JP7040569B2 - Wireless communication equipment, wireless communication systems, wireless communication methods and wireless communication programs - Google Patents

Description

The present invention relates to wireless communication devices, wireless communication systems, wireless communication methods and wireless communication programs.

Conventionally, in a wireless communication system, it has been required to ensure communication quality without being influenced by other systems or affecting other systems. For example, Patent Document 1 proposes a technique for reducing the influence of external interference waves in order to ensure communication quality. Specifically, the system described in Patent Document 1 includes a first drone that measures desired wave power from a base station and a second drone that measures interference wave power from another system. .. Then, the interference wave power in the first drone is obtained from the interference wave power measured by the second drone and the propagation loss due to the distance from the first drone, and this is subtracted from the measured power of the first drone. Therefore, it is configured to accurately measure the desired wave power.

Japanese Unexamined Patent Publication No. 2018-96928

In the system of Patent Document 1, two drones are used to perform a process of subtracting the interference wave power from the measured power to reduce the influence of the interference wave. In this case, complicated signal processing is required, and a plurality of drones and a device for performing subtraction processing are required, which leads to complication of the system.

The present invention is based on the above-mentioned problems, and is a wireless communication device, a wireless communication system, a wireless communication method, and a wireless communication capable of reducing the influence of interference waves without causing system complexity. The purpose is to provide a program.

When the wireless communication device according to the present invention detects an interference wave by an antenna that transmits and receives radio waves, an interference wave detection unit that detects the presence or absence of an interference wave based on the radio waves received by the antenna, and an interference wave detection unit. It is equipped with an interference wave information acquisition unit that acquires the level and arrival direction of the interference wave, and an antenna control unit that performs null steering to direct the null point of the antenna to the arrival direction when the interference wave level is equal to or higher than the first threshold value. When the level of the interference wave is equal to or higher than the first threshold value and the antenna control unit cannot perform null steering, the attitude of the wireless communication device is changed, or the antenna is moved or rotated . Another wireless communication device according to the present invention interferes with an antenna that transmits and receives radio waves from a transmitter / receiver, an interference wave detection unit that detects the presence / absence of an interference wave based on the radio waves received by the antenna, and an interference wave detection unit. The interference wave information acquisition unit that acquires the level and arrival direction of the interference wave when a wave is detected, and the null steering and antenna that direct the null point of the antenna to the arrival direction when the interference wave level is equal to or higher than the first threshold value. It is equipped with an antenna control unit that performs beam steering to direct the main beam to the transmitter / receiver. Another wireless communication device according to the present invention detects an interference wave by an antenna that transmits and receives radio waves, an interference wave detection unit that detects the presence or absence of an interference wave based on the radio wave received by the antenna, and an interference wave detection unit. In this case, an interference wave information acquisition unit that acquires the interference wave level and the arrival direction, and an antenna control unit that performs null steering to direct the null point of the antenna to the arrival direction when the interference wave level is equal to or higher than the first threshold value. The antenna control unit stops the transmission of radio waves from the antenna when the level of the interference wave is equal to or higher than the second threshold value larger than the first threshold value.
The wireless communication system according to the present invention includes any of the above wireless communication devices and a transceiver capable of communicating with the wireless communication device.
The wireless communication method according to the present invention includes a step of detecting the presence or absence of an interference wave based on the radio wave received by the antenna, a step of acquiring the level and the direction of arrival of the interference wave when the interference wave is detected, and a step of acquiring the interference wave. Radio when the level is equal to or higher than the first threshold and the null steering is performed to direct the null point of the antenna in the arrival direction, and when the level of the interference wave is equal to or higher than the first threshold and the null steering cannot be performed. It has a step of changing the posture of the communication device or moving or rotating the antenna . Another wireless communication method according to the present invention is a step of detecting the presence or absence of an interference wave based on the radio wave received from the transmitter / receiver by the antenna, and a step of acquiring the level and the arrival direction of the interference wave when the interference wave is detected. And, when the level of the interference wave is equal to or higher than the first threshold value, there is a step of performing null steering for directing the null point of the antenna in the arrival direction and beam steering for directing the main beam of the antenna toward the transmitter / receiver. Another wireless communication method according to the present invention includes a step of detecting the presence or absence of an interference wave based on the radio wave received by the antenna, and a step of acquiring the level and the direction of arrival of the interference wave when the interference wave is detected. The step of performing null steering to direct the null point of the antenna in the arrival direction when the wave level is equal to or higher than the first threshold, and the step from the antenna when the level of the interference wave is higher than the first threshold and higher than the second threshold. It has a step of stopping the transmission of radio waves.
The wireless communication program according to the present invention causes a processor of a wireless communication device to execute any of the above wireless communication methods .

According to the wireless communication device, the wireless communication system, the wireless communication method, and the wireless communication program according to the present invention, when the level of the interference wave is equal to or higher than the first threshold value, null steering is performed to direct the null point of the antenna in the arrival direction. Therefore, the influence of the interference wave can be reduced without incurring the complexity of the system.

It is a schematic block diagram of the wireless communication system which concerns on Embodiment 1. FIG. It is a block diagram which shows the schematic structure of the mobile terminal which concerns on Embodiment 1. FIG. It is a flowchart which shows the flow of the interference suppression processing which concerns on Embodiment 1. It is a figure explaining the interference suppression process which concerns on Embodiment 1. FIG. It is a figure explaining the interference suppression process which concerns on Embodiment 2. It is a flowchart which shows the flow of the interference suppression processing which concerns on Embodiment 2. It is a figure explaining the interference suppression process which concerns on Embodiment 3. It is a flowchart which shows the flow of the interference suppression processing which concerns on Embodiment 3. It is a figure explaining the interference suppression process which concerns on modification 1. FIG.

Embodiment 1.
FIG. 1 is a schematic configuration diagram of a wireless communication system 100 according to the first embodiment. The wireless communication system 100 in the present embodiment is used when inspecting infrastructure equipment such as a bridge or a tunnel of a viaduct, for example. As shown in FIG. 1, the wireless communication system 100 of the present embodiment includes a mobile terminal 1 which is a wireless communication device and a transmitter / receiver 2. The mobile terminal 1 and the transmitter / receiver 2 perform data communication by a wireless LAN or a wireless communication technology of a proprietary standard.

The mobile terminal 1 of the present embodiment is an unmanned small airplane, which is also called a drone. The mobile terminal 1 has an autonomous flight function and an autonomous attitude control function, and can autonomously realize stable flight. The mobile terminal 1 flies around the infrastructure equipment and acquires inspection data such as image information of the infrastructure equipment. The transceiver 2 is also referred to as a radio, and controls the mobile terminal 1 by transmitting a control signal according to the operation of the operator to the mobile terminal 1. Further, the transceiver 2 receives the inspection data acquired by the mobile terminal 1 and performs inspection processing of the infrastructure equipment.

As shown in FIG. 1, there may be another wireless communication system 200 near the inspection point of the wireless communication system 100 of the present embodiment. The other wireless communication system 200 is an ETC tollhouse 201, a wireless LAN 202, or the like. For the purpose of sharing frequency resources, the frequency band near 5.7 GHz is used in the ETC tollhouse 201 or the wireless LAN 202 of the wireless communication system 200. The radio waves transmitted and received by the wireless communication system 200 are interference waves when the wireless communication system 100 is used. Further, the radio waves transmitted and received by the wireless communication system 100 become interference waves when the wireless communication system 200 is used. Interference waves affect stable communication quality. That is, the wireless communication system 100 is affected by the interference wave from the wireless communication system 200, or the communication quality of the wireless communication system 200 is affected.

Therefore, in the wireless communication system 100 of the present embodiment, in the mobile terminal 1, the influence on the communication quality (interference) due to the interference wave from the other wireless communication system 200 and the influence on the other wireless communication system 200 (interference). Interference suppression processing is performed to suppress interference).

FIG. 2 is a block diagram showing a schematic configuration of the mobile terminal 1 according to the first embodiment. As shown in FIG. 2, the mobile terminal 1 includes a control device 10, a drive device 11, a sensor group 12, an inspection device 13, and an antenna 14. Further, the mobile terminal 1 includes a battery such as a lithium ion polymer secondary battery or a lithium ion secondary battery (not shown), and the battery supplies electric power required for each device.

The drive device 11 includes a motor for flying the mobile terminal 1, a propeller, and an ESC (Electric Speed Controller) that controls the rotation speed of the motor. The drive device 11 enables the mobile terminal 1 to fly and rotate.

The sensor group 12 is composed of a GNSS (Global Navigation Satellite System), an acceleration sensor, a magnetic sensor, an altitude meter, and the like. Send.

The inspection device 13 is a device that acquires inspection data such as image information of infrastructure equipment in the inspection area. The inspection device 13 is, for example, a camera, an infrared sensor, or an ultrasonic sensor. The type and configuration of the sensor may be changed depending on the object to be inspected. Further, the inspection device 13 has a function of changing the direction of the sensor by a motor, and can change the direction of the sensor according to an inspection command received from the control device 10.

The antenna 14 is an antenna that receives radio waves from the transceiver 2 and transmits the radio waves to the transceiver 2. The antenna 14 is a directional antenna, for example, a planar phased array antenna having 5 × 5 antenna elements. The antenna 14 can control the radiation pattern by changing the phase and amplitude of the feeding to each antenna element.

The control device 10 controls the operation of each part of the mobile terminal 1. The control device 10 includes a processor such as a CPU and a memory such as a RAM, a ROM, or a flash memory. Further, the control device 10 includes an attitude control unit 101, a radio control unit 102, an RF transmission circuit 103, an RF reception circuit 104, an interference wave detection unit 105, an interference wave information acquisition unit 106, and an antenna control unit 107. And have. The attitude control unit 101, the radio control unit 102, the interference wave detection unit 105, the interference wave information acquisition unit 106, and the antenna control unit 107 are realized by the processor executing software (program), or are realized by an ASIC or the like. It is realized by a dedicated circuit.

The attitude control unit 101 performs an operation for controlling the flight and attitude of the mobile terminal 1 using the sensor data acquired from the sensor group 12, and transmits a control command to the drive device 11. The posture of the mobile terminal 1 includes the angle and position of the mobile terminal 1. Further, the attitude control unit 101 transfers the sensor data acquired from the sensor group 12 to the wireless control unit 102, acquires the control command of the mobile terminal 1 by the transceiver 2 from the wireless control unit 102, and gives the drive device 11 a control command. To transfer.

The wireless control unit 102 performs reception processing on the reception signal acquired by the RF reception circuit 104, converts it into a control command for operating the mobile terminal 1, and transfers it to the attitude control unit 101. Further, the wireless control unit 102 performs reception processing on the received signal acquired by the RF reception circuit 104, converts it into an inspection command for controlling the inspection device 13, and transfers it to the inspection device 13. Further, the wireless control unit 102 performs transmission processing on the sensor data of the mobile terminal 1 acquired from the attitude control unit 101 and the inspection data acquired from the inspection device 13, converts them into transmission signals, and performs an RF transmission circuit. Send to 103.

The RF transmission circuit 103 converts the transmission signal acquired from the radio control unit 102 into a transmission radio wave and transfers it to the antenna 14. The RF receiving circuit 104 converts the received radio wave received by the antenna 14 into a received signal and transfers it to the radio control unit 102.

The interference wave detection unit 105 detects the presence or absence of an interference wave in the inspection area in the interference suppression process. Specifically, the interference wave detection unit 105 acquires a received signal from the RF reception circuit 104 during the interference suppression process, demodulates the acquired received signal, and measures the SN ratio of the demodulated signal. Then, when the measured SN ratio is equal to or less than a predetermined value, the interference wave detection unit 105 determines that the interference wave has been detected.

When the interference wave is detected by the interference wave detection unit 105, the interference wave information acquisition unit 106 acquires the arrival direction and level of the detected interference wave. Specifically, the interference wave information acquisition unit 106 estimates the arrival direction of the interference wave based on the received signal of each antenna element of the antenna 14. The estimation of the direction of arrival is performed using a known high-resolution algorithm such as the MUSIC (Multiple Signal Classification) method or the ESPRIT (Estimation of Signal Parameters via Rotation Invariance Techniques) method. Further, the interference wave information acquisition unit 106 measures the power of the received interference wave and obtains the interference wave level from the power.

The antenna control unit 107 controls the radiation pattern of the antenna 14. Specifically, when the antenna control unit 107 detects an interference wave in the interference wave suppression process and the interference wave level is equal to or higher than the first threshold value, the antenna control unit 107 sends and receives a null steering that directs a null point to the interference source. Perform beam steering to direct the main beam to the machine 2. At this time, the antenna control unit 107 calculates and synthesizes the complex weight W so as to have a directivity such that the null point is directed to the arrival direction of the interference wave and the main beam is directed to the transceiver 2. The complex weight W is a weight that adjusts the phase and amplitude of the feeding to each antenna element of the antenna 14. For the directivity calculation, for example, the DCMP (Directionally Constrained Minimization of power) method is used. The antenna control unit 107 estimates the direction of arrival of radio waves from the transceiver 2 in order to specify the position of the transceiver 2 before performing beam steering for directing the main beam to the transceiver 2. The estimation of the arrival direction is performed in the same manner as the estimation of the arrival direction of the interference wave described above.

Further, the antenna control unit 107 stops the transmission of the radio wave from the antenna 14 when the interference wave is detected and the interference wave level is equal to or higher than the second threshold value larger than the first threshold value. When the interference wave level is equal to or higher than the second threshold value, it is considered that the distance between the mobile terminal 1 and the interference source is short. In this case, it is considered that the communication between the mobile terminal 1 and the transceiver 2 may affect the other wireless communication system 200 by the interference wave, so that the transmission of the radio wave from the mobile terminal 1 is stopped. The first threshold value and the second threshold value are preset and stored in the memory of the control device 10. The first threshold and the second threshold are set based on an acceptable interference wave power value (adjacent channel interference or spurious response) defined by a wireless communication standard such as the narrow range communication system standard (ARIB STD T75). Specifically, the value obtained by taking an arbitrary first margin from the allowable value specified in the standard is set as the first threshold value, and the second margin smaller than the first margin is taken from the allowable value specified in the standard. The value is set as the second threshold value. If the second threshold value is set to the allowable value specified in the standard, other wireless communication systems 200 may not be able to operate. Therefore, it is necessary to set a margin for the allowable value for the second threshold value as well. be.

Further, the first threshold value and the second threshold value may be changed according to the distance from the interference source. In this case, the antenna control unit 107 calculates an approximate distance from the interference source from the power of the received interference wave, and from the calculated distance, how much the radio wave transmitted by the mobile terminal 1 is in the other wireless communication system 200. Estimate whether it will be the reception level. Then, in consideration of interference, the estimated reception level may be compared with the allowable value specified in the standard, and the first margin and the second margin may be set according to the comparison result. Specifically, the larger the difference between the estimated reception level and the permissible value specified in the standard, the smaller the first margin and the second margin are set. In addition, when interference is taken into consideration, the power of the received interference wave is compared with the saturation point level of the nonlinear element in the mobile terminal 1 and based on the non-saturation level (the level at which the mobile terminal 1 can operate as a receiver). , The first threshold and the second threshold may be set.

The transceiver 2 includes an antenna (not shown), an RF transmission circuit, an RF reception circuit, a control device, an operation unit operated by an operator, and a display unit that displays data and the like received from the mobile terminal 1. Be prepared. The transceiver 2 transmits a control signal for controlling the mobile terminal 1 in response to an operation of the operation unit, and receives inspection data from the mobile terminal 1. The transceiver 2 may be a dedicated radio for the mobile terminal 1 or an information terminal such as a smartphone or tablet.

FIG. 3 is a flowchart showing the flow of the interference suppression process according to the first embodiment. This process is executed by the control device 10 of the mobile terminal 1 before starting the inspection process. In this process, first, an operation of detecting the presence or absence of an interference wave in the inspection area is performed (S1). Here, the mobile terminal 1 repeatedly rotates and moves up and down in the inspection area so that interference waves from the horizontal direction and the vertical direction can be detected.

Then, it is determined whether or not the interference wave is detected by the interference wave detection unit 105 (S2). Here, if no interference wave is detected (S2: NO), this process is terminated and an inspection process is performed. On the other hand, when the interference wave is detected (S2: YES), the interference wave information acquisition unit 106 acquires the direction of arrival of the interference wave and the interference wave level (S3).

Subsequently, it is determined whether or not the acquired interference wave level is equal to or higher than the first threshold value (S4). When the interference wave level is less than the first threshold value (S4: NO), it is determined that the influence of the interference wave is small, and this process is terminated and the inspection process is performed. On the other hand, when the interference wave level is equal to or higher than the first threshold value (S4: YES), it is determined whether or not the interference wave level is equal to or higher than the second threshold value larger than the first threshold value (S5).

When the interference wave level is less than the second threshold value (S5: NO), the antenna control unit 107 performs null steering and beam steering of the antenna 14. Specifically, first, the null point is directed in the direction of arrival of the interference wave (S6). Then, the main beam is directed in the direction of the transceiver 2 (S7). As a result, the influence of the interference wave in the inspection process can be suppressed.

On the other hand, when the interference wave level is equal to or higher than the second threshold value (S5: YES), it is determined that the distance to the interference source is short and there is a risk of interference, and the antenna control unit 107 stops the transmission of radio waves from the antenna 14. (S8). After that, this process ends.

FIG. 4 is a diagram illustrating the interference suppression process according to the first embodiment. As shown in FIG. 4, in the present embodiment, when the mobile terminal 1 detects the interference wave 210, the directivity of the antenna 14 of the mobile terminal 1 is controlled based on the level and the arrival direction of the interference wave 210. Specifically, when the interference wave level is equal to or higher than the first threshold value, a null point is directed in the arrival direction of the interference wave 210 as shown by the dotted line in FIG. 4, and the transmitter / receiver 2 is shown by the alternate long and short dash line in FIG. The main beam is directed at. As a result, the influence of the interference wave 210 from the other wireless communication system 200 can be reduced with a simple configuration without complicating the wireless communication system 100. As a result, deterioration of the communication quality of the wireless communication system 100 can be suppressed.

Further, when it is determined from the interference wave level that the distance between the mobile terminal 1 and the interference source is short, the transmission of the radio wave from the mobile terminal 1 is stopped, so that the interference wave to the other wireless communication system 200 is generated. The impact can be reduced. As a result, deterioration of communication quality in the other wireless communication system 200 can be suppressed.

Embodiment 2.
The second embodiment will be described. The wireless communication system 100 of the second embodiment is different from the first embodiment in that the attitude control of the mobile terminal 1 is performed in the interference suppression process. The configuration of the mobile terminal 1 and the transceiver 2 is the same as that of the first embodiment.

FIG. 5 is a diagram illustrating the interference suppression process according to the second embodiment. As shown in FIG. 5, also in the present embodiment, when the mobile terminal 1 detects the interference wave 210, the directivity of the antenna 14 of the mobile terminal 1 is controlled based on the level and the arrival direction of the interference wave 210. Specifically, when the interference wave level is equal to or higher than the first threshold value, a null point is directed in the arrival direction of the interference wave 210 as shown by the dotted line in FIG. 5, and the transmitter / receiver 2 is shown by the alternate long and short dash line in FIG. The main beam is directed at. Here, depending on the positional relationship between the mobile terminal 1 and the interference source and the posture of the mobile terminal 1, it may not be possible to direct the null point in the direction of arrival of the interference wave even if the feeding adjustment to the antenna 14 is performed. Therefore, the mobile terminal 1 of the present embodiment performs attitude control such as moving or rotating the mobile terminal 1 when the null point cannot be directed in the direction of arrival of the interference wave only by adjusting the power supply to the antenna 14. It is composed. Attitude control here includes not only rotating the mobile terminal 1 to change the angle, but also moving the mobile terminal 1 to change the position. In the example of FIG. 5, as shown by the white arrow, the mobile terminal 1 is rotated and tilted to change the direction in which the null point is directed.

The antenna control unit 107 determines whether or not null steering is possible, for example, as follows. First, the antenna control unit 107 performs null steering by adjusting the power supply to the antenna 14, and compares the interference wave level received by the mobile terminal 1 with an arbitrary threshold value. At this time, if the interference wave level is equal to or lower than the threshold value, it is determined that null steering by the antenna control unit 107 is possible. On the other hand, when the interference wave level is larger than the threshold value, that is, when the interference wave level does not decrease, it is determined that null steering by the antenna control unit 107 is impossible. The threshold value used here is set with reference to the saturation point of the nonlinear element for the interference wave received by the mobile terminal 1. On the other hand, for the interference wave given to the other wireless communication system 200, the reception level in the other wireless communication system 200 is estimated from the radiation pattern or the distance from the other wireless communication system 200, and the value corresponds to the reception level. Is set.

FIG. 6 is a flowchart showing the flow of the interference suppression process according to the second embodiment. The processing of steps S1 to S5 is the same as that of the first embodiment. When the interference wave level is less than the second threshold value (S5: NO), the antenna control unit 107 performs null steering and beam steering of the antenna 14. Here, first, it is determined whether or not null steering by the antenna control unit 107 is possible (S11). Then, when null steering by the antenna control unit 107 is possible (S11: YES), that is, when the null point can be directed in the direction of arrival of the interference wave by adjusting the power supply to the antenna 14, the process proceeds to step S6. Then, as in the first embodiment, null steering is performed by the antenna control unit 107.

On the other hand, when null steering by the antenna control unit 107 is not possible (S11: NO), that is, when the null point cannot be directed in the direction of arrival of the interference wave only by adjusting the power supply to the antenna 14, the posture of the mobile terminal 1 is changed. It is changed (S12). In the present embodiment, the antenna control unit 107 and the attitude control unit 101 are communicably connected, and a maneuvering command is transmitted from the antenna control unit 107 to the attitude control unit 101. The maneuvering command in this case is to move or rotate the mobile terminal 1 so that the null point of the antenna 14 faces in the direction of arrival of the interference wave. The attitude control unit 101 receives a maneuvering command from the antenna control unit 107 and transfers the maneuvering command to the drive device 11. As a result, the posture of the mobile terminal 1 is changed. After that, the null steering in step S6 and the beam steering in step S7 are performed as in the first embodiment, and this process is completed.

As described above, in the present embodiment, even when it is difficult to adjust the radiation pattern to an appropriate level only by adjusting the power supply to the antenna 14, the influence of the interference wave is reduced by changing the posture of the mobile terminal 1. It is possible to suppress the deterioration of the communication quality of the wireless communication system 100.

In the above embodiment, the attitude control of the mobile terminal 1 is performed during null steering, but the attitude control of the mobile terminal 1 is performed during beam steering or both null steering and beam steering. May be good. Alternatively, when the antenna 14 is movable and null steering or beam steering by the antenna control unit 107 is not possible, the antenna 14 may be moved or rotated in place of or in addition to the attitude control of the mobile terminal 1.

Embodiment 3.
The third embodiment will be described. The wireless communication system 100 of the third embodiment is different from the first embodiment in that a movement instruction to the transceiver 2 is given in the interference suppression process. The configuration of the mobile terminal 1 and the transceiver 2 is the same as that of the first embodiment.

FIG. 7 is a diagram illustrating the interference suppression process according to the third embodiment. As shown in FIG. 7, even in the present embodiment, when the mobile terminal 1 detects the interference wave 210, the directivity of the antenna 14 of the mobile terminal 1 is controlled based on the level and the arrival direction of the interference wave 210. Specifically, when the interference wave level is equal to or higher than the first threshold value, a null point is directed in the arrival direction of the interference wave 210 as shown by the dotted line in FIG. 7, and the transmitter / receiver 2 is shown by the alternate long and short dash line in FIG. The main beam is directed at. Here, depending on the positional relationship between the mobile terminal 1 and the transceiver 2, the main beam may not be directed to the transceiver 2 even if the power supply to the antenna 14 is adjusted. Therefore, the mobile terminal 1 of the present embodiment has a configuration in which the mobile terminal 1 instructs the transceiver 2 to move when the main beam cannot be directed to the transceiver 2 only by adjusting the power supply to the antenna 14. It has become. In the example of FIG. 7, the transceiver 2 is moved as shown by the white arrow, and the main beam is directed to the transceiver 2.

The determination of whether or not beam steering is possible by the antenna control unit 107 is performed in the same manner as the determination of whether or not null steering is possible in the second embodiment. Specifically, first, the antenna control unit 107 performs beam steering by adjusting the power supply, and compares the radio wave level received from the transceiver 2 by the mobile terminal 1 with an arbitrary threshold value. Then, when the radio wave level from the transceiver 2 is equal to or higher than the threshold value, it is determined that the beam steering by the antenna control unit 107 is possible. On the other hand, when the radio wave level from the transceiver 2 is less than the threshold value, that is, when the radio wave level does not rise, it is determined that beam steering by power supply adjustment is impossible.

FIG. 8 is a flowchart showing the flow of the interference suppression process according to the third embodiment. The processing of steps S1 to S6 is the same as that of the first embodiment. When null steering is performed in step S6, it is determined whether or not beam steering by the antenna control unit 107 is possible (S21). Then, when the beam steering by the antenna control unit 107 is possible (S21: YES), that is, when the main beam can be directed to the transceiver 2 by adjusting the power supply to the antenna 14, the process proceeds to step S7. Then, as in the first embodiment, beam steering by the antenna control unit 107 is performed.

On the other hand, if beam steering by the antenna control unit 107 is not possible (S21: NO), that is, if the main beam cannot be directed to the transceiver 2 only by adjusting the power supply to the antenna 14, a movement instruction is transmitted to the transceiver 2. (S22). In the present embodiment, the antenna control unit 107 and the wireless control unit 102 are communicably connected, and instruction data is transmitted from the antenna control unit 107 to the wireless control unit 102. The instruction data in this case indicates the moving direction and the moving distance of the transceiver 2 so that the main beam is directed to the transceiver 2. Further, the instruction data may be linked with GPS information or map information. Since the moving direction and moving distance of the transceiver 2 depend on the antenna pattern of the mobile terminal 1 and the transceiver 2 and the surrounding building environment, they may be set in advance by performing simulation and actual measurement.

The wireless control unit 102 performs transmission processing on the instruction data acquired from the antenna control unit 107, converts it into a transmission signal, and transmits it to the RF transmission circuit 103. The RF transmission circuit 103 converts the transmission signal received from the radio control unit 102 into a transmission radio wave and transmits it to the antenna 14. Then, the operator of the transceiver 2 that receives the signal from the mobile terminal 1 moves according to the instruction. After that, the beam steering of step S7 is performed as in the first embodiment, and this process is completed.

As described above, in the present embodiment, even when it is difficult to adjust to an appropriate radiation pattern only by adjusting the power supply to the antenna 14, the influence of the interference wave is reduced by instructing the movement of the transceiver 2. It is possible to suppress the deterioration of the communication quality of the wireless communication system 100. Also in this embodiment, when the antenna 14 is movable and the beam steering by the antenna control unit 107 is not possible, the antenna 14 is moved or rotated in place of or in addition to the movement instruction to the transceiver 2. You may.

The above is the description of the embodiment of the present invention, but the present invention is not limited to the configuration of the above-described embodiment, and various modifications or combinations are possible within the scope of the technical idea. .. FIG. 9 is a diagram illustrating the interference suppression process according to the first modification. As shown in FIG. 9, in the interference suppression process, both the attitude control of the mobile terminal 1 in the second embodiment and the movement instruction of the transceiver 2 according to the third embodiment may be performed.

Further, the wireless communication system 100 is not limited to the one used for inspecting infrastructure equipment, and can be used for various purposes. The mobile terminal 1 can be provided with a device according to the application in place of the inspection device 13. Further, the mobile terminal 1 is not limited to the drone, and may be a robot capable of autonomous movement or another wireless communication device having no mobile function.

Further, the mobile terminal 1 may perform other processing for suppressing the interference wave in addition to the interference wave suppression processing described in the first to third embodiments. For example, if it is known in advance from visual inspection or map information that another wireless communication system 200 exists in the vicinity of the inspection area and may cause interference, the mobile terminal 1 is set not to perform communication in that area. May be. Alternatively, if the interference source is a fixed station or the like and the range of influence can be predicted or measured, the result may be mapped and the movement route or communication point of the mobile terminal 1 may be determined in advance from the map information.

1 mobile terminal, 2 transmitter / receiver, 10 control device, 11 drive device, 12 sensor group, 13 inspection device, 14 antenna, 100 wireless communication system, 101 attitude control unit, 102 wireless control unit, 103 RF transmission circuit, 104 RF reception Circuit, 105 interference wave detection unit, 106 interference wave information acquisition unit, 107 antenna control unit, 200 wireless communication system, 201 ETC toll booth, 202 wireless LAN, 210 interference wave.

Claims (10)

It ’s a wireless communication device.
Antennas that transmit and receive radio waves,
An interference wave detection unit that detects the presence or absence of interference waves based on the radio waves received by the antenna, and
When the interference wave is detected by the interference wave detection unit, the interference wave information acquisition unit that acquires the level and the arrival direction of the interference wave, and the interference wave information acquisition unit.
An antenna control unit that performs null steering to direct the null point of the antenna in the arrival direction when the level of the interference wave is equal to or higher than the first threshold value.
Equipped with
When the level of the interference wave is equal to or higher than the first threshold value and the null steering cannot be performed by the antenna control unit, the radio that changes the posture of the wireless communication device or moves or rotates the antenna. Communication device. Antennas that transmit and receive radio waves from transceivers,
An interference wave detection unit that detects the presence or absence of interference waves based on the radio waves received by the antenna, and
When the interference wave is detected by the interference wave detection unit, the interference wave information acquisition unit that acquires the level and the arrival direction of the interference wave, and the interference wave information acquisition unit.
When the level of the interference wave is equal to or higher than the first threshold value, an antenna control unit that performs null steering for directing the null point of the antenna in the arrival direction and beam steering for directing the main beam of the antenna toward the transceiver.
A wireless communication device equipped with . Antennas that transmit and receive radio waves,
An interference wave detection unit that detects the presence or absence of interference waves based on the radio waves received by the antenna, and
When the interference wave is detected by the interference wave detection unit, the interference wave information acquisition unit that acquires the level and the arrival direction of the interference wave, and the interference wave information acquisition unit.
An antenna control unit that performs null steering to direct the null point of the antenna in the arrival direction when the level of the interference wave is equal to or higher than the first threshold value.
Equipped with
The antenna control unit is a wireless communication device that stops transmission of radio waves from the antenna when the level of the interference wave is equal to or higher than a second threshold value larger than the first threshold value. Wireless control for transmitting a signal instructing the movement of the transceiver to the transceiver when the level of the interference wave is equal to or higher than the first threshold value and the beam steering cannot be performed by the antenna control unit. The wireless communication device according to claim 2 , further comprising a unit. The antenna is movable and
The wireless communication device according to claim 2 or 4 , wherein when the level of the interference wave is equal to or higher than the first threshold value and the beam steering cannot be performed by the antenna control unit, the antenna is moved or rotated. The wireless communication device according to any one of claims 1 to 5 .
A wireless communication system including a transceiver capable of communicating with the wireless communication device. It is a wireless communication method in a wireless communication device.
Steps to detect the presence or absence of interference waves based on the radio waves received by the antenna,
When the interference wave is detected, the step of acquiring the level and the direction of arrival of the interference wave, and
When the level of the interference wave is equal to or higher than the first threshold value, a step of performing null steering for directing the null point of the antenna in the arrival direction, and a step of performing null steering.
When the level of the interference wave is equal to or higher than the first threshold value and the null steering cannot be performed, the step of changing the posture of the wireless communication device or moving or rotating the antenna.
Wireless communication method with. The step that the antenna detects the presence or absence of interference waves based on the radio waves received from the transceiver,
When the interference wave is detected, the step of acquiring the level and the direction of arrival of the interference wave, and
When the level of the interference wave is equal to or higher than the first threshold value, a null steering for directing the null point of the antenna in the arrival direction and a beam steering for directing the main beam of the antenna toward the transceiver are performed.
Wireless communication method with. Steps to detect the presence or absence of interference waves based on the radio waves received by the antenna,
When the interference wave is detected, the step of acquiring the level and the direction of arrival of the interference wave, and
When the level of the interference wave is equal to or higher than the first threshold value, a step of performing null steering to direct the null point of the antenna in the arrival direction and a step of performing null steering.
A step of stopping the transmission of radio waves from the antenna when the level of the interference wave is equal to or higher than the second threshold value larger than the first threshold value.
Wireless communication method with. A wireless communication program that causes a processor of a wireless communication device to execute the wireless communication method according to any one of claims 7 to 9 .

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