Radio wave sensor device

Abstract

This radio wave sensor device comprises: a housing having an opening; a transmission / reception unit accommodated in the housing and having a transmission antenna unit capable of transmitting radio waves through the opening, and a reception antenna unit capable of receiving reflected waves through the opening, the transmission / reception unit having directivity for at least one of transmission and reception of the radio waves; a directional control unit; a reflection unit; and a diagnostic unit. The directional control unit controls at least one of the transmission direction and reception direction of the radio waves by the transmission / reception unit. The reflection unit is provided on the inner surface of the housing. The diagnostic unit sets the direction of radio waves to a direction toward the reflection unit by the directional control unit, transmits the radio waves from the transmission antenna unit, and determines a deterioration state of the transmission antenna unit or reception antenna unit on the basis of a reception state of the reflected waves received by the reception antenna unit.

Description

[Technical Field]

[0001] This specification discloses a radio wave sensor device. [Background technology]

[0002] Conventionally, proposed radio wave sensor devices of this type include one that includes an antenna radome that covers a transmitting antenna and a receiving antenna, and detects short-distance reflected waves from the antenna radome with a receiving unit to diagnose normal operation of the sensor, and one that includes a high-frequency circuit unit that connects the transmitting antenna, receiving antenna, transmitting unit, and receiving unit, and detects reflected waves generated in the high-frequency circuit unit as short-distance reflected waves with a receiving unit to diagnose normal operation of the sensor (see, for example, Patent Document 1).In this device, a detection circuit detects low-frequency signals generated by short-distance reflected waves from the antenna radome or high-frequency circuit unit, and if a low-frequency signal is detected, it is determined that the sensor is operating normally, and if a low-frequency signal is not detected, it is determined that the sensor is operating abnormally. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-99912 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-mentioned device requires an antenna radome and a high-frequency circuit section to detect short-distance reflected waves, which makes the device larger and more complicated.

[0005] A primary object of the present disclosure is to appropriately diagnose antenna performance using a simple configuration. [Means for solving the problem]

[0006] The present disclosure has adopted the following means to achieve the above-mentioned main object.

[0007] The radio wave sensor device of the present disclosure includes: a housing having an opening; a transmitting / receiving unit that is housed inside the housing and has a transmitting antenna unit that can transmit radio waves through the opening and a receiving antenna unit that can receive reflected waves through the opening, and has directionality in at least one of transmitting and receiving radio waves; a direction control unit that controls at least one of a transmission direction and a reception direction of radio waves by the transmission / reception unit; a reflecting portion provided on the inner surface of the housing and reflecting radio waves; a diagnostic unit that sets the direction of radio waves toward the reflecting unit using the directional control unit, transmits radio waves from the transmitting antenna unit, and performs degradation diagnosis to determine a degradation state of the transmitting antenna unit or the receiving antenna based on a reception state of the reflected waves received by the receiving antenna unit; The gist of the project is to provide the following:

[0008] The radio wave sensor device disclosed herein includes a transceiver unit having a transmitting antenna unit and a receiving antenna unit inside a housing having an opening, and a directionality control unit that controls at least one of the transmitting direction and receiving direction of radio waves. A reflector is provided on the inner surface of the housing. When diagnosing deterioration of the transmitting antenna unit or the receiving antenna unit, the radio wave sensor device sets the direction of radio waves toward the reflector using the directionality control unit. This allows for appropriate diagnosis of antenna performance with a simple configuration in which a reflector is provided on the inner surface of the housing. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram illustrating the configuration of a radio wave sensor device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a functional block diagram of the radio wave sensor device. [Figure 3] FIG. 2 is a schematic diagram illustrating the configuration of a transmitting antenna unit and a receiving antenna unit. [Figure 4] 10A and 10B are explanatory diagrams illustrating the transmission direction and reception direction of radio waves during a detection operation. [Figure 5] 4 is an explanatory diagram illustrating the transmission direction and reception direction of radio waves during a diagnostic operation. FIG. [Figure 6] 10 is a flowchart illustrating an example of a diagnostic process. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, embodiments of the present disclosure will be described with reference to the drawings.

[0011] Fig. 1 is a schematic configuration diagram of a radio wave sensor device 10 of this embodiment. Fig. 2 is a functional block diagram of the radio wave sensor device 10. As shown in Fig. 1, the radio wave sensor device 10 of this embodiment is mounted on a moving object such as an automatic guided vehicle or a self-propelled robot, and can be used to detect surrounding interfering objects.

[0012] As shown in FIG. 1, the radio wave sensor device 10 includes a housing 11, a radio wave reflector 12, and a radio wave sensor main body 20.

[0013] The housing 11 is a box-shaped member with an opening 11o formed in the front, and has a bottom 11b, a sidewall 11s, and a tapered portion 11t. The tapered portion 11t extends inward from the upper end of the sidewall 11s to surround the opening 11o, and is inclined so as to move away from the bottom 11b as it approaches the opening 11o (center).

[0014] The radio wave reflector 12 is a sheet-like metal plate having a reflective surface on its surface that reflects radio waves, and is attached to the inner surface of the tapered portion 11t so that the vertical direction of the reflective surface is toward the radio wave sensor main body 20 (transmitting antenna portion 22 and receiving antenna portion 23).

[0015] In this embodiment, the radio wave sensor body 20 is configured as a MIMO (Multi-Input Multi-Output) radar sensor. As shown in Fig. 2, the radio wave sensor body 20 includes a transceiver unit 21 including a transmitting antenna unit 22 and a receiving antenna unit 23, and a processing unit 30.

[0016] The transmitting antenna unit 22 has a plurality of (M) transmitting antennas arranged in an array at a predetermined interval dt. The receiving antenna unit 23 has a plurality of (N) receiving antennas arranged in an array in the same direction as the transmitting antennas at an interval dr different from the interval dt between the transmitting antennas. By transmitting signals from the M transmitting antennas and receiving them simultaneously with the N receiving antennas, the radar device can be considered to receive signals with M×N virtual receiving antennas for one transmitting antenna. In this embodiment, as shown in FIG. 3, the transmitting antenna unit 22 and the receiving antenna unit 23 are formed on the same printed circuit board 25. Note that the transmitting antenna unit 22 and the receiving antenna unit 23 may each be formed on separate printed circuit boards.

[0017] The transmitter / receiver 21 branches the transmission signal from the processing unit 30 into M transmission signals, which is the number of transmission antennas of the transmitting antenna unit 22, and outputs them to each transmitting antenna. The transmitter / receiver 21 also inputs N reception signals from each reception antenna of the receiving antenna unit 23 and outputs them to the processing unit 30.

[0018] The processing unit 30 includes a microcomputer or IC including a CPU, ROM, RAM, input / output interface, etc. The processing unit 30 includes functional blocks configured by at least one of hardware such as a CPU, ROM, RAM, and IC, and software installed in the ROM, including a directionality control unit 31, a detection unit 32, a storage unit 33, and a diagnosis unit 34.

[0019] The directionality control unit 31 controls the transmission direction and reception direction of radio waves from the transmitter / receiver unit 21 by beamforming. The transmission direction is controlled by adjusting the phase difference of radio waves (transmission signals) transmitted from the M transmission antennas of the transmission antenna unit 22 so that the transmitted radio waves are concentrated in a specific direction. The reception direction is controlled by receiving radio waves coming from a specific direction with the N reception antennas of the reception antenna unit 23 and detecting the phase difference of the received signals. Note that the directionality control unit 31 may be configured to control only either the transmission direction or the reception direction.

[0020] The detection unit 32 transmits radio waves from the opening 11o on the front of the housing 11 using the transmission / reception unit 21 and receives reflected waves that enter the opening 11o from an object (interfering object), thereby detecting the presence or absence of an object and its position based on the received signal received by the transmission / reception unit 21. FIG. 4 is an explanatory diagram illustrating the transmission direction and reception direction of radio waves during detection operation. As shown in the figure, during detection operation, in order to ensure a detection range, the directivity has a certain spread θs, θr, and the directivity and transmission / reception direction are set so that radio waves are transmitted and received toward the front (11o). Note that the directivity can be adjusted by setting the number of transmitting antennas that transmit radio waves and the number of receiving antennas that receive radio waves.

[0021] The diagnostic unit 34 periodically self-diagnoses deterioration over time in the antenna performance (antenna gain and impedance) of the transmitting antenna unit 22 and the receiving antenna unit 23. Fig. 5 is an explanatory diagram illustrating the transmitting direction and receiving direction of radio waves during diagnostic operation. As shown in the figure, during diagnostic operation, the directivity and transmitting / receiving direction are set so that the spread of directivity θs, θr is smaller than during detection operation, and radio waves are transmitted and received toward the radio wave reflector 12.

[0022] Next, the operation of the radio wave sensor device 10 configured as described above will be described. In particular, the diagnostic process executed by the diagnostic unit 34 will be described. FIG. 6 is a flowchart illustrating an example of the diagnostic process. In the diagnostic process, the CPU of the processing unit 30 first determines whether a predetermined period has elapsed since the previous diagnosis (step S100). The predetermined period is set to, for example, three months or six months. If the diagnostic unit 34 determines that the predetermined period has not elapsed since the previous diagnosis, as shown in FIG. 5, the diagnostic unit 34 sets the transmission direction and reception direction of the radio wave toward the radio wave reflector 12 and sets the directivity (step S110), controls the directionality control unit 31 so that the transmitting antenna unit 22 transmits the radio wave in the set transmission direction with the set directivity, and outputs a transmission signal to the transceiver unit 21 (step S120). Next, the diagnostic unit 34 determines whether a reflected wave has been received from the reception direction set by the receiving antenna unit 23 (step S130). When the diagnostic unit 34 determines that a reflected wave has been received from the set receiving direction, it acquires a reception strength δ from the received signal (step S140) and determines whether the acquired reception strength δ is greater than a threshold δref (step S150). Here, the threshold δref is a threshold for determining whether the antenna performance of the transmitting antenna unit 22 and the receiving antenna unit 23 is sufficient, and is set to a value obtained in advance through experiments or the like. When the diagnostic unit 34 determines that the reception strength δ is greater than the threshold δref, it determines that the antenna performance is sufficient and that there is no deterioration over time in the transmitting antenna unit 22 or the receiving antenna unit 23 (step S160), and ends the diagnostic process. On the other hand, when the diagnostic unit 34 determines that the reception strength δ is equal to or less than the threshold δref, it determines that the antenna performance is insufficient and that there is deterioration over time in the transmitting antenna unit 22 or the receiving antenna unit 23 (step S170), outputs a signal indicating that there is deterioration to the outside (step S180), and ends the diagnostic process.

[0023] In this way, during detection operation, the radio wave sensor device 10 detects surrounding objects by transmitting and receiving radio waves through the opening 11o facing forward, and during diagnosis operation, it transmits and receives radio waves in the direction of transmission and reception toward the radio wave reflector 12 to self-diagnose deterioration over time of the transmitting antenna section 22 and the receiving antenna section 23. This makes it possible to self-diagnose antenna performance with a simple configuration in which the radio wave reflector 12 is simply provided on the tapered section 11t of the housing 11.

[0024] Here, the correspondence between the main elements of the embodiment and the main elements of the present disclosure described in the claims will be described. That is, the opening 11o corresponds to an opening, the housing 11 corresponds to a housing, the directionality control unit 31 corresponds to a directionality control unit, the radio wave reflector 12 corresponds to a reflecting unit, and the diagnostic unit 34 corresponds to a diagnostic unit.

[0025] It goes without saying that the present disclosure is not limited to the above-described embodiments, and can be embodied in various forms as long as they fall within the technical scope of the present disclosure.

[0026] The radio wave sensor device disclosed herein described above includes a transceiver unit having a transmitting antenna unit and a receiving antenna unit inside a housing having an opening, and a directionality control unit that controls at least one of the transmitting and receiving directions of radio waves. A reflector is provided on the inner surface of the housing. When diagnosing deterioration of the transmitting antenna unit or the receiving antenna unit, the radio wave sensor device uses the directionality control unit to set the direction of radio waves toward the reflector. This allows for appropriate diagnosis of antenna performance with a simple configuration in which a reflector is provided on the inner surface of the housing.

[0027] In the radio wave sensor device of the present disclosure, the housing may have a tapered portion that extends inward from the end of the side portion toward the opening and that slopes away from the transmitting antenna portion and the receiving antenna portion as it approaches the opening, and the reflector may be provided on the inner surface of the tapered portion. In this way, sufficient openings for transmitting and receiving radio waves are secured in front of the transmitting antenna portion and the receiving antenna portion, and radio waves can be transmitted to and received from the reflector as needed to self-diagnose antenna performance.

[0028] In the radio wave sensor device of the present disclosure, the transmitting antenna unit and the receiving antenna unit may be provided on the same printed circuit board, which allows the radio wave sensor device to have a simpler configuration and to be more compact.

[0029] Furthermore, in the radio wave sensor device of the present disclosure, the diagnostic unit may automatically perform the degradation diagnosis at a predetermined timing, thereby enabling automatic diagnosis of degradation of antenna performance at any timing. [Industrial Applicability]

[0030] The present disclosure is applicable to industries such as the manufacturing of radio wave sensor devices. [Explanation of symbols]

[0031] 10 Radio wave sensor device, 11 housing, 11b bottom, 11o opening, 11s side wall portion, 11t tapered portion, 12 radio wave reflector, 20 radio wave sensor main body, 21 transmitting / receiving portion, 22 transmitting antenna portion, 23 receiving antenna portion, 25 printed circuit board, 30 processing portion, 31 directional control portion, 32 detection portion, 33 memory portion, 34 diagnosis portion.

Claims

1. a housing having an opening; a transmitting / receiving unit that is housed inside the housing and has a transmitting antenna unit that can transmit radio waves through the opening and a receiving antenna unit that can receive reflected waves through the opening, and has directivity in at least one of transmitting and receiving radio waves; a direction control unit that controls at least one of a transmission direction and a reception direction of radio waves by the transmission / reception unit; a reflecting portion provided on the inner surface of the housing and reflecting radio waves; a diagnostic unit that sets the direction of radio waves toward the reflecting unit using the directional control unit, transmits radio waves from the transmitting antenna unit, and performs degradation diagnosis to determine a degradation state of the transmitting antenna unit or the receiving antenna unit based on the reception intensity of the reflected wave received by the receiving antenna unit; A radio wave sensor device comprising:

2. The radio wave sensor device according to claim 1, the housing has a tapered portion that extends inward from an end of a side surface portion toward the opening and is inclined so as to move away from the transmitting antenna portion and the receiving antenna portion as it approaches the opening, The reflecting portion is provided on the inner surface of the tapered portion. Radio wave sensor device.

3. 3. The radio wave sensor device according to claim 1, The transmitting antenna unit and the receiving antenna unit are provided on the same printed circuit board. Radio wave sensor device.

4. The radio wave sensor device according to any one of claims 1 to 3, The diagnosis unit automatically performs the deterioration diagnosis at a predetermined timing. Radio wave sensor device.

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