Controller, imaging system, and method for control of controller

Abstract

To prevent mixture of noise due to radio transmission of an imaging device while the imaging device is imaging.SOLUTION: A controller has a radio communication unit for wirelessly sending control data showing a period of time when the imaging device is imaging to the imaging device. The radio communication device wirelessly sends a radio signal to the imaging device so that sending is not allowed in a manner that the imaging device detects reception of a radio signal by a carrier sense while the imaging device is imaging.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a control device, an imaging system, and a control method for the control device. [Background technology]

[0002] In recent years, imaging technologies that visualize the inside of objects and situations that cannot be seen with the naked eye have been advancing in various fields. Representative examples include sonar using ultrasound, X-ray using X-ray, and radar using radio waves. These convert sound waves or electromagnetic waves into electrical signals using sensing elements, and images are generated from the electrical signals obtained. Currently, electrical signals obtained by sensing elements are almost always digitized using analog-to-digital converters (A / D converters). Once digitized, data can be stored, transmitted, converted, and processed at high speed without worrying about data degradation.

[0003] On the other hand, if noise is mixed into the signals obtained by the sensing elements used for imaging before they are digitized, it will directly lead to distortion of the generated image, so it is necessary to avoid this as much as possible.

[0004] In the field of imaging, there are also increasing cases of transmitting digitized data wirelessly. By replacing wired connections with wireless, the freedom to position imaging devices is increased, and data can be transmitted at high speed to other devices with high processing power to generate images through digital processing. This has the advantage of allowing images to be viewed almost in real time even from a distance.

[0005] However, wireless communication signals are essentially noise for the signals obtained by the sensing elements, and must not affect analog signals, particularly before they are digitized.

[0006] Patent Document 1 discloses a wireless communication device that controls wireless communication according to the CSMA system based on a TDMA timing signal for performing wireless communication according to the TDMA system. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2008-252557 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, since Patent Document 1 does not aim to suppress the inclusion of noise, it does not take noise into consideration.

[0009] An object of the present disclosure is to make it possible to prevent noise from being mixed in due to wireless transmission from an imaging device while the imaging device is capturing images. [Means for solving the problem]

[0010] The control device has a wireless communication unit that wirelessly transmits control data indicating a period during which the imaging device is performing imaging to the imaging device, and the wireless communication unit wirelessly transmits a wireless signal to the imaging device so that transmission is disabled when the imaging device detects reception of a wireless signal by carrier sense during the period during which the imaging device is performing imaging. Effect of the Invention

[0011] According to the present disclosure, it is possible to prevent noise from being mixed in due to wireless transmission from the imaging device while the imaging device is capturing an image. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of an imaging system. [Diagram 2] FIG. 1 is a diagram illustrating an example of the configuration of an imaging system. [Diagram 3] 4 is a timing chart showing a control method of the imaging system. [Figure 4]4 is a flowchart illustrating a control method of the imaging system. [Diagram 5] FIG. 1 is a diagram illustrating an example of the configuration of an imaging system. [Figure 6] 4 is a flowchart illustrating a control method of the imaging system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] (First embodiment) 1 is a diagram showing an example of the configuration of an imaging system 100. The imaging system 100 is an imaging system using wireless communication, and includes a control device 110, an antenna 111, an imaging device 210, and an antenna 211.

[0014] The image capturing device 210 generates image capturing data. The control device 110 controls the image capturing timing of the image capturing device 210 for capturing the image capturing data.

[0015] The control device 110 includes a wireless LAN unit 112, a control data generation unit 113, and an image generation unit 114. The antenna 111 is used for wireless communication of the control device 110. The wireless LAN unit 112 uses the antenna 111 to perform wireless communication.

[0016] The control data generating unit 113 generates control data indicating imaging timing at which the imaging device 210 generates imaging data. The wireless LAN unit 112 wirelessly transmits the control data generated by the control data generating unit 113 to the imaging device 210 via the antenna 111.

[0017] The imaging device 210 wirelessly receives the control data via the antenna 211 , generates imaging data at an imaging timing based on the control data, and wirelessly transmits the generated imaging data to the control device 110 via the antenna 211 .

[0018] The wireless LAN unit 112 wirelessly receives imaging data from the imaging device 210 via the antenna 111. The image generation unit 114 generates a digital image based on the imaging data wirelessly received by the wireless LAN unit 112.

[0019] The imaging device 210 has a wireless LAN unit 212, a control unit 213, a sensing element 214, and an A / D conversion unit 215. The antenna 211 is used for wireless communication of the imaging device 210. The wireless LAN unit 212 uses the antenna 211 to perform wireless communication.

[0020] The wireless LAN unit 212 wirelessly receives control data from the control device 110 via the antenna 211 .

[0021] The control unit 213 controls the imaging of the sensing element 214 at the imaging timing of the control data wirelessly received by the wireless LAN unit 212 , and controls the A / D conversion unit 215 .

[0022] The sensing element 214, under the control of the control unit 213, converts signals to be imaged, such as sound waves or electromagnetic waves, into analog electrical signals to generate image signals.

[0023] The A / D conversion unit 215 is an analog / digital conversion unit that converts the analog imaging signal generated by the sensing element 214 into digital imaging data.

[0024] The wireless LAN unit 212 wirelessly transmits the imaging data converted by the A / D conversion unit 215 to the control device 110 via the antenna 211.

[0025] As described above, it is necessary to prevent noise from being mixed into the analog imaging signal generated by the sensing element 214 before it is converted into digital imaging data by the A / D conversion unit 215 as much as possible.

[0026] However, the radio waves used by the wireless LAN unit 212 are noise for analog image signals. In particular, the radio waves radiated from the antenna 211 during transmission by the wireless LAN unit 212 may become noise of a magnitude that cannot be ignored because the distance between the antenna 211 and the sensing element 214 is short.

[0027] On the other hand, the influence of noise due to radio waves radiated from the antenna 111 during reception by the wireless LAN unit 212 is almost negligible because a large distance is maintained between the antenna 111 and the sensing element 214. The strength of the signal reaching the sensing element 214 from the antenna 111 is sufficiently small and has almost no effect on the analog imaging signal of the sensing element 214. A first embodiment for suppressing the intrusion of noise will be described below.

[0028] 2 is a diagram showing an example of the configuration of an imaging system 150 according to the first embodiment. The imaging system 150 includes a control device 120, an antenna 121, an antenna 125, an imaging device 220, and an antenna 221. The imaging system 150 is obtained by adding an antenna 125 and a wireless LAN signal generation unit 126 to the imaging system 100 in FIG.

[0029] The control device 120 has a wireless LAN unit 122, a control data generation unit 123, an image generation unit 124, and a wireless LAN signal generation unit 126. The wireless LAN unit 122 is similar to the wireless LAN unit 112 in Fig. 1. The control data generation unit 123 is similar to the control data generation unit 113 in Fig. 1. The image generation unit 124 is similar to the image generation unit 114 in Fig. 1. The antenna 121 is similar to the antenna 111 in Fig. 1.

[0030] The imaging device 220 has a wireless LAN unit 222, a control unit 223, a sensing element 224, and an A / D conversion unit 225. The wireless LAN unit 222 is similar to the wireless LAN unit 212 in FIG. 1. The control unit 223 is similar to the control unit 213 in FIG. 1. The sensing element 224 is similar to the sensing element 214 in FIG. 1. The A / D conversion unit 225 is similar to the A / D conversion unit 215 in FIG. 1. The antenna 221 is similar to the antenna 211 in FIG. 1.

[0031] The wireless LAN used by the control device 120 and the imaging device 220 is, for example, a wireless LAN of the CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) method. In this method, an operation called carrier sense is performed to check whether or not radio waves of a certain power or more are detected in the frequency band to be used during a certain period immediately before transmitting radio waves for communication, and it is determined whether or not radio waves can be transmitted. If radio waves of a certain power or more are detected by carrier sense, the transmission of radio waves is temporarily postponed and the device waits until the next time slot. Radio waves are detected in the same manner in the next time slot, and radio waves are transmitted only if radio waves of a certain power or more are not detected. Carrier sense is a mechanism for avoiding interference between communications in the same frequency band. In this embodiment, the carrier sense is used to suppress noise contamination.

[0032] 3 based on the control data generated by the control data generation unit 123, the wireless LAN signal generation unit 126 generates a wireless LAN signal capable of carrier sense detection by the wireless LAN unit 222 during the imaging timing period of the imaging device 220 in Fig. 3. The antenna 125 radiates the wireless LAN signal generated by the wireless LAN signal generation unit 126 toward the antenna 221 of the imaging device 220. The wireless LAN signal generation unit 126 transmits the wireless LAN signal capable of carrier sense detection to the imaging device 220 via the antenna 125 during the imaging timing period of the imaging device 220.

[0033] The frequency of the wireless LAN signal wirelessly transmitted by the wireless LAN signal generating unit 126 is the same as that used for wireless transmission and reception by the wireless LAN unit 222. The signal strength of the wireless LAN signal wirelessly transmitted by the wireless LAN signal generating unit 126 is set to a signal strength that can be detected by the carrier sense of the wireless LAN unit 222.

[0034] The wireless LAN signal transmitted wirelessly by the wireless LAN signal generating unit 126 is intended to be detected by carrier sense, so the modulation method, data rate, payload, etc. are not important, but it is necessary to ensure that the wireless LAN signal is not interrupted during the transmission period.

[0035] When transmitting, the wireless LAN unit 222 performs carrier sense to check whether radio waves of a certain power or more are detected in the frequency band to be used for a certain period immediately before transmission, and determines whether transmission is permitted. When radio waves of a certain power or more are detected by carrier sense, the wireless LAN unit 222 postpones transmission, waits until the next time slot, and repeats the above carrier sense. Moreover, the wireless LAN unit 222 can transmit only when radio waves of a certain power or more are not detected by carrier sense.

[0036] The wireless LAN signal generating unit 126 transmits a wireless LAN signal to the imaging device 220 via the antenna 125 during the imaging timing period of the imaging device 220. During this period, if the wireless LAN unit 222 performs carrier sense, it detects a certain level of power or more, and therefore transmission is not possible. In other words, the wireless LAN unit 222 cannot perform wireless transmission via the antenna 221 during the imaging timing period of the imaging device 220, and no radio waves are emitted from the antenna 221. As a result, there is no noise mixed in from the antenna 221 to the analog imaging signal of the sensing element 224, and deterioration in the quality of the digital imaging data can be suppressed.

[0037] During the period when the wireless LAN signal is radiated from the antenna 125, the wireless LAN unit 222 is unable to transmit new packets. In other words, since the transmission function of the wireless LAN unit 222 can be stopped during the imaging timing period of the imaging device 220, it becomes possible to stop transmission of the wireless LAN unit 222 only during the period when the sensing element 224 and the A / D conversion unit 225 are generating imaging data.

[0038] FIG. 3 is a timing chart showing an example of an output signal of the sensing element 224, the operation of the A / D conversion unit 225, and the operation of the wireless LAN signal generation unit 126. In FIG.

[0039] The sensing element 224 performs imaging processing during the imaging timing period indicated by the control data generated by the control data generator 123, and outputs an analog imaging signal.

[0040] The A / D conversion unit 225 converts the analog imaging signal output from the sensing element 224 into digital imaging data during the imaging timing period indicated by the control data generated by the control data generation unit 123.

[0041] The sensing element 224 and the A / D conversion unit 225 operate during the imaging timing period. When the A / D conversion unit 225 is not operating, digital sand sculpture data is not generated and the analog signal output by the sensing element 224 is discarded. Therefore, the period during which it is desired to stop transmission from the wireless LAN unit 222 is the imaging timing period.

[0042] What the wireless LAN signal generating unit 126 can control is to prevent the wireless LAN unit 222 from starting a new packet transmission. Even if the wireless LAN signal generating unit 126 transmits a wireless LAN signal while the wireless LAN unit 222 is transmitting, it cannot stop the packet transmission being transmitted by the wireless LAN unit 222. For this reason, the wireless LAN signal generating unit 126 needs to start transmitting the wireless LAN signal at a timing earlier than the time that the wireless LAN unit 222 uses to transmit one packet.

[0043] Here, the time that the wireless LAN unit 222 uses for one packet depends on the data rate of the modulation that the wireless LAN unit 222 uses for transmission. For the most reliable operation, it is sufficient to secure the longest time required to transmit one packet when the slowest data rate is used. However, doing so reduces the proportion of the time that the wireless LAN unit 222 can use for data transmission.

[0044] Therefore, the maximum time that wireless LAN unit 222 uses for one packet may be estimated according to the data rate that wireless LAN unit 222 used immediately before. For example, when MCS9 of IEEE 802.11ac is used for the transmission packets of wireless LAN unit 222, the longest time required for transmitting one packet for a slightly lower data rate such as MCS7 may be used, taking into consideration the possibility of the data rate suddenly dropping. The longest time required for transmitting one packet is the wireless LAN maximum packet length.

[0045] The wireless LAN signal generating unit 126 generates and transmits a wireless LAN signal from the longest time required for transmitting one packet before the start time of the imaging timing period to the end time of the imaging timing period. As a result, the wireless LAN unit 222 cannot perform wireless transmission via the antenna 221 during the imaging timing period of the imaging device 220, and radio waves are not emitted from the antenna 221. As a result, during the imaging timing period of the imaging device 220, noise is not mixed from the antenna 221 into the analog imaging signal of the sensing element 224, and deterioration of the quality of the digital imaging data can be suppressed.

[0046] 4 is a flowchart showing a control method for the image capture system 150 according to the first embodiment. Here, the control device 120 starts in a state in which it is connected to the image capture device 220 via wireless LAN.

[0047] First, in step S101, the control data generating unit 123 of the control device 120 generates control data indicating image capturing timing.

[0048] Next, in step S102, the wireless LAN unit 122 of the control device 120 wirelessly transmits the control data generated by the control data generation unit 123 to the imaging device 220 via the antenna 121. The wireless LAN unit 222 of the imaging device 220 wirelessly receives the control data from the control device 120 via the antenna 221. The control unit 223 does not operate the sensing element 224 and the A / D conversion unit 225 until the imaging timing indicated in the control data wirelessly received by the wireless LAN unit 222 arrives.

[0049] Next, in step S103, the wireless LAN signal generating unit 126 starts wireless transmission of the wireless LAN signal to the imaging device 220 via the antenna 125 a predetermined time before the imaging timing period based on the timing chart shown in Fig. 3. Here, the predetermined time is, for example, a time equal to or longer than the longest time required for the wireless LAN unit 222 to transmit one packet.

[0050] Next, in step S104, the control unit 223 of the imaging device 220 controls the sensing element 224 and the A / D conversion unit 225 to operate during the imaging timing period indicated by the control data wirelessly received by the wireless LAN unit 222. The sensing element 224 generates an analog imaging signal by imaging processing. The A / D conversion unit 225 converts the analog imaging signal generated by the sensing element 224 into digital imaging data. During the imaging timing period, the wireless LAN signal generation unit 126 is wirelessly transmitting a wireless LAN signal, so the wireless LAN unit 222 is unable to transmit wirelessly and no noise is mixed in the analog imaging signal of the sensing element 224 from the antenna 221.

[0051] Next, in step S105, the wireless LAN signal generating unit 126 of the control device 120 ends wireless transmission of the wireless LAN signal to the imaging device 220 via the antenna 125 after the end time of the imaging timing period. After the wireless transmission by the wireless LAN signal generating unit 126 ends, the wireless LAN unit 222 becomes capable of wireless transmission.

[0052] Next, in step S106, the wireless LAN unit 222 of the imaging device 220 wirelessly transmits the digital imaging data converted by the A / D conversion unit 225 to the control device 120 via the antenna 221. The wireless LAN unit 122 of the control device 120 wirelessly receives the digital imaging data from the imaging device 220 via the antenna 121.

[0053] Next, in step S107, the image generating unit 124 of the control device 120 generates a digital image based on the digital imaging data wirelessly received by the wireless LAN unit 122, and visualizes the imaging data.

[0054] As described above, the wireless LAN unit 122 and the wireless LAN signal generating unit 126 are each a wireless communication unit, and perform CSMA / CA wireless communication with the imaging device 220. Note that the wireless LAN signal generating unit 126 may be integrated into the wireless LAN unit 122, and the antenna 125 may be integrated into the antenna 121.

[0055] In step S102, the wireless LAN unit 122 wirelessly transmits to the imaging device 220 control data indicating a period during which the imaging device 220 performs imaging.

[0056] In step S103, the wireless LAN signal generating unit 126 wirelessly transmits a wireless signal to the imaging device 220 so that the imaging device 220 cannot transmit a wireless signal by detecting reception of the wireless signal through carrier sense during a period when the imaging device 220 is capturing an image. The wireless signal is, for example, a wireless LAN signal.

[0057] 3, the wireless LAN signal generation unit 126 wirelessly transmits a wireless signal to the imaging device 220 during a period including a period during which the imaging device 220 captures an image. Furthermore, the wireless LAN signal generation unit 126 starts wirelessly transmitting a wireless signal to the imaging device 220 at least the maximum time used by the imaging device 220 to transmit one packet before the timing at which the imaging device 220 starts capturing an image.

[0058] The time that the wireless LAN unit 222 uses for one packet depends on the data rate of modulation used for transmission by the wireless LAN unit 222. The wireless LAN signal generating unit 126 starts wireless transmission of a wireless signal to the imaging device 220 at least the maximum time that would be used for transmitting one packet if the imaging device 220 used the data rate that was used immediately before, with respect to the timing at which the imaging device 220 starts imaging.

[0059] In step S103, the wireless LAN signal generating unit 126 wirelessly transmits a wireless signal after wirelessly transmitting the control data in step S102.

[0060] In step S104, the imaging device 220 captures images during the period indicated by the control data, and generates imaging data. At this time, the imaging device 220 detects reception of a wireless signal by carrier sense, and is thus disabled from transmitting.

[0061] In step S105, the wireless LAN signal generating unit 126 ends the wireless transmission of the wireless signal to the imaging device 220.

[0062] In step S106, the wireless LAN unit 122 wirelessly receives imaging data generated by imaging device 220 after wireless transmission of the wireless signal in step S105 has ended.

[0063] In step S107, the image generating unit 124 generates a digital image based on the above-mentioned imaging data.

[0064] As described above, according to this embodiment, the wireless LAN signal generation unit 126 wirelessly transmits a wireless signal during the period when the imaging device 220 is capturing an image. Then, during the period when the imaging device 220 is capturing an image, the imaging device 220 detects wireless reception of a wireless signal by carrier sense and is unable to transmit. This makes it possible to prevent noise from being mixed into the analog imaging signal of the sensing element 224 due to radio waves radiated from the antenna 221.

[0065] It is possible to prevent noise due to wireless communication from being mixed into the analog imaging signal obtained by the sensing element 224 during the period in which the imaging signal obtained by the sensing element 224 is captured by the A / D conversion unit 225. Furthermore, since the imaging device 220 including the sensing element 224 and the wireless LAN unit 222 does not need to be provided with a special mechanism to achieve the object of this embodiment, it can be easily realized.

[0066] Second embodiment In the second embodiment, a function for adjusting the strength of the wireless LAN signal output by the wireless LAN signal generating unit 136 in Fig. 5 is added to the first embodiment. The strength of the wireless LAN signal output by the wireless LAN signal generating unit 136 may be greater than the threshold detected by the wireless LAN unit 232 in Fig. 5 through carrier sense. If the strength of the wireless LAN signal output by the wireless LAN signal generating unit 136 is stronger than necessary, it will waste power, the range of radio waves will become wider, and there will be a high possibility of affecting other devices, so this should be avoided. An imaging system according to the second embodiment will be described below.

[0067] 5 is a diagram showing an example of the configuration of an imaging system 160 according to the second embodiment. The imaging system 160 is obtained by adding a ping operation detection unit 137, a signal intensity control unit 138, and a variable amplification unit 139 to the imaging system 150 in FIG.

[0068] The imaging system 160 includes a control device 130 , an antenna 131 , an antenna 135 , an imaging device 230 , and an antenna 231 .

[0069] The imaging device 230 has a wireless LAN unit 232, a control unit 233, a sensing element 234, and an A / D conversion unit 235. The wireless LAN unit 232 is similar to the wireless LAN unit 222 in FIG. 2. The control unit 233 is similar to the control unit 223 in FIG. 2. The sensing element 234 is similar to the sensing element 224 in FIG. 2. The A / D conversion unit 235 is similar to the A / D conversion unit 225 in FIG. 2. The antenna 231 is similar to the antenna 221 in FIG. 2.

[0070] The control device 130 has a wireless LAN unit 132, a control data generation unit 133, an image generation unit 134, a wireless LAN signal generation unit 136, a signal intensity control unit 138, and a variable amplification unit 139. The wireless LAN unit 132 is obtained by adding a ping operation detection unit 137 to the wireless LAN unit 122 in FIG. 2. The control data generation unit 133 is similar to the control data generation unit 123 in FIG. 2. The image generation unit 134 is similar to the image generation unit 124 in FIG. 2. The wireless LAN signal generation unit 136 is similar to the wireless LAN signal generation unit 126 in FIG. 2. The antenna 131 is similar to the antenna 121 in FIG. 2. The antenna 135 is similar to the antenna 125 in FIG. 2.

[0071] The wireless LAN unit 132 newly includes a ping operation detection unit 137. Here, ping is an abbreviation of Packet INternet Groper (grope means "to feel around"), and is a command for checking whether communication (continuity) is possible with a destination host in a TCP / IP network.

[0072] By using the ping command, the ping operation detection section 137 can check whether or not transmission from the wireless LAN section 232 is suppressed while the wireless LAN signal generation section 136 is operating.

[0073] The signal intensity control unit 138 controls the gain of the variable amplifier unit 139 based on the execution result of the ping command detected by the ping operation detection unit 137, and determines the gain of the variable amplifier unit 139 during the imaging timing period.

[0074] The variable amplifier 139 amplifies the wireless LAN signal generated by the wireless LAN signal generator 136 with a gain determined by the signal intensity controller 138, and supplies the amplified wireless LAN signal to the antenna 135. The variable amplifier 139 wirelessly transmits the amplified wireless LAN signal to the imaging device 230 via the antenna 125.

[0075] 6 is a flowchart showing a method for controlling the gain of variable amplifier 139, and shows a method for appropriately adjusting the strength of the signal radiated from antenna 135. The processing in FIG. 6 is performed before the processing in FIG.

[0076] First, in step S201, the wireless LAN unit 132 of the control device 130 and the wireless LAN unit 232 of the imaging device 230 establish a wireless LAN communication connection with each other via the antennas 131 and 231.

[0077] Next, in step S202, after the above-mentioned connection is completed, the ping operation detection unit 137 of the control device 130 transmits a ping command to the imaging device 230 via the antenna 131 and continuously detects whether a response has been received from the imaging device 230. When the reception of a response to the ping command is detected, the process proceeds to step S203.

[0078] In step S203, the wireless LAN signal generating unit 136 of the control device 130 starts generating a wireless LAN signal, and the variable amplifier 139 wirelessly transmits the generated wireless LAN signal at low output to the imaging device 230 via the antenna 135. At this time, the gain of the variable amplifier 139 determined by the signal intensity control unit 138 is a sufficiently small value, and the intensity of the wireless LAN signal wirelessly received by the wireless LAN unit 232 does not exceed a threshold detected by carrier sense in the wireless LAN unit 232. If carrier sense in the wireless LAN unit 232 is not detected, the wireless LAN unit 232 does not stop transmitting a response to the ping command, and the ping operation detection unit 137 detects reception of the response.

[0079] In step S204, the ping operation detection unit 137 determines whether or not reception of a response to the ping command from the wireless LAN unit 232 has stopped. If reception has not stopped (NO in S204), the process proceeds to step S205.

[0080] In step S205, the signal intensity control unit 138 controls the gain of the variable amplifier unit 139 to be large, thereby increasing the intensity of the wireless LAN signal radiated from the antenna 131. After that, the process returns to step S204.

[0081] In step S204, the ping operation detection unit 137 again determines whether or not reception of the response to the ping command from the wireless LAN unit 232 has stopped. After repeating the above steps S204 and S205, the wireless LAN unit 232 eventually receives a wireless LAN signal with a power level exceeding the threshold by carrier sense, and stops transmitting the response to the ping command.

[0082] In step S204, if ping operation detection unit 137 determines that reception of the response to the ping command from wireless LAN unit 232 has stopped (YES in S204), the process proceeds to step S206. The fact that reception of the response to the ping command has stopped indicates that the wireless LAN signal amplified by variable amplifier 139 has exceeded a threshold detected by carrier sense in wireless LAN unit 232, and transmission from wireless LAN unit 232 has been suppressed. In other words, the gain of variable amplifier 139 controlled by signal intensity control unit 138 at this point in time is the minimum necessary gain. Since the minimum necessary gain has been determined, the process proceeds to step S206.

[0083] In step S206, the wireless LAN signal generating unit 136 and the variable amplifier 139 stop operating, and the wireless transmission of the wireless LAN signal via the antenna 135 ends.

[0084] Next, in step S207, the signal intensity control unit 138 determines the gain of the variable amplifier 139 to be used during imaging based on the minimum necessary gain described above, taking into consideration fluctuations in the wireless communication environment, and adding an appropriate margin to the minimum necessary gain. Thereafter, the control device 130 uses the determined gain of the variable amplifier 139 to perform the same operation as in the first embodiment (FIG. 4).

[0085] As described above, the variable amplifier 139 amplifies the wireless LAN signal that the wireless LAN signal generator 136 wirelessly transmits.

[0086] In step S204, the ping operation detection unit 137 determines whether or not a response to the transmission of a ping command to the imaging device 230 has been received while the variable amplifier unit 139 is amplifying the Wireless LAN signal with different gains and wirelessly transmitting it.

[0087] In step S207, the signal intensity control unit 138 functions as a determination unit, and determines the gain of the variable amplifier unit 139 when disabling transmission from the imaging device 230, according to the result of the above determination.

[0088] As described above, according to this embodiment, the signal intensity control unit 138 determines the gain of the variable amplifier unit 139 to be used during imaging based on the minimum necessary gain. This makes it possible to suppress power waste and reduce the possibility of affecting other devices.

[0089] (Other embodiments) The present disclosure can also be realized by a process in which a program for implementing one or more functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) for implementing one or more functions.

[0090] It should be noted that the above-described embodiments are merely illustrative of specific examples of implementing the present disclosure, and the technical scope of the present disclosure should not be interpreted as being limited by these embodiments. In other words, the present disclosure can be implemented in various forms without departing from its technical concept or main features.

[0091] The disclosure of this embodiment includes the following configurations and methods. (Configuration 1) a wireless communication unit that wirelessly transmits control data indicating a period during which the imaging device performs imaging to the imaging device; A control device characterized in that the wireless communication unit wirelessly transmits a wireless signal to the imaging device so that transmission is disabled when the imaging device detects reception of a wireless signal by carrier sense during a period when the imaging device is performing imaging. (Configuration 2) The wireless communication unit includes: a first wireless communication unit that wirelessly transmits control data indicating a period during which the imaging device performs imaging to the imaging device; a second wireless communication unit that wirelessly transmits a wireless signal to the imaging device so that transmission is disabled when the imaging device detects reception of the wireless signal by carrier sense during a period in which the imaging device captures an image; 2. The control device according to claim 1, further comprising: (Configuration 3) 3. The control device according to claim 1, wherein the wireless communication unit performs wireless communication with the imaging device in accordance with CSMA / CA. (Configuration 4) 4. The control device according to any one of configurations 1 to 3, wherein the wireless communication unit wirelessly transmits the wireless signal to the imaging device during a period that includes a period during which the imaging device performs imaging. (Configuration 5) The control device according to any one of configurations 1 to 4, wherein the wireless communication unit starts wireless transmission of the wireless signal to the imaging device at least a maximum time used by the imaging device for transmitting one packet before the timing at which the imaging device starts imaging. (Configuration 6) The control device according to configuration 5, wherein the wireless communication unit starts wireless transmission of the wireless signal to the imaging device at least a maximum time used for transmitting one packet when the imaging device uses a data rate used immediately before the imaging device starts imaging. (Configuration 7) 3. The control device according to configuration 2, further comprising an amplifier section for amplifying a wireless signal wirelessly transmitted by the second wireless communication section. (Configuration 8) the first wireless communication unit determines whether or not a response to transmission of a command to the imaging device has been received while the amplifier unit is amplifying the wireless signal with different gains and wirelessly transmitting the amplified wireless signal; 8. The control device according to configuration 7, further comprising a decision unit that decides a gain of the amplifier unit when disabling transmission of the imaging device according to a result of the judgment. (Configuration 9) 9. The control device according to any one of configurations 1 to 8, wherein the wireless communication unit wirelessly transmits the wireless signal after wirelessly transmitting the control data. (Configuration 10) 10. The control device according to any one of configurations 1 to 9, wherein the wireless communication unit wirelessly receives imaging data generated by imaging of the imaging device after wireless transmission of the wireless signal is completed. (Configuration 11) 11. The control device according to configuration 10, further comprising an image generating unit that generates an image based on the imaging data. (Configuration 12) A control device according to any one of configurations 1 to 11, an imaging device that performs imaging during a period indicated by the control data; The imaging system according to the present invention is characterized in that the imaging device is disabled from transmitting when it detects reception of the wireless signal by carrier sense. (Method 1) wirelessly transmitting control data indicating a period during which the imaging device performs imaging to the imaging device; transmitting a wireless signal to the imaging device so that the imaging device is disabled from transmitting a wireless signal by detecting reception of the wireless signal through carrier sense during a period when the imaging device is performing imaging; A control method for a control device comprising the steps of: [Explanation of symbols]

[0092] 110, 120, 130: control device, 111, 121, 131: antenna, 112, 122, 132: wireless LAN unit, 113, 123, 133: control data generation unit, 114, 124, 134: image generation unit, 125, 135: antenna, 126, 136: wireless LAN signal generation unit, 137: ping operation detection unit, 138: signal strength control unit, 139: variable amplification unit, 210, 220, 230: imaging device, 211, 221, 231: antenna, 212, 222, 232: wireless LAN unit, 213, 223, 233: control unit, 214, 224, 234: sensing element, 215, 225, 235: A / D conversion unit

Claims

1. a wireless communication unit that wirelessly transmits control data indicating a period during which the imaging device performs imaging to the imaging device; A control device characterized in that the wireless communication unit wirelessly transmits a wireless signal to the imaging device so that transmission is disabled when the imaging device detects reception of a wireless signal by carrier sense during a period when the imaging device is performing imaging.

2. The wireless communication unit includes: a first wireless communication unit that wirelessly transmits control data indicating a period during which the imaging device performs imaging to the imaging device; a second wireless communication unit that wirelessly transmits a wireless signal to the imaging device so that transmission is disabled when the imaging device detects reception of the wireless signal by carrier sense during a period in which the imaging device captures an image; 2. The control device according to claim 1, further comprising:

3. The control device according to claim 1 , wherein the wireless communication unit performs wireless communication with the imaging device in accordance with a CSMA / CA system.

4. The control device according to claim 1 , wherein the wireless communication unit wirelessly transmits the wireless signal to the imaging device during a period that includes a period during which the imaging device performs imaging.

5. The control device according to claim 1, characterized in that the wireless communication unit starts wireless transmission of the wireless signal to the imaging device at least a maximum time used by the imaging device for transmitting one packet before the timing at which the imaging device starts imaging.

6. The control device according to claim 5, characterized in that the wireless communication unit starts wireless transmission of the wireless signal to the imaging device at least a maximum time used for transmitting one packet when the imaging device uses the data rate used immediately before the imaging device starts imaging.

7. 3. The control device according to claim 2, further comprising an amplifier section for amplifying the wireless signal wirelessly transmitted by the second wireless communication section.

8. the first wireless communication unit determines whether or not a response to a command transmitted to the imaging device has been received while the amplifier unit is amplifying the wireless signal with different gains and wirelessly transmitting the amplified wireless signal; 8. The control device according to claim 7, further comprising a determination unit that determines a gain of the amplifier unit when disabling transmission of the imaging device in accordance with a result of the determination.

9. The control device according to claim 1 , wherein the wireless communication unit wirelessly transmits the wireless signal after wirelessly transmitting the control data.

10. The control device according to claim 1 , wherein the wireless communication unit wirelessly receives imaging data generated by imaging with the imaging device after wireless transmission of the wireless signal is completed.

11. The control device according to claim 10 , further comprising an image generating unit that generates an image based on the imaging data.

12. A control device according to any one of claims 1 to 11, an imaging device that performs imaging during a period indicated by the control data; The imaging system according to the present invention is characterized in that the imaging device is disabled from transmitting the radio signal by detecting reception of the radio signal through carrier sense.

13. wirelessly transmitting control data indicating a period during which the imaging device performs imaging to the imaging device; transmitting a wireless signal to the imaging device so that the imaging device is disabled from transmitting a wireless signal by detecting reception of the wireless signal through carrier sense during a period when the imaging device is performing imaging; A control method for a control device comprising the steps of:

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