JP2019092123A - Communication apparatus, slave unit, communication system, and program - Google Patents

Abstract

To provide a communication apparatus capable of simplifying signals, a slave unit, a communication system, and a program.SOLUTION: A master unit 1 includes: a master unit side communication unit 14; and a master unit side control unit 12. The master unit side communication unit 14 is configured to transmit a synchronization signal to a slave unit 2. The master unit side control unit 12 is configured to control the master unit side communication unit 14. The synchronization signal is a signal for synchronizing the master unit 1 and the slave unit 2, in which the signal level periodically switches between at least two values. The master unit side control unit 12 modulates at least one of the period in which the signal level of the synchronization signal switches between two values and the duty which is a ratio of period in which the signal level is one of the two values in the period according to the information to be transmitted to the slave unit 2.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates generally to communication devices, slaves, communication systems, and programs, and more particularly to communication devices, slaves, communication systems, and programs that transmit synchronization signals.

  Conventionally, a load control system (communication system) in which an image sensor (communication device) and a transmission control device are connected by a two-wire signal line is disclosed (for example, see Patent Document 1). The load control system described in Patent Document 1 includes an image sensor, a display terminal, and a transmission control device. The image sensor captures a space of a detection target, and detects the presence or absence of a person in a detection area set in advance among the captured images. The display terminal has a display unit that displays a detection area. In the transmission control device, the image sensor and the display terminal are connected via a two-wire signal line.

  The image sensor is configured to transmit a transmission signal including area data indicating a detection area to the transmission control device via the signal line. Further, the transmission control device is configured to transmit a transmission signal including the area data transmitted from the image sensor and the address data matching the address of the display terminal to the display terminal via the signal line. The display terminal is configured to display the detection area on the display unit based on the area data.

JP, 2015-152314, A

  In the load control system described in Patent Document 1, the transmission control device is configured to transmit a transmission signal including address data to and from the image sensor via the signal line. The transmission signal comprises a start pulse signal, mode data, address data, control data, checksum data, and a signal return period. Therefore, in the load control system described in Patent Document 1, there is a possibility that the signal becomes complicated.

  The present disclosure has been made in view of the above, and an object thereof is to provide a communication device, a slave, a communication system, and a program capable of achieving simplification of a signal.

  A communication apparatus according to an aspect of the present disclosure includes a communication unit and a control unit. The communication unit transmits a synchronization signal to the slave unit. The control unit controls the communication unit. The synchronization signal is a signal for synchronizing the communication device and the slave, and the signal level is periodically switched between at least two values. The control unit performs at least one of a cycle in which the signal level of the synchronization signal is switched between the two values and a duty that is a ratio of a period in which the signal level is one of the two values in the cycle. , Modulate according to the information to be transmitted to the child device.

  The slave according to an aspect of the present disclosure receives the synchronization signal from the communication device.

  A communication system according to an aspect of the present disclosure includes the communication device and the slave.

  A program according to an aspect of the present disclosure causes a computer system to function as the control unit of the communication device.

  The present disclosure has an effect that communication can be simplified.

FIG. 1 is a block diagram of a communication system according to an embodiment of the present disclosure. FIG. 2A is a block diagram of a master provided in the communication system of the same. FIG. 2B is a block diagram of a slave provided in the communication system. FIG. 3 is a diagram showing an example of use of the above communication system. FIG. 4 is a timing chart showing a first operation example of the communication system of the above. FIG. 5 is a flow chart showing a first operation example of the above communication system. FIG. 6 is a timing chart showing a second operation example of the communication system of the above. FIG. 7 is another timing chart showing a second operation example of the communication system same as the above. FIG. 8 is another timing chart showing a second operation example of the communication system same as the above. FIG. 9 is a timing chart showing a third operation example of the communication system of the same as the above. FIG. 10A is a block diagram for explaining a fourth operation example of the communication system same as the above. FIG. 10B is a timing chart showing a fourth operation example of the communication system of the same. FIG. 11 is a timing chart showing an operation example of the communication system according to the modification of the embodiment.

  Each embodiment and modification described below are only examples of the present disclosure, and the present disclosure is not limited to the embodiments and modifications. Even if it is a range other than this embodiment and modification, if it is a range which does not deviate from the technical idea of this indication, various changes are possible according to a design etc.

(1) Outline FIG. 1 shows a block diagram of a communication system 30 of the present embodiment. The communication system 30 of the present embodiment includes a plurality of communication terminals 3 that can communicate with each other. The plurality of communication terminals 3 include one master 1 (communication device) and a plurality of (three in FIG. 1) slaves 2. In the following description, when the master unit 1 and the slave unit 2 are not distinguished from one another, they are referred to as the communication terminal 3. Further, in the case of distinguishing the three handsets 2, the handset 2A, the handset 2B, and the handset 2C are used. In the communication system 30, the number of handsets 2 is not limited to three, and may be one, or two or four or more.

  The base unit 1 and the plurality of handsets 2 are electrically connected by a pair of electric wires 41 and 42. Specifically, the plurality of handsets 2 are wired (multi-drop wiring) to the master 1 via the pair of electric wires 41 and 42. The base unit 1 supplies power to each of the plurality of handsets 2 via the pair of electric wires 41 and 42. The plurality of handsets 2 are electrically connected by a pair of electric wires 41 and 42 by, for example, feed wiring.

  Each of the master unit 1 and the plurality of handsets 2 transmits a signal to the other communication terminal 3 by reducing the voltage between the pair of electric wires 41 and 42. Each of the master unit 1 and the plurality of handsets 2 receives a signal from another communication terminal 3 by monitoring the voltage between the pair of electric wires 41 and 42. That is, the master unit 1 and the slave unit 2 can perform two-way communication via the pair of electric wires 41 and 42.

  The communication system 30 of the present embodiment has a function as a lighting control system that controls the lighting system 80. Each communication terminal 3 has a function as a moving body detection device that detects the presence or absence of a moving body in the detection range. In the present embodiment, a person 9 is assumed as a moving object which is a detection target (see FIG. 3). That is, each communication terminal 3 has a function as a human detection device. Each communication terminal 3 detects the presence or absence of the person 9 in a detection range set in, for example, a house, an office, a store, a school, a hospital or the like. In the present embodiment, each communication terminal 3 particularly detects the presence or absence of a detection target (person 9) that emits infrared light by detecting a change in the light reception intensity of the infrared light. In FIG. 3, only one master unit 1 and one slave unit 2 are illustrated, and the other slave units 2 are omitted.

  The child device 2 detects the presence or absence of the person 9 based on the change in the intensity of infrared light from the detection range 92. That is, the child device 2 moves the person 9 from outside the detection range 92 into the detection range 92 or changes in the light reception intensity of infrared rays caused by the slight movement of the person 9 in the detection range 92 Detect the presence or absence. Here, “micromotion” means, for example, movement of the person 9 without movement, such as shaking of the body due to the breathing of the person 9 and gestures.

  Upon detecting the presence of the person 9 in the detection range 92, the slave 2 outputs a person detection signal to the other communication terminal 3 via the pair of electric wires 41 and 42. The slave unit 2 stops the output of the human detection signal when it does not detect the presence of the person 9 in the detection range 92.

  The parent device 1 detects the presence or absence of the person 9 based on the intensity change of the infrared rays from the detection range 91. That is, the base unit 1 moves the person 9 from outside the detection range 91 into the detection range 91 or changes in the light reception intensity of infrared light caused by the slight movement of the person 9 in the detection range 91 Detect the presence or absence.

  The detection range 92 of the slave 2 and the detection range 91 of the master 1 may be the same, may partially overlap, or may not overlap at all. In the example of FIG. 3, the detection range 92 of the slave 2 and the detection range 91 of the master 1 partially overlap. Hereinafter, a space including the detection ranges 91 and 92 is referred to as a detection space 90.

  The base unit 1 determines whether the state of the detection space 90 is the presence state or the absence state from the presence or absence of the human detection signal from the handset 2 and the detection result of the base unit 1 itself. The “presence state” mentioned here is a state in which the person 9 is present in the detection space 90. The “absent state” is a state in which the person 9 does not exist in the detection space 90.

  The parent device 1 has a function of controlling the operating state of the lighting system 80. The base unit 1 controls the operation state of the illumination system 80 according to the determination result of the state of the detection space 90 (either the existing state or the absent state). The main | base station 1 controls the operation state of the illumination system 80 by notifying the determination result of the state of the detection space 90 to the illumination system 80.

  The lighting system 80 includes a lighting fixture 81 that illuminates the detection space 90 and a controller 82 that controls the lighting fixture 81. If the determination result notified from the parent device 1 is the "presence state", the control device 82 turns on the lighting device 81. On the other hand, if the determination result notified from the parent device 1 is “absent state”, the control device 82 turns off the lighting device 81. The control device 82 includes, for example, a switch that is inserted in the power feeding path to the lighting fixture 81 and turns on / off the lighting of the lighting fixture 81. That is, according to the determination result of the main | base station 1, the operation state (lighting / extinguishing) of the lighting fixture 81 is controlled.

(2) Details The detailed configurations of the communication system 30, the base unit 1, and the handset 2 will be described below.

(2.1) Base Unit First, the configuration of the base unit 1 will be described. As shown in FIG. 2A, the master unit 1 has a light receiving unit 11, a master unit control unit 12 (control unit), a master unit power supply unit 13 (power supply unit), and a master unit communication unit 14 (communication unit). And an output unit 15.

  The parent device side power supply unit 13 is, for example, an AC / DC converter having a full wave rectification circuit and a switching power supply circuit. The parent device side power supply unit 13 converts the AC voltage supplied from the AC power supply 6 into a DC voltage of a first voltage value V1 (first signal level), and outputs the DC voltage between the pair of electric wires 41 and 42. The first voltage value V1 is 15 V, for example. Further, the base unit side power supply unit 13 generates power for operating the base unit 1 from the AC power output from the AC power supply 6. The AC power supply 6 is, for example, a commercial power supply. The parent device side power supply unit 13 is not limited to the AC / DC converter, and may be a battery.

  The base unit side communication unit 14 is electrically connected to the pair of electric wires 41 and 42, and includes a transmission unit 141 and a reception unit 142.

  The transmission unit 141 transmits a voltage signal to the other communication terminal 3 (the handset 2) by reducing the voltage between the pair of electric wires 41 and 42. The transmission unit 141 includes Zener diodes ZD11 and ZD12, and switches SW11 and SW12. The zener diode ZD11 and the switch SW11 are electrically connected in series between the pair of electric wires 41 and 42. The zener diode ZD12 and the switch SW12 are electrically connected in series between the pair of electric wires 41 and 42.

  The voltage value of the Zener voltage (breakdown voltage) of the Zener diode ZD11 is a second voltage value V2 (second signal level). The second voltage value V2 is a value lower than the voltage value (first voltage value V1) of the DC voltage output from the parent device side power supply unit 13. The second voltage value V2 is 12 V, for example.

  The voltage value of the Zener voltage (breakdown voltage) of the Zener diode ZD12 is a third voltage value V3. The third voltage value V3 is lower than the voltage value (first voltage value V1) of the DC voltage output from the parent device side power supply unit 13 and the voltage value (second voltage value V2) of the Zener voltage of the Zener diode ZD12. It is. The third voltage value V3 is 7 V, for example.

  The switches SW11 and SW12 are semiconductor switches such as, for example, MOSFETs (Metal Oxide Semiconductor Field Effect Transistors). The switches SW11 and SW12 are controlled to be turned on / off by the transmission control unit 121 of the master device control unit 12.

  When the switches SW11 and SW12 are both off, the voltage value between the pair of electric wires 41 and 42 becomes the first voltage value V1. When the switch SW11 is on and the switch SW12 is off, current flows through the Zener diode ZD11, and the voltage between the pair of electric wires 41 and 42 becomes the second voltage V2. When the switch SW12 is on, a current flows through the Zener diode ZD12, and the voltage value between the pair of electric wires 41 and 42 becomes the third voltage value V3. Here, it is assumed that the switch SW21 of the handset 2 described later is off.

  That is, the transmission unit 141 transmits a voltage signal by changing (step-down) the voltage between the pair of electric wires 41 and 42 by turning on / off the switches SW11 and SW12. The voltage signal transmitted from the master unit 1 to the other communication terminal 3 (the slave unit 2) has three signal levels (a first voltage value V1, a second voltage value V2, a third voltage value V3) (pair of electric wires 41). , 42) is set.

  The receiving unit 142 receives the voltage signal from the other communication terminal 3 (the handset 2) by detecting the voltage between the pair of electric wires 41 and 42. The receiving unit 142 includes a plurality of (two in FIG. 2) resistors R11 and R12. The resistor R11 and the resistor R12 are electrically connected in series between the pair of electric wires 41 and 42. The receiving unit 142 outputs a value obtained by dividing the voltage between the pair of electric wires 41 and 42 by the resistors R11 and R12 to the reception control unit 122 of the parent device control unit 12.

  The light receiving unit 11 includes a light receiving element 111 and a processing circuit 112.

  The light receiving element 111 is a pyroelectric element (infrared light receiving element). The light receiving element 111 outputs a signal (electric signal) according to the change in the light receiving intensity of the infrared light from the detection range 91.

  The processing circuit 112 is a circuit that performs signal processing of the electrical signal output from the light receiving element 111. In the present embodiment, as an example, the processing circuit 112 converts the current signal output from the light receiving element 111 into a voltage signal, amplifies the voltage signal, and amplifies the amplified analog signal (voltage signal). Has an A / D conversion function to convert D into a digital signal. Therefore, the light receiving unit 11 outputs a digital signal corresponding to the electrical signal output from the light receiving element 111 to the detection unit 123 of the master control unit 12 as an output signal S1.

  The light receiving unit 11 is used in combination with the optical system 16 (see FIG. 3). The optical system 16 is composed of a lens or a mirror, or a combination of these, and condenses infrared light from the detection range 91 on the light receiving element 111. In the present embodiment, the light receiving unit 11 is housed in one housing 17 (see FIG. 3) together with the base unit power supply unit 13, the base unit communication unit 14, the base unit control unit 12, and the like. As shown in FIG. 3, for example, the main unit 1 including the light receiving unit 11 is installed on a ceiling of a living room of a house, and receives infrared light from a detection range 91 set in the living room.

  The parent device control unit 12 includes a transmission control unit 121, a reception control unit 122, a detection unit 123, and a determination unit 124. The main control unit 12 mainly includes a computer such as a microcomputer. The parent device control unit 12 implements the functions of the above-described units by executing the program recorded in the memory of the microcomputer by the processor of the microcomputer. The program may be pre-recorded in a memory, may be provided through a telecommunication line such as the Internet, or may be provided by being recorded in a recording medium such as a memory card.

  The transmission control unit 121 controls the on / off of the switches SW11 and SW12 of the transmission unit 141 to transmit a voltage signal from the base-unit communication unit 14 to the other communication terminal 3 (child unit 2). The transmission control unit 121 individually controls on / off of the switches SW11 and SW12 by individually outputting a control signal for turning on / off the switches SW11 and SW12. The voltage signal that the base unit side communication unit 14 transmits to the other communication terminal 3 (the handset 2) will be described in detail in the section of “(3) Operation example” described later.

  The reception control unit 122 detects the voltage value of the voltage between the pair of electric wires 41 and 42 by acquiring the resistance division value of the voltage between the pair of electric wires 41 and 42 by the reception unit 142 in a predetermined sampling cycle. ing. Similar to the parent device 1, the child device 2 is configured to transmit a voltage signal that changes (steps down) the voltage between the pair of electric wires 41 and 42. The reception control unit 122 receives a voltage signal from the handset 2 by detecting a change in voltage value between the pair of electric wires 41 and 42. The reception control unit 122 receives the voltage signal from the child device 2 to receive the detection result of the person 9 in the detection range 92 by the child device 2.

  The detection unit 123 determines whether or not the person 9 is present in the detection range 91 based on the output signal S1 from the light receiving unit 11 (processing circuit 112). The operation mode of the detection unit 123 includes an approach detection mode and a stay detection mode.

  The entry detection mode is an operation mode for detecting the presence or absence of the entry of the person 9 into the detection range 91. The detection unit 123 operates in the entry detection mode when the person 9 is not present in the detection space 90 (a space including the detection ranges 91 and 92) and the lighting fixture 81 is turned off.

  The stay detection mode is an operation mode for detecting the presence or absence of the person 9 leaving the detection range 91. The detection unit 123 operates in the stay detection mode when the person 9 is present in the detection space 90 (a space including the detection ranges 91 and 92) and the lighting fixture 81 is on.

  In the entry detection mode, the detection unit 123 compares the amplitude A1 of the output signal S1 with the first detection threshold Vth11 (see FIG. 9). If the amplitude A1 of the output signal S1 is equal to or greater than the first detection threshold Vth11, the detection unit 123 determines that the person 9 has entered the detection range 91 (the person 9 is present in the detection range 91). Then, the detection unit 123 notifies the determination unit 124 of the detection result. The transmission control unit 121 causes the transmission unit 141 to transmit an entry detection signal when the detection unit 123 detects the presence of the person 9 in the entry detection mode. In addition, when at least one of the plurality of communication terminals 3 (the base unit 1 and the handset 2) detects the entry of the person 9 into the corresponding detection range, the detection unit 123 stays in the operation mode from the entry detection mode. Switch to detection mode.

  In the stay detection mode, the detection unit 123 compares the amplitude A1 of the output signal S1 with the second detection threshold Vth12. The detection unit 123 determines whether the duration of the state in which the amplitude A1 of the output signal S1 is lower than the second detection threshold Vth12 exceeds the stay determination time. When the duration of the state in which the amplitude A1 of the output signal S1 is lower than the second detection threshold Vth12 exceeds the stay determination time, the detection unit 123 has left the person 9 from the detection range 91 (the detection range 91 corresponds to the person 9). Is determined to be absent). In other words, the detection unit 123 detects that the person 9 stays in the detection range 91 during the stay determination time after the amplitude A1 of the output signal S1 lastly exceeds the second detection threshold Vth12 (a person in the detection range 91 It is determined that 9 exists. The count value of the stay determination time is reset each time the amplitude A1 of the output signal S1 exceeds the second detection threshold Vth12.

  The value of the stay determination time is variable, and is set by the user to, for example, one minute, three minutes, five minutes, ten minutes, or the like. Then, the detection unit 123 notifies the determination unit 124 of the detection result. When the detection unit 123 detects the presence of the person 9 in the stay determination mode, the transmission control unit 121 causes the transmission unit 141 to transmit a stay detection signal during the stay determination time. In addition, when the detection unit 123 determines that all of the plurality of communication terminals 3 (the base unit 1 and the handset 2) are absent in the corresponding detection range, the operation mode is detected as an entry from the stay detection mode. Switch to mode. In addition, the numerical value of said stay determination time is an example, Comprising: It does not restrict to said numerical value.

  In the present embodiment, the first detection threshold Vth11 and the second detection threshold Vth12 have the same value, but may have different values.

  The determination unit 124 determines the state of the detection space 90 (the space including the detection ranges 91 and 92) based on the detection result from the detection unit 123 and the detection results of the person 9 by the plurality of handsets 2 To determine if it is or not. When at least one of the detection unit 123 and the plurality of handsets 2 detects the entry of the person 9, the determination unit 124 determines that the state of the detection space 90 is in the existing state during a predetermined entry determination time. Do. The entry determination time is variable, for example, between 1 minute and 30 minutes, and is set by the user. When all of the detection unit 123 and the plurality of handsets 2 detect the absence (exit) of the person 9 after the entry determination time has elapsed, the determination unit 124 determines that the state of the detection space 90 is the absence state, judge. That is, the determination unit 124 determines whether the state of the detection space 90 is the presence state or the absence state from the detection results of the entry / exit of the person 9 in all the plurality of communication terminals 3. The determination unit 124 notifies the output unit 15 of the determination result as to whether the detection space 90 is in the presence state or in the absence state.

  The output unit 15 is a communication interface capable of transmitting a signal to the control device 82 of the lighting system 80. The output unit 15 outputs the determination result of the determination unit 124 to the control device 82. Specifically, the output unit 15 outputs a determination signal indicating the determination result of the determination unit 124 to the control device 82. When the determination result by the determination unit 124 is “an absent state”, the output unit 15 outputs a determination signal indicating “an absent state”. When the determination result by the determination unit 124 is the “presence state”, the output unit 15 outputs a determination signal indicating the “presence state”. The output unit 15 serially outputs, for example, a determination signal indicating the determination result of the determination unit 124 to the control device 82. Specifically, the output unit 15 outputs a determination signal including the start bit, the determination result, and the stop bit.

  The control device 82 is configured to control the lighting / extinguishing of the lighting fixture 81 based on the determination signal from the parent device 1. The controller 82 mainly includes a computer such as a microcomputer. The control device 82 implements the following various functions by executing the program stored in the memory of the microcomputer by the processor of the microcomputer. The program may be pre-recorded in a memory, may be provided through a telecommunication line such as the Internet, or may be provided by being recorded in a recording medium such as a memory card.

  When the control device 82 receives the determination signal indicating the detection result of the “absent state” from the parent device 1, the control device 82 determines that the state of the detection space 90 is the “absent state”, and turns off the lighting fixture 81. On the other hand, when the control device 82 receives a determination signal indicating the detection result of the "presence state" from the parent device 1, the control device 82 determines that the state of the detection space 90 is the "presence state", and turns on the lighting fixture 81.

(2.2) Mobile Unit Next, the configuration of the mobile unit 2 will be described. As shown in FIG. 2B, the slave unit 2 includes the light receiving unit 21, the slave unit-side control unit 22, the diode bridge (DB) 23, the slave unit-side power supply unit 24, and the slave unit-side communication unit 25. Have.

  The diode bridge 23 is a full bridge circuit including a plurality of diodes. The diode bridge 23 has an input end electrically connected to the pair of electric wires 41 and 42, and an output end electrically connected to the slave unit side power supply unit 24 and the slave unit side communication unit 25.

  The slave unit side power supply unit 24 is, for example, a DC / DC converter. The slave unit-side power supply unit 24 generates power for operating the slave unit 2 from the DC power supplied from the master unit-side power supply unit 13 of the master unit 1 via the pair of electric wires 41 and 42.

  The slave unit side communication unit 25 is electrically connected to the pair of electric wires 41 and 42 via the diode bridge 23, and includes a transmission unit 251 and a reception unit 252.

  The transmitting unit 251 reduces the voltage between the pair of electric wires 41 and 42 to transmit a voltage signal to the other communication terminal 3 (master unit 1 and slave unit 2). The transmission unit 251 includes a Zener diode ZD21 and a switch SW21. The zener diode ZD21 and the switch SW21 are electrically connected in series between the pair of electric wires 41 and 42. Specifically, a series circuit of the Zener diode ZD21 and the switch SW21 is electrically connected between a pair of output terminals of the diode bridge 23.

  The voltage value of the Zener voltage (breakdown voltage) of the Zener diode ZD21 is a third voltage value V3. That is, the voltage value of the Zener voltage of the Zener diode ZD21 is the same as the voltage value (third voltage value V3) of the Zener voltage of the Zener diode ZD12 of the transmission unit 141 in the parent device 1. The same as mentioned here includes not only the perfect match of the voltage value of the Zener voltage but also the case where the error is within the allowable range.

  The switch SW21 is, for example, a semiconductor switch such as a MOSFET. The on / off of the switch SW21 is controlled by the transmission control unit 221 of the slave unit control unit 22.

  When the switch SW21 is off, the voltage value between the pair of electric wires 41 and 42 becomes the first voltage value V1. When the switch SW21 is on, a current flows through the Zener diode ZD21, and the voltage between the pair of electric wires 41 and 42 becomes the third voltage value V3. Here, it is assumed that the switches SW11 and SW12 of the parent device 1 and the switch SW21 of the other handset 2 are off.

  That is, the transmission unit 251 transmits a voltage signal that changes (steps down) the voltage between the pair of electric wires 41 and 42 by turning on / off the switch SW21. The voltage signal that handset 2 transmits to the other communication terminal 3 (master 1, handset 2) has two levels (first voltage value V1, third voltage value V3) signal levels (pair of electric wires 41, 42). Voltage value) is set.

  The receiving unit 252 receives the voltage signal from the other communication terminal 3 (the base unit 1 and the handset 2) by detecting the voltage between the pair of electric wires 41 and 42. The receiving unit 252 includes a plurality of (two in FIG. 2) resistors R21 and R22. Between a pair of electric wires 41 and 42, resistance R21 and resistance R22 are electrically connected in series. The receiving unit 252 outputs a value obtained by dividing the voltage between the pair of electric wires 41 and 42 by the resistors R21 and R22 to the reception control unit 222 of the slave control unit 22.

  The light receiving unit 21 includes a light receiving element 211 and a processing circuit 212.

  The light receiving element 211 is a pyroelectric element (infrared light receiving element). The light receiving element 211 outputs a signal (electric signal) according to the change in the light receiving intensity of the infrared light from the detection range 92.

  The processing circuit 212 is a circuit that performs signal processing of the electrical signal output from the light receiving element 211. In this embodiment, as an example, the processing circuit 212 converts the current signal output from the light receiving element 211 into a voltage signal, amplifies the voltage signal, and amplifies the amplified analog signal (voltage signal). Has an A / D conversion function to convert D into a digital signal. Therefore, the light receiving unit 21 outputs a digital signal corresponding to the electric signal output from the light receiving element 211 to the detecting unit 223 of the slave-side control unit 22 as an output signal S2.

  The light receiving unit 21 is used in combination with the optical system 26 (see FIG. 3). The optical system 26 is made of a lens or a mirror, or a combination of these, and condenses infrared light from the detection range 92 onto the light receiving element 211. In the present embodiment, the light receiving unit 21 is housed in one casing 27 (see FIG. 3) together with the slave unit side power supply unit 24, the slave unit side communication unit 25, the slave unit side control unit 22 and the like. As shown in FIG. 3, for example, the handset 2 provided with the light receiving unit 21 is installed on a ceiling of a living room of a house, and receives infrared light from a detection range 92 set in the living room.

  The slave unit control unit 22 includes a transmission control unit 221, a reception control unit 222, and a detection unit 223. The slave unit control unit 22 mainly includes a computer such as a microcomputer. The slave unit control unit 22 implements the functions of the above-described units by executing the program stored in the memory of the microcomputer by the processor of the microcomputer. The program may be pre-recorded in a memory, may be provided through a telecommunication line such as the Internet, or may be provided by being recorded in a recording medium such as a memory card.

  The transmission control unit 221 controls the on / off of the switch SW 21 of the transmission unit 251 to transmit a voltage signal from the handset communication unit 25 to the other communication terminal 3 (master unit 1, handset 2). The transmission control unit 221 controls the on / off of the switch SW <b> 21 by outputting a control signal to turn on / off the switch SW <b> 21. The voltage signals that the handset communication unit 25 transmits to the other communication terminals 3 (the base unit 1 and handset 2) will be described in detail in the section "(3) Operation example" described later.

  The reception control unit 222 detects the voltage value of the voltage between the pair of electric wires 41 and 42 by acquiring the resistance division value of the voltage between the pair of electric wires 41 and 42 by the reception unit 252 at a predetermined sampling cycle. ing. As described above, each communication terminal 3 (the base unit 1 and the handset 2) is configured to transmit a voltage signal that changes (steps down) the voltage between the pair of electric wires 41 and 42. The reception control unit 222 receives a voltage signal from another communication terminal 3 (the base unit 1 and the handset 2) by detecting a change in voltage value between the pair of electric wires 41 and 42.

  The detection unit 223 determines whether or not the person 9 is present in the detection range 92 based on the output signal S2 from the light receiving unit 21 (processing circuit 212). The operation mode of the detection unit 223 includes an approach detection mode and a stay detection mode.

  The entry detection mode is an operation mode for detecting the presence or absence of the entry of the person 9 into the detection range 92. The detection unit 223 operates in the entry detection mode when the person 9 is not present in the detection space 90 (a space including the detection ranges 91 and 92) and the lighting fixture 81 is turned off.

  The stay detection mode is an operation mode for detecting the presence or absence of the person 9 leaving the detection range 92. The detection unit 223 operates in the stay detection mode when the person 9 is present in the detection space 90 (a space including the detection ranges 91 and 92) and the lighting fixture 81 is on.

  In the entry detection mode, the detection unit 223 compares the amplitude A2 of the output signal S2 with the first detection threshold Vth21 (see FIGS. 6 and 7). If the amplitude A2 of the output signal S2 is equal to or greater than the first detection threshold Vth21, the detection unit 223 determines that the person 9 has entered the detection range 92 (the person 9 is present in the detection range 92). The transmission control unit 221 causes the transmission unit 251 to transmit an entrance detection signal when the detection unit 223 detects the presence of the person 9 in the entrance detection mode. In addition, the detection unit 223 receives the determination result of the determination unit 124 from the parent device 1 so that at least one of the plurality of communication terminals 3 (the parent device 1 and the child device 2) can receive the person 9 to the corresponding detection range. When it detects the approach of, the operation mode is switched from the approach detection mode to the stay detection mode.

  In the stay detection mode, the detection unit 223 compares the amplitude A2 of the output signal S2 with the second detection threshold Vth22. The detection unit 223 determines whether or not the duration of the state in which the amplitude A2 of the output signal S2 is less than the second detection threshold Vth22 exceeds the stay determination time. When the state in which the amplitude A2 of the output signal S2 is lower than the second detection threshold Vth22 continues the stay determination time, the detection unit 223 withdraws the person 9 from the detection range 92 (the person 9 does not exist in the detection range 92) It is determined that In other words, the detection unit 223 detects that the person 9 stays in the detection range 92 during the stay determination time after the amplitude A2 of the output signal S2 lastly exceeds the second detection threshold Vth22 (a person in the detection range 92 It is determined that 9 exists. The count value of the stay determination time is reset each time the amplitude A2 of the output signal S2 exceeds the second detection threshold Vth22. The value of the stay determination time is variable, and is set to, for example, 1 minute, 3 minutes, 5 minutes, 10 minutes, etc. by the main unit 1. The setting of the stay determination time in the slave unit 2 will be described in the section of “(3) Operation example” described later. When the detection unit 223 detects the presence of the person 9 in the stay determination mode, the transmission control unit 221 causes the transmission unit 251 to transmit a stay detection signal during the stay determination time.

  If the detection unit 223 determines that all of the plurality of communication terminals 3 (the base unit 1 and the handset 2) are absent from the corresponding detection range, the operation mode changes from the stay detection mode to the entry detection mode. Switch.

  In the present embodiment, the first detection threshold Vth21 and the second detection threshold Vth22 have the same value, but may have different values. Further, the first detection threshold Vth21 in the slave unit 2 may be the same value as the first detection threshold Vth11 in the master unit 1, or may be a different value. In addition, the second detection threshold Vth22 in the slave unit 2 may be the same value as the second detection threshold Vth12 in the master unit 1, or may be a different value.

(3) Operation Example Next, an operation example of the communication system 30 of the present embodiment will be described.

(3.1) First Operation Example First, a first operation example of the communication system 30 will be described with reference to FIG.

  In the communication system 30 of the present embodiment, each communication terminal 3 (master unit 1, slave unit 2) is configured to perform synchronous communication. In order for each communication terminal 3 to synchronize, master device 1 transmits a synchronization signal to slave device 2. The synchronization signal is a signal whose signal level periodically switches between two values. Specifically, in the synchronization signal, the voltage value of the voltage between the pair of electric wires 41 and 42 is a signal level, and the first voltage value V1 (first signal level) and the second voltage value V2 (binary values) And periodically change with the second signal level). The synchronization signal periodically generates a pulse in which the voltage value of the voltage between the pair of electric wires 41 and 42 is the second voltage value V2.

  The transmission control unit 121 of the parent device 1 changes the voltage value between the pair of electric wires 41 and 42 from the first voltage value V1 to the second voltage value V2 by periodically turning on the switch SW11. That is, the time T2 during which the switch SW11 is on is the pulse width of the synchronization signal. This time T2 is 50 ms, for example.

  The reception control unit 222 of the slave 2 synchronizes using the change from the first voltage value V1 to the second voltage value V2 as a trigger of the voltage value of the voltage between the pair of electric wires 41 and 42.

  The transmission control unit 121 modulates the cycle T 1 of the synchronization signal according to the information to be transmitted to the slave 2. The cycle T1 is a cycle in which the voltage value of the voltage between the pair of electric wires 41 and 42 is switched between the first voltage value V1 and the second voltage value V2. That is, the transmission control unit 121 sets the period T1 of the synchronization signal to a time length corresponding to the information to be transmitted to the slave 2. In the present embodiment, the information transmitted to the slave 2 is setting information and lighting information. The setting information indicates the value (for example, 1 minute, 3 minutes, 5 minutes, 10 minutes, etc.) of the stay determination time set in the handset 2. The lighting information indicates whether the lighting fixture 81 is on or off. A plurality of combinations of setting information (stay determination time) and lighting information (lighting state, extinguishing state) are associated one-to-one with a plurality of time lengths of cycle T1. The plurality of time lengths of the cycle T1 corresponding to the plurality of combinations of setting information and lighting information are different from each other. Data in which a plurality of combinations of setting information and lighting information are associated with a plurality of time lengths of the cycle T1 is stored in the storage unit 120. The storage unit 120 is a semiconductor memory such as a read only memory (ROM) or an electrically erasable programmable read only memory (EEPROM).

  The transmission control unit 121 determines the time length of the cycle T1 based on the combination of the setting information and the lighting information.

  Specifically, as shown in FIG. 5, the transmission control unit 121 acquires setting information (S11). The setting information is registered (stored) in advance in, for example, the memory of the parent device 1. The registration of setting information in the memory of the parent device 1 is performed by, for example, a setting device connected to the parent device 1 by wire or wirelessly. The transmission control unit 121 accesses the memory, and acquires information (setting information) indicating whether the stay determination time set in the handset 2 is one minute, three minutes, five minutes, or ten minutes, for example. The transmission control unit 121 may be configured to acquire setting information from a dip switch provided in the parent device 1.

  Next, the transmission control unit 121 acquires lighting information (S12). The transmission control unit 121 acquires lighting information by acquiring the determination result from the determination unit 124. As described above, the control device 82 turns off the luminaire 81 if the determination result of the determination unit 124 is "absent state", and turns on the luminaire 81 if the determination result of the determination unit 124 is "presence state" Let That is, the determination result of the determination unit 124 corresponds to the state of the lighting fixture 81. The transmission control unit 121 determines that the lighting fixture 81 is on if the determination result of the determination unit 124 is the "presence state", and if the determination result of the determination unit 124 is the "not present state" It is determined that the light is off. As described above, the transmission control unit 121 acquires the determination result of the determination unit 124 to acquire information (lighting information) indicating whether the lighting apparatus 81 is on or off. The transmission control unit 121 may be configured to obtain lighting information from the control device 82.

  Next, the transmission control unit 121 determines the time length of the cycle T1 of the synchronization signal based on the acquired setting information and lighting information (S13). The transmission control unit 121 accesses the storage unit 120, and acquires data with a time length of period T1 corresponding to the combination of the acquired setting information and lighting information.

  The transmission control unit 121 causes the transmission unit 141 to transmit the synchronization signal so that the time length of the cycle T1 of the synchronization signal becomes the time length determined (acquired) in step S13 (S14). When a change occurs in the setting information (S15: Yes), the transmission control unit 121 reacquires the setting information (S11). When a change occurs in the lighting information (S16: Yes), the transmission control unit 121 reacquires the lighting information (S12). When the setting information and the lighting information are not changed (S15: No, S16: No), the transmission control unit 121 continues the transmission of the synchronization signal while maintaining the time length of the cycle T1 (S14).

  The reception control unit 222 of the slave 2 receives the setting information and the lighting information from the master 1 by measuring the time length of the cycle T1 of the synchronization signal. Specifically, after the voltage value of the voltage between the pair of electric wires 41 and 42 is changed from the first voltage value V1 to the second voltage value V2, the reception control unit 222 then operates between the pair of electric wires 41 and 42 next. The time until the voltage value of the voltage changes from the first voltage value V1 to the second voltage value V2 is measured. Further, similarly to the base unit 1, the handset 2 includes the storage unit 220 that stores data in which a plurality of combinations of setting information and lighting information are associated with a plurality of time lengths of the cycle T1. . The storage unit 220 is, for example, a semiconductor memory such as a read only memory (ROM) or an electrically erasable programmable read only memory (EEPROM). The reception control unit 222 accesses the storage unit 220, and acquires setting information and lighting information corresponding to the measured time length of the cycle T1 of the synchronization signal.

  The detection unit 223 sets the value of the stay determination time used in the stay detection mode to the value of the stay determination time indicated by the setting information acquired by the reception control unit 222.

  If the lighting information acquired by the reception control unit 222 indicates that the lighting fixture 81 is on, the detection unit 223 sets the operation mode to stay detection mode, and if the lighting fixture 81 is on, the operation mode is entry detection mode Make it

  As described above, in the communication system 30 of the present embodiment, the time length of the cycle T1 of the synchronization signal transmitted by the master unit 1 corresponds to the information transmitted from the master unit 1 to the slave unit 2. Therefore, the signal between the master unit 1 and the slave unit 2 can be simplified.

(3.2) Second Operation Example Next, a second operation example of the communication system 30 will be described with reference to FIG. 6 and FIG.

  Here, it is assumed that the luminaire 81 is in the extinguishing state and the handset 2A among the plurality of communication terminals 3 (the base unit 1 and the handset 2) detects the presence of the person 9 in the entry detection mode.

  The transmission control unit 121 of the parent device 1 causes the transmission unit 141 to transmit a synchronization signal in which the time length of the cycle T1 is T11. The time length T11 indicates that the stay determination time T5 (see FIG. 7) which is the setting information is 3 minutes, and the lighting state of the lighting fixture 81 which is the lighting information is in the extinguishing state. The slave unit 2A sets the stay determination time T5 to 3 minutes by measuring the time length T11 of the cycle T1 of the synchronization signal, and sets the operation mode to the entry detection mode.

  At time t1, the amplitude A2 of the output signal S2 becomes equal to or greater than the first detection threshold Vth21, and the detection unit 223 of the handset 2A determines that the person 9 has entered the detection range 92 (the person 9 is present in the detection range 92) Do. The detection unit 223 switches the operation mode from the entry detection mode to the stay detection mode by detecting the presence of the person 9 in the entry detection mode.

  Further, the transmission control unit 221 of the handset 2A causes the transmission unit 251 to transmit an entry detection signal when the detection unit 223 detects the presence of the person 9 in the entry detection mode. Specifically, the transmission control unit 221 transmits an entrance detection signal in one time slot Ts set based on the synchronization signal.

  The entry detection signal is a pulse signal (voltage signal) in which the voltage value of the voltage between the pair of electric wires 41 and 42 changes from the first voltage value V1 to the third voltage value V3. The pulse width T41 of the approach detection signal is a value longer than a predetermined threshold time. The pulse width T41 of the entry detection signal is, for example, 100 ms. The stay detection signal described later is a pulse signal (voltage signal) in which the voltage value of the voltage between the pair of electric wires 41 and 42 changes from the first voltage value V1 to the third voltage value V3 as in the case of the entry detection signal. The pulse width T42 of the stay detection signal is a value shorter than a predetermined threshold time. The pulse width T42 of the stay detection signal is, for example, 20 ms.

  The time slot Ts is a predetermined period starting from time T3 after the voltage value of the voltage between the pair of electric wires 41 and 42 changes from the first voltage value V1 to the second voltage value V2 by the synchronization signal. One time slot Ts occurs in one cycle of the synchronization signal. The reception control unit 122 of the base unit 1 receives an approach detection signal and a stay detection signal in the time slot Ts. Specifically, when the voltage value of the voltage between the pair of electric wires 41 and 42 changes from the first voltage value V1 to the third voltage value V3 in the time slot Ts, the reception control unit 122 performs the pair of electric wires 41, The time when the voltage value of the voltage between 42 is the third voltage value V3 is measured. If the measured time is longer than the threshold time, the reception control unit 122 determines that the data signal transmitted from the handset 2 is an entry detection signal. Further, when the measured time is shorter than the threshold time, the reception control unit 122 determines that the data signal transmitted from the handset 2 is a stay detection signal.

  The transmission control unit 221 of the slave unit 2A performs transmission by turning on the switch SW21 for a time T41 from the start point of the time slot Ts in the time slot Ts after the detection unit 223 detects the presence of the person 9 in the entry detection mode. An entry detection signal is transmitted from the unit 251.

  When the reception control unit 122 receives the entry detection signal, the determination unit 124 of the base unit 1 determines that the state of the detection space 90 is in the existing state during a predetermined entry determination time. The determination unit 124 outputs the determination result to the control device 82 via the output unit 15. The control device 82 lights the lighting fixture 81 based on the determination result of the determination unit 124 (at time t2).

  Based on the determination result of the determination unit 124, the detection unit 123 of the base unit 1 switches the operation mode from the entry detection mode to the stay detection mode.

  Transmission control section 121 of base unit 1 changes the time length of period T1 of the synchronization signal from T11 to T12 based on the determination result of determination section 124. The time length T12 indicates that the stay determination time T5 which is setting information is 3 minutes, and the lighting state of the lighting fixture 81 which is lighting information is on. The slave units 2B and 2C switch the operation mode of the detection unit 223 from the entry detection mode to the stay detection mode by measuring the time length T12 of the cycle T1 of the synchronization signal.

  After time t1, the amplitude A2 of the output signal S2 becomes equal to or greater than the second detection threshold Vth22, and the detection unit 223 of the handset 2A determines that the person 9 is staying in the detection range 92. When the detection unit 223 detects the presence of the person 9 in the stay detection mode, the transmission control unit 221 detects stay from the transmission unit 251 by turning on the switch SW 21 for only the time T42 from the start point of the time slot Ts in the time slot Ts. Send a signal.

  If the reception control unit 122 receives the stay detection signal after the entry determination time after the reception control unit 122 receives the entry detection signal, the determination unit 124 of the parent device 1 has the state of the detection space 90 It determines that it is a state. While the reception control unit 122 receives the stay detection signal, the determination unit 124 determines that the state of the detection space 90 is in the existing state. That is, lighting of the lighting fixture 81 is continued while the reception control unit 122 receives the stay detection signal after the entry determination time.

  The detection unit 223 determines that the person 9 is staying in the detection range 92 during a stay determination time T5 from time t3 when the amplitude A2 of the output signal S2 finally exceeds the second detection threshold Vth22. The transmission control unit 221 continues transmission of the stay detection signal during the stay determination time T5 (see FIG. 7). The detection unit 223 detects that the person 9 has left the detection range 92 at time t4 when the duration of the state in which the amplitude A2 of the output signal S2 is lower than the second detection threshold Vth22 exceeds the stay determination time T5 (detection range It is determined that the person 9 does not exist in 92). When the detection unit 223 determines that the person 9 is not present in the detection range 92, the transmission control unit 221 stops the transmission of the stay detection signal.

  The reception control unit 122 of the base unit 1 determines that the transmission of the stay detection signal is stopped when the state in which the stay detection signal can not be received in the time slot Ts continues for a predetermined time (for example, 5 seconds). When the reception control unit 122 determines that the transmission of the stay detection signal is stopped, the determination unit 124 determines that the state of the detection space 90 is an absent state. The determination unit 124 outputs the determination result to the control device 82 via the output unit 15. The control device 82 turns off the lighting device 81 based on the determination result of the determination unit 124 (at time t5).

  Transmission control section 121 of base unit 1 changes the time length of period T1 of the synchronization signal from T12 to T11 based on the determination result of determination section 124. The detection unit 223 of the slaves 2A, 2B, 2C switches the operation mode from the stay detection mode to the entry detection mode by measuring the time length T11 of the cycle T1 of the synchronization signal. Further, based on the determination result of the determination unit 124, the detection unit 123 of the parent device 1 switches the operation mode from the stay detection mode to the entry detection mode.

  In the operation example described above, although the case where the handset 2A of the three handsets 2 detects the presence of the person 9 has been described, the same operation is performed when the handsets 2B and 2C detect the presence of the person 9 To be done.

  The time slot Ts is common to the slaves 2A, 2B and 2C. That is, the slaves 2A, 2B, 2C transmit an approach detection signal and a stay detection signal in one common time slot Ts. For example, it is assumed that the detection unit 223 of each of the slaves 2A, 2B, and 2C detects the presence of the person 9 in the stay detection mode.

  As shown in FIG. 8, in each of the slaves 2A and 2B, each of the detection units 223 detects the presence of the person 9 in the stay detection mode. The transmission control unit 221 of each of the slave units 2A and 2B transmits a stay detection signal by turning on the switch SW21 for a time T42 from the start point of the time slot Ts in the time slot Ts set based on the synchronization signal. That is, the switch SW21 of the handset 2A and the switch SW21 of the handset 2B are turned on at the same timing.

  Further, in the example illustrated in FIG. 8, the detection unit 223 of the handset 2C detects the presence of the person 9 in the stay detection mode at a timing after the handsets 2A and 2B. Similar to the slave units 2A and 2B, the transmission control unit 221 of the slave unit 2C transmits a stay detection signal by turning on the switch SW21 for a time T42 from the start point of the time slot Ts. That is, the switches SW21 of the slaves 2A, 2B, 2C are turned on at the same timing.

  As described above, in the present embodiment, one common time slot Ts is allocated to the plurality of handsets 2. Therefore, it is not necessary to assign different time slots to a plurality of handsets 2, and even if the number of handsets 2 is increased, it is possible to suppress the redundancy of the period T1 of the synchronization signal.

  Further, even when each of the plurality of handsets 2 detects the presence of the person 9, the plurality of handsets 2 transmit the stay detection signal at the same timing. Therefore, the period in which the voltage between the pair of wires 41 and 42 is the third voltage value V3 lower than the first voltage value V1 and the second voltage value V2 is limited, and the current flowing through the pair of wires 41 and 42 The average value of the current consumption of 2) can be suppressed.

(3.3) Third Operation Example Next, a third operation example of the communication system 30 will be described with reference to FIG.

  Here, it is assumed that the lighting apparatus 81 is turned off and the base unit 1 detects the presence of the person 9 in the entry detection mode among the plurality of communication terminals 3 (the base unit 1 and the handset 2).

  The transmission control unit 121 of the parent device 1 causes the transmission unit 141 to transmit a synchronization signal whose period T1 has a time length of T11, since the determination result of the determination unit 124 is "absent state".

  At time t6, the amplitude A1 of the output signal S1 is equal to or greater than the first detection threshold Vth11, and the detection unit 123 of the parent device 1 determines that the person 9 has entered the detection range 91 (the person 9 is present in the detection range 91) Do. The determination unit 124 determines that the state of the detection space 90 is in the existing state during a predetermined entry determination time because the detection unit 123 detects the entry of the person 9. The determination unit 124 outputs the determination result to the control device 82 via the output unit 15. The control device 82 lights the lighting fixture 81 based on the determination result of the determination unit 124. Further, the detection unit 123 switches the operation mode from the entry detection mode to the stay detection mode by detecting the presence of the person 9 in the entry detection mode.

  The transmission control unit 121 changes the time length of the period T1 of the synchronization signal from T11 to T12 based on the determination result of the determination unit 124.

  In addition, the transmission control unit 121 turns on the switch SW12 for only the time T41 from the start point of the time slot Ts in the time slot Ts after the detection unit 123 detects the presence of the person 9 in the entry detection mode. Send an entry detection signal from.

  After time t6, the amplitude A1 of the output signal S1 becomes equal to or greater than the second detection threshold Vth12, and the detection unit 123 of the base unit 1 determines that the person 9 stays in the detection range 91. When the detection unit 123 detects the presence of the person 9 in the stay detection mode, the transmission control unit 121 detects stay from the transmission unit 251 by turning on the switch SW 12 for only time T42 from the start point of the time slot Ts in time slot Ts. Send a signal.

  The reception control unit 222 of the slave 2 receives an entry detection signal and a stay detection signal from the master 1 in the time slot Ts.

  As described above, in the communication system 30 of the present embodiment, when each communication terminal 3 (the base unit 1 and the handset 2) detects the presence of the person 9, the entry detection signal or the stay detection signal is transmitted. Thus, when at least one communication terminal 3 among the plurality of communication terminals 3 (the base unit 1 and the handset 2) detects the presence of the person 9, the person 9 exists in each of the communication terminals 3 Information can be shared. In the example described above, the detection unit 123 of the base unit 1 and the detection unit 223 of the handset 2 have determined the operation mode based on the determination result (lighting information) of the determination unit 124 of the base unit 1. Not exclusively. When the main unit 1 transmits or receives a stay detection signal, the detection unit 123 of the main unit 1 sets the operation mode to be a stay detection mode, and when neither a transmission nor a reception of a stay detection signal, an operation mode is detected It may be configured to be in a mode. Similarly, when the handset 2 transmits or receives a stay detection signal, the detection unit 223 of the handset 2 sets the operation mode to the stay detection mode, and neither transmits nor receives a stay detection signal, the operation mode. May be configured to be the entry detection mode.

  Further, in the communication system 30 of the present embodiment, in the time slot Ts set based on the synchronization signal transmitted by the master unit 1, the master unit 1 itself transmits the entry detection signal and the stay detection signal as well as the slave unit 2 Do. That is, in the communication system 30 of the present embodiment, one common time slot Ts is allocated to a plurality of communication terminals 3 (base unit 1 and handset 2), and each communication terminal 3 (base unit 1, The slave 2) transmits and receives signals in a common time slot Ts. Therefore, it is not necessary to assign different time slots to a plurality of communication terminals 3, and even when the number of communication terminals 3 is increased, it is possible to suppress the redundancy of the period T1 of the synchronization signal.

(3.4) Fourth Operation Example Next, a fourth operation example of the communication system 30 will be described with reference to FIGS. 10A and 10B. In FIG. 10A, only one master unit 1 and one slave unit 2 among the plurality of communication terminals 3 are illustrated.

  Each communication terminal 3 (master unit 1, slave unit 2) is configured to shift to the inspection mode by an inspection signal transmitted from an inspection device electrically connected to the pair of electric wires 41 and 42. The inspection signal is a voltage signal in which the voltage value of the voltage between the pair of electric wires 41 and 42 alternately changes between the first voltage value V1 and 0 V in a predetermined cycle (see FIG. 10B). Each communication terminal 3 shifts to the inspection mode by receiving the inspection signal via the pair of electric wires 41 and 42. In the inspection mode, it can be inspected whether or not each function of the communication terminal 3 operates normally.

(3.5) Fifth Operation Example Next, a fifth operation example of the communication system 30 will be described.

  The slave unit 2 is configured to shift to the inspection mode when the master unit 1 stops transmitting the synchronization signal for a certain period of time. The slave unit 2 shifts to the inspection mode when the state where the voltage value of the voltage between the pair of electric wires 41 and 42 is the first voltage value V1 continues for a fixed time. After stopping transmission of the synchronization signal for a certain period of time, master device 1 resumes transmission of the synchronization signal. In the inspection mode, the stay determination time is set to, for example, 5 seconds, and when the handset 2 detects the presence of the person 9, the lighting fixture 81 is turned on for 5 seconds. Thereby, it is possible to check whether the communication state between the master unit 1 and the slave unit 2 and whether the human detection function in the slave unit 2 is normal or not.

(4) Modifications Hereinafter, modifications of the communication system 30 of the present embodiment will be described. The modifications described below can be applied by appropriately combining the above-described embodiments or modifications.

(4.1) First Modification In the above-described example, since the master 1 makes the pulse width T2 of the synchronization signal constant, the duty of the synchronization signal also changes according to the time length of the cycle T1. The duty is a period in which the voltage value of the voltage between the pair of electric wires 41 and 42 in the cycle T1 is the first voltage value V1 or the second voltage value V2. In the present embodiment, the duty is a ratio of a period (pulse width T2) in which the voltage value of the voltage between the pair of electric wires 41 and 42 is the second voltage value V2 in the cycle T1. Master device 1 may be configured to modulate only the duty (pulse width T2) of the synchronization signal. The master unit 1 sets the cycle T1 of the synchronization signal constant and sets the pulse width T2 to a time length corresponding to the information to be transmitted to the slave unit 2.

  An operation example of the communication system 30 of the present modification will be described with reference to FIG.

  Here, it is assumed that the lighting apparatus 81 is turned off and the base unit 1 detects the presence of the person 9 in the entry detection mode among the plurality of communication terminals 3 (the base unit 1 and the handset 2).

  The transmission control unit 121 of the parent device 1 causes the transmission unit 141 to transmit a synchronization signal in which the time length of the pulse width T2 is T21 in the cycle T1 because the determination result of the determination unit 124 is "absent state". The time length T21 of the pulse width T2 indicates that the stay determination time which is the setting information is 3 minutes, and the lighting state of the lighting fixture 81 which is the lighting information is being turned off. The slave 2 sets the stay determination time to 3 minutes by measuring the time length T21 of the pulse width T2 of the synchronization signal, and sets the operation mode to the entry detection mode.

  At time t7, the amplitude A1 of the output signal S1 is equal to or greater than the first detection threshold Vth11, and the detection unit 123 of the parent device 1 determines that the person 9 has entered the detection range 91 (the person 9 is present in the detection range 91) Do. Thereby, the lighting fixture 81 is turned on.

  Then, the transmission control unit 121 changes the time length of the pulse width T2 of the synchronization signal from T21 to T22. The time length T22 indicates that the stay determination time as setting information is 3 minutes, and the lighting state of the lighting fixture 81 as lighting information is on. The slave unit 2 switches the operation mode from the entry detection mode to the stay detection mode by measuring the time length T22 of the pulse width T2 of the synchronization signal.

  Furthermore, transmission control unit 121 enters in time slot Ts starting at time T30 after the voltage value of the voltage between the pair of electric wires 41 and 42 changes from the first voltage value V1 to the second voltage value V2. Send a detection signal. After time t7, the amplitude A1 of the output signal S1 becomes equal to or greater than the second detection threshold Vth12, and the transmission control unit 121 transmits a stay detection signal in the time slot Ts.

  In the present modification, the parent device 1 changes only the duty (pulse width T2) of the synchronization signal, but the present invention is not limited to this. The master unit 1 may be configured to modulate both the period T1 and the pulse width T2 of the synchronization signal so as to make the duty constant and change only the period T1.

(4.2) Other Modifications The base-side controller 12 and the child-side controller 22 in the present disclosure include a computer system. A computer system mainly includes one or more processors and memory as hardware. When one or more processors execute the program recorded in the memory of the computer system, the functions as the base unit control unit 12 and the slave unit control unit 22 in the present disclosure are realized. The program may be pre-recorded in the memory of the computer system, may be provided through a telecommunication line, and recorded in a non-transitory recording medium such as a computer system-readable memory card, an optical disc, a hard disk drive, etc. It may be provided. Each of the one or more processors of the computer system is configured with one or more electronic circuits, including a semiconductor integrated circuit (IC) or a large scale integrated circuit (LSI). The plurality of electronic circuits may be integrated into one chip or may be distributed to a plurality of chips. The plurality of chips may be integrated into one device or may be distributed to a plurality of devices. In addition, at least a part of the functions of the base unit side control unit 12 and the handset side control unit 22 may be realized by, for example, a server or a cloud (cloud computing).

  Although the embodiment has described the case where the communication terminal 3 is a moving object detection device that detects the presence or absence of a moving object (person 9) in the detection range, the present invention is not limited to this configuration. For example, the communication terminal 3 may be, for example, a detection device that detects brightness, temperature, and the like. In addition, in the communication terminal 3, a detection function (sensor function) is not an essential structure, and the detection function may be abbreviate | omitted.

  Although the embodiment has described the case where the communication system 30 is a lighting control system that controls the lighting system 80, the present invention is not limited to this configuration. For example, the communication system 30 may be a control system that controls an air conditioner as a load device. In addition, the communication system 30 should just be equipped with the several communication terminal 3, and the function which controls a load apparatus is not essential.

  In the embodiment, the case where the master unit 1 and the slave unit 2 are electrically connected via the pair of electric wires 41 and 42 and wired communication via the pair of electric wires 41 and 42 has been described. Not exclusively. The master unit 1 and the slave unit 2 may be configured to perform wireless communication.

  Although the embodiment has described the case where all of the plurality of communication terminals 3 (the base unit 1 and the handset 2) transmit signals in one common time slot Ts, the present invention is not limited to this configuration. The plurality of communication terminals 3 may include the communication terminals 3 transmitting signals in time slots different from the common time slot in which two or more communication terminals 3 transmit signals.

(5) Summary The communication device (the base unit 1) according to the first aspect includes a communication unit (the base unit communication unit 14) and a control unit (the base unit control unit 12). The communication unit (14) transmits the synchronization signal to the child device (2). The control unit (12) controls the communication unit (14). The synchronization signal is a signal for synchronizing the communication device (1) and the slave (2), and the signal level is periodically switched between at least two values. The control unit (12) has at least a cycle (T1) in which the signal level of the synchronization signal switches between two values, and a duty which is a ratio of a period in which the signal level is one of two values in the cycle (T1). One is modulated in accordance with the information to be transmitted to the slave (2).

  According to this aspect, at least one of the period and the duty of the synchronization signal is modulated according to the information that the communication device (1) transmits to the child device (2). That is, information is included in the synchronization signal that synchronizes the communication device (1) with the slave (2). Therefore, simplification of the signal between the communication device (1) and the child device (2) can be achieved.

  In the first aspect, the communication device (1) according to the second aspect further includes a power supply unit (master device-side power supply unit 13). The power supply unit (13) supplies power to the child device (2) through the pair of electric wires (41, 42). The communication unit (14) transmits the synchronization signal to the slave (2) via the pair of electric wires (41, 42).

  According to this aspect, it is possible to combine wired communication with the child device (2) and power supply to the child device (2).

  In the communication device (1) according to the third aspect, in the second aspect, the synchronization signal is a first voltage in which the voltage value of the voltage between the pair of electric wires (41, 42) is a signal level and the binary It is a voltage signal that changes at least between the value (V1) and the second voltage value (V2). The control unit (12) receives the signal transmitted from the child device (2), in which the voltage value of the voltage between the pair of electric wires (41, 42) changes to the third voltage value (V3).

  According to this aspect, confusion between the synchronization signal and the signal from the child device (2) can be suppressed.

  In the communication device (1) according to the fourth aspect, in any one of the first to third aspects, the control unit (12) sets the slave unit (in one time slot (Ts) set based on the synchronization signal). Receive the signal from 2).

  According to this aspect, it is possible to suppress the reception leak of the signal from the child device (2).

  In the communication device (1) according to the fifth aspect, in the fourth aspect, the control unit (12) transmits a signal to the slave (2) in the time slot (Ts).

  According to this aspect, since the communication device (1) and the child device (2) transmit the signal in one common time slot (Ts), the signal can be simplified.

  In the communication device (1) according to the sixth aspect, in the fourth or fifth aspect, the communication unit (14) can communicate with a plurality of handsets (2). The control unit (12) receives signals from the plurality of handsets (2) in the time slot (Ts).

  According to this aspect, since the plurality of handsets (2) transmit the signal in one common time slot (Ts), the signal can be simplified.

  The child device (2) according to the seventh aspect receives the synchronization signal from the communication device (1) according to any of the first to sixth aspects.

  According to this aspect, at least one of the period and the duty of the synchronization signal is modulated according to the information that the communication device (1) transmits to the child device (2). That is, information is included in the synchronization signal that synchronizes the communication device (1) with the slave (2). Therefore, simplification of the signal between the communication device (1) and the child device (2) can be achieved.

  A communication system (30) according to an eighth aspect includes the communication device (1) according to any one of the first to sixth aspects and a slave device (2) of the seventh aspect.

  According to this aspect, at least one of the period and the duty of the synchronization signal is modulated according to the information that the communication device (1) transmits to the child device (2). That is, information is included in the synchronization signal that synchronizes the communication device (1) with the slave (2). Therefore, simplification of the signal between the communication device (1) and the child device (2) can be achieved.

  A program according to a ninth aspect causes a computer system to function as the control unit (12) of the communication device (1) according to any one of the first to sixth aspects.

  According to this aspect, at least one of the period and the duty of the synchronization signal is modulated according to the information that the communication device (1) transmits to the child device (2). That is, information is included in the synchronization signal that synchronizes the communication device (1) with the slave (2). Therefore, simplification of the signal between the communication device (1) and the child device (2) can be achieved.

1 Master (Communication device)
12 Master unit side control unit (control unit)
13 Base unit power supply unit (power supply unit)
14 Master Unit Communication Unit (Communication Unit)
2 handsets 30 communication system 41, 42

Claims (9)

A communication unit that transmits a synchronization signal to a slave unit;
A control unit configured to control the communication unit;
The synchronization signal is a signal for synchronizing the communication device and the slave, and the signal level is periodically switched between at least two values,
The control unit performs at least one of a cycle in which the signal level of the synchronization signal is switched between the two values and a duty that is a ratio of a period in which the signal level is one of the two values in the cycle. A communication device that modulates according to the information transmitted to the child device. It further comprises a power supply unit for supplying power to the child device via a pair of electric wires,
The communication device according to claim 1, wherein the communication unit transmits the synchronization signal to the child device via the pair of electric wires. The synchronization signal is a voltage signal at which the voltage value of the voltage between the pair of electric wires is at the signal level and at least changes between the first voltage value and the second voltage value which are the binary value,
The communication device according to claim 2, wherein the control unit receives a signal transmitted from the child device, in which a voltage value of a voltage between the pair of electric wires changes to a third voltage value. The communication apparatus according to any one of claims 1 to 3, wherein the control unit receives a signal from the slave device in one time slot set based on the synchronization signal. The communication device according to claim 4, wherein the control unit transmits a signal to the slave in the time slot. The communication unit can communicate with a plurality of the slaves,
The communication device according to claim 4, wherein the control unit receives signals from the plurality of slaves in the time slot. A slave that receives the synchronization signal from the communication device according to any one of claims 1 to 6. The communication device according to any one of claims 1 to 6.
A slave unit according to claim 7, and a communication system.   The program for functioning a computer system as said control part of the communication apparatus of any one of Claims 1-6.

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