WO2018016642A1 - Transmitter, receiver, and program - Google Patents

Abstract

This transmitter is provided with: a transmission control unit that controls the transmission of information in accordance with the number of retransmissions based on a frame time and a gap time of a rolling shutter-type imaging device, a per packet transmission time of information that comprises multiple packets and is transmitted to the imaging device, and the number of packets constituting the information; and a light-emitting unit that transmits information by emitting light in an emission pattern based on transmission control performed by the transmission control unit.

Description

Transmitting apparatus, receiving apparatus, and program

The present invention relates to a transmission device, a reception device, and a program.
This application is based on US Patent Application No. 62 / 365,390 filed provisionally in the United States on July 22, 2016 and Japanese Patent Application No. 2017-42218 filed in Japan on March 6, 2017. Claim priority and incorporate the contents here.

Conventionally, a system for exchanging information by wireless communication between a plurality of devices is known.

Japanese Unexamined Patent Publication No. 2016-129007

Conventionally, when information acquired by a sensor is transmitted to another device by wireless communication, it is necessary to set communication between devices in advance. This communication setting was troublesome.
An object of the present invention is to provide a transmission device, a reception device, and a program that saves the trouble of setting communication.

One embodiment of the present invention includes a frame time and a gap time of an imaging device using a rolling shutter method, a transmission time per packet of information that is configured by a plurality of packets and is transmitted to the imaging device, and a packet that configures the information A transmission control unit that performs transmission control of the information according to the number of retransmissions based on the number of packets of the transmission, and a light emitting unit that transmits the information by emitting light with a light emission pattern based on transmission control by the transmission control unit Device.

In another aspect of the present invention, the number of retransmissions is such that the number of packets is equal to or greater than a ratio of a product of the number of retransmissions and the transmission time and a sum of the gap time and the transmission time. And the frame time is less than or equal to the frame time.

According to another aspect of the present invention, the light emitting unit includes three or more light emitting elements, and at least one of the other light emitting elements is disposed on an arrangement axis on which at least two of the light emitting elements are disposed. It is a transmitter that has not been performed.

According to another aspect of the present invention, the packet includes identification information indicating whether the packet is a leading packet or a subordinate packet, and the information amount of the identification information indicating the subordinate packet among the identification information includes a leading packet. This is a transmission device that is smaller than the information amount of the identification information indicating.

One embodiment of the present invention is a transmission device that includes a light receiving sensor that receives light, and starts transmitting information based on a blinking pattern of light captured by the light receiving sensor.

According to another aspect of the present invention, a frame time and a gap time of an imaging apparatus based on a rolling shutter method, a transmission time per packet of the information configured by a plurality of packets and transmitted to the imaging apparatus, and the information A transmission control unit that performs transmission control of the information based on the number of retransmissions based on the number of packets that constitutes the light emitting unit, and a light emitting unit that transmits the information by emitting light by a light emission pattern based on transmission control by the transmission control unit And a start / stop unit that starts or stops at least one of the transmission control unit, the light emitting unit, and the light receiving sensor based on a predetermined condition.

According to another aspect of the present invention, the predetermined condition is a time based on a blinking interval of light received by the light receiving sensor, and the start / stop unit permits the light emission based on the predetermined condition. The light emission permission unit is configured to start and stop the light emission based on a determination result of whether or not the light receiving sensor receives light during a period in which the activation stop unit activates the light emission permission unit. This is a transmission device that permits light emission of the unit.

According to another aspect of the present invention, the predetermined condition is a time based on a blinking interval of light received by the light receiving sensor, and the start / stop unit permits the light emission based on the predetermined condition. The light emission permission unit is configured to start and stop the light emission based on a determination result of whether or not the light receiving sensor receives light during a period in which the activation stop unit activates the light emission permission unit. This is a transmission device that permits light emission of the unit.

According to another embodiment of the present invention, a transmission control unit that performs transmission control of information, a light emitting unit that transmits the information by emitting light with a light emission pattern based on transmission control by the transmission control unit, and light reception A light reception sensor, a reception state determination unit that determines a reception state of the information based on a light reception state of the light reception sensor, and a determination result determined by the reception state determination unit; And a retransmission control unit that retransmits information.

According to another aspect of the present invention, the information is transmitted for each segment composed of a plurality of packets, and the time taken to transmit the segment is the reception delay time of the segment of the imaging device and the imaging device. A time longer than the time required for switching between the light emitting state in which the light is emitted and the non-light emitting state in which the light is not emitted. The transmission apparatus retransmits the previously transmitted segment as the information.

One embodiment of the present invention includes a transmission control unit that performs transmission control of information, and a light-emitting unit that transmits the information by emitting light according to a light emission pattern based on transmission control by the transmission control unit. The control unit is a transmission device that emits a light emission pattern indicating that the transmission of the information is completed when the transmission of the information is completed.

According to another aspect of the present invention, the transmission control unit includes the frame information and the gap time of the imaging device based on a rolling shutter method, and a plurality of packets that are transmitted to the imaging device. It is a transmission apparatus which transmits by the number of retransmissions based on the transmission time per packet and the number of packets of the packets constituting the information.

Further, according to one aspect of the present invention, an imaging unit using a rolling shutter system, a frame time and a gap time of the imaging unit, a transmission time per packet of information configured by a plurality of packets, and the information are configured. A light-emitting unit that transmits the information by a light-emission pattern based on the number of retransmissions based on the number of packets of the packet includes a decoding unit that decodes the information based on a light-emission pattern image captured by the imaging unit.

Another aspect of the present invention is a receiving device further comprising: a light emitting unit that emits light; and a light emission control unit that causes the light emitting unit to emit a light emission pattern according to a reception state of the information of the device itself. .

In another aspect of the present invention, the decoding unit is a receiving device that decodes the information by acquiring a temporal change of a light emission pattern indicated by the light emission pattern image by using a plurality of scanning rows.

Further, according to one embodiment of the present invention, a frame time and a gap time of an imaging unit using a rolling shutter method, a transmission time per packet of information configured by a plurality of packets, and a packet of the information configuring the information Based on the light emission pattern image acquired in the acquisition step, the light emission unit transmitting the information by the light emission pattern based on the number of retransmissions based on the number of packets acquires the light emission pattern image captured by the imaging unit And a decoding step for decoding the information.

According to the present invention, it is possible to provide a transmission device, a reception device, and a program that saves the trouble of setting communication.

It is a figure which shows an example of the communication using a rolling shutter phenomenon. It is a figure which shows an example of a packet loss. It is a figure which shows an example of a packet repetition communication system. It is a figure which shows an example of a structure of the packet made into sequenceless. It is a figure which shows an example of the communication range expansion method. It is a figure which shows an example of the transmission apparatus concerning 1st Embodiment, and the IoT device which communicates by radio | wireless. It is a figure which shows the method of speeding up communication speed. It is a figure which shows an example of the evaluation result of the transmitter of 1st Embodiment, and a receiver. 4 is a flowchart illustrating an example of an operation of the transmission apparatus according to the first embodiment. It is a figure which shows an example of the external appearance structure of the transmitter which concerns on 2nd Embodiment, and a receiver. It is a figure which shows an example of a structure of a transmitter and a receiver. It is a flowchart which shows an example of operation | movement of a transmitter. It is a figure which shows an example of operation | movement of a transmission determination part. It is a figure which shows an example of operation | movement of the starting stop part by which stop time is controlled. It is a figure which shows an example of a structure of the transmitter which concerns on 3rd Embodiment. It is a flowchart which shows an example of operation | movement of a transmitter. It is a figure which shows an example of the bidirectional | two-way communication with a transmitter and a receiver. It is a figure which shows an example of the 2nd bidirectional | two-way communication with a transmitter and a receiver.

[First Embodiment]
Hereinafter, with reference to the drawings, a description will be given of a packet repetitive transmission method for dealing with an interframe loss in LED (light emitting diode) -camera communication according to the present invention. The LED is an example of a light emitting unit.

[Summary]
The authors are researching LED-camera communication for smartphones as a means of acquiring internal information for devices that do not have a display. This communication, in which information is obtained by holding a smartphone camera over an LED, is a “one-to-one” method that provides low-cost and space-saving by providing a communication function to the LED originally attached to the device. Excellent “intuition” for communication. In the LED-camera communication that reads out multi-bit information from each shooting frame using the rolling shutter phenomenon, bursty packet loss occurs due to the non-imaging time that exists between frames called gap time. Is a problem. In addition, since the length of the gap time varies depending on the model of the smartphone, a countermeasure that does not depend on the model is required. In this paper, we show that communication without data loss can be realized by packet repetitive transmission focusing on the burstiness of packet loss, and that it is possible to support multiple models with the same setting of parameter settings such as the number of repetitive transmissions.

[keyword]
LED-camera communication for smartphones, rolling shutter phenomenon, visible light communication

[Communication between IoT device and smartphone]
・ Communication using wireless-NFC: Difficult to downsize due to antenna size-BLE and Wi-Fi: Lack of intuition-Communication between LED and camera-Only the LED needs to be on the mono side, downsizing Easy to reduce costs-Intuition to hold your smartphone over visible light

[Use case of LED-camera communication]
-IoT device construction-A small LED and sensor data visualization function can be implemented at a cost of about 100 yen-High functionality LED attached to home appliances-Not only simple internal information such as ON / OFF, but also error information and Sending detailed internal information such as response procedures using LEDs

[Communication using the rolling shutter phenomenon]
・ Smartphone captures 30 frames (images) per second Rolling shutter phenomenon ・ Pixels in the frame are exposed for each pixel row ・ LED blinking information is reflected in the stripe pattern in the frame ・ High speed without a dedicated photodiode Communication is possible

[Problem: Burst-like packet loss due to gap between frames]
・ Burst-like packet loss occurs due to incapable imaging time (gap time) between frames ・ Communication between smartphone and LED control microcomputer is only unidirectional, so information is transmitted from LED only within frame time Impossible to do

[Repeated packet transmission method]
Repeated transmission S times for each block composed of N packets TF: Frame time, TG: Gap time, TS: Frame time, TP: 1 packet time → N to efficiently prevent data loss due to gap between frames, Derived S setting method

[Implementation evaluation]
・ Transmitter-5mm white LED, ATtiny10
Receiver-ASUS (registered trademark) ZenFone (registered trademark) 2 Laser ZE601KL (Android (registered trademark))
-Parameter setting-TP = 2.78 ms, N = 6, S = 2
・ Results-Realize lossless communication at a communication speed of 1.44 kbps.

[Summary]
・ “Compact, low cost”, “intuitive” LED-smartphone design ・ Packet repetitive transmission for packet loss countermeasures due to gap between frames ・ Packet loss with resource saving implementation by white LED of 5mm diameter and ATtiny10 Demonstrated that 1.44 kbps throughput can be achieved without

According to the number of retransmissions based on the frame time and gap time of the imaging device based on the rolling shutter method, the transmission time per packet of information configured by a plurality of packets and transmitted to the imaging device, and the number of packets of packets constituting the information A transmission apparatus comprising: a transmission control unit that performs transmission control of information; and a light emitting unit that transmits information by emitting light by a light emission pattern based on transmission control by the transmission control unit.

The number of retransmissions is based on a relational expression indicating that the number of packets is not less than the ratio of the product of the number of retransmissions and the transmission time and the sum of the gap time and the transmission time and not more than the ratio of the transmission time and the frame time. Specified transmitter.

The light emitting unit includes three or more light emitting elements, and at least one of the other light emitting elements is not disposed on the arrangement axis where at least two of the light emitting elements are disposed.

The packet includes identification information indicating whether the packet is the leading packet or the subordinate packet, and the amount of identification information indicating the subordinate packet out of the identification information is less than the amount of identification information indicating the leading packet. apparatus.

Light emission by the number of retransmissions based on an imaging unit using a rolling shutter system, a frame time and a gap time of the imaging unit, a transmission time per packet of information composed of a plurality of packets, and the number of packets of packets constituting the information A receiving device comprising: a light emitting unit that transmits information using a pattern; and a decoding unit that decodes information based on a light emission pattern image captured by the image capturing unit.

The decoding unit is a receiving device that decodes information by acquiring a temporal change of a light emission pattern indicated by a light emission pattern image by using a plurality of scanning rows.

A light emission pattern based on the number of retransmissions based on the frame time and gap time of the imaging unit using a rolling shutter system, the transmission time per packet of information composed of a plurality of packets, and the number of packets of packets constituting the information. A program for causing a light emitting unit that transmits information to acquire a light emission pattern image captured by the imaging unit, and a decoding step for decoding information based on the light emission pattern image acquired in the acquisition step .

[About rolling shutter]
FIG. 1 is a diagram illustrating an example of communication using a rolling shutter phenomenon.
As shown in FIG. 1, the smartphone captures 30 images per second. Here, the smartphone is an example of a receiving device or an imaging device.

The smartphone images the light from the light emitting unit 13 by a rolling shutter method. The rolling shutter system is a system that generates a captured image by sequentially exposing a part of an image sensor (not shown). In this example, the smartphone partially exposes every 100 μs. More specifically, the smartphone exposes the pixel row R1. When the pixel row R1 is exposed, the light emitting unit 13 emits light. For this reason, white indicating that the light emitting unit 13 emits light is recorded in the pixel corresponding to the pixel row R1 in the captured image.

Next, the smartphone exposes the pixel column R2 100 μs after imaging the pixel column R1. When the pixel row R2 is exposed, the light emitting unit 13 is turned off.
For this reason, black indicating that the light emitting unit 13 is turned off is recorded in the pixel corresponding to the pixel row R2 in the captured image.

Next, after 100 μs of imaging the pixel row R3, the smartphone exposes the pixel row R3. When the pixel row R3 is exposed, the light emitting unit 13 emits light.
For this reason, white indicating that the light emitting unit 13 emits light is recorded in the pixel corresponding to the pixel row R3 in the captured image. Similarly, the smartphone sequentially exposes all the pixel columns of the image sensor. It is also referred to as one frame that the imaging device sequentially exposes the pixel rows to take one image. A captured image captured by the smartphone is also referred to as a light emission pattern image. The smartphone includes a decoding unit that decodes information based on the light emission pattern image. Specifically, the decoding unit performs decoding based on information in which predetermined pixel information and information to be decoded are associated with each other. In this example, white and black included in the captured image are each one piece of information. More specifically, the decoding unit decodes white as 1 and black as 0. Note that the information decoded by the decoding unit is not limited to this. The decoding unit may decode white as 0 and black as 1.

[Example of packet loss]
Next, an example of packet loss will be described with reference to FIG.
FIG. 2 is a diagram illustrating an example of packet loss.
The imaging device generates a captured image for each frame described above. The time taken to image one frame is also referred to as a frame time. When the imaging device captures one frame, a gap time is generated. The gap time is a time during which imaging cannot be performed. The imaging device cannot capture light from the light emitting unit during the gap time. Information indicated by light emitted during the gap time is packet loss. Note that the frame time and the gap time have different lengths depending on the imaging device.

[Example of packet repeat communication method]
Next, referring to FIG. 3, the packet repetitive communication method will be described.
FIG. 3 is a diagram illustrating an example of a packet repetitive communication method.
The transmission device repeatedly transmits S times for each block composed of N packets. Here, a method for deriving a method for setting N and S for efficiently preventing data loss due to an inter-frame gap will be described. N is an integer indicating the number of packets transmitted at a time. The same applies to N in the mathematical expressions described below. S is an integer indicating the number of times of repeated transmission. The same applies to S in the following equations.

Expression (1) is a retransmission based on the frame time and gap time of the imaging device, the transmission time per packet of information configured by a plurality of packets and transmitted to the imaging device, and the number of packets of the packets constituting the information. This is an expression for deriving the number of times. Here, TF included in Equation (1) is the frame time of the imaging apparatus described above. TG included in Equation (1) is the gap time of the above-described imaging device. The TP included in Equation (1) is the time required to transmit one packet.

More specifically, in this retransmission count S, the packet count N is equal to or greater than the ratio of the product of the retransmission count N and the transmission time TP to the sum of the gap time TG and the transmission time TP, and the transmission time TP and the frame time. It is determined based on a relational expression indicating that the ratio is equal to or less than the ratio to TF. This relational expression is the above-described expression (1).
The transmission device includes a transmission control unit. The transmission control unit performs transmission control of information by repeatedly transmitting N packets calculated from Equation (1) S times.

[An example of a sequenceless packet]
Next, referring to FIG. 4, the sequencelessness of the packet will be described.
FIG. 4 is a diagram illustrating an example of a configuration of a sequenceless packet.

In this example, the packet includes identification information indicating whether the packet is the head packet or the subordinate packet. Of this identification information, the information amount of the identification information indicating the subordinate packet is smaller than the information amount of the identification information indicating the head packet. Specifically, a conventional packet is composed of a printable, a sequence portion, and a data portion. In this sequence part, information of Bsbit length is stored. One bit can represent a binary value. The binary values correspond to a state where the light emitting unit emits light and a state where the light emitting unit is turned off. In the data part, information on the BDbit length is stored.

In the sequenceless packet, four types of printables A0, A1, B0, and B1 are set as printables. In the following description, A0 and A1 are also indicated as A when they are not distinguished. In the following description, when B0 and B1 are not distinguished, they are also described as B. Different types of blocks are identified by A and B. As an example, A is allocated to even-numbered blocks. B is assigned to an odd-numbered block. In the following description, when A0 and B0 are not distinguished, they are also described as 0. When A1 and B1 are not distinguished, they are also described as 1. The order of packets in the block is determined based on 0 and 1. As an example, the leading packet is set to 0. Further, the packet other than the head is set to 1.

[Communication range expansion method]
Next, a communication range expansion method will be described with reference to FIG.
FIG. 5 is a diagram illustrating an example of a communication range expansion method.
The light emitting unit illustrated in FIG. 5 includes a plurality of light emitting elements. Light from a plurality of light emitting elements is exposed in the pixel column direction of the imaging device. The communication range expansion method is a method in which a light emitting unit is imaged as one captured image, and this captured image is selected as a demodulation point by scanning a plurality of columns. The scan direction is a direction perpendicular to the pixel row of the rolling shutter system. The decoding unit decodes the information by acquiring the temporal change of the light emission pattern indicated by the light emission pattern image by using a plurality of scan strings. Specifically, the smartphone sets a plurality of areas in the pixel column direction, and decodes information for each area. A plurality of regions is an example of a scan row. This region is a region based on the arrangement of a plurality of light emitting elements to be imaged. The smartphone exposes light from a plurality of light emitting elements corresponding to this region. The smartphone decodes light from the light emitting element for each region. Thereby, the smart phone can decode more information based on the captured image in which the information from a several light emitting element was contained in one pixel row.

5 (i) and 5 (iv) includes three or more light emitting elements, and at least one of the other light emitting elements is arranged on the arrangement axis on which at least two of the light emitting elements are arranged. It has not been. In the following description, the arrangement of the light emitting elements shown in FIGS. 5 (i) and 5 (iv) is also referred to as alternately arranging the light emitting elements. By arranging the light emitting elements alternately, the communicable range can be expanded while suppressing the communication error rate.

[Communication between IoT device and smartphone]
Next, communication between an IoT (Internet of Things) device and a smartphone will be described with reference to FIG.
FIG. 6 is a diagram illustrating an example of the transmission apparatus according to the first embodiment and an IoT device that performs wireless communication.
An IoT device is a device that allows a plurality of objects to exchange information. Conventional IoT devices using wireless communication have problems such as antennas for wireless communication and difficulty in operation. The transmission device of the present embodiment only needs to include an LED that is a light emitting unit, and can reduce the size and cost of production. In the transmission device of the present embodiment, the LED emits visible light. Thereby, the smart phone which is a receiver can be held over the light which an operator can visually recognize. With this operation, the operator can intuitively acquire information from the receiving device.

[Increased communication speed]
Next, an increase in communication speed will be described with reference to FIG.
FIG. 7 is a diagram illustrating a method for increasing the communication speed.
In order to increase the communication speed, S that is the number of repeated transmissions of one block may be minimized.
By substituting 2 for this S, this S is introduced into the above-described equation (1). It is calculated whether there exists N satisfying the formula (1) in which S is introduced. As described above, N is the number of packets constituting one block.
When N satisfying the above-described equation (1) exists, the S is the number of repeated transmissions minimized.
If there is no N satisfying the above-described expression (1), 1 is added to the value substituted for S until there is an N satisfying the expression (1), and whether there is an N satisfying the expression (1). calculate.

[Implementation evaluation]
Next, evaluation results of the transmission device and the reception device of the first embodiment will be described with reference to FIG.
FIG. 8 is a diagram illustrating an example of evaluation results of the transmission device and the reception device according to the first embodiment.
FIG. 8 shows the result of evaluating a smartphone which is a seven-type receiving device.

[Outline of Operation of Transmitting Device According to First Embodiment]
Next, an overview of the operation of the transmission apparatus according to the first embodiment will be described with reference to FIG.
FIG. 9 is a flowchart S1 illustrating an example of the operation of the transmission apparatus according to the first embodiment.

This transmission device includes a sensor, a transmission control unit, and a light emitting unit. The sensor measures the surrounding environment. The sensor generates measurement information indicating the measurement result. Here, the measurement information is an example of information. The transmission control unit performs measurement information transmission control by the transmission method described above. A light emission part transmits measurement information by light-emitting by the light emission pattern based on the transmission control by a transmission control part.

The transmission device acquires measurement information from the sensor (step S110). The transmission control unit converts the measurement information acquired from the sensor into a plurality of packets (step S120). The transmission control unit generates a light emission pattern based on the converted plurality of packets (step S130). This light emission pattern is a light emission pattern based on the number of retransmissions based on the transmission time per packet and the number of packets constituting the measurement information.

The transmission control unit changes the light emission state of the light emitting unit based on the generated light emission pattern (step S140). The transmission control unit determines whether or not the measurement information has been transmitted (step S150). If the transmission control unit has not finished transmitting the measurement information (step S150; NO), the transmission control unit reads the next light emission state from the generated light emission pattern (step S160). The transmission control unit changes the light emitting unit to the read light emission state. A transmission control part complete | finishes a process, when transmission of measurement information is complete | finished (step S150; YES).

As described above, the transmission device includes a light emitting unit and a transmission control unit. The transmission control unit performs information transmission control based on the number of retransmissions described above for a plurality of packets. The light emitting unit emits light with a light emission pattern based on transmission control of the transmission control unit. The receiving device includes an imaging unit and a decoding unit. The imaging unit images light from the transmission device as a light emission pattern by a rolling shutter method. The decoding unit decodes information output from the transmission device based on the light emission pattern image. The operator acquires information from the transmission device by imaging the transmission device using the imaging function of the reception device. As a result, the transmission device and the reception device can save time and effort for setting communication.
Further, since the transmission device can transmit information by light from the light emitting unit, the transmission device is a small casing as compared with a transmission device that performs wireless communication. Since the transmission device is a small housing, the manufacturing cost can be suppressed.

In the above description, although the rolling shutter method has been described with respect to the method for exposing each pixel row, the present invention is not limited to this. In the case of an image sensor that exposes each pixel row, it may be recorded for each pixel column. Further, in the rolling shutter system, exposure may be sequentially performed for each pixel. The smartphone may restore the information in the order of exposure by the rolling shutter system of the image sensor.

[Second Embodiment]
[Startup control of transmitter]
Next, a configuration in which information is exchanged between the transmission device and the reception device will be described with reference to FIG. In addition, about the structure and operation | movement same as 1st Embodiment mentioned above, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
FIG. 10 is a diagram illustrating an example of an external configuration of the transmission device 10 and the reception device 20 according to the second embodiment.

The transmitting device 10 operates with power from a battery (not shown). In this example, the transmission device 10 starts transmitting information when receiving light. The receiving device 20 acquires information transmitted from the transmitting device 10.
Specifically, the transmission device 10 includes a light receiving unit 13 that receives light. The light receiving unit 13 generates a light intensity signal indicating the intensity of the received light. The transmission device 10 starts outputting information when the light receiving unit 13 receives light. The transmission device 10 outputs measurement information measured by the sensor 14 by causing the light emitting unit 12 to emit light. The receiving device 20 images the light emission pattern emitted from the light emitting unit 12 by the imaging unit 21 as a light emission pattern image. The receiving device 20 decodes information based on the light emission pattern image. The receiving device 20 displays the decoded information on the display unit 23.

[Example of Configuration of Transmitting Device 10 and Receiving Device 20]
Next, the configuration of the transmission device 10 and the reception device 20 will be described with reference to FIG.
FIG. 11 is a diagram illustrating an example of the configuration of the transmission device 10 and the reception device 20.

The transmission device 10 includes a sensor 14, a calculation unit 11, a light emitting unit 12, a light receiving unit 13, and a start / stop unit 15. As described above, the sensor 14 measures the surrounding environment. The sensor 14 outputs the measured information as measurement information to the calculation unit 11.

The calculation unit 11 includes a signal acquisition unit 114, a reception signal generation unit 113, a transmission determination unit 112, and a transmission control unit 111. The signal acquisition unit 114, the reception signal generation unit 113, and the transmission determination unit 112 are examples of a light emission permission unit.
The signal acquisition unit 114 acquires a light intensity signal from the light receiving unit 13. The signal acquisition unit 114 outputs the light intensity signal acquired from the light receiving unit 13 to the reception signal generation unit 113.
The reception signal generation unit 113 acquires the light intensity signal from the signal acquisition unit 114. The received signal generation unit 113 stores the light intensity signals acquired from the signal acquisition unit 114 in the order of acquisition. The acquired light intensity signals arranged in chronological order are also referred to as blinking patterns. The reception signal generation unit 113 outputs the blink pattern to the transmission determination unit 112.

The transmission determination unit 112 permits the light emitting unit 12 to emit light when the light blinking pattern captured by the light receiving unit 13 is a predetermined blinking pattern. Specifically, the transmission determination unit 112 acquires a blinking pattern from the reception signal generation unit 113. The transmission determination unit 112 determines whether or not to transmit measurement information based on the blinking pattern acquired from the reception signal generation unit 113. In the following description, the result determined by the reception signal generation unit 113 is also referred to as a transmission determination result. The transmission determination unit 112 outputs the transmission determination result to the transmission control unit 111.

The transmission control unit 111 acquires measurement information from the sensor 14. The transmission control unit 111 acquires a transmission determination result from the transmission determination unit 112. Based on the transmission determination result acquired from the transmission determination unit 112, the transmission control unit 111 includes the frame time and gap time of the receiving device 20 using the rolling shutter method, and information that is configured by a plurality of packets and transmitted to the receiving device 20. Transmission control of the measurement information acquired from the sensor 14 is performed based on the number of retransmissions based on the transmission time per packet and the number of packets of the packets constituting the measurement information. In other words, the transmission control unit 111 controls the light emission state of the light emitting unit 12 by this transmission control.

The light emitting unit 12 emits light with a light emission pattern based on transmission control by the transmission control unit 111. In other words, the light emitting unit 12 performs the number of retransmissions based on the frame time and gap time of the imaging unit 21, the transmission time per packet of information composed of a plurality of packets, and the number of packets of the packets constituting the measurement information. The measurement information is transmitted by the light emission pattern. The light emitting unit 12 outputs measurement information based on the light emission pattern.

The start / stop unit 15 starts or stops at least one of the transmission control unit 111, the light emitting unit 12, and the light receiving unit 13 based on a predetermined condition. In this example, the start / stop unit 15 starts or stops the calculation unit 11. Here, the predetermined condition, which is a condition for the activation / stop unit 15 to activate or deactivate, is a time based on the blinking interval of light received by the light receiving sensor. Specifically, the predetermined condition includes at least one of a condition for elapse of time, a condition for determining whether or not the light receiving unit 13 receives light, and a condition for determining whether the blink pattern is a predetermined blink pattern. One condition.
More specifically, the activation stop unit 15 activates the calculation unit 11 as a predetermined time elapses. When the transmission determination result of the transmission determination unit 112 determines that transmission is to be performed, the start / stop unit 15 does not stop the calculation unit 11 under the time elapse condition. The start / stop unit 15 stops the calculation unit 11 when it is determined that the transmission determination result of the transmission determination unit 112 is not transmitted.

The receiving device 20 includes an imaging unit 21, a decoding unit 22, a display unit 23, a light emission control unit 24, and a flash 25.
The imaging unit 21 captures an image using a rolling shutter method.
The decoding unit 22 decodes the measurement information based on the light emission pattern image. The light emission pattern image is an image in which the light emitting unit 12 is imaged by the imaging unit 21. The decoding unit 22 causes the display unit 23 to display the decoded measurement information. The display unit 23 displays measurement information.

The light emission control unit 24 blinks the flash 25.

[Outline of operation of transmitting apparatus 10]
Next, an outline of the operation of the transmission apparatus 10 will be described with reference to FIG.
FIG. 12 is a flowchart S <b> 2 illustrating an example of the operation of the transmission device 10. Note that the processing procedure shown here is an example, and the processing procedure may be omitted or a processing procedure may be added.

The activation stop unit 15 activates the sensor 14 (step S210). The activation stop unit 15 activates the calculation unit 11 (step S220).
The signal acquisition unit 114 acquires a light intensity signal from the sensor 14. The signal acquisition unit 114 supplies the light intensity signal acquired from the sensor 14 to the reception signal generation unit 113. The reception signal generation unit 113 acquires the light intensity signal from the signal acquisition unit 114. The reception signal generation unit 113 generates a blinking pattern based on the light intensity signal acquired from the signal acquisition unit 114. The reception signal generation unit 113 supplies the generated blinking pattern to the transmission determination unit 112. The transmission determination unit 112 acquires a blinking pattern from the reception signal generation unit 113. The transmission determination unit 112 performs transmission determination based on the blinking pattern acquired from the reception signal generation unit 113 (step S230). The reception signal generator 113 determines whether or not the activation condition is satisfied (step S240).

When the predetermined condition is satisfied (step S240; YES), the reception signal generation unit 113 stops the start or stop operation of the start / stop unit 15 and executes the process of the flowchart S1.

If the predetermined condition is not satisfied (step S240; NO), the reception signal generation unit 113 causes the start / stop unit 15 to stop the operation of the calculation unit 11 (step S250). The start / stop unit 15 does not process anything for a predetermined time (step S260). The start / stop unit 15 repeats the processing from step S210 after a predetermined time has elapsed.

Here, a specific example of the operation determined by the transmission determination unit 112 will be described with reference to FIG.
FIG. 13 is a diagram illustrating an example of the operation of the transmission determination unit 112.
FIG. 13A is a diagram in which the light emission states of the flash 25 are arranged in time series. FIG. 13B is a diagram illustrating an example of a blinking pattern received by the light receiving unit 13.

The light emission state of the flash 25 is off from time t0 to time t1. The light receiving unit 13 does not receive light from time t0 to time t1. In addition, the start / stop unit 15 repeats starting and stopping of the calculation unit 11 eight times from time t0 to time t1.
The time interval Tsleep is an example of the predetermined time shown in step S260 described above.

In this example, the flash 25 emits light with the light emission pattern FPT1. Specifically, the light emission state of the flash 25 is a lighting state from time t1 to time t2. In the following description, the time during which the flash 25 is kept on is also referred to as a time interval Tflash. The light receiving unit 13 receives light between time t1 and time t2. Similarly, the light emission state of the flash 25 is a lighting state from time t3 to time t4, from time t5 to time t6, and from time t7 to time t8. Similarly, the light receiving unit 13 receives light from time t3 to time t4, from time t5 to time t6, from time t7 to time t8, and from time t1 to time t2.

The light emission state of the flash 25 is off from time t2 to time t3. The light receiving unit 13 does not receive light between time t2 and time t3. Similarly, the light emission state of the flash 25 is off from time t4 to time t5, from time t6 to time t7, and from time t7 to time t8. Similarly, the light receiving unit 13 does not receive light from time t4 to time t5, from time t6 to time t7, and from time t7 to time t8.

In this example, the blink pattern includes four consecutive blinks. Since the four consecutive blink patterns are the predetermined blink patterns, the transmission determination unit 112 permits the transmission control unit 111 to transmit. In other words, the transmission determination unit 112 permits the light emitting unit 12 to emit light because the light blinking pattern captured by the light receiving unit 13 is a predetermined blinking pattern. The transmission device 10 starts outputting measurement information.

[About control of stop time]
Next, a configuration for controlling the stop time of the computing unit 11 will be described with reference to FIG.
FIG. 14 is a diagram illustrating an example of the operation of the start / stop unit 15 in which the stop time is controlled.
FIG. 14A is a diagram in which the light emission states of the flash 25 are arranged in time series. FIG. 14B is a diagram illustrating an example of a blinking pattern received by the light receiving unit 13.

In this configuration, the transmission determining unit 112 emits light from the light emitting unit 12 based on the determination result of whether or not the light receiving unit 13 is receiving light during the period in which the activation stopping unit 15 activates the transmission determining unit 112. Allow. Specifically, the time interval Tsleep1 shown in FIG. 14B is longer than the above-described time interval Tsleep. This is because the start / stop unit 15 changes the time lapse condition, which is a predetermined condition of the start / stop unit 15, to a longer time lapse condition when the light receiving unit 13 continues to receive no light a plurality of times. It is because it is changed. The start / stop unit 15 is changed to a stop time of the time interval Tsleep2 when the light receiving unit 13 receives light. This time interval Tsleep2 is the same time as the time interval Tsleep described above.

Specifically, the light emission state of the flash 25 is in the off state from time t20 to time t21. The light receiving unit 13 does not receive light from time t20 to time t21. The interval from time t20 to time t21 is the time interval Tsleep1 described above.
The start / stop unit 15 repeats starting and stopping of the calculation unit 11 three times from time t20 to time t23.

In this example, the flash 25 emits light with the light emission pattern FPT1 described above. Specifically, the light emission state of the flash 25 is a lighting state from time t23 to time t24. Similarly, the light emission state of the flash 25 is a lighting state from time t25 to time t26, from time t27 to time t28, and from time t29 to time t30. The light emission state of the flash 25 is off from time t24 to time t25. Similarly, the light emission state of the flash 25 is a light-off state between time t26 and time t27 and between time t28 and time t29.
The light receiving unit 13 does not receive light from time t23 to time t24 because the calculation unit 11 is stopped. Similarly, from time t24 to time t27, the light receiving unit 13 does not receive light because the calculation unit 11 is stopped. The light receiving unit 13 receives light from time t27 to time t28 and from time t29 to time t30, respectively.

Here, when the time interval Tflash and the time interval Tsleep2 are set to substantially the same time interval, the blinking included in the predetermined blinking pattern determined by the transmission determination unit 112 may be performed twice. Thereby, the frequency | count of determination of starting or a stop until the transmitter 10 outputs measurement information can be suppressed. Thereby, the transmission apparatus 10 can shorten time until transmission of measurement information to the reception apparatus 20 is started.

As described above, the transmission device 10 may change the time elapse condition according to the light receiving state of the light receiving unit 13. Thereby, the transmission apparatus 10 can suppress power consumption more than the case where the conditions of time passage are not changed.

[Light intensity signal]
The transmission determination unit 112 may determine whether the light from the flash 25 is received or whether ambient light is received based on the intensity of light received by the light receiving unit 13. In this case, the blinking pattern only needs to include information indicating the intensity of light.
Specifically, the transmission determining unit 112 compares the intensity of the light received immediately before with the latest received light intensity. More specifically, the transmission determining unit 112 receives the received light when the difference between the intensity of the previously received light and the intensity of the latest received light is higher than a predetermined threshold. It is determined that the light is from the device 20. The transmission determining unit 112 determines that the received light is the environmental light when the difference between the intensity of the light received immediately before and the intensity of the latest received light is lower than a predetermined threshold. judge.

Thereby, the transmission determination unit 112 suppresses erroneous transmission due to ambient light. By suppressing erroneous transmission, the power consumption of the transmission device 10 can be further suppressed. Moreover, the transmission determination part 112 can suppress the frequency | count of determination of starting or a stop until outputting measurement information. Thereby, the transmission apparatus 10 can shorten time until transmission of measurement information to the reception apparatus 20 is started.

[Summary of Second Embodiment]
The transmission device 10 includes a start / stop unit 15, a calculation unit 11, a light receiving unit 13, and a light emitting unit 12. The calculation unit 11 includes a transmission control unit 111 and a transmission determination unit 112.
The start / stop unit 15 starts or stops the operation of the calculation unit 11 based on a predetermined condition.
The transmission determination unit 112 determines whether to transmit information based on the blinking pattern of light received by the light receiving unit 13 during activation. The transmission control unit 111 starts light emission control of the light emitting unit 12 when the transmission determination unit 112 determines to transmit information. Thereby, the transmission apparatus 10 can suppress power consumption. Since the transmission device 10 can suppress power consumption, it can operate for a long period of time. Since the transmission apparatus 10 can operate for a long period of time, it can be set in a place where it is not necessary to acquire frequently measured information or a place where there is no existing wireless communication network.

In the above description, the transmission determination unit 112 determines that transmission is performed in the case of a predetermined blinking pattern, but this is not essential. The transmission determination unit 112 may determine to transmit even when the light receiving unit 13 receives light once. The transmission determination unit 112 can suppress transmission by ambient light other than the flash 25 in the case where the transmission determination unit 112 determines that transmission is performed in the case of a predetermined blinking pattern. Thereby, the transmission apparatus 10 can suppress power consumption.

In the above description, the start / stop unit 15 has been described to be configured to start or stop the calculation unit 11, but is not limited thereto. The start / stop unit 15 may have a sleep function when the calculation unit is a microcomputer. The sleep function is a function that alternately repeats starting and stopping of the microcomputer with a predetermined time interval. In other words, the calculation unit 11 may include a start / stop unit 15. When the start / stop unit 15 has a sleep function, the number of components constituting the start / stop unit 15 can be reduced. For this reason, the transmitter 10 can be configured at low cost.
Further, the start / stop unit 15 may be configured to switch the energization state of the light emitting unit 12.
In the case of this configuration, the transmission device 10 can suppress the power consumed by the light emitting unit 12 emitting light.

In the above description, the transmission apparatus 10 has been described with respect to the case where communication is performed by causing the light control unit 111 to control the light emitting unit 12 to blink the light, but is not limited thereto. The transmission device 10 may transmit information to the reception device 20 by other methods such as wireless communication. In other words, the transmission device 10 may include a light receiving sensor that receives light, and may be a transmission device that starts transmitting information based on a blinking pattern of light captured by the light receiving sensor.
As described above, the transmission device 10 is driven by a battery having a limited amount of power that can be used. The transmission device 10 can suppress the amount of power used for detecting the blinking pattern of light by having a period in which the light receiving unit 13 receives light and a period in which light is not received.

[Third Embodiment]
[About bidirectional communication]
Up to this point, the configuration in which the transmission device starts transmitting measurement information has been described. Next, a configuration in which the transmission device 10a and the reception device 20a perform two-way communication will be described with reference to FIG. In addition, about the same structure and operation | movement as 1st Embodiment and 2nd Embodiment mentioned above, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
FIG. 15 is a diagram illustrating an example of the configuration of the transmission device 10a according to the third embodiment.

When receiving the light, the transmitting device 10a starts transmitting information. The receiving device 20a acquires information transmitted from the transmitting device 10.
Specifically, the transmission device 10a includes a light receiving unit 13 that receives light. When the light receiving unit 13 receives light, the transmission device 10a starts outputting information. The transmission device 10a outputs measurement information measured by the sensor 14 by causing the light emitting unit 12 to emit light. The receiving device 20a captures the light emission pattern emitted from the light emitting unit 12 by the imaging unit 21 as a light emission pattern image. The receiving device 20a decodes information based on the light emission pattern image. The receiving device 20a causes the flash 25 to emit a response pattern that is a light emission pattern corresponding to the decoded information. The light receiving unit 13 receives the response pattern from the flash 25. The transmission device 10a determines whether or not the transmitted measurement information has been received normally based on the received response pattern.

The transmission device 10a includes a calculation unit 11a. The calculation unit 11a includes a transmission control unit 111a, a retransmission control unit 115, a reception state determination unit 116, and a signal acquisition unit 114.

The transmission control unit 111a acquires measurement information from the sensor 14. The transmission control unit 111 includes a frame time and a gap time of the receiving device 20a using a rolling shutter method, a transmission time per packet of information configured by a plurality of packets and transmitted to the receiving device 20a, and a packet constituting measurement information The transmission control of the measurement information acquired from the sensor 14 is performed based on the number of retransmissions based on the number of packets. In this example, the transmission control unit 111a transmits information for each segment. A segment is composed of a plurality of packets. The transmission time of this segment includes the reception delay time of the segment of the receiving device 20a, the light emitting state in which the light of the flash 25 that emits light from the receiving device 20a is emitted, and the non-light emitting state in which no light is emitted. It is longer than the time required for switching.

Also, the transmission control unit 111a acquires retransmission information from the retransmission control unit 115. The retransmission information is a signal indicating a request for retransmission of a packet that has already been transmitted.

The reception state determination unit 116 determines the reception state of information of the reception device 20 a based on the light reception state of the light receiving unit 13. Specifically, the reception state determination unit 116 determines that the reception device 20a has received information when the light receiving unit 13 receives light. When the light receiving unit 13 is not receiving light, the reception state determination unit 116 determines that the receiving device 20a cannot receive information.
The retransmission control unit 115 causes the transmission control unit 111a to retransmit the segment based on the determination result determined by the reception state determination unit 116. Specifically, when the reception state determination unit 116 determines that the information has not been received, the retransmission control unit 115 sends retransmission information indicating packet retransmission to the transmission control unit 111a. Output.

When the transmission control unit 111a acquires a retransmission signal from the retransmission control unit 115, the transmission control unit 111a retransmits the previous segment.

The receiving device 20a includes an imaging unit 21, a decoding unit 22a, a display unit 23, a light emission control unit 24a, and a flash 25.

The decoding unit 22a decodes the measurement information based on the light emission pattern image. The light emission pattern image is an image in which the light emitting unit 12 is imaged by the imaging unit 21.
When the packet included in the segment can be decoded, the decoding unit 22a outputs decoding success information indicating that decoding is successful to the light emission control unit 24a. The decoding unit 22a causes the display unit 23 to display the decoded measurement information.
When the packet included in the segment cannot be decoded, the decoding unit 22a outputs decoding failure information indicating that the decoding has failed to the light emission control unit 24a.

The light emission control unit 24a causes the flash 25 to emit a light emission pattern corresponding to the reception state of the measurement information of the own device. Specifically, the light emission control unit 24a acquires decoding success information or decoding failure information from the decoding unit 22a. The light emission control unit 24a causes the flash 25 to emit light when the decoding success information is acquired. The light emission control unit 24a turns off the flash 25 when the decoding failure information is acquired.

[Outline of Operation of Transmitting Device According to Third Embodiment]
Next, an outline of the operation of the transmission device 10a will be described with reference to FIG.
FIG. 16 is a flowchart S3 illustrating an example of the operation of the transmission device 10a. Note that the processing procedure shown here is an example, and the processing procedure may be omitted or a processing procedure may be added.

The reception state determination unit 116 starts monitoring the reception state of the reception device 20a (step S310). The receiving device 20a maintains the lighting state of the flash 25 when it is in a receivable state. The transmission control unit 111a transmits the first segment (step S320). The imaging unit 21 images the first segment. The transmission control unit 111a transmits a second segment that is the next segment after the first segment (step S330). Here, the decoding unit 22a determines whether or not all the packets included in the first segment have been decoded.
When the first segment cannot be decoded, the decoding unit 22a outputs decoding failure information to the light emission control unit 24a. The light emission control unit 24a turns off the flash 25 when the decoding failure information is acquired. The reception state determination unit 116 determines whether retransmission is necessary (step S340).

When retransmission is necessary (step S340; YES), the retransmission control unit 115 outputs a retransmission signal to the transmission control unit 111a. The transmission control unit 111a acquires a retransmission signal from the transmission control unit 111a. The transmission control unit 111a transmits the first segment, which is the previous segment (step S350). The transmission control unit 111a repeats step S330 to step S340.
If re-transmission is not necessary (step S340; NO), the transmission control unit 111a determines whether or not transmission of all measurement information has been completed (step S360).

If transmission of all measurement information has not been completed (step S360; NO), the remaining segments are sequentially transmitted.
If all the transmission of measurement information has been completed (step S360; YES), the reception state determination unit 116 ends the monitoring of the reception state of the reception device 20a (step S370).

[Specific examples of bidirectional communication]
Next, an example of bidirectional communication between the transmission device 10a and the reception device 20a will be described with reference to FIG.
FIG. 17 is a diagram illustrating an example of bidirectional communication between the transmission device 10a and the reception device 20a.

The transmission device 10a transmits the segment SEG120 between time t70 and time t71. The segment SEG120 starts to be received by the receiving device 20a at time t80 and ends at time t81. The decoding unit 22a decodes the packet included in the segment SEG120. The decryption unit 22a turns off the flash 25 when the decryption fails.

It takes a time obtained by adding the time interval TR and the time interval TFC from the completion of the transmission of the segment SEG 120 until the transmission device 10a detects a change in the state of the flash 25 as a transmission result. Here, the time interval TR is a reception delay time until the receiving device 20a receives the segment SEG120. The time interval TFC is a time required for switching the light emission state of the receiving device 20a. Note that the time interval Tsensor shown in FIG. 17 is the time required for reading by the sensor 14. In addition, the time interval Tc shown in FIG. 17 is a time required for the re-transmission control of the segment by the receiving device 20a.

The transmission device 10a transmits the segment SEG121 between time t72 and time t73. The segment SEG 121 starts to be received by the receiving device 20a at time t82 and ends at time t84. While transmitting the segment SEG 121, the transmission device 10a checks the light emission state of the flash 25. Here, since decoding of the segment SEG 120 has failed, the receiving device 20a turns off the flash 25 from time t83 to time t86. The transmission device 10a confirms that the flash 25 is turned off while the segment SEG 121 is being transmitted.

The transmission device 10a retransmits the segment SEG120 in which the reception device 20a failed to decode between time t74 and time t75. The receiving device 20a receives the retransmitted segment SEG120 between time t85 and time t87.
The transmitting apparatus 10a checks the reception state of the segment SEG 121 while retransmitting the segment SEG 120. The transmitting apparatus 10a confirms the reception state of the segment SEG121 between time t86 and time t89.

The transmission device 10a transmits the segment SEG122 after the re-transmission of the segment SEG120. The segment SEG 122 is transmitted from time t76 to time t77. The receiving device 20a receives the segment SEG122 between time t88 and time t90.

[Specific example of bidirectional communication # 2]
Up to this point, the receiving device 20a performs communication by turning on the flash 25 when the packet included in the segment is successfully decoded and turning off the flash 25 when decoding of the packet included in the segment fails. The method was explained. Here, there is a case where environmental light, which is light other than the flash 25 provided in the receiving device 20a, is disposed outdoors and is misrecognized as light indicating that the packet has been successfully decoded.

Next, an example of second bidirectional communication between the transmission device 10a and the reception device 20a that suppresses this erroneous recognition will be described with reference to FIG.
FIG. 18 is a diagram illustrating an example of second bidirectional communication between the transmission device 10a and the reception device 20a.
In the second bidirectional communication, the receiving device 20a changes the lighting state of the flash 25 when the packet decoding is successful. In the second bidirectional communication, the receiving device 20a does not change the lighting state of the flash 25 when the packet decoding fails. The lighting state of the flash 25 is a state where the flash 25 is turned on and a state where the flash 25 is turned off. The operation other than changing the lighting state of the flash 25 according to the successful decoding of the packet and not changing the lighting state of the flash 25 when the packet decoding fails is the same operation as the above-described bidirectional communication.

The transmission device 10a transmits the segment SEG180 between time t180 and time t181. The segment SEG 180 starts to be received by the receiving device 20a at time t190 and ends at time t191. The decoding unit 22a decodes the packet included in the segment SEG180. Since the decoding unit 22a has successfully decoded the packet of the segment SEG180, the decoding unit 22a changes the lighting state of the flash 25 at time t193. In this example, the flash device 25 is turned on when the receiving device 20a starts decoding the segment SEG180. For this reason, since the receiving device 20a has successfully decoded the segment SEG180 packet, the receiving device 20a turns off the flash 25 at time t193.

The transmission device 10a transmits the segment SEG181 between time t182 and time t183. The segment SEG181 is received by the receiving device 20a at time t192, and is ended at time t194. While transmitting the segment SEG181, the transmission device 10a determines whether the light receiving unit 13 is receiving light, thereby confirming the light emission state of the flash 25 of the transmission device 10a. Here, since the segment SEG 180 has been successfully decoded, the receiving device 20a turns off the flash 25 from time t192 to time t194. The reception state determination unit 116 determines that the segment SEG180, which is the previous segment, has been received by determining that the flash 25 is turned off during transmission of the segment SEG181.

Upon receiving the segment SEG181, the decoding unit 22a decodes the packet included in the segment SEG181. Since the decoding unit 22a failed to decode the packet of the segment SEG181, the lighting state of the flash 25 is not changed at time t196. In this example, the flash device 25 is turned off at the time when the receiving device 20a starts decoding the segment SEG181. For this reason, the receiving device 20a does not change the lighting state of the flash 25 at time t195 because the decoding of the packet of the segment SEG181 has failed. In other words, the receiving device 20a keeps the flash 25 off at time t195.

The transmission device 10a transmits the segment SEG182 between time t184 and time t185. The segment SEG182 starts to be received by the receiving device 20a at time t195 and ends at time t197. While transmitting the segment SEG182, the transmission device 10a determines whether the light receiving unit 13 is receiving light, thereby confirming the light emission state of the flash 25 of the transmission device 10a. Here, since decoding of the segment SEG 181 has failed, the receiving device 20a turns off the flash 25 from time t196 to time t199. The reception state determination unit 116 determines that the segment SEG 181 has not been received by determining that the lighting state of the flash 25 remains off.

Upon receiving the segment SEG182, the decoding unit 22a decodes the packet included in the segment SEG182. Since the decoding unit 22a has successfully decoded the packet of the segment SEG182, the decoding unit 22a changes the lighting state of the flash 25 at time t199. At the time when the receiving device 20a starts decoding the segment SEG182, the flash 25 is turned off. For this reason, since the receiving device 20a has successfully decoded the segment SEG182 packet, the receiving device 20a turns on the flash 25 at time t199.

The transmitting apparatus 10a retransmits the segment SEG181 in which the receiving apparatus 20a failed to decode between time t186 and time t187. The receiving device 20a receives the retransmitted segment SEG181 between time t197 and time t19A.
While retransmitting the segment SEG181, the transmission device 10a checks the reception status of the segment SEG182. The transmission device 10a determines the reception state of the segment SEG182 between time t199 and time t19C. The transmission device 10a determines that the segment SEG182 has been received by determining that the lighting state of the flash 25 has changed.

The transmission device 10a transmits the segment SEG183 after the re-transmission of the segment SEG181. The segment SEG183 is transmitted from time t188 to time t189. The receiving device 20a receives the segment SEG183 between time t19C and time t19D.

As described above, the receiving device 20a that performs the second two-way communication changes the lighting state of the flash 25 when successfully decoding the packet included in the segment, and decodes the packet included in the segment. If it fails, the lighting state of the flash 25 is not changed. By comprising in this way, it can suppress that the result of communication between the transmitter 10a and the receiver 20a is misrecognized by environmental light. Thereby, the transmission device 10a can stabilize communication with the reception device 20a.

Further, the transmission device 10a may stop the segment transmission when it is determined that the packet decoding has failed a predetermined number of times. In general, the ambient light changes more irregularly than the change in the lighting state of the flash 25. By determining that the packet has been successfully decoded by the change in the lighting state of the flash 25, the transmitting device 10a has a shorter time than when determining that the packet has been successfully decoded by turning on the flash 25. You can stop sending segments. That is, when the position of the receiving device 20a moves and the segment cannot be received during the two-way communication, the transmitting device 10a can stop the segment transmission in a shorter time. Thereby, the transmission apparatus 10a can suppress consumption of the electric power of the battery with which the transmission apparatus 10a is provided.

[Summary of Third Embodiment]
As described above, the transmission device 10a includes the calculation unit 11a. The computing unit 11a includes a transmission control unit 111a, a retransmission control unit 115, and a reception state determination unit 116.
The transmission device 10a transmits the segment without waiting for the delay of the reception device 20a. The reception state determination unit 116 determines whether or not the reception device 20a has successfully received the segment based on the light reception state of the light receiving unit 13. If the result determined by the reception state determination unit 116 indicates that retransmission is necessary, the retransmission control unit 115 causes the transmission control unit 111a to retransmit the previous segment. Thereby, the transmission device 10a transmits information regardless of the reception state of the reception device 20a. Further, the transmission device 10a retransmits only the segments that the reception device 20a could not receive. Thereby, the transmission apparatus 10a can transmit information efficiently.

In the above description, the transmission control unit 111a transmits the measurement information for each segment, but is not limited thereto. The transmission control unit 111a may transmit measurement information for each packet.

In the above description, the transmission control unit 111a has described the configuration for retransmitting the previously transmitted segment, but is not limited thereto. The transmission control unit 111a may retransmit from the head segment of the information.

In the above description, the transmission control unit 111 included in the transmission apparatuses of the second embodiment and the third embodiment includes information, which includes a frame time and a gap time of an imaging apparatus using a rolling shutter method, and a plurality of packets. Although a case has been described in which transmission is performed based on the number of retransmissions based on the transmission time per packet of information transmitted to the imaging apparatus and the number of packets of packets constituting the information, the present invention is not limited to this. The transmission control unit 111 of the second embodiment and the third embodiment may transmit information by other transmission methods.

Note that the transmission apparatuses from the first embodiment to the third embodiment described above may emit a light emission pattern indicating that the transmission of information is completed when the transmission of information is completed. The receiving device ends the imaging based on the light emission pattern indicating that the transmission of information has ended.
Thereby, the receiving device can determine that all the information from the transmitting device has been received. Specifically, information indicating that the transmission of information has been completed may be set in the above-described packet printable in the light emission pattern indicating that the transmission of information has been completed.

In addition, you may combine how the structure of the transmission apparatus from 1st Embodiment mentioned above to 3rd Embodiment mentioned above.

The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and appropriate modifications may be made without departing from the spirit of the present invention. it can.

It should be noted that the program for realizing the functions of the arbitrary components in the transmission device, the reception device, the transmission device 10, the transmission device 10a, the reception device 20, and the reception device 20a described above is recorded on a computer-readable recording medium (memory). The program may be recorded (stored) on a medium, and the program may be read into a computer system and executed. The “computer system” here includes an operating system (OS) or hardware such as peripheral devices. The “computer-readable recording medium” means a portable disk such as a flexible disk, a magneto-optical disk, a ROM (Read Only Memory), a CD (Compact Disc) -ROM, or a hard disk built in the computer system. Refers to the device. Further, the “computer-readable recording medium” means a volatile memory (RAM: Random Access) inside a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. Memory that holds a program for a certain period of time, such as Memory).

The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
Further, the above program may be for realizing a part of the functions described above. Further, the above program may be a so-called difference file (difference program) that can realize the above-described functions in combination with a program already recorded in the computer system.

DESCRIPTION OF SYMBOLS 10,10a ... Transmitter, 11, 11a ... Calculation part, 12 ... Light emission part, 13 ... Light-receiving part,
... sensor, 15 ... start / stop unit, 20, 20a ... receiving device, 21 ... imaging unit, 22, 22a ...
Decoding unit, 23 ... display unit, 24 ... light emission control unit, 25 ... flash, 111, 111a ... transmission control unit, 112 ... transmission determination unit, 113 ... received signal generation unit, 114 ... signal acquisition unit, 115 ...
Retransmission control unit, 116 ... reception state determination unit

Claims (16)

1. Retransmission based on the frame time and gap time of the imaging device using the rolling shutter method, the transmission time per packet of information configured by a plurality of packets and transmitted to the imaging device, and the number of packets of the packets constituting the information A transmission control unit that performs transmission control of the information according to the number of times;
   A light emitting unit that transmits the information by emitting light by a light emission pattern based on transmission control by the transmission control unit.
2. The number of retransmissions is
   Relational expression indicating that the number of packets is equal to or greater than a ratio of a product of the number of retransmissions and the transmission time and a sum of the gap time and the transmission time, and is equal to or less than a ratio of the transmission time and the frame time. The transmission apparatus according to claim 1, wherein the transmission apparatus is determined based on
3. The light emitting unit
   The transmission device according to claim 1, further comprising: three or more light emitting elements, wherein at least one of the other light emitting elements is not disposed on an arrangement axis on which at least two of the light emitting elements are disposed. .
4. The packet includes identification information indicating whether the packet is a head packet or a subordinate packet,
   The transmission apparatus according to any one of claims 1 to 3, wherein an information amount of identification information indicating a subordinate packet among the identification information is smaller than an information amount of identification information indicating a leading packet.
5. It has a light receiving sensor that receives light,
   A transmission device that starts transmission of information based on a flickering pattern of light captured by the light receiving sensor.
6. Based on the frame time and gap time of the imaging device based on the rolling shutter method, the transmission time per packet of the information that is configured by a plurality of packets and transmitted to the imaging device, and the number of packets of the packets constituting the information A transmission control unit that performs transmission control of the information according to the number of retransmissions;
   A light emitting unit for transmitting the information by emitting light by a light emission pattern based on transmission control by the transmission control unit;
   The transmission device according to claim 5, further comprising an activation stop unit that activates or stops at least one of the transmission control unit, the light emitting unit, and the light receiving sensor based on a predetermined condition.
7. The transmission device according to claim 6, further comprising: a light emission permission unit that permits light emission of the light emitting unit when a light blinking pattern captured by the light receiving sensor is a predetermined blinking pattern.
8. The predetermined condition is a time based on a blinking interval of light received by the light receiving sensor,
   The start / stop unit starts and stops the light emission permission unit based on the predetermined condition,
   The light emission permission unit permits light emission of the light emission unit based on a determination result of whether or not the light receiving sensor receives light during a period in which the activation stop unit activates the light emission permission unit. Item 8. The transmission device according to Item 7.
9. A transmission control unit for performing transmission control of information;
   A light emitting unit for transmitting the information by emitting light by a light emission pattern based on transmission control by the transmission control unit;
   A light receiving sensor for receiving light;
   A reception state determination unit that determines a reception state of the information based on a light reception state of the light reception sensor;
   A transmission apparatus comprising: a retransmission control unit that causes the transmission control unit to retransmit the information based on a determination result determined by the reception state determination unit.
10. The information is transmitted for each segment composed of a plurality of packets, and the transmission time of the segment is the reception delay time of the segment of the imaging device and the light emitting unit of the imaging device that emits light. A time longer than a time taken to switch between a light emitting state in which light is emitted and a non-light emitting state in which the light is not emitted,
    The retransmission control unit
    The transmission device according to claim 9, wherein a segment transmitted by the device itself one time before is retransmitted as the information.
11. A transmission control unit for performing transmission control of information;
    A light emitting unit that transmits the information by emitting light by a light emission pattern based on transmission control by the transmission control unit;
    The transmission control unit
    A transmission device that emits a light emission pattern indicating that transmission of the information is completed when transmission of the information is completed.
12. The transmission control unit
    The information includes a frame time and a gap time of an imaging device using a rolling shutter method, a transmission time per packet of the information that is configured by a plurality of packets and is transmitted to the imaging device, and a packet of a packet that constitutes the information The transmission device according to any one of claims 9 to 11, wherein the transmission is performed based on the number of retransmissions based on the number.
13. An imaging unit using a rolling shutter system;
    The information is transmitted by a light emission pattern based on the number of retransmissions based on the frame time and gap time of the imaging unit, the transmission time per packet of information composed of a plurality of packets, and the number of packets of the packets constituting the information. And a decoding unit that decodes the information based on a light emission pattern image captured by the imaging unit.
14. A light emitting unit that emits light;
    The receiving device according to claim 13, further comprising: a light emission control unit that causes the light emitting unit to emit a light emission pattern according to a reception state of the information of the device itself.
15. The decoding unit
    The receiving device according to claim 13 or 14, wherein the information is decoded by acquiring temporal changes of the light emission pattern indicated by the light emission pattern image by a plurality of scanning rows.
16. On the computer,
    According to the light emission pattern based on the number of retransmissions based on the frame time and gap time of the imaging unit by the rolling shutter method, the transmission time per packet of information composed of a plurality of packets, and the number of packets of the packets constituting the information An acquisition step in which a light emitting unit that transmits information acquires a light emission pattern image captured by the imaging unit;
    And a decoding step of decoding the information based on the light emission pattern image acquired in the acquisition step.

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