C', and the wire connecting feed point 40D' and transmit port 70D' may be the same length. With this configuration, the phases of the received signals supplied simultaneously with the same phase from the feed points 40A' to 40D' to the receiving ports 70A' to 70D' of the control unit 50' can be aligned.

[0040] As described above, making the wiring connecting adjacent radiating elements and the wiring connecting radiating elements and feed points all the same length may be a design when transmitting transmission waves simultaneously (at the same timing). For example, when transmitting transmission waves not simultaneously (at the same timing), the wiring connecting adjacent radiating elements and / or the wiring connecting radiating elements and feed points do not need to be the same length.

[0041] The first transmitting antenna 11', second transmitting antenna 12', and third transmitting antenna 13' of the electronic device 100 may transmit 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 first transmitting antenna 11', second transmitting antenna 12', and third transmitting antenna 13' of the electronic device 100 may transmit radio waves having a frequency bandwidth of 4 GHz, such as 77 GHz to 81 GHz. In the electronic device 100, a transmission signal for transmitting such transmission waves may be generated by, for example, the control unit 50'.

[0042] 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.

[0043] With the above-described configuration, the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' of the electronic device 100 can transmit electromagnetic waves (transmitting waves) for detecting an object. Also, the receiving antennas 20A', 20B', 20C', and 20D' of the electronic device 100 can receive reflected waves of the transmitting waves reflected by an object.

[0044] Here, we consider a case where a transmission wave is transmitted from only one of the first transmitting antenna 11′, the second transmitting antenna 12′, and the third transmitting antenna 13′. For example, we will explain a case where the control unit 50′ controls the transmission wave to be transmitted only from the first transmitting antenna 11′. As described above, the power supply path from each of the multiple radiating elements constituting the first transmitting antenna 11′ to the power supply point 31′ is an integer multiple of the wavelength λ of the transmission wave. Therefore, as described above, the transmission waves transmitted from the multiple radiating elements constituting the first transmitting antenna 11′ are in phase with each other. Therefore, the first transmitting antenna 11′ as a whole has directivity in the positive direction of the Z axis shown in FIG. 24, i.e., the front direction of the electronic device 100 (board 10′), and forms a beam of the transmission wave. FIG. 26 is a diagram explaining the directivity of the antenna of the electronic device 100. As shown in FIG. 26, the first transmitting antenna 11′ as a whole has directivity in the positive direction of the Z axis shown in FIG. 26, i.e., direction d1, and forms a beam of the transmission wave as shown in FIG. 26.

[0045] The same applies when, for example, the control unit 50' controls the transmission of a transmission wave from only one of the second transmitting antenna 12' or the third transmitting antenna 13'. Therefore, the second transmitting antenna 12' or the third transmitting antenna 13' as a whole has directivity in the positive direction of the Z axis shown in FIG. 24, i.e., in the front direction of the electronic device 100 (board 10'), and forms a beam of the transmission wave. As shown in FIG. 26, the second transmitting antenna 12' or the third transmitting antenna 13' as a whole has directivity in the positive direction of the Z axis shown in FIG. 26, i.e., in direction d1, and forms a beam of the transmission wave as shown in FIG.

[0046] Next, consider the case where transmission waves are transmitted from all of the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13'. As described above, the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' are connected in phase with each other. Therefore, the transmission waves transmitted from the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' are combined in phase with each other. Furthermore, all of the first transmitting antenna 11' to the third transmitting antenna 13' have directivity in the positive direction of the Z axis, i.e., the frontward direction. Therefore, the combined transmission waves transmitted from all of the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' (composite wave) have directivity in the positive direction of the Z axis, i.e., the frontward direction, and form a beam of the composite wave in the positive direction of the Z axis, i.e., the frontward direction (see FIG. 26).

[0047] As described above, the composite wave transmitted from the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' has its main lobe directed in the positive direction of the Z axis, i.e., in the front direction (0° in both the X-axis and Y-axis directions) relative to the surface of the substrate 10'. Furthermore, the composite wave transmitted from the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' has a greater gain than a transmission wave transmitted from only one of these antennas. Therefore, the composite wave transmitted from the first transmitting antenna 11', the second transmitting antenna 12', and the third transmitting antenna 13' can extend the detection distance more than a transmission wave transmitted from only one of these antennas. Meanwhile, the directivity of the transmission wave transmitted from the first transmitting antenna 11', the second transmitting antenna 12', and / or the third transmitting antenna 13' in the front direction (0° in both the X-axis and Y-axis directions) becomes sharper (narrower) as the number of radiating elements increases, as described below. For this reason, the directivity of the transmission waves transmitted from each of the 14 radiating elements, such as the first transmitting antenna 11', the second transmitting antenna 12', or the third transmitting antenna 13', becomes relatively sharp (narrow). Here, the directivity of the transmitting antenna has been explained, but the directivity of the receiving antenna also has similar characteristics to the directivity of the transmitting antenna.

[0048] To detect objects at relatively long distances using technologies such as millimeter-wave radar, a high-gain antenna is required. In such cases, multiple antenna elements are arranged according to the required gain, and by combining them in phase, the directivity can be directed in the desired direction. In this case, the higher the gain of the antenna, the more elements are required, and the narrower the directivity becomes.

[0049] The electronic device 100 described above is useful in certain use cases. However, there are also expected use cases in which functions that are difficult to achieve with the electronic device 100 are desired. For example, as in the above-mentioned radar device installed at or near a roadside unit or traffic light to detect automobiles traveling on a road, functions that can be switched appropriately depending on several use cases may be desired. For example, a use case is also expected in which a device installed at a relatively high position, such as a roadside unit or traffic light or near a roadside unit or traffic light, detects automobiles and pedestrians traveling on a road. In such use cases, a function to detect automobiles and pedestrians traveling relatively close below the device may be desired. Furthermore, in the above-mentioned use cases, it may be desired to detect automobiles and pedestrians located relatively far from the device.

[0050] Even if we try to meet such demands, the electronic device 100 cannot change the direction of its directivity. Therefore, the electronic device 100 cannot change its directivity from a horizontal direction relatively far away from the electronic device 100 to a downward direction relatively close to the electronic device 100. It is possible for the control unit 50′ to change the directivity of the transmitted waves by controlling the phase of the transmitted waves transmitted from each radiating element (beamforming). However, even with such beamforming, the directivity of the transmitted waves transmitted from a relatively large number of radiating elements, such as the first transmitting antenna 11′, the second transmitting antenna 12′, or the third transmitting antenna 13′, becomes relatively sharp (narrow). It is also possible that the desired detection accuracy cannot be achieved even with the beamformed transmitted waves from the first transmitting antenna 11′, the second transmitting antenna 12′, or the third transmitting antenna 13′ due to the presence of null points. As described above, a millimeter-wave radar installed at a relatively high location, such as a roadside unit or a traffic light, requires high antenna gain in the downward direction to detect objects at close range. However, the directivity of the antennas combined in phase is relatively narrow, and it is expected that the gain for detecting an object may be insufficient. The electronic device 100 shown in FIG. 24 has radiating elements arranged only in the vertical direction. Therefore, in the electronic device 100, the horizontal directivity per antenna is relatively wide (half-width 40 to 50°). Therefore, according to the electronic device 100 shown in FIG. 24, even if beamforming is performed using three antennas, a reasonable steering angle can be obtained. On the other hand, the electronic device 1 shown in FIG. 1, which will be described later, has radiating elements arranged also in the horizontal direction. Therefore, even if beamforming is performed in the electronic device 1 shown in FIG. 1, the steering angle is relatively narrow.

[0051] Therefore, an electronic device according to an embodiment can switch the beam direction of a transmitted wave or a received wave, as well as the width or narrowness of the directivity, thereby improving convenience in specific usage situations. Such an electronic device will be described in further detail below.

[0052] 1 and 2 are diagrams showing the configuration of an electronic device according to an embodiment. Fig. 1 is a diagram showing the electronic device according to an embodiment as viewed from a predetermined direction. The predetermined direction in Fig. 1 may be the same as the predetermined direction mentioned in Fig. 24. Fig. 2 is a diagram showing the electronic device according to an embodiment as viewed from a direction opposite to the predetermined direction in Fig. 1.

[0053] 1 and 2, the X-axis direction may be the horizontal direction or the left-right direction. In FIG. 1 and 2, the Y-axis direction may be the vertical direction or the up-down direction. In particular, in FIG. 1 and 2, the positive Y-axis direction may be the upward direction, and the negative Y-axis direction may be the downward direction. In FIG. 1 and 2, the Z-axis direction may be the front-to-back direction. In particular, in FIG. 1 and 2, the positive Z-axis direction may be the forward direction or the front (front) direction, and the negative Z-axis direction may be the backward direction or the rear direction.

[0054] As shown in Figures 1 and 2, an electronic device 1 according to an embodiment may include a substrate 10. The substrate 10 may be a circuit board used in ordinary electric or electronic circuits. The surface of the substrate 10 shown in Figure 1 (i.e., the surface of the substrate 10 facing in the positive direction of the Z axis) will also be referred to as the front surface or surface for convenience. Furthermore, the surface of the substrate 10 shown in Figure 2 (i.e., the surface of the substrate 10 facing in the negative direction of the Z axis) will also be referred to as the back surface or rear surface for convenience. Figures 1 and 2 show functional parts of the transmission system and reception system of the electronic device 1.

[0055] 1, the electronic device 1 includes a first transmitting antenna 11, a second transmitting antenna 12, and a third transmitting antenna 13 on the surface of the substrate 10. As shown in Fig. 1, the electronic device 1 includes a first receiving antenna 21 and a second receiving antenna 22 on the surface of the substrate 10. The first transmitting antenna 11, the second transmitting antenna 12, the third transmitting antenna 13, the first receiving antenna 21, and the second receiving antenna 22 may be planar antennas (patch antennas) that are commonly used in millimeter-wave radar.

[0056] 1, the first transmitting antenna 11 may be configured as a transmitting patch antenna on the right side of the electronic device 1 in Fig. 1, and the second transmitting antenna 12 may be configured as a transmitting patch antenna on the left side of the electronic device 1 in Fig. 1. As shown in Fig. 1, the first transmitting antenna 11 and the second transmitting antenna 12 may be arranged adjacent to each other on the left and right sides above the center of the substrate 10. The third transmitting antenna 12 may be arranged on the lower side of the substrate 10, closer to the first transmitting antenna 11 than the center of the first transmitting antenna 11 and the second transmitting antenna 12 in the left and right direction.

[0057] As shown in Fig. 1, the first transmitting antenna 11 may include transmitting antenna 11A, transmitting antenna 11B, transmitting antenna 11C, and transmitting antenna 11D. The second transmitting antenna 12 may include transmitting antenna 12A, transmitting antenna 12B, transmitting antenna 12C, and transmitting antenna 12D. The third transmitting antenna 13 may include transmitting antenna 13A. As shown in Fig. 1, the first transmitting antenna 11, the second transmitting antenna 12, and the third transmitting antenna 13 may each include a plurality of radiating elements. Each of these radiating elements may be made of a metal material such as copper.

[0058] In the example shown in FIG. 1, the first transmitting antennas 11A to 11D and the second transmitting antennas 12A to 12D each include eight radiating elements, four on the upper side and four on the lower side. As shown in FIG. 1, the radiating elements constituting the first transmitting antennas 11A to 11D and the second transmitting antennas 12A to 12D may be fed horizontally. In each of the first transmitting antennas 11A to 11D and the second transmitting antennas 12A to 12D, the four radiating elements on the upper side are arranged vertically and electrically connected to be fed horizontally. In addition, the four radiating elements on the lower side of the first transmitting antennas 11A to 11D and the second transmitting antennas 12A to 12D are also arranged vertically and electrically connected to be fed horizontally.

[0059] The third transmitting antenna 13 also includes four radiating elements. As shown in Fig. 1, each of the radiating elements constituting the third transmitting antenna 13 may be fed vertically. In the third transmitting antenna 13, the four radiating elements are arranged vertically and electrically connected in series so as to be fed vertically.

[0060] As shown in FIG. 1, in the first transmitting antennas 11A to 11D, the lower ends of the four connected radiating elements on the upper side and the upper ends of the four connected radiating elements on the lower side are electrically connected to feed points 31A to 31D, respectively. The feed points 31A to 31D feed power to the multiple radiating elements constituting the first transmitting antennas 11A to 11D, respectively. In the second transmitting antennas 12A to 12D, the lower ends of the four connected radiating elements on the upper side and the upper ends of the four connected radiating elements on the lower side are electrically connected to feed points 32A to 32D, respectively. The feed points 32A to 32D feed power to the multiple radiating elements constituting the second transmitting antennas 12A to 12D, respectively. In the third transmitting antenna 13 (third transmitting antenna 13A), the upper ends of the four series-connected radiating elements are electrically connected to feed point 33. The feeding point 33 feeds power to a plurality of radiating elements that form the third transmitting antenna 13 (third transmitting antenna 13A).

[0061] In the first transmitting antenna 11 and the second transmitting antenna 12, the four connected radiating elements on the top side and the four connected radiating elements on the bottom side may be arranged vertically and fed horizontally as shown in Fig. 1. In addition, in the third transmitting antenna 13, the four series-connected radiating elements may be arranged vertically and fed vertically as shown in Fig. 1. In this way, the first transmitting antenna 11, the second transmitting antenna 12, and the third transmitting antenna 13 may form an array antenna.

[0062] The feed points 31A to 31D, the feed points 32A to 32D, and the feed point 33 each supply power from the back surface of the substrate 10 shown in FIG. 2 to the front surface of the substrate 10 shown in FIG. 1. For this reason, the feed points 31A to 31D, the feed points 32A to 32D, and the feed point 33 may each include a conductor that penetrates the substrate 10 in the thickness direction. The feed points 31A to 31D each supply power from the back side of the substrate 10 to the first transmitting antennas 11A to 11D arranged on the front surface of the substrate 10. The feed points 32A to 32D each supply power from the back side of the substrate 10 to the second transmitting antennas 12A to 12D arranged on the front surface of the substrate 10. The feeding point 33 feeds power from the rear surface side of the substrate 10 to the third transmitting antenna 13 (third transmitting antenna 13A) arranged on the front surface of the substrate 10.

[0063] 1, the receiving antenna of the electronic device 1 may include receiving antenna 20A, receiving antenna 20B, receiving antenna 20C, and receiving antenna 20D on the surface of the substrate 10. As shown in Fig. 1, each of the receiving antennas 20A to 20D may include multiple radiating elements. Each of these radiating elements may be made of a metal material such as copper.

[0064] In the example shown in FIG. 1, each of the receiving antennas 20A to 20D includes eight radiating elements, four on the upper side and four on the lower side. As shown in FIG. 1, the upper four radiating elements constituting each of the receiving antennas 20A to 20D may be fed horizontally. The upper four radiating elements of each of the receiving antennas 20A to 20D may be arranged vertically and electrically connected to be fed horizontally. Meanwhile, the lower four radiating elements constituting each of the receiving antennas 20A to 20D may be fed vertically. The lower four radiating elements of each of the receiving antennas 20A to 20D may be arranged vertically and electrically connected to be fed vertically. As a result, the electronic device 1 of this embodiment can transmit and / or receive horizontally polarized waves and vertically polarized waves. Furthermore, by arranging the electronic device 1 of this embodiment as shown in Fig. 1, interference between antenna elements is suppressed, particularly interference between horizontally polarized waves and vertically polarized waves, and desired characteristics as designed, such as suppressing gain reduction, can be obtained. In the structure of the electronic device 1 of this embodiment, it is important that the antenna elements are linearly arranged above and below the power feed branch. As will be clear from the explanation of directivity shown in Fig. 3 below, the electronic device 1 of this embodiment is an example that transmits beams directed forward and downward. In the electronic device 1 of this embodiment, the small overlap of optical paths may be one reason why desired characteristics as designed, such as suppressing gain reduction, can be obtained.

[0065] In the electronic device 1 of this embodiment, the radiating elements constituting the transmitting antenna 11 and the transmitting antenna 12 may be fed in a first direction, and the radiating elements constituting the transmitting antenna 13 may be fed in a second direction different from the first direction. Here, the first and second directions may be perpendicular to each other or may form an angle other than perpendicular. Furthermore, the first and second directions may be parallel to the X-axis or Y-axis shown in FIG. 1 , or may not be parallel. In the electronic device of this embodiment, the radiating elements constituting the receiving antenna 21 may be fed in a third direction, and the radiating elements constituting the receiving antenna 22 may be fed in a fourth direction different from the third direction. Here, the third and fourth directions may be perpendicular to each other or may form an angle other than perpendicular. Furthermore, the third and fourth directions may be parallel to the X-axis or Y-axis shown in FIG. 1 , or may not be parallel. In the present disclosure, the direction in which the radiating elements are fed may be the direction in which the power supply wiring connected to the radiating elements is connected.

[0066] 1, in receiving antennas 20A to 20D, the lower ends of the four connected radiating elements on the upper side and the upper ends of the four connected radiating elements on the lower side are electrically connected to feed points 40A to 40D, respectively. Feed points 40A to 40D feed power to the multiple radiating elements that make up receiving antennas 20A to 20D, respectively.

[0067] In the receiving antennas 20A to 20D, the four connected radiating elements at the top may be arranged vertically and fed horizontally, as shown in FIG. 1. As shown in FIG. 1, in the receiving antennas 20A to 20D, the four connected radiating elements at the top may function as the first receiving antenna 21. In the receiving antennas 20A to 20D, the four connected radiating elements at the bottom may be arranged vertically and fed vertically, as shown in FIG. 1. As shown in FIG. 1, in the receiving antennas 20A to 20D, the four connected radiating elements at the bottom may function as the second receiving antenna 22. In this way, the receiving antennas 20A to 20D, or the first receiving antenna 21 and the second receiving antenna 22, may form an array antenna.

[0068] The feed points 40A to 40D each supply power to the front surface of the substrate 10 shown in FIG. 1 from the back surface of the substrate 10 shown in FIG. 2. For this reason, the feed points 40A to 40D may each be configured to include a conductor that penetrates the substrate 10 in the thickness direction. The feed points 40A, 40B, 40C, and 40D each supply power to the receiving antennas 20A, 20B, 20C, and 20D, which are arranged on the front surface of the substrate 10, from the back surface of the substrate 10. In the present disclosure, the first receiving antenna 21 and the second receiving antenna 22 are capable of simultaneous reception in a horizontal directivity direction (d1 in FIG. 3) and a downward directivity direction (d2 in FIG. 3) without a mechanism such as a selector switch.

[0069] In the first transmitting antenna 11 and the second transmitting antenna 12, the wiring connecting the four upper radiating elements (wiring connecting adjacent radiating elements in series) may be the same length. In the first transmitting antenna 11 and the second transmitting antenna 12, the wiring connecting the four lower radiating elements may also be the same length. In the third transmitting antenna 13, the wiring connecting the four radiating elements may also be longer than and the same length as the wiring connecting the four upper radiating elements of the first transmitting antenna 11 and the second transmitting antenna 12. In this way, in the first transmitting antenna 11 and the second transmitting antenna 12, the wiring (wiring connecting adjacent radiating elements) may have a length equal to, for example, the wavelength λ of the transmission wave transmitted from the first transmitting antenna 11 and the second transmitting antenna 12.

[0070] In the third transmitting antenna 13, each wiring (wiring connecting adjacent radiating elements) may be longer than the wavelength λ of the transmission wave transmitted from the third transmitting antenna 13. By making the length of the wiring connecting adjacent radiating elements the same as the wavelength λ of the transmission wave, the phases of the transmission waves transmitted from the first transmitting antenna 11 and the second transmitting antenna 12 can be aligned. Furthermore, by making each wiring (wiring connecting adjacent radiating elements) in the third transmitting antenna 13 longer than the wavelength λ of the transmission wave transmitted from the third transmitting antenna 13, the directivity of the third transmitting antenna 13 can be made downward. In the first transmitting antenna 11 and the second transmitting antenna 12, each wiring (wiring connecting adjacent radiating elements in series) connecting the upper four radiating elements does not have to be the same length as, for example, the wavelength λ of the transmission wave transmitted from the first transmitting antenna 11 and the second transmitting antenna 12.

[0071] In the first transmitting antenna 11, the second transmitting antenna 12, and the third transmitting antenna 13, the length of each wiring connecting the radiating elements is the wavelength λ, including the wavelength shortening factor. In other words, in the present disclosure, the wiring length may be the length of the wavelength λ. Furthermore, in the case of a transmission line, in the present disclosure, the wavelength of a signal on the transmission line may be multiplied by the wavelength shortening factor (εr)^(-0.5), which is determined by the relative permittivity of the dielectric material constituting the substrate. In other words, in the present disclosure, the wavelength of a signal on the transmission line may be shorter than the wavelength λ0 in a vacuum. In this way, the electronic device 1 of the present disclosure can adjust the directionality of the transmitted radio waves by adjusting the length of each wiring connecting the radiating elements in the first transmitting antenna 11, the second transmitting antenna 12, and the third transmitting antenna 13.

[0072] Furthermore, in each of the receiving antennas 20A, 20B, 20C, and 20D, the wiring connecting the four upper radiating elements (wiring connecting adjacent radiating elements in series) may be the same length. In each of the receiving antennas 20A, 20B, 20C, and 20D, the wiring connecting the four lower radiating elements (wiring connecting adjacent radiating elements in series) may be the same length. Furthermore, in the present disclosure, the wiring connecting the four upper radiating elements (wiring connecting adjacent radiating elements) may have a length equal to, for example, the wavelength λ of the transmitted wave. In this case, the wiring connecting the four lower radiating elements may be longer than, for example, the wavelength λ of the transmitted wave. By making the lengths of the wiring connecting adjacent radiating elements the same, the phases of the reflected waves received from the receiving antennas 20A, 20B, 20C, and 20D can be aligned. Furthermore, with this arrangement, the phases of the reflected waves received by the first receiving antenna 21 and the second receiving antenna 22 can be aligned.

[0073] Furthermore, in the present disclosure, each of these wirings (wirings connecting adjacent radiating elements) may have a length equal to, for example, the wavelength λ of the transmitted wave. By making the length of the wirings connecting adjacent radiating elements equal to the wavelength λ of the transmitted wave, it is possible to align the phases of the reflected waves received from the receiving antenna 20A, receiving antenna 20B, receiving antenna 20C, and receiving antenna 20D. Furthermore, with this arrangement, it is possible to align the phases of the reflected waves received from the first receiving antenna 21 and the second receiving antenna 22.

[0074] Furthermore, in the present disclosure, in the case of a transmission line, the wavelength of a signal on the transmission line may be multiplied by a wavelength shortening rate (εr)^(-0.5), which is determined by the relative permittivity of the dielectric material constituting the substrate. In other words, in the present disclosure, the wavelength of a signal on the transmission line may be shorter than the wavelength λ0 in a vacuum. As described above, in the electronic device 1 of the present disclosure, the directivity of the received radio waves can be adjusted by adjusting the length of the wiring connecting the radiating elements in the first receiving antenna 21 and the second receiving antenna 22. Furthermore, the electronic device 1 (receiving device) according to one embodiment may include a first receiving antenna 21 and a second receiving antenna 22. The first receiving antenna 21 has directivity in a first direction d1. The second receiving antenna 22 has directivity in a second direction d2. Here, the second direction d2 may be a direction different from the first direction d1. In the present disclosure, the first direction d1 may be horizontal (horizontal to the z-axis), and the second direction d2 may be downward (at a predetermined angle θ with respect to the z-axis). In the present disclosure, the second direction d2 may be horizontal (horizontal to the z-axis) and the first direction d1 may be downward (at a predetermined angle θ with respect to the z-axis). The first receiving antenna 21 may be configured to maximize its receiving gain when the radio waves received by the first receiving antenna 21 are polarized in a first polarization direction (horizontal polarization). The second receiving antenna 22 may be configured to maximize its receiving gain when the radio waves received by the second receiving antenna 22 are polarized in a second polarization direction (vertical polarization). The second polarization direction may be a direction different from the first polarization direction. In the present disclosure, the first receiving antenna 21 may be configured to increase its receiving gain as the polarization direction of the radio waves received by the first receiving antenna 21 approaches the first polarization direction. The second receiving antenna 22 may be configured to increase its receiving gain as the polarization direction of the radio waves received by the second receiving antenna 22 approaches a second polarization direction different from the first polarization direction. The second polarization direction may be different from the first polarization direction, and the first polarization direction and the second polarization direction may or may not be perpendicular to each other.

[0075] The wiring connecting the feed points 31A to 31D and the feed points 32A to 32D to the radiating elements arranged above and below them may each have a length equal to, for example, the wavelength λ of the transmission wave. Furthermore, the wiring connecting the feed point 33 to the radiating element arranged below it may have a length longer than, for example, the wavelength λ of the transmission wave. With this configuration, the phases of the transmission waves transmitted from the first transmitting antenna 11 and the second transmitting antenna 12 can be aligned, and the directivity of the transmission wave transmitted from the third transmitting antenna 13 can be set to, for example, downward (negative direction of the Y-axis). Furthermore, the wiring connecting the feed points 40A to 40D to the radiating elements arranged above them may have a length equal to, for example, the wavelength λ of the transmission wave. In this case, the wiring connecting the feed points 40A to 40D to the radiating elements arranged below them may have a length longer than, for example, the wavelength λ of the transmission wave.

[0076] In the electronic device 1 of the present disclosure, the wiring connecting the feed points 40A through 40D to the radiating elements disposed below them may be longer than, for example, the wavelength λ of the transmitted wave. In this case, the wiring connecting the feed points 40A through 40D to the radiating elements disposed below them may be the same length as, for example, the wavelength λ of the transmitted wave. In this way, by making the wiring connecting the radiating elements the same length as the wavelength λ of the transmitted wave, directivity may be imparted in a direction parallel to the Z axis. Furthermore, by making the wiring connecting the radiating elements different in length from the wavelength λ of the transmitted wave, directivity may be imparted in a direction not parallel to the Z axis. In the present disclosure, instead of making the wiring connecting the radiating elements longer than the wavelength λ of the transmitted wave or the received wave, the wiring connecting the radiating elements may be shorter than the wavelength λ of the transmitted wave or the received wave. In an antenna such as the first receiving antenna 21 disposed above the feed point, increasing the element spacing will result in upward directivity. When the element spacing of an antenna such as the first receiving antenna 21 located above the feed point is shortened, the directivity becomes downward. When the element spacing of an antenna such as the third transmitting antenna 13 and / or the second receiving antenna 22 located below the feed point is lengthened, the directivity becomes downward. When the element spacing of an antenna such as the third transmitting antenna 13 and / or the second receiving antenna 22 located below the feed point is shortened, the directivity becomes upward.

[0077] 2, the electronic device 1 includes a control unit 50 on the back surface of the substrate 10. The electronic device 1 also includes, on the back surface of the substrate 10, feed points 31A to 31D, feed points 32A to 32D, feed point 33, and feed points 40A to 40D.

[0078] The control unit 50 can control the overall operation of the electronic device 1, including the control of each functional unit constituting the electronic device 1. The control unit 50 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 control unit 50 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 one embodiment, the control unit 50 may be configured as, for example, a CPU and a program executed by the CPU. The control unit 50 may also be configured as an arbitrary SoC (System-on-a-Chip) or the like. The control unit 50 may include an arbitrary memory, as appropriate. In one embodiment, the optional memory may store various parameters for defining the transmission waves transmitted from at least one of the first transmitting antenna 11, the second transmitting antenna 12, and the third transmitting antenna 13.

[0079] Feed points 31A to 31D, feed points 32A to 32D, and feed point 33 shown in Fig. 2 correspond to feed points 31A to 31D, feed points 32A to 32D, and feed point 33 shown in Fig. 1, respectively. Feed points 40A to 40D shown in Fig. 2 correspond to feed points 40A to 40D shown in Fig. 1, respectively. These corresponding feed points may be electrically connected to each other by, for example, a conductor, for example, via a through hole drilled in the substrate 10.

[0080] As shown in FIG. 2, feed points 31A to 31D may be electrically connected to transmit port 61 by wiring. Feed points 32A to 32D may be electrically connected to transmit port 62 by wiring. Feed point 33 may be electrically connected to transmit port 63 by wiring. Transmit port 61, transmit port 62, and transmit port 63 may each be a transmit RF (Radio Frequency) port of control unit 50. The wires connecting feed points 31A to 31D to transmit port 61 and the wires connecting feed points 32A to 32D to transmit port 62 may be the same length. With this configuration, if transmit waves of the same phase are output simultaneously from transmit port 61 and transmit port 62 of control unit 50, the phases of the transmit signals supplied to feed points 31 and 32 can be aligned.

[0081] 2, feed points 40A to 40D may be electrically connected to receive ports 70A to 70D by wiring, respectively. Receive ports 70A to 70D may be receive RF ports of controller 50, respectively. The wiring connecting feed points 40A to 40D and receive ports 70A to 70D may be the same length. This configuration allows the phases of received signals supplied simultaneously and in the same phase from feed points 40A to 40D to receive ports 70A to 70D of controller 50 to be aligned.

[0082] As described above, making the wiring connecting adjacent radiating elements and the wiring connecting radiating elements and feed points all the same length may be a design when transmitting transmission waves simultaneously (at the same timing). For example, when transmitting transmission waves not simultaneously (at the same timing), the wiring connecting adjacent radiating elements and / or the wiring connecting radiating elements and feed points do not need to be the same length.

[0083] The first transmitting antenna 11, the second transmitting antenna 12, and the third transmitting antenna 13 of the electronic device 1 may transmit 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 first transmitting antenna 11, the second transmitting antenna 12, and the third transmitting antenna 13 of the electronic device 1 may transmit radio waves having a frequency bandwidth of 4 GHz, such as 77 GHz to 81 GHz. In the electronic device 1, a transmission signal for transmitting such transmission waves may be generated by, for example, the control unit 50.

[0084] With the above-described configuration, the first transmitting antenna 11, the second transmitting antenna 12, and the third transmitting antenna 13 of the electronic device 1 can transmit electromagnetic waves (transmitting waves) for detecting an object. Also, the first receiving antenna 21 and the second receiving antenna 22 of the electronic device 1 can receive reflected waves of the transmitting waves reflected by an object.

[0085] As shown in FIG. 2, in the electronic device 1, a control unit 50 is mounted on the back surface of the substrate 10. The two transmitting ports 61 and 62 of the control unit 50 are wired with equal lengths to the feed points 31A to 31D and the feed points 32A to 32D, respectively. Therefore, the first transmitting antenna 11 and the second transmitting antenna 12 are connected to the control unit 50 by paths of equal length. As shown in FIG. 2, the wiring connected to the transmitting port 61 and the transmitting port 62 is divided into four and connected to the feed points 31A to 31D and the feed points 32A to 32D on the front surface of the substrate 10. The four receiving ports 70A to 70D of the control unit 50 are wired with equal lengths to the corresponding feed points 40A to 40D, respectively. Therefore, the receiving antenna 20A, the receiving antenna 20B, the receiving antenna 20C, and the receiving antenna 20D are connected to the control unit 50 by paths of equal length.

[0086] In the electronic device 1, the number of radiating elements constituting each of the transmitting antenna and / or receiving antenna, and the number of lines distributed from the transmitting port and / or receiving port of the control unit 50 to the feed point may vary depending on the system design. For example, in the electronic device 1 according to one embodiment, the number of radiating elements constituting each of the transmitting antenna and / or receiving antenna may be 16 elements in one column instead of 8 elements in one column. Also, in the electronic device 1 according to one embodiment, the line connecting one transmitting port of the control unit 50 to the feed point may be 8 lines instead of 4 lines. Furthermore, the electronic device 1 may include a branching circuit that branches signals from the feed points of the first receiving antenna 21 and the second receiving antenna 22, as appropriate.

[0087] Fig. 3 is a diagram illustrating the directivity of the electronic device 1. The electronic device 1 shown in Fig. 3 is a diagram showing the electronic device 1 shown in Fig. 1 and Fig. 2 as viewed from the side. In Fig. 3, only the substrate 10, the first receiving antenna 21, and the second receiving antenna 22 of the electronic device 1 are shown, and other functional parts are omitted from the illustration.

[0088] As shown in FIG. 1, each radiating element included in the first receiving antenna 21 is fed from the right side of the respective radiating element. Therefore, the polarization plane of the linearly polarized wave of the radiating element included in the first receiving antenna 21 is horizontal with respect to the ground (parallel to the X-axis), i.e., horizontally polarized. Furthermore, the spacing between each radiating element included in the first receiving antenna 21 is such that each input is in phase. Therefore, the directivity of each radiating element included in the first receiving antenna 21 faces the front direction (positive direction of the Z-axis) with respect to the substrate 10, as shown in direction d1 in FIG. 3. FIG. 3 shows how the directivity of the first receiving antenna 21 faces in direction d1, and how a beam is formed in this direction.

[0089] On the other hand, as shown in Fig. 1, each radiating element included in the second receiving antenna 22 is fed from the upper side of the respective radiating element. Therefore, the polarization plane of the linearly polarized wave of the radiating element included in the second receiving antenna 22 is perpendicular to the ground (perpendicular to the X-axis), i.e., vertically polarized. Furthermore, the radiating elements included in the second receiving antenna 22 are arranged at intervals that result in a phase difference such that the directivity includes a downward component (i.e., diagonally downward). Therefore, the directivity of each radiating element included in the second receiving antenna 22 faces diagonally downward with respect to the substrate 10, as shown in direction d2 in Fig. 3 (a direction including a negative Y-axis component). Fig. 3 shows how the directivity of the second receiving antenna 22 faces in direction d2, and how a beam is formed in this direction.

[0090] In the radiating elements that make up the array antenna, the directivity in the horizontal and vertical directions varies slightly depending on the power feed position of the radiating element. This is because the symmetry of the electromagnetic field is broken by the power feed. In the electronic device 1 according to one embodiment, by applying horizontally polarized waves to the first receiving antenna and vertically polarized waves to the second receiving antenna, the radar coverage area is expanded. This point will be explained with reference to FIGS. 4, 5, and 6. FIG. 4 is a top view of the antenna of the electronic device 1 according to this embodiment. FIG. 5 is a top view of a three-dimensional polar coordinate plot of the gain of the electronic device according to this embodiment. FIG. 6 is a graph showing a plot of the gain of the electronic device 1 according to this embodiment.

[0091] In FIG. 4, the X-axis direction is the vertical downward direction parallel to the antenna surface, the Y-axis direction is the horizontal direction parallel to the antenna surface, and the Z-axis direction is the direction perpendicular to the antenna surface and opposite to the direction of radio wave incidence. In FIG. 4, the X-axis direction is the E-plane (electric field plane) and is the direction indicating the gain of X-axis direction polarized waves. The Y-axis direction is the H-plane (magnetic field plane) and is the direction indicating the gain of Y-axis direction polarized waves. As shown in FIGS. 5 and 6, in the embodiment of the present disclosure, in the 3D radiation pattern viewed from the Z-axis direction, the gain value at Phi 90° in the Y-axis direction is smaller than the gain value at Phi 0° in the X-axis direction. The graph of gain of X-axis direction polarized waves in FIG. 6 corresponds to vertical polarization according to the present disclosure, and the graph of gain of Y-axis direction polarized waves corresponds to horizontal polarization. Therefore, in the present disclosure, the gain of X-axis direction polarized waves (vertical direction) has wider directivity than the gain of Y-axis direction polarized waves (horizontal direction). Therefore, in this disclosure, by utilizing the fact that the directivity in the horizontal and vertical directions differs slightly depending on the feed position in the elements of the array antenna, it is possible to adjust the directivity to widen or narrow the desired direction. Also, in Figure 5, angle θ indicates the angle with the z-axis, and angle φ indicates the angle with the x-axis in the xy plane.

[0092] As described above, in the electronic device 1 according to one embodiment, the polarization plane of the first receiving antenna 21 and the polarization plane of the second receiving antenna 22 are offset by 90° to provide orthogonality. With this configuration, the electronic device 1 according to one embodiment can reduce interference between the antennas. Furthermore, in the electronic device 1 according to one embodiment, the first receiving antenna 21 and the second receiving antenna 22 may receive radio waves (signals) of different frequencies or may receive signals of the same frequency. In the electronic device 1 according to the present disclosure, the polarization plane of the first receiving antenna 21 and the polarization plane of the second receiving antenna 22 may be offset by any angle other than 90°.

[0093] Here, each radiating element included in the first transmitting antenna 11 and the second transmitting antenna 12 is fed with power from the right side of the respective radiating element. Therefore, in the electronic device 1, the polarization planes of the radiating elements included in the first transmitting antenna 11 and the second transmitting antenna 12 and the polarization plane of the radiating element included in the first receiving antenna 21 are designed to match. Furthermore, each radiating element included in the third transmitting antenna 13 is fed with power from the upper side of the respective radiating element. Therefore, in the electronic device 1, the polarization planes of the radiating elements included in the third transmitting antenna 13 and the polarization plane of the radiating elements included in the second receiving antenna 22 are designed to match.

[0094] As described above, making the wiring connecting adjacent radiating elements and the wiring connecting radiating elements and feed points the same length in the first transmitting antenna 11 and the second transmitting antenna 12 may be a design for transmitting transmission waves simultaneously (at the same timing). For example, if the transmission waves are not transmitted simultaneously (at the same timing), the wiring connecting adjacent radiating elements and / or the wiring connecting radiating elements and feed points in the first transmitting antenna 11 and the second transmitting antenna 12 do not need to be the same length.

[0095] In the above description, it has been assumed that the polarization of each radiating element included in the first receiving antenna 21, the second transmitting antenna 12, and the third transmitting antenna 13 is linearly polarized. However, the polarization of each radiating element included in the first receiving antenna 21, the second transmitting antenna 12, and the third transmitting antenna 13 of the electronic device 1 according to an embodiment is not limited to linear polarization and may be, for example, circular polarization or elliptical polarization. Thus, the polarization in the electronic device 1 according to an embodiment may be any of linear polarization, elliptical polarization, and circular polarization. For example, in the electronic device 1 according to an embodiment, at least one of the horizontal polarization and the vertical polarization may be any of linear polarization, elliptical polarization, and circular polarization.

[0096] 1, the third transmitting antenna 13 is disposed below the first transmitting antenna 11 and the second transmitting antenna 12. This arrangement provides an advantageous effect when the electronic device 1 according to one embodiment is provided with a radome 90, which will be described later. As described above, the third transmitting antenna 13 is disposed on the underside of the substrate 10, closer to the first transmitting antenna 11 than the center between the first transmitting antenna 11 and the second transmitting antenna 12 in the left-right direction. This arrangement reduces loss in the transmission line from the control unit 50.

[0097] On the other hand, when the electronic device 1 according to the embodiment does not include a radome 90 (described later), for example, the third transmitting antenna 13 may be arranged side by side with the first transmitting antenna 11 and the second transmitting antenna 12. In this case, the transmission line of the third transmitting antenna 13 needs to be long, which increases loss. On the other hand, there is no need to arrange the third transmitting antenna 13 below the first transmitting antenna 11 and the second transmitting antenna 12. Therefore, with such an arrangement, the number of radiating elements constituting the first transmitting antenna 11 and the second transmitting antenna 12 (and the third transmitting antenna 13) can be increased.

[0098] As described above, the electronic device 1 according to one embodiment can direct the directivity of the receiving antenna, for example, in the forward direction and the diagonally downward direction, without using a functional unit such as an RF switch. Therefore, the electronic device 1 according to one embodiment can improve the convenience of object detection technology such as millimeter-wave radar.

[0099] With the above configuration, the electronic device 1 has directivity, for example, in a downward direction (diagonally downward), and can receive a wave reflected from an object when the transmitted wave is reflected therefrom. Also, with the above configuration, the electronic device 1 has directivity, for example, in a front direction (forward), and can receive a wave reflected from an object when the transmitted wave is reflected therefrom.

[0100] The electronic device 1 according to one embodiment can be used, for example, as a device installed in or near a roadside device or a traffic light to detect automobiles and pedestrians traveling on a road. That is, the electronic device 1 realizes a function to detect automobiles and the like located relatively close below the device. The electronic device 1 also realizes a function to detect automobiles and the like located relatively far away from the device in a direction close to the horizontal direction of the device.

[0101] In this way, the electronic device 1 according to one embodiment can change the direction of directivity. Therefore, the electronic device 1 according to one embodiment can switch the direction of the beam of the transmitted wave or the received wave as well as the width or narrowness of the directivity, thereby improving convenience in a specific usage mode.

[0102] Examples of the effects of the electronic device 1 according to the embodiment will be further described below.

[0103] Fig. 7 is a diagram showing an example of the effect of a configuration in which radiating elements are arranged in the vertical direction in receiving antennas 20A to 20D. Fig. 7 shows a configuration in which the number of radiating elements arranged in the vertical direction of the receiving antenna is changed from the configuration shown in Fig. 1. Below, the results of simulating the operation of such a configuration will be described.

[0104] In this simulation, a configuration with 12 radiating elements arranged vertically was adopted, as shown in Fig. 7. Of the 12 radiating elements arranged vertically, as shown in Fig. 7, the top six are horizontally polarized array antennas, and the bottom six are vertically polarized array antennas. In this simulation, the radiating elements shown in Fig. 7 were matched to 79 GHz. In this simulation, a feed point was provided for each radiating element, and the amplitude and phase of the transmitted wave could be changed individually for each.

[0105] The six radiating elements on the top side of the horizontally polarized wave shown in Fig. 7 are combined in phase, with the main lobe pointing forward (positive Z-axis direction) from the surface of the substrate 10. A phase difference is given to the six radiating elements on the bottom side of the vertically polarized wave shown in Fig. 7, with the main lobe pointing diagonally downward (having a positive Z-axis component and a negative Y-axis component) with respect to the surface of the substrate 10.

[0106] FIG. 8 is a graph plotting the gain for each polarization of the radiating element shown in FIG. 7. FIG. 8 shows the relationship between the gain of the polarization of the radiating element shown in FIG. 7 and the angle in a plane parallel to the YZ plane. The radial direction of the pie chart shown in FIG. 8 indicates the magnitude of the gain (dBi). The circumferential direction of the pie chart shown in FIG. 8 indicates the angle (°) in a plane parallel to the YZ plane. In the circumferential direction of the pie chart shown in FIG. 8, 90° indicates the positive direction of the Z axis, i.e., the front direction of the radiating element shown in FIG. 7. In the circumferential direction of the pie chart shown in FIG. 8, 0° indicates the positive direction of the Y axis, i.e., the upward direction of the radiating element shown in FIG. 7. In the circumferential direction of the pie chart shown in FIG. 8, 180° (-180°) indicates the negative direction of the Y axis, i.e., the downward direction of the radiating element shown in FIG. 7.

[0107] Of the curves shown in Fig. 8, the curve shown by the solid line indicates the gain of horizontally polarized waves by the upper six radiating elements shown in Fig. 7. The curve shown by the dashed line indicates the gain of vertically polarized waves by the lower six radiating elements shown in Fig. 7. Furthermore, the curve shown by the dashed line indicates the combined gain of horizontally polarized waves and vertically polarized waves by the upper six radiating elements and the lower six radiating elements shown in Fig. 7.

[0108] As shown in Figure 8, the main lobe of the horizontally polarized wave, indicated by the solid line, is directed forward (90°) (gain 10.7 dBi). Also, as shown in Figure 8, the main lobe of the vertically polarized wave, indicated by the dashed-dotted line, is directed downward at an angle of 45° (135°) (gain 9.8 dBi). From Figure 8, we can see that the main lobe peaks at different angles for each polarization.

[0109] Figure 9 is a diagram showing an example of a 3D plot of the gain shown in Figure 8. Figure 9 shows an example of a 3D plot of the gain curve shown by the dashed line in Figure 8, i.e., the gain obtained by combining horizontally polarized waves and vertically polarized waves from the upper six radiating elements and the lower six radiating elements shown in Figure 7. In Figure 9, the darker the grayscale color, the higher the gain. As shown in Figure 9, it can be seen that the horizontally polarized waves have a peak in the front direction, and the vertically polarized waves have a peak in the diagonally downward direction.

[0110] Next, simulation results for other configurations are shown. Figure 10 shows a configuration in which the number of radiating elements on the lower side is changed to only one in the configuration shown in Figure 7. Below, the results of simulating the operation of such a configuration are explained. In addition, in the following, explanations that overlap with the explanations of the simulations described above will be simplified or omitted as appropriate.

[0111] Fig. 11 is a diagram showing a graph plotting the gain for each polarization by the radiating elements shown in Fig. 10. Of the curves shown in Fig. 11, the curve shown by the solid line indicates the gain of horizontally polarized waves by the upper six radiating elements shown in Fig. 10. The curve shown by the dashed line indicates the gain of vertically polarized waves by the lower single radiating element shown in Fig. 10. Furthermore, the curve shown by the dashed line indicates the combined gain of horizontally polarized waves and vertically polarized waves by the upper six radiating elements and the lower single radiating element shown in Fig. 10.

[0112] As mentioned above, the configuration shown in FIG. 10 is the same as the configuration shown in FIG. 7 except that the number of lower radiating elements is reduced to only one. Therefore, as shown in FIG. 11, the curve shown by the dashed dotted line, i.e., the gain of vertical polarization, has a lower peak at a diagonal angle of 45° downward (135°) compared to the results shown in FIG. 8. On the other hand, as shown in FIG. 11, the curve shown by the dashed dotted line, i.e., the gain of vertical polarization, does not have a null point. Therefore, the configuration shown in FIG. 7 can improve the robustness of detection using vertical polarization. FIG. 12 is a diagram showing an example of a 3D plot of the gain shown in FIG. 11. The configuration shown in FIG. 10 can reduce the cost of the device.

[0113] Next, simulation results for other configurations are shown. Figure 13 shows a configuration in which the number of radiating elements on the lower side is changed to two in the configuration shown in Figure 10. Below, the results of simulating the operation of such a configuration are explained. In addition, in the following, explanations that overlap with the explanations of the simulations described above will be simplified or omitted as appropriate.

[0114] Fig. 14 is a diagram showing a graph plotting the gain for each polarization by the radiating elements shown in Fig. 13. Of the curves shown in Fig. 14, the curve shown by the solid line indicates the gain of horizontally polarized waves by the upper six radiating elements shown in Fig. 13. The curve shown by the dashed line indicates the gain of vertically polarized waves by the lower two radiating elements shown in Fig. 13. Furthermore, the curve shown by the dashed line indicates the combined gain of horizontally polarized waves and vertically polarized waves by the upper six radiating elements and the lower two radiating elements shown in Fig. 13.

[0115] As described above, the configuration shown in FIG. 13 is the same as the configuration shown in FIG. 10 except that the number of lower radiating elements is increased to two. With this configuration, as shown in FIG. 14, the direction in which the curve indicated by the dashed-dotted line, i.e., the main lobe of vertically polarized waves, peaks can be changed compared to the example shown in FIG. 11. Furthermore, with this configuration, as shown in FIG. 14, the curve indicated by the dashed-dotted line, i.e., the gain of vertically polarized waves, can be increased in the downward 45° direction (135°) compared to the results shown in FIG. 11. On the other hand, as shown in FIG. 14, the curve indicated by the dashed-dotted line, i.e., the gain of vertically polarized waves, has no null points other than in the front direction (90°). Therefore, the configuration shown in FIG. 13 can also improve the robustness of detection using vertically polarized waves. FIG. 15 shows an example of a 3D plot of the gain shown in FIG. 14.

[0116] Next, simulation results for other configurations are shown. Figure 16 shows a configuration in which the number of radiating elements on the upper side is changed to 12 in the configuration shown in Figure 13. Below, the results of simulating the operation of such a configuration are explained. In addition, in the following, explanations that overlap with the explanations of the simulations described above will be simplified or omitted as appropriate.

[0117] Figure 17 is a diagram showing a graph plotting the gain for each polarization by the radiating elements shown in Figure 16. Of the curves shown in Figure 17, the curve shown by the solid line indicates the gain of horizontally polarized waves by the upper 12 radiating elements shown in Figure 16. The curve shown by the dashed line indicates the gain of vertically polarized waves by the lower two radiating elements shown in Figure 16. Furthermore, the curve shown by the dashed line indicates the combined gain of horizontally polarized waves and vertically polarized waves by the upper 12 radiating elements and the lower two radiating elements shown in Figure 16.

[0118] As shown in FIG. 1, the electronic device 1 according to one embodiment includes two branched receiving antennas, one at the top and one at the bottom, as the first receiving antenna 21 and the other at the second receiving antenna 22. Therefore, the gain of the first receiving antenna 21, located at the top, is approximately half that of when the first receiving antenna 21 is operated alone. For example, in the configuration shown in FIG. 7, a simulation result shows that when the six lower radiating elements are not fed, the maximum gain of horizontally polarized waves is increased by +3 dB (13.7 dBi) compared to the result shown in FIG. 8. To obtain a gain equivalent to the maximum gain achieved by the six radiating elements without halving the gain of the first receiving antenna 21 located at the top, it is necessary to arrange 12 radiating elements, which is six times the number. The solid line curve in FIG. 17 represents the gain of horizontally polarized waves from the upper 12 radiating elements shown in FIG. 16. The gain in the front direction (90°) of the solid line curve in FIG. 17 is approximately 13.4 dBi. However, in this case, since the number of radiating elements is increased, the width of the beam in the front direction (90°) of the curve shown by the solid line in Fig. 17 becomes narrower. Fig. 18 is a diagram showing an example of a 3D plot of the gain shown in Fig. 17.

[0119] Next, simulation results for yet another configuration will be shown. In the above-described electronic device 1, the polarization plane of the first receiving antenna 21 and the polarization plane of the second receiving antenna 22 have been described as being orthogonal. Below, we will explain the results of simulating the operation of a configuration shown in FIG. 7 in which the polarization plane of the upper radiating element and the polarization plane of the lower radiating element are not orthogonal but are the same (parallel). Furthermore, in the following, explanations that overlap with the explanations of the above-described simulations will be appropriately simplified or omitted.

[0120] Fig. 19 is a graph plotting the gain for each polarization of the radiating elements shown in Fig. 16. Of the curves shown in Fig. 19, the curve shown by the solid line indicates the gain of the polarization of the upper six radiating elements. The curve shown by the dashed dotted line indicates the gain of the polarization of the lower six radiating elements. As shown in Fig. 19, even with this configuration, the gain itself in the diagonal downward 45° direction (135°) of the polarization of the lower six radiating elements was relatively good. Fig. 20 is a diagram showing an example of a 3D plot of the gain shown in Fig. 19.

[0121] Fig. 21 is a graph plotting the gain for each polarization in a configuration in which the number of radiating elements is changed in the simulation shown in Fig. 19. Fig. 21 is a graph showing the results of simulating the operation of a configuration in which the number of radiating elements on the upper side remains six and the number of radiating elements on the lower side is only one in the simulation shown in Fig. 19. The curve shown by the solid line indicates the gain of the polarization with the six upper radiating elements. The curve shown by the dashed-dotted line indicates the gain of the polarization with the single lower radiating element. As shown in Fig. 21, even with this configuration, the gain itself in the downward 45° angle (135°) of the polarization with the single lower radiating element was relatively good. However, as shown in Fig. 21, with this configuration, the gain was observed to drop slightly depending on the angle.

[0122] Fig. 22 is a graph plotting the gain for each polarization in a configuration in which the number of radiating elements is changed in the simulation shown in Fig. 19. Fig. 22 is a graph showing the results of simulating the operation of a configuration in which the number of radiating elements on the upper side remains six and the number of radiating elements on the lower side is two in the simulation shown in Fig. 19. The curve shown by the solid line indicates the gain of the polarization with the six upper radiating elements. The curve shown by the dashed dotted line indicates the gain of the polarization with the two lower radiating elements. As shown in Fig. 21, even with this configuration, the gain itself in the diagonal downward 45° direction (135°) of the polarization with the two lower radiating elements was relatively good. However, as shown in Fig. 22, with this configuration, a slight drop in gain was observed depending on the angle.

[0123] As described above, the electronic device 1 (receiving device) according to one embodiment may include a first receiving antenna 21 and a second receiving antenna 22. The first receiving antenna 21 has directivity in a first direction d1. The second receiving antenna 22 has directivity in a second direction d2. Here, the second direction d2 may be a direction different from the first direction d1. The first receiving antenna 21 may maximize its receiving gain when the radio waves received by the first receiving antenna 21 are polarized in a first polarization direction (horizontal polarization). The second receiving antenna 22 may maximize its receiving gain when the radio waves received by the second receiving antenna 22 are polarized in a second polarization direction (vertical polarization). Furthermore, the second polarization direction may be a direction different from the first polarization direction. In the present disclosure, the first receiving antenna 21 may increase its receiving gain as the radio waves received by the first receiving antenna 21 approach the first polarization direction. The second receiving antenna 22 may have a receiving gain that increases as the radio waves received by the second receiving antenna 22 approach the second polarization direction. The second polarization direction may be different from the first polarization direction.

[0124] At least one of the first receiving antenna 21 and the second receiving antenna 22 may be fed from feeding points on the substrate 10 (feeding points 40A to 40d).

[0125] Furthermore, the first receiving antenna 21 and the second receiving antenna 22 may be configured to include patch antennas. In this case, the patch antenna of the first receiving antenna 21 may be fed from the horizontal direction. Furthermore, the patch antenna of the second receiving antenna 22 may be fed from the vertically upward direction to the vertically downward direction. The first direction d1 of the directivity of the first receiving antenna 21 may be a substantially horizontal direction. The second direction d2 of the directivity of the second receiving antenna 22 may be a direction that includes a vertically downward component with respect to the horizontal direction.

[0126] According to the electronic device 1 of an embodiment, the directivity of the receiving antenna can be directed in the front direction and the diagonally downward direction without using an RF switch or the like. Furthermore, according to the electronic device 1 of an embodiment, when directing the directivity of the receiving antenna in the front direction and the diagonally downward direction, different characteristics can be used, such as a high-gain receiving antenna with a narrow beam width on one side and a low-gain receiving antenna with a wide beam width on the other side. According to the electronic device 1 of an embodiment, by changing the polarization of the antenna in two directions, such as the front direction and the diagonally downward direction, interference between elements when directivities in different directions are combined is suppressed. This allows the electronic device 1 of an embodiment to improve design freedom and ease. In particular, according to the electronic device 1 of an embodiment, the power supply circuit is branched into two parts, one for the antenna element in the front direction and one for the antenna element in the downward direction, so that the antenna elements can be treated as separate array antennas. Therefore, according to the electronic device 1 of an embodiment, directivity design is easy. Furthermore, according to the electronic device 1 of an embodiment, it is easy to distribute the feed power in the front direction and the diagonally downward direction, and it is also easy to design the gain. According to the electronic device 1 of one embodiment, the antenna having directivity in the forward direction can be positioned above the ground, and the antenna having directivity in a diagonally downward direction can be positioned below the ground, as the positions of the two branched antennas. With this configuration, the electronic device 1 of one embodiment can suppress interference between elements when including a radome, and can simplify the design. As described above, the electronic device 1 of one embodiment can improve the designability of antenna directivity.

[0127] Next, a description will be given of a radome suitable for the electronic device 1 according to an embodiment. Fig. 23 is a diagram showing an example of the configuration of a radome that can be mounted on the electronic device 1 according to an embodiment.

[0128] As shown in FIG. 1, in the electronic device 1 according to an embodiment, the first transmitting antenna 11 and the second transmitting antenna 12 may be arranged adjacent to each other in the left-right direction, and the third transmitting antenna 13 may be arranged below them. In this case, the electronic device 1 according to an embodiment may include a radome 90 as shown in FIG. 23. FIG. 23 is a diagram showing a state in which the electronic device 1 according to an embodiment, including the substrate 10, is covered with the radome 90. FIG. 23 is a diagram showing the electronic device 1 according to an embodiment as viewed from the side. The direction d1 and the direction d2 shown in FIG. 23 may correspond to the direction d1 and the direction d2 shown in FIG.

[0129] 23, the front surface (surface facing the positive direction of the Z-axis) of a radome 90 suitable for the electronic device 1 according to an embodiment may have a shape that curves downward (negative direction of the Y-axis). By shaping the radome 90 in this way, the distance from the antenna built into the radome 90 to the radome 90 becomes λ0 / 2, and the thickness of the radome 90 can approach a shape that satisfies the relationship λ0 / 2·(εr)^(-0.5). With this arrangement, the electronic device 1 according to an embodiment can obtain advantageous effects by including the radome 90 as shown in FIG.

[0130] As described above, the electronic device 1 according to an embodiment may include a radome 90 that covers at least one of the first receiving antenna 21 and the second receiving antenna 22. The radome 90 may have a shape that reduces the transmission loss of radio waves in the first direction d1 and the second direction d2. The radome 90 may also have a shape such that the distance from at least one of the first receiving antenna 21 and the second receiving antenna to the radome 90 is λ / 2 and the thickness of the radome 90 is λ / 2·(εr)^(-0.5). Here, λ is the wavelength of the received signal received by at least one of the first receiving antenna 21 and the second receiving antenna 22. ε is the dielectric constant of the radome 90. εr is the relative dielectric constant (ε / ε0) of the ratio of the dielectric constant of the radome 90 to the dielectric constant ε0 of a vacuum. In the present disclosure, εr is the relative dielectric constant (ε / ε0) of the ratio of the dielectric constant ε of a medium in which electromagnetic waves exist to the dielectric constant ε0 of a vacuum. In the present disclosure, the dielectric constant ε0′ in air may be used instead of the dielectric constant ε0 in a vacuum.

[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] For example, the electronic device 1 according to the above-described embodiment has been described assuming a device such as a receiving device including a first receiving antenna 21 and a second receiving antenna 22. However, the electronic device according to an embodiment may also be implemented as a device such as a transmitting device including a first transmitting antenna 11, a second transmitting antenna 12, and a third transmitting antenna 13. In this case, the first transmitting antenna 11 and the second transmitting antenna 12 may transmit radio waves having directivity in a first direction d1 with a first polarization. The third transmitting antenna 13 may transmit radio waves having directivity in a second direction d2 different from the first direction d1 with a second polarization. The first transmitting antenna 11 and the second transmitting antenna 12 may transmit signals in a first polarization (e.g., horizontal polarization) using a first feeding arrangement (e.g., horizontal feeding). The third transmitting antenna 13 may transmit signals in a second polarization (e.g., vertical polarization) using a second feeding arrangement (e.g., vertical feeding).

[0133] Furthermore, the above-described embodiments may be implemented as a transmission / reception system including a transmitting device having a transmitting antenna and a receiving device having a receiving antenna. In this case, the transmitting device may include a first transmitting antenna that transmits radio waves having directivity in a first direction with a first polarization, and a second transmitting antenna that transmits radio waves having directivity in a second direction different from the first direction with a second polarization. The receiving device may include a first receiving antenna that has directivity in the first direction, and a second receiving antenna that has directivity in the second direction. The first receiving antenna may have a maximum reception gain when the radio waves received by the first receiving antenna are polarized in the first polarization direction. The second receiving antenna may have a maximum reception gain when the radio waves received by the second receiving antenna are polarized in the second polarization direction.

[0134] Furthermore, the above-described embodiments are not limited to implementation as the electronic device 1 or a transmission / reception system. For example, the above-described embodiments may be implemented as a control method for a device such as the electronic device 1 or a transmission / reception system. Furthermore, for example, the above-described embodiments may be implemented as a control program for a device such as the electronic device 1 or a transmission / reception system. Furthermore, the above-described embodiments may be implemented as a recording medium on which a program executed in a device such as the electronic device 1 or a transmission / reception system is recorded, i.e., a computer-readable recording medium. [Explanation of symbols]

[0135] 1 Electronic equipment 10 Substrate 11 First transmitting antenna 12 Second transmitting antenna 13 Third transmitting antenna 21 First receiving antenna 22 Second receiving antenna 31, 32, 33 Power supply points 40 Power supply point 50 control section 61, 62, 63 Outbound ports 70 inbound port 90 Radome

Claims

1. a first receiving antenna having directivity in a first direction; a second receiving antenna having directivity in a second direction different from the first direction; Equipped with the first receiving antenna has a receiving gain that increases as the polarization direction of the radio wave received by the first receiving antenna approaches the first polarization direction; the second receiving antenna has a receiving gain that increases as the polarization direction of the radio wave received by the second receiving antenna approaches a second polarization direction different from the first polarization direction; the first receiving antenna is fed from a feed point on the substrate; the second receiving antenna is fed from the feed point; The electronic device, wherein the power supply point is connected to one power supply port.

2. the first receiving antenna has a maximum reception gain when the radio wave received by the first receiving antenna is polarized in a first polarization direction; The electronic device according to claim 1 , wherein the second receiving antenna has a maximum reception gain when the radio wave received by the second receiving antenna is polarized in a second polarization direction.

3. a radome covering the first receiving antenna and the second receiving antenna, The electronic device according to claim 1 , wherein the radome has a shape that reduces a transmission loss of radio waves in the first direction and the second direction.

4. 4. The electronic device according to claim 3, wherein the radome has a shape such that a wavelength of a received signal received by at least one of the first receiving antenna and the second receiving antenna is λ, a dielectric constant of the radome is ε, and εr is a relative dielectric constant (ε / ε0) that is a ratio of a dielectric constant ε of a medium in which an electromagnetic wave exists to a dielectric constant ε0 of a vacuum, a distance from at least one of the first receiving antenna and the second receiving antenna to the radome is λ / 2, and a thickness of the radome is λ / 2(εr)^(-0.5).

5. The electronic device according to claim 1 , wherein at least one of the polarized wave in the first polarization direction and the polarized wave in the second polarization direction is any one of linear polarization, elliptical polarization, and circular polarization.

6. the first receiving antenna and the second receiving antenna include patch antennas, the patch antenna of the first receiving antenna is fed horizontally; The electronic device according to claim 1 , wherein the patch antenna of the second receiving antenna is fed vertically.

7. the first direction of the directivity of the first receiving antenna is a substantially horizontal direction, The electronic device according to claim 1 , wherein the second direction of the directivity of the second receiving antenna is a direction including a component in a vertically downward direction relative to a horizontal direction.

8. The electronic device according to claim 1 , wherein the first receiving antenna and the second receiving antenna receive signals of the same frequency.

9. a first transmitting antenna that transmits radio waves having directivity in a first direction with a first polarization; a second transmitting antenna that transmits radio waves with second polarization having directivity in a second direction different from the first direction; Equipped with the first transmitting antenna transmits a signal in the first polarization direction using a first feeding arrangement; the second transmitting antenna transmits a signal in the second polarization direction using a second feeding arrangement; the first transmitting antenna is fed from a feed point on a substrate; the second transmitting antenna is fed from the feeding point; The electronic device, wherein the power supply point is connected to one power supply port.

10. A transmission / reception system including a transmitting device having a transmitting antenna and a receiving device having a receiving antenna, The transmitting device a first transmitting antenna that transmits radio waves having directivity in a first direction with a first polarization; a second transmitting antenna that transmits radio waves with second polarization having directivity in a second direction different from the first direction; Equipped with The receiving device a first receiving antenna having directivity in the first direction; a second receiving antenna having directivity in the second direction; Equipped with the first receiving antenna has a receiving gain that increases as the polarization direction of the radio wave received by the first receiving antenna approaches the first polarization direction; the second receiving antenna has a receiving gain that increases as the polarization direction of the radio wave received by the second receiving antenna approaches a second polarization direction different from the first polarization direction; the first receiving antenna is fed from a feed point on the substrate; the second receiving antenna is fed from the feed point; A transmitting and receiving system, wherein the power feed point is connected to one power feed port.

11. The transmission / reception system according to claim 10 , wherein the first receiving antenna and the second receiving antenna are capable of receiving radio waves at the same time.

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